Cervical Cancer Screening and Diagnosis
Number: 0443
(Replaces CPB 359)
Table Of Contents
PolicyApplicable CPT / HCPCS / ICD-10 Codes
Background
References
Policy
Scope of Policy
This Clinical Policy Bulletin addresses cervical cancer screening and diagnosis.
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Medical Necessity
- Consistent with guidelines from the U.S. Preventive Services Task Force (USPSTF) and the American College of Obstetricians and Gynecologists (ACOG), Aetna considers annual cervical cancer screening with conventional or liquid-based Papanicolaou (Pap) smears a medically necessary preventive service for non-hysterectomized women age 21 years and older.
- Pap screening is considered medically necessary beginning in adolescence in HIV-infected women. The ACOG guidelines on cervical cancer in adolescents (2010) recommend that adolescents with HIV have cervical cytology screening twice in the first year after diagnosis and annually thereafter.
- Pap screening is considered medically necessary in sexually active immunocompromised adolescent women, including those who have received an organ transplant or those with long-term steroid use. According to ACOG guidelines (2010), sexually active immunocompromised adolescents, including those who have received an organ transplant or those with long-term steroid use, should undergo screening after the onset of sexual activity and not wait until 21 years of age. The testing should be done at 6-month intervals during the first year of testing and then annually thereafter.
- Pap screening is considered medically necessary beginning in adolescence in women diagnosed with cervical dysplasia or cervical cancer, with testing twice in the first year after diagnosis and annually thereafter.
- Pap smears is considered medically necessary beginning in adolescence in sexually active women who have been exposed in utero to diethylstilbestrol (DES). Testing should begin after the onset of sexual activity, and should be done at 6-month intervals during the first year of testing and then annually thereafter.
- Pap smear screening is considered not medically necessary for women who have undergone complete (total) hysterectomy for benign disease (e.g., no evidence of cervical neoplasia or cancer) or have absent cervix.
Note: Medically necessary cervical cancer screening is covered under plans that cover routine physical exams, routine gynecological exams and/or routine Pap smears. Please check benefit plan descriptions for details.
Diagnostic Pap smears are considered medically necessary when any of the following conditions is met:
- Pap smear is accompanied by a diagnosis of a malignancy of the female genital tract (i.e., cervix, ovary, uterus, or vagina); or
- There is a description of symptoms or a disease requiring diagnosis by a Pap smear, for example:
- Abnormal vaginal bleeding or discharge
- Chronic cervicitis
- Vaginal tumor; or
- Following gynecological surgery for cancer; or
- Member has been exposed to diethylstilbestrol (DES); or
- Member has any of the following risk factors for cervical cancer:
- History of cervical, vaginal or vulvar cancer
- HIV infection
- History of genital human papillomavirus (HPV) infection
- Immunosuppression
- Multiple sexual partners
- Previously abnormal Pap smear
- Previous sexually transmitted disease.
Aetna considers diagnostic Pap smears experimental, investigational, or unproven for all other indications because its effectiveness for indications other than the ones listed above has not been established.
- Automated liquid-based thin-layer slide preparation methods (e.g., ThinPrep® PapTest™, SurePrep™ Liquid Based Pap Test, AutoCyte PREP System™) is considered medically necessary as an alternative to conventional Pap smears when the criteria for conventional Pap smears are met.
- Automated cervical cancer slide interpretation systems (e.g., FocalPoint Slide Profiler (formerly AutoPap), PAPNET) is considered a medically necessary adjunct to cervical cancer screening.
- p16/Ki-67 dual staining is considered medically necessary for women with a positive HPV screening test
- Testing for high-risk strains of HPV DNA using Food and Drug Administration (FDA)-approved techniques (e.g., Hybrid Capture II, cobas HPV PCR, Aptima HPV assay) is considered medically necessary for women with any of the following indications:
- Assessment of women with atypical squamous cells of undetermined significance (ASCUS). This is consistent with the National Cancer Institute's interim guidelines for managing abnormal cervical cytology as well as the position of the American Society for Colposcopy and Cervical Pathology (ASCCP) for the management of ASCUS; or
- Follow-up of women with ASCUS who have a previously positive HPV DNA test and negative colposcopy results within the past 2 years; or
- Follow-up of women with low-grade squamous intra-epithelial lesions (LSIL) who have had negative colposcopy results within the past 2 years; or
- Follow-up of women with atypical squamous cells: Cannot exclude high-grade SIL (ASC-H) who have negative colposcopy results within the past 2 years; or
- Use in combination with Pap smears for screening women aged 30 years and older. If this combination is used for screening, it is not considered medically necessary to re-screen women who receive negative results on both tests more frequently than every 3 years; or
- High-risk HPV testing alone for screening women aged 30 and older every 5 years; or
- Assessment of women with atypical glandular cells not otherwise specified (AGC NOS); or
- Follow-up of women with AGC NOS who have had negative colposcopy results within the past 2 years.
Note: The medically necessary indications for HPV DNA testing are not affected by pregnancy status.
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Experimental, Investigational, or Unproven
The following procedures are considered experimental, investigational, or unproven because the effectiveness of these approaches has not been established:
- Artificial intelligence-based cervical cancer screening
- Cervicography or speculoscopy (Pap-Sure) for the screening or diagnosis of cervical cancer
- DNA methylation as a triage marker for colposcopy referral in HPV-based cervical cancer screening
- DYSIS Smart Colposcopy for screening of cervical cancer
- Fluorescence in-situ hybridization (FISH) testing (e.g., the Ikonisys oncoFISH cervical test) for cervical cancer screening or diagnosis
- HPV testing for the following indications:
- Use of HPV tests as a primary screening test for cervical cancer in women younger than 30 years of age. According to evidence-based guidelines from the U.S. Preventive Services Task Force, the medical literature does not support HPV testing as a screening test for cervical cancer for younger individuals whose cervical cytology is normal or is unknown;
- For selecting candidates for cervical cancer vaccine. The Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices does not recommend HPV testing to select persons for cervical cancer vaccine;
- For testing members with definitively positive cervical cytology, other than follow-up of women with ASC-H, LSIL or AGC NOS and negative colposcopy;
- Testing for low-risk HPV strains;
- Testing of men;
- Use for indications other than detection of cervical cancer, such as testing for infection following exposure to HPV;
- For use in girls and women less than 21 years of age unless they have had a previous abnormal Pap smear that meets criteria above;
- Use for all indications other than those listed in section XI above
- Pap smear screening for all other women under 21 years of age because they have no proven value for these younger women
- PreTect HPV-Proofer/PreTect Proofer 7 HPV mRNA E6 and E7 Biomarker Test for screening cervical dysplasia or cancer and other indications
- QuantiVirus HPV E6/E7 mRNA test for cervical cancer screening or diagnosis
- Resolve laboratory testing kit (Gynecor, Glen Allen, VA) for cervical cancer screening or diagnosis
- Self-collected / self-sampling HPV tests for screening of cervical cancer
- Spectroscopy/optical/optoelectric detection systems (e.g., the Luma cervical imaging system, and TruScreen) for cervical cancer screening or diagnosis
- Use of methylation markers for cervical cancer screening
- Video colpography for cervical cancer screening or diagnosis.
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Related Policies
Background
Pap smears consist of cells removed from the cervix, which are specially prepared for microscopic examination. The cells are removed by brushing or scraping the cervix during a pelvic examination and then placing the cells on one or more glass slides. Each slide typically contains hundreds of thousands of cells. All Pap smears should be sent to an accredited laboratory to be stained, examined under a microscope, and interpreted. The test is used as the principal screening test to detect cervical cancer in asymptomatic women. It can detect precancerous changes or cancer of the cervix or vagina. A Pap test will only rarely detect cancer of the ovaries or endometrial cancer. It can also find some infections of the cervix and vagina.
The American Academy of Family Physicians recommends that all women who are or have been sexually active, or who have reached age 18, should have annual Pap smears. The American Cancer Society, National Cancer Institute, and American Medical Association recommend that cervical cytology screening should begin within 3 years of onset of sexual activity or age 21. The recommendation allows less frequent Pap testing after 3 or more annual smears have been normal, at the discretion of the physician. For women who have had repeated negative tests, the marginal gain from screening more often than every 3 years decreases sharply. However, because of the difficulty in identifying patients at increased risk for cervical cancer, most physicians will recommend a Pap test be performed at least once-yearly.
The American College of Obstetricians and Gynecologists (ACOG, 2009) recommend that cervical cytology screening begin at age 21 regardless of age at onset of sexual activity and from age 21 to 29, testing is recommended every 2 years but should be more frequent in women who are HIV-positive, immunosuppressed, were exposed in- utero to diethylstilbestrol (DES), or have been treated for cervical intraepithelial neoplasia (CIN) grade 2, 3 or cervical cancer. The ACOG guidelines on cervical cancer in adolescents (2010) recommend that adolescents with HIV have cervical cytology screening twice in the first year after diagnosis and annually thereafter. Sexually active immunocompromised adolescents, including those who have received an organ transplant or those with long-term steroid use, should undergo screening after the onset of sexual activity and not wait until 21 years of age. The testing should be done at 6-month intervals during the first year of testing and then annually thereafter. Beginning at age 30, women who have 3 consecutive negative screens and who do not fit the criteria above for more frequent screening, may be tested every 3 years. Co-testing with cervical cytology and high-risk human papillomavirus (HPV) typing is also appropriate and if both tests are negative, re-screening in 3 years is recommended.
Although ACOG (2013) guidelines state that women younger than 21 years should not undergo screening, they also state that "[i]f a woman younger than 21 years is inadvertently screened and has an abnormal test result, the result should not be ignored and should be managed based on the guidelines for 21–24-year-old women.” Similarly, the American Society for Colposcopy and Cervical Pathology (ASCCP) (Massad et al, 2012) states that ”[g]uidelines for women aged 21-24 years can be extrapolated to adolescents inadvertently screened.”
After age 65, there is no clear consensus on the need for Pap smears in women who have had previous adequate screening. The American Academy of Family Physicians recommends that at age 65, screening may be discontinued if there is documented evidence of previously negative smears; however, these recommendations are currently under review. The ACOG (2009) recommend discontinuation of screening after age 65 or 70 in women with 3 or more negative consecutive tests and no cervical abnormalities during the previous 10 years. Women with histories of CIN grade 2, 3 or cancer should undergo annual screening for 20 years after treatment. The American College of Physicians (ACP) recommends Pap smears every 3 years for women aged 20 to 65, and every 2 years for women at high-risk. The ACP also recommends screening women aged 66 to 75 every 3 years if not screened in the 10 years before age 66.
The U.S. Preventive Services Task Force (USPSTF, 2018) recommends screening for cervical cancer every 3 years with cervical cytology alone in women aged 21 to 29 years. For women aged 30 to 65 years, the USPSTF recommends screening every 3 years with cervical cytology alone, every 5 years with high-risk human papillomavirus (hrHPV) testing alone, or every 5 years with hrHPV testing in combination with cytology (co-testing). The USPSTF recommends against screening for cervical cancer in women older than 65 years who have had adequate prior screening and are not otherwise at high risk for cervical cancer.
Pap testing need not be performed for women who had a hysterectomy for benign disease; however, women who had a hysterectomy performed in which the cervix was left intact probably still require screening. However, a recent study by Sirovich and Welch (2004) indicated that many U.S. women who have undergone hysterectomy are undergoing Pap smear screening despite the U.S. Preventive Services Task Force's recommendation that Pap smear screening is unnecessary for women who have undergone a complete hysterectomy for benign disease.
A federally funded survey of 1,100 clinicians (internists, family practitioners, or obstetrician-gynecologists) found that only about 1/5 consistently follow guidelines for Pap testing (Yabroff et al, 2009). While over 80 % said that at least one set of screening guidelines (e.g., U.S. Preventive Services Task Force) was "very influential" in their practices, only 22 % recommended guideline-consistent care for every clinical scenario included in the survey. Obstetrician-gynecologists were less guideline-concordant than the other specialties. Of note, 1/3 of participants recommended annual Pap testing for an 18-year old who hadn't had sexual intercourse, while almost 1/2 continued to recommend Pap testing for a women whose cervix had been removed for benign reasons.
Repeat Pap smears may be indicated 3 to 4 months following local treatment of vaginal infection/inflammation, and 2 to 3 months following a Pap test suggestive of mild dyskaryosis or if the initial Pap smear results were unsatisfactory due to inadequate sampling.
A standardized method of reporting cytology findings was developed by the National Cancer Institute called the "Bethesda System". In the Bethesda System, atypical squamous cells fall into 2 categories:
- atypical squamous cells of undetermined significance (ASCUS) and
- atypical squamous cells: cannot exclude HSIL (ASC-H).
Cervical cancer precursors fall into 2 categories:
- low-grade squamous intraepithelial lesions (LSIL) and
- high-grade squamous intraepithelial lesions (HSIL).
Low-grade squamous intraepithelial lesions include CIN 1 (mild dysplasia) and the changes of HPV, termed koilocytotic atypia. High-grade squamous intraepithelial lesions include CIN 2 and CIN 3 (moderate dysplasia, severe dysplasia, and carcinoma in situ). Other classification systems in use include the Dysplasia/CIN System and the Papanicolaou System.
Currently there are no formal guidelines for anal Pap smear screening. The Centers for Disease Control and Prevention (Workowski and Bolan, 2015) stated: "Data are insufficient to recommend routine anal-cancer screening with anal cytology in persons with HIV infection or HIV-negative MSM. More evidence is needed concerning the natural history of anal intraepithelial neoplasia, the best screening methods and target populations, safety of and response to treatments, and other programmatic considerations before screening can be routinely recommended. However, some clinical centers perform anal cytology to screen for anal cancer among high-risk populations (e.g., persons with HIV infection and MSM), followed by high-resolution anoscopy for those with abnormal cytologic results (e.g., ASC-US)." Observing that HIV-infected men and women with human papillomavirus (HPV) infection are at increased risk for anal dysplasia and cancer, the HIV medicine association of the Infectious Diseases Society of America (Aberg, et al, 2013) states that MSM, women with a history of receptive anal intercourse or abnormal cervical Pap test results, and all HIV-infected persons with genital warts should have anal Pap tests. This is a weak recommendation based upon moderate quality evidence.
Automated Liquid-Based Thin-Layer Slide Preparation (e.g., ThinPrep, SurePath, AutoCyte PREP)
To decrease the number of false-negative Pap smears, new technologies for preparing the Pap smear have been approved by the U.S. Food and Drug Administration (FDA).
The ThinPrep® PapTest™ (Cytyc Corp., Marlborough, MA), and SurePath (TriPath Imaging Inc., Burlington, NC) are automated liquid-based thin layer slide preparation techniques. With the ThinPrep System, a conventional Pap smear is not performed. Using a spatula and a brush or a cervical broom, the cervical area is sampled and the devices are rinsed in a fixative solution. The slide is then automatically made in the laboratory, which decreases the possibility of air-drying artifacts. It is then stained and read by a technician or a cytopathologist. SurePath (formerly known as AutoCyte PREP) is another liquid-based thin-layer sample preparation system that uses centrifugation to separate cells from obscuring material, and automatically prepares and stains cytology slides.
An assessment of liquid-based cervical cytology systems by the Institute for Clinical Systems Improvement (ICSI, 2003) concluded that liquid-based cytology is an acceptable alternative to conventional Pap testing for cervical cancer screening. The ICSI technology assessment made the following findings:
- For the detection of pre-invasive cervical lesions, liquid-based cytology is comparable to conventional Pap; there is no evidence of a change in the rate of cancer detection when liquid-based samples are analyzed.
- For minor grade lesions, there is evidence of a higher detection rate with liquid-based cytology. As a result, liquid-based cytology acts to normalize the rate of detection of atypical squamous cells of undetermined significance (ASCUS) so that pathologists can reach the 3 % to 5 % ASCUS rate expected (Bethesda criteria). More accurate detection of ASCUS helps to better identify patients who need further testing. Inter-observer validity is higher with LBC.
- Of 11 studies cited in the ICSI technology assessment that presented test results as either satisfactory, satisfactory but limited by, or unsatisfactory, 8 found a higher rate of satisfactory samples with liquid-based cytology. Between 75.6 % and 97.7 % of liquid-based cytology preparations were satisfactory compared with 60.5 % to 97.5 % with conventional Pap preparations.
- The ICSI report cited the results of a meta-analysis of 15 studies that reported a sensitivity of 80 % for liquid-based cytology and 72 % for conventional Pap testing predominantly for the detection of low-grade squamous intraepithelial lesions or more severe (LSIL+) by histology and/or independent pathology review of slides with a Pap test result of LSIL+. Specificity did not differ between conventional and liquid-based cytology preparations.
A technology assessment by the Canadian Coordinating Office for Health Technology Assessment found that "[e]vidence (based primarily on results from split-sample trials) suggests that compared with Pap smears, the use of [liquid-based cytology] reduces the proportion of unsatisfactory specimens and generates fewer false negatives for ordinary populations, but not for high-risk populations" (Noorani et al, 2003).
In its updated guidelines on cervical cancer screening, the American Cancer Society has stated that liquid-based thin-layer Pap smears are an acceptable alternative to conventional Pap smears (Saslow et al, 2002). "As an alternative to conventional cervical cytology smears, cervical screening may be performed every two years using liquid-based cytology; at or after age 30, women who have had 3 consecutive, technically satisfactory normal/negative cytology results may be screened every 2 to 3 years (unless they have a history of in utero DES exposure, are HIV+, or are immunocompromised)."
An assessment by the Danish Centre for Evaluation and Health Technology Assessment (DACEHTA, 2005) concluded that "no scientific basis has been found to suggest any difference in clinical or health economic effect between liquid based cytology (LBC) and conventional Pap smear (CPS)." The report noted that "[i] the objective is to improve the clinical or health economic effectiveness, the report demonstrates that an increased coverage rate and an expansion of the age interval included in screening programmes for cancer of the uterine cervix from 59 to 69 years of age would be the more efficient strategy."
A recent large-scale clinical trial found that liquid-based cytology does not perform better than conventional Pap tests in terms of relative sensitivity and PPV for detection of cervical cancer precursors. In a randomized double-blind controlled trial, Siebers and colleagues (2009) compared liquid-based cytology with conventional cytology for detection of cervical cancer precursors in women (n = 89,784) aged 30 to 60 years participating in the Dutch cervical screening program. A total fo 122 practices were assigned to use liquid-based cytology and screened 49,222 patients and 124 practices were assigned to use the conventional Pap test and screened 40,562 patients. Patients were followed for 18 months. The adjusted detection rate ratios for CIN grade 1+ was 1.01 (95 % confidence interval [CI]: 0.85 to 1.19); for CIN grade 2+, 1.00 (95 % CI: 0.84 to 1.20); for CIN grade 3+, 1.05 (95 % CI: 0.86 to 1.29); and for carcinoma, 1.69 (95 % CI: 0.96 to 2.99). The adjusted positive predictive value (PPV) ratios, considered at several cytological cut-offs and for various outcomes of CIN did not differ significantly from unity.
Automated System (FocalPoint, PAPNET)
Automated slide analysis devices (e.g., PapNet (Neuromedical Systems Inc.), FocalPoint (formerly AutoPap) (TriPath Technologies, Inc., AutoCyte SCREEN (AutoCyte, Inc.)) are designed to partially automate screening of Pap smears. The primary focus of current research is on use of image analysis as a primary screening device, where Pap smear slides are translated into digitalized images for automated image analysis. Slides that are identified by automated image analysis as possibly abnormal are passed on for manual interpretation. Slides that are identified by automated image analysis as very unlikely to contain abnormal cells may not be examined manually, or a random sample may be spot checked manually. Automated slide analysis devices may also be used to rescreen slides that are reported as negative or inadequate.
Although it is not known whether programs employing automated slide analysis are more effective than manual screening in detecting more cervical cancers, automated slide analysis devices have become standard of care. An Agency for Healthcare Research and Quality technology assessment of cervical cancer screening techniques (McCrory et al, 1999) concluded that there is substantial uncertainty about the estimates of sensitivity and specificity of cervical cancer screening using automated slide analysis devices compared with conventional manual screening, which in turn results in substantial uncertainty about the estimates of the effectiveness and cost-effectiveness of these techniques. "Although it is clear that both thin-layer cytology and computerized rescreening technologies provide an improvement in effectiveness at higher cost, the imprecision in estimates of effectiveness makes drawing conclusions about the relative cost-effectiveness of thin-layer cytology and computerized rescreening technologies problematic."
A technology assessment for the Minnesota Health Technology Advisory Committee (1999) concluded: "Studies of these methods demonstrate that computer-assisted cervical cancer screening and rescreening modestly improves detection of false-negative smears as compared with conventional manual screening. The majority of false-negative smears detected are low-grade squamous intraepithelial lesions (LGSIL), reactive or reparative changes, or atypical squamous cells of undetermined significance (ASCUS) rather than the more serious premalignant or malignant lesions. Some studies have shown that computer-assisted Pap smear screening may marginally improve health outcome for some patients. The net health benefits of computer-assisted screening have not been proven. Studies examining the cost-effectiveness of the new technologies indicate that the cost-benefit of computer-assisted rescreening technologies is less favorable than any manual rescreening alternatives."
An assessment of the use of automated slide analysis devices in cervical cancer screening conducted by the Research Triangle Institute Evidence-Based Practice Center for the Agency for Healthcare Research and Quality (Hartmann et al, 2002) concluded that "[o]verall, the quality of this literature is poor for the purposes of making decisions about choice of screening systems in US populations. No randomized trials or prospective cohort studies relate use of a screening modality over time to outcomes for individual women. The cost-effectiveness of use of new technologies has only been estimated, not measured directly."
More recently, the U.S. Preventive Services Task Force (USPSTF, 2003) reached the following conclusions regarding cervical cancer screening using automated slide analysis devices: "The USPSTF concludes that the evidence is insufficient to recommend for or against the routine use of new technologies to screen for cervical cancer. The USPSTF found poor evidence to determine whether new technologies, such as liquid-based cytology, computerized rescreening, and algorithm based screening, are more effective than conventional Pap smear screening in reducing incidence of or mortality from invasive cervical cancer. Evidence to determine both sensitivity and specificity of new screening technologies is limited. As a result, the USPSTF concludes that it cannot determine whether the potential benefits of new screening devices relative to conventional Pap tests are sufficient to justify a possible increase in potential harms or costs.
An assessment for the European Cervical Cancer Screening Network's Guidelines for Quality Assurance in Cervical Cancer Screening (Nieminen, 2003) summarized the current evidence for automated cervical cancer slide analysis devices: "There are several articles published concerning the performance of automation assisted screening. They show generally a better sensitivity with at least same specificity than conventional screening. Most of these articles have been retrospective (quality control) and/or relatively small numbers of smears have been studied. However, randomized, prospective public health trials in primary screening setting have been published very few. The show equal or slightly better performance compared to manual conventional screening …. When implementing the new methods, it is needed to carefully ascertain and evaluate the performance of the method in primary (public health) screening up to the final invasive end points with randomized prospective studies."
An assessment for the National Coordinating Centre for Health Technology Assessment (Willis et al, 2005) concluded: "As in previous health technology assessments on this subject, the conclusion is that the available evidence on test performance, impact on process and cost-effectiveness is still insufficient to recommend implementation of automated image analysis systems. The priority for action remains further research."
Wain (1997) has commented that "[t]he performance of automated techniques in quality assurance should be assessed against other methods of quality assurance, such as random re-screening of a mandated proportion of smears, directed re-screening of 'high-risk' groups and 'rapid re-screening'."
In its updated guidelines on cervical cancer screening, the American Cancer Society expert review panel (Saslow et al, 2002) only considered screening technologies with sufficient published clinical data, and excluded cervical cancer screening with automated slide analysis devices from its consideration.
HPV Testing
Human papillomavirus (HPV) has been associated with the development of CIN and invasive cancer of the cervix. Recent prospective studies have shown that abnormal Pap smears that are positive for oncogenic HPV strains are much more likely to be associated with abnormal colposcopic findings than abnormal Pap smears that are HPV negative. There is no proven value for testing for additional "low-risk" strains of HPV that have not been associated with substantially elevated cancer risk.
HPV testing has been used as an adjunctive reflex test in women with ASCUS to identify those at highest risk for cervical cancer, who should go on to receive definitive colposcopy. HPV testing of patients with ASCUS can be used to identify patients at highest risk of underlying cervical dysplasia, and minimize the number of unnecessary colposcopic examinations in women who have no disease. Women with ASCUS who have a positive HPV and no lesions on colposcopy should be followed-up with repeat Pap testing at 6 and 12 months or with HPV testing at 12 months. Current guidelines do not recommend reflex testing of women with squamous intraepithelial lesions (HSIL, ASC-H, or LSIL). However, guidelines from the American Society of Colposcopy and Cervical Cytology (Wright et al, 2002; Wright et al, 2007) recommend that women with LSIL or ASC-H with no lesions on colposcopy should be followed-up with repeat Pap testing at 6 and 12 months or with HPV testing at 12 months.
HPV testing has also been proposed as a primary screening test to be performed simultaneously with Pap smear screening. Digene Corp. received FDA approval for a test that combines the Pap smear with a genetic exam for 13 oncogenic strains of HPV.
The ACOG (2009) concluded, based on "good and consistent scientific evidence" that the use of a combination of cervical cytology and HPV DNA screening is appropriate for women aged 30 years and older. According to ACOG (2009), if this combination is used, women who receive negative results on both tests should be re-screened no more frequently than every 3 years. ACOG's recommendation was based on the results of studies that demonstrated that women aged 30 years and older who had both negative cervical cytology test results and negative high-risk type HPV-DNA test results were at extremely low-risk of developing CIN 2 or CIN 3 during the next 4 to 6 years. ACOG guidelines explain that any woman aged 30 years or older who receives negative test results on both cervical cytology screening and HPV DNA testing should be re-screened no more frequently than every 3 years. The ACOG guidelines state that the combined use of these modalities has been shown to increase sensitivity but also decrease specificity and increase cost. However, ACOG estimated that the increase in screening interval will offset the cost of this new screening regimen.
The ACOG guidelines (2009) stated that the combination of cytology and HPV DNA screening should be restricted to women aged 30 years and older because transient HPV infections are common in women younger than 30 years, and a positive test result may lead to unnecessary additional evaluation and treatment. The ACOG guidelines on cervical cancer in adolescents (2010) stated that HPV testing is not recommended at any time in adolescents because of the high prevalence of HPV infection in adolescents and there is little utility in HPV testing in this population; there are no clinical situations, screening, triage, or follow-up that require HPV testing in this population and if conducted, a positive test result should not influence management. The guidelines stated that there is no role for HPV testing in the patient before HPV vaccination. Furthermore, the ACOG guidelines (2010) stated that adolescents who have low- to high-grade precancerous lesions (dysplasia) – with the exception of cervical intraepithelial neoplasia 3 (CIN 3) – generally should be managed by periodic observation. The guidelines stated that re-screening can be delayed until age 21 when the Pap test results show regression of the dysplasia, but annual screening also is an acceptable alternative.
Published studies of cervical cancer screening using a combination of cytology and HPV DNA tests have predominantly employed conventional Pap smears for assessment of cervical cytology. Although there are no studies directly comparing the screening performance of HPV-cytology combination testing using a conventional Pap versus liquid-based cervical cytology, available indirect evidence suggests that there is no clinically significant difference in the screening performance of HPV-cytology combination testing regardless of whether conventional or liquid-based cervical cytology is used (Lorincz and Richart, 2003).
In April 2014, the FDA modified the labeling of cobas, a currently marketed HPV test, to include the additional indication of primary cervical cancer screening (HPV primary screening). Based on the HPV test’s equivalent or superior effectiveness for primary cervical cancer screening compared with cytology alone in a large U.S.-based study of HPV primary screening, known as the Addressing the Need for Advanced HPV Diagnostics trial, the FDA modified the labeling of the test to include an indication for its use for primary screening in women starting at age 25 years. In 2015, ASCCP and Society of Gynecologic Oncology (SGO) published interim guidance for the use of the cobas FDA-approved HPV test for primary cervical cancer screening (Huh, et al, 2015). The interim guidance panel concluded that because of its equivalent or superior effectiveness, in women 25 years and older, the FDA-approved primary HPV screening test can be considered as an alternative to current cytology-based cervical cancer screening methods. The ASCCP and SGO interim guidance (Huh, et al, 2015) states that the test should not be used in women younger than 25 years; these women should continue to be screened with cytology alone. Rescreening after a negative primary HPV screening result should occur no sooner than every 3 years. Positive test results should be triaged with genotyping for HPV-16 and HPV-18, and if the genotyping test results are negative, with cytology testing. If genotyping and cytology test results are negative, patients should have follow-up testing in 1 year.
ACOG (2016) states that major society guidelines currently recommend HPV testing for cervical cancer screening only for women 30 years of age and older, but indicated that use of the cobas HPV test may be considered in women age 25 years and older: "In women 25 years and older, the FDA-approved primary HPV screening test can be considered as an alternative to current cytology-based cervical cancer screening methods. Cytology alone and co-testing remain the options specifically recommended in current major society guidelines. If screening with primary HPV testing is used, it should be performed as per the ASCCP and SGO interim guidance." Guidelines on cervical cancer screening from the U.S. Preventive Services Task Force are currently under review.
The National Cancer Institute is currently sponsoring a multi-center 5-year clinical trial directed at determining the role of HPV testing in the management of cervical disease. Interim guidelines for the management of abnormal cytologic findings in the cervix were developed at a work-shop sponsored by the NCI, which concluded that HPV testing can be used as an adjunctive test to help identify patients at low- or high-risk of developing CIN and cancer. The American Society of Colposcopy and Cervical Pathology has also issued guidelines for the management of ASCUS which incorporated HPV testing and typing to determine which women with ASCUS should undergo colposcopy.
There are no current guidelines recommending HPV testing of men (CDC, 2006; Workowski and Berman, 2006). There is no FDA-approved HPV test for men, and there are no studies demonstrating benefit of testing men for HPV infection. Unlike with cervical ASCUS, HPV typing has not been shown to aid in predicting which patients with anal ASCUS are at risk for high-grade anal intraepithelial neoplasia (AIN) (Panther et al, 2003).
Saqi and colleagues (2006) evaluated the potential role of HPV DNA testing on atypical glandular cells (AGC) cases. Hybrid Capture 2 (Digene Corp.) testing was performed on 144 cervical/endo-cervical AGC specimens. A total of 103 of 144 cases had follow-up; 60/103 (58.3 %) were high-risk HPV negative and 43/103 (42.3 %) were high-risk HPV positive. Of 43 HPV-positive patients, 37 had adenocarcinoma in situ (AIS), ASCUS, or cervical squamous intra-epithelial neoplasia, while only 1 patient without high-risk HPV had a squamous intraepithelial neoplasia. Furthermore, most high-risk HPV positive AGC cases harbored high-grade squamous intra-epithelial lesion rather than AIS. The authors concluded that their findings support HPV DNA testing of all AGC specimens to detect cervical, especially squamous, neoplasia.
The American Society for Colposcopy and Cervical Pathology (ASCCP)'s guidelines for the management of women with abnormal cervical cancer screening tests (Wright et al, 2007) noted that HPV testing is incorporated into the management of AGC after their initial evaluation with colposcopy and endometrial sampling. The recommended post-colposcopy management of women with AGC is to repeat cytologic testing combined with HPV DNA testing at 6 months if they are HPV DNA positive and at 12 months if they are HPV DNA negative. Referral to colposcopy is recommended for women who subsequently test positive for HPV DNA or who are found to have ASCUS or greater on their repeat cytologic tests. If both tests are negative, women can return to routine cytologic testing.
In a randomized study, Mayrand et al (2007) examined if testing for DNA of oncogenic HPV is superior to the Pap test for cervical cancer screening. These investigators compared HPV testing, using an assay approved by the FDA, with conventional Pap testing as a screening method to identify high-grade CIN in women aged 30 to 69 years. Women with abnormal Pap test results or a positive HPV test (at least 1 pg of high-risk HPV DNA per milliliter) underwent colposcopy and biopsy, as did a random sample of women with negative tests. Sensitivity and specificity estimates were corrected for verification bias. A total of 10,154 women were randomly assigned to testing. Both tests were performed on all women in a randomly assigned sequence at the same session. The sensitivity of HPV testing for CIN of grade 2 or 3 was 94.6 % (95 % CI: 84.2 to 100), whereas the sensitivity of Pap testing was 55.4 % (95 % CI: 33.6 to 77.2; p = 0.01). The specificity was 94.1 % (95 % CI: 93.4 to 94.8) for HPV testing and 96.8 % (95 % CI: 96.3 to 97.3; p < 0.001) for Pap testing. Performance was unaffected by the sequence of the tests. The sensitivity of both tests used together was 100 %, and the specificity was 92.5 %. Triage procedures for Pap or HPV testing resulted in fewer referrals for colposcopy than did either test alone but were less sensitive. No adverse events were reported. The authors concluded that as compared with Pap testing, HPV testing has greater sensitivity for the detection of CIN.
An assessment by the California Technology Assessment Forum (CTAF, 2008) found HPV testing for primary cervical cancer screening did not meet CTAF criteria. The CTAF assessment found that, although incorporation of HPV screening can lead to earlier detection of carcinoma in situ lesions, whether or not this will result in reduced cervical cancer incidence and mortality is not known. The CTAF assessment noted, in addition, that the 2 trials that have published long term follow-up used a PCR test that is not currently available in the United States. The CTAF assessment concluded that the evidence is insufficient to recommend for or against the incorporation of HPV testing into cervical cancer screening programs.
Thus, whether HPV testing can replace conventional Pap cytologic testing for cervical cancer screening awaits results from randomized controlled trials and/or recommendations from leading national medical organizations.
Sankaranarayanan and colleagues (2009) began to measure the effect of a single round of screening by testing for HPV, cytologic testing, or visual inspection of the cervix with acetic acid (VIA) on the incidence of cervical cancer and the associated rates of death in the Osmanabad district in India. In this cluster-randomized trial, 52 clusters of villages, with a total of 131,746 healthy women between the ages of 30 and 59 years, were randomly assigned to 4 groups of 13 clusters each. The groups were randomly assigned to undergo screening by HPV testing (n = 34,126), cytologic testing (n = 32,058), or VIA (n = 34,074) or to receive standard care (n = 31,488, control group). Women who had positive results on screening underwent colposcopy and directed biopsies, and those with cervical pre-cancerous lesions or cancer received appropriate treatment. In the HPV-testing group, cervical cancer was diagnosed in 127 subjects (of whom 39 had stage II or higher), as compared with 118 subjects (of whom 82 had advanced disease) in the control group (hazard ratio for the detection of advanced cancer in the HPV-testing group, 0.47; 95 % CI: 0.32 to 0.69). There were 34 deaths from cancer in the HPV-testing group, as compared with 64 in the control group (hazard ratio, 0.52; 95 % CI: 0.33 to 0.83). No significant reductions in the numbers of advanced cancers or deaths were observed in the cytologic-testing group or in the VIA group, as compared with the control group. Mild adverse events were reported in 0.1 % of screened women. The authors concluded that in a low-resource setting, a single round of HPV testing was associated with a significant reduction in the numbers of advanced cervical cancers and deaths from cervical cancer.
In an editorial that accompanied the afore-mentioned article, Schiffman and Wacholder (2009) stated that "[i]n developed nations, HPV testing at extended screening intervals could eventually replace repeated cytologic testing as the primary screening method. Cytologic testing might be used to stratify risk further by identifying HPV-positive women at highest risk for cancer. In these countries, a widespread transition from a good method (frequent cytologic testing) to a better one (less frequent HPV screening) will require high-quality testing that is widely available and properly priced, the establishment of correct screening intervals and related health messages, and the promulgation of clinical guidelines and reimbursement policies to avoid overtreatment of benign infections". Schiffman and Wacholder also noted that, "[i]n the United States, switching to primary HPV screening will be contentious, partly because lengthening the interval between cervical screenings seriously disrupts established gynecologic clinical practice".
Davis (2009) stated that "[i]n showing that a single round of HPV screening (compared with cytologic or VIA screening) had the most marked effect on preventing cervical cancer deaths, these results have tremendous international health implications: Single rounds of HPV screening are much easier to implement than repetitive cytologic screening, particularly in resource-poor countries where cervical cancer is relatively common. Nonetheless, we should not rush to apply such findings to populations with optimal resources. Clinicians in the U.S. should continue to screen as recommended by the American Society for Colposcopy and Cervical Pathology".
Cervicography and Speculoscopy
Cervicography is a procedure in which the cervix is swabbed with an acetic acid solution to identify acetowhite changes in the cervix. With cervicography, a photograph of the cervix is taken with a special camera (Cerviscope), and is sent to trained technicians for evaluation (National Testing Laboratories, St. Louis, MO). The technicians determine whether the visual image is most compatible with normal, atypia/metaplasia, intraepithelial neoplasia, or cancer. In contrast, speculoscopy (PapSure) uses a chemiluminescent light to aid naked-eye or minimally magnified visualization of acetowhite changes on the cervix. Both cervicography and speculoscopy have been used as an adjunct to Pap smear for cervical cancer screening and as a triage method to identify which patients with low grade atypical Pap smears need further evaluation by colposcopy and biopsy. According to practice guidelines from the ASCCP, "there have been insufficient large scale controlled studies related to their use in the triage of LGISL [low grade squamous intraepithelial lesion] to recommend either for or against their use" (Cox et al, 2000). An International Academy of Cytology (IAC) Task Force (van Niekerk et al, 1998) concluded that "[t]he role of cervicography, or high resolution photography, as a screening device remains to be defined." The IAC Task Force also noted that "[t]here are, at present, insufficient data for the evaluation of speculoscopy…." The U.S. Preventive Services Task Force (1996) concluded that "[t]here is insufficient evidence to recommend for or against routine screening with cervicography … although recommendations against such screening can be made on other grounds."
Video Colpography
Video colpography (video colposcopy) has been used for imaging the vagina and cervix, and has been proposed for use as a method of cervical cancer screening. In this procedure, a video camera is used to create computerized digital images of the cervix, vaginal fornices and endocervical canal; the system may be interfaced with a computer for image manipulation. The images are evaluated by a video screener for signs of cervical cancer. Etherington et al (1997) stated that video colpography has potential advantages as a portable and rapid method of cervical imaging. The investigators stated that video colpography has potential of use in fields of teaching, audit and screening of women with low-grade smear abnormalities. Etherington et al (1997) compared video colpography with colposcopy in a pilot study involving 50 women referred for colposcopy. The investigators reported that the video colpography images were satisfactory or good in 47 (94 %) cases, and there was agreement between colposcopist and video screener in 86 % of cases. The investigators stated that, if the technique had been used in a primary health care setting as a secondary screening method for women with low-grade cervical smear abnormalities, 61 % would have avoided referral for colposcopy. The investigators concluded that "before the technique can be implemented as part of the screening process, it needs to be evaluated in a larger series …" Other publications have described the technical performance of video colposcopy (e.g., Milbourne et al, 2005) and the use of video colposcopy as a research tool (Brown et al, 2005), as an educational tool (e.g., Walsh et al, 2004), in forensic investigations (e.g., Mears et al, 2003), and in colposcopy quality assurance protocols (e.g., Ferris et al, 2004). Regarding use of video colposcopy in quality assurance, Ferris et al concluded that "[c]olposcopy quality control by review of digitized colposcopic images in clinical trials warrants further evaluation if the accuracy can be improved."
Spectroscopy / Optical / Optoelectronic Detection Systems
The Luma cervical imaging system (MediSpectra, Inc., Lexington, MA) is an optical detection system approved by the FDA in March, 2006 as an adjunct to colposcopy to identify areas of the cervix with the highest likelihood of high-grade CIN on biopsy. The Luma system shines a light on the cervix and analyzes how different areas of the cervix respond to the light. The system produces a color map that distinguishes between healthy and potentially diseased tissue to indicate where biopsy samples should be taken.
In a pilot study, Huh and colleagues (2004) investigated the in-vivo optical detection of high-grade CIN. Cervical scanning devices collected intrinsic fluorescence and broadband white light spectra and video images from 604 women during routine colposcopy examinations. A statistically significant dataset was developed of intrinsic fluorescence and white light-induced cervical tissue spectra that was correlated to histopathologic determination. On the basis of a retrospective analysis of the acquired data, a classification algorithm was developed, validated, and optimized. Intrinsic fluorescence, back-scattered white light, and video imaging each contributed complementary information to diagnostic algorithms for high-grade cervical neoplasia. Over 10,000 measurements were made on colposcopically identified tissue from more than 500 subjects and were the basis for algorithm training and testing. Algorithm performance demonstrated a sensitivity of approximately 90 %. This performance was confirmed by various training methods. With the use of a multi-variate classification algorithm, optical detection is predicted to detect 33 % more high-grade CIN (2/3+) than colposcopy alone. The authors concluded that full cervix optical interrogation for the detection of high-grade CIN is feasible and appears capable of detecting more high-grade CIN than colposcopy alone.
A multi-center controlled trial (Alvarez et al, 2007) evaluated the performance of the Luma system as an adjunct to colposcopy among women (n = 193) referred for the evaluation of an abnormal cervical cytology result. Initial colposcopy identified 41 cases of CIN 2+ for a true positive (TP) rate of 21.2 %. Adjunctive use of the Luma system identified an additional 9 cases of CIN 2+ which corresponds to an incremental optical detection TP rate of 4.7 % (95 % CI: 2.2 % to 8.7 %). Adjunctive use of the Luma system resulted in a 22.0 % (95 % CI: 6.1 % to 37.8 %) relative gain in the number of women with CIN 2+ compared to colposcopy alone. The false-positive (FP) rate for initial colposcopy was 51.8 % (100 of 193 women). An additional 35 subjects had a Luma system-directed biopsy that was not diagnosed as CIN 2+, yielding an incremental FP rate of 18.1 % (95 % CI: 13.0 % to 24.3 %). The authors concluded that the adjunctive use of the Luma system with colposcopy provided a significant increase in the detection of CIN 2+ in women referred for the evaluation of abnormal cytology results.
There is insufficient evidence of the effectiveness of an optical detection system as an adjunct to colposcopy for in vivo identification and localization of cervical intraepithelial for cervical cancer screening or diagnosis. Furthermore, there are no recommendations or guidelines for its use from any professional medical society. Post-approval studies are currently underway to further assess the long-term efficacy of the Luma system.
A spectroscopy system may be referred to as an optical detection system. Spectroscopy emits light from a probe onto the cervix, allowing the examiner to objectively categorize tissues as either normal or diseased. Spectroscopy is based on the principle that epithelial tissues that are abnormal have different optical properties than normal tissues and that these optical differences can be used to determine whether a tissue is normal or abnormal. Devices that are currently under various stages of research and development for diagnostic purposes use various approaches, including: fluorescence spectroscopy, image analysis of visible images, infrared spectroscopy, Raman spectroscopy, white light elastic backscatter spectroscopy, or combinations of the different methods (Wright et al, 2002).
Wright et al (2002) stated that visual screening techniques include both low-technology approaches, such as direct visual inspection (DVI), and high-technology approaches, such as those that utilize electro-optical detectors to identify cervical cancer precursors and invasive cervical cancer. Simple visual screening techniques, such as DVI, consist of washing the cervix with a solution of 5 % acetic acid (e.g., vinegar) and then inspecting it using either the naked eye or with a low-power magnifying device to identify areas of aceto-whitening, which frequently correspond to cervical squamous intraepithelial lesions (SILs). The simple visual screening methods are being evaluated as an alternative to cytology in low-resource settings where screening using cervical cytology is not feasible. Multiple studies have shown DVI to have sensitivity similar to that of cervical cytology for identifying women with high-grade SIL but much lower specificity. The novel high-technology visual screening methods that utilize electro-optical sensors to identify cervical abnormalities are still in the developmental phases but offer considerable potential.
In a prospective observational study, Brown et al (2005) compared cervical impedance spectroscopy n the cervical epithelium of women with CIN and normal epithelium. A total of 87 women referred to colposcopy with a moderate or severely dyskaryotic smear were included in this study. A pencil probe incorporating 4 gold electrodes was used to measure an electrical impedance spectrum from cervical epithelium. Colposcopy examinations, including probe positioning, were recorded by video to allow for correlation between results obtained from colposcopic impression, histopathological examination of colposcopically directed punch biopsies and the impedance measurements. Cervical impedance derived parameters R, S and C were assessed to see if there was a significant difference in values obtained in CIN and normal squamous epithelium. Analysis was based upon matching the electrical components measured to those identified by cellular modeling as being most sensitive for pre-malignancy. From normal epithelium through CIN 1 to CIN 2/3, R decreased by a factor of 4.5, S increased by a factor of 2.5, but C remained unchanged. The authors concluded that cervical impedance spectroscopy provided a potentially promising screening tool with similar sensitivity and specificity to currently used screening tests, but with the potential advantage of providing instant results. Moreover, they stated that further work is currently being undertaken to improve the probe in its clinical use.
In a prospective, comparative, multi-center clinical study, Tidy et al (2013) examined if electrical impedance spectroscopy (EIS) improves the diagnostic accuracy of colposcopy when used as an adjunct. In phase-1, EIS was assessed against colposcopic impression and histopathology of the biopsies taken. In phase-2, a probability index and cut-off value for the detection of high-grade cervical intraepithelial neoplasia (HG-CIN, i.e., grade CIN2+) was derived to indicate sites for biopsy. Electrical impedance spectroscopy data collection and analyses were performed in real time and blinded to the clinician. The phase-2 data were analyzed using different cut-off values to assess performance of EIS as an adjunct. Main outcome measure was histologically confirmed HG-CIN (CIN2+). A total of 474 women were recruited: 214 were eligible for analysis in phase-1, and 215 were eligible in phase-2. The average age was 33.2 years (median age of 30.3 years, range of 20 to 64 years) and 48.5 % (208/429) had high-grade cytology. Using the cut-off from phase-1 the accuracy of colposcopic impression to detect HG-CIN when using EIS as an adjunct at the time of examination improved the PPV from 78.1 % (95 % CI: 67.5 to 86.4) to 91.5 %. Specificity was also increased from 83.5 % (95 % CI: 75.2 to 89.9) to 95.4 %, but sensitivity was significantly reduced from 73.6 % (95 % CI: 63.0 to 82.5) to 62.1 %, and the negative predictive value (NPV) was unchanged. The positive likelihood ratio for colposcopic impression alone was 4.46. This increased to 13.5 when EIS was used as an adjunct. The overall accuracy of colposcopy when used with EIS as an adjunct was assessed by varying the cut-off applied to a combined test index. Using a cut-off set to give the same sensitivity as colposcopy in phase-2, EIS increased the PPV to detect HG-CIN from 53.5 % (95 % CI: 45.0 to 61.8) to 67 %, and specificity increased from 38.5 % (95 %: CI 29.4 to 48.3) to 65.1 %. Negative predictive value was not significantly increased. Alternatively, applying a cut-off to give the same specificity as colposcopy alone increased EIS sensitivity from 88.5 % (95 % CI: 79.9 to 94.4) to 96.6 %, and NPV from 80.8 % (95 % CI: 67.5 to 90.4) to 93.3 %. Positive predictive value was not significantly increased. The receiver operator characteristic (ROC) to detect HG-CIN had an area under the curve (AUC) of 0.887 (95 % CI: 0.840 to 0.934). The authors concluded that EIS used as an adjunct to colposcopy improves colposcopic performance; and the addition of EIS could lead to more appropriate patient management with lower intervention rates.
An UpToDate review on “Cervical cancer screening tests: Evidence of effectiveness” (Sirovich et al, 2014) does not mention the use of spectroscopy/optical detection system as a screening tool. Furthermore, the National Comprehensive Cancer Network’s clinical practice guideline on “Cervical cancer” (Version 1.2014) does not mention spectroscopy/optical detection systems as screening tools.
In a systematic review and meta-analysis, Yang and colleagues (2018) examined the diagnostic accuracy of a real-time optoelectronic device (TruScreen) for uterine cervical cancer screening. On the basis of Preferred Reporting Items for Systematic Reviews and Meta-analyses (the PRISMA statement), these researchers searched PubMed, Embase, the Cochrane Library, CNKI, CBM, and WanFang Data using medical subject headings (MeSH) and text words. Title/abstract screening, full text check, data extraction, and methodological quality assessment (with the QUADAS-2 tool) were performed by 2 reviewers independently. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), the summary receiver operator characteristic curve, and the area under the curve (AUC) were analyzed with Meta-DiSc software. Statistical heterogeneity was evaluated by Cochran's Q test and I, meta-regression was conducted based on patient type, and the possibility of publication bias was evaluated using Deeks funnel plot in Stata software. Of 293 publications, 9 met inclusion criteria. These studies included a total of 2,730 patients and 567 cervical intra-epithelial neoplasia. The pooled test characteristics for the TruScreen were as follows: sensitivity 76 % (95 % CI: 73 % to 80 %), specificity 69 % (95 % CI: 67 % to 71 %), PLR 2.30 (95 % CI: 1.59 to 3.33), and NLR 0.34 (95 % CI: 0.23 to 0.51). The corresponding pooled DOR was 7.03 (95 % CI: 3.40 to 14.55). The AUC was 0.7859 (Q = 0.7236). The authors concluded that the diagnostic value of this real-time optoelectronic device was moderate at best. These researchers noted that given that the number of included studies in the meta-analysis was relatively small and all studies were conducted in China, the findings of this study could not be generalized to other populations and should be interpreted with caution.
The authors stated that the findings of this meta-analysis should be interpreted in light of the following limitations. First, these investigators only included 9 studies, all of which were conducted in China. Second, due to the limited number of patients, these researchers did not analyze the performance of the TruScreen device for detection of cervical intraepithelial neoplasia (CIN) II or higher. Third, these researchers did not include “gray” literature, unpublished studies, or research abstracts from meeting proceedings. Such studies were not commonly subjected to peer-review and they provided limited data. However, by choosing to eliminate these studies, the authors might have over-looked potentially relevant studies. Fourth, data from the 9 studies were collected in advanced areas and hospitals where there were well-trained medical doctors. If the study were conducted in remote mountain/village areas by a part-time medical assistant, the conclusions may have been different. Furthermore, these investigators stated that in the process of carrying out the meta-analysis, they found that some studies only performed the gold standard test on patients with a positive cervical cytology result or a positive index test result. This may have led to partial verification bias or work-up bias; future researchers should remain alert to this kind of bias.
Furthermore, National Comprehensive Cancer Network’s clinical practice guideline on “Cervical cancer” (Version 3.2019) does not mention the use of an optoelectronic device as a screening tool.
In summary, as a consequence of the lack of well-designed studies, there is insufficient evidence to support the use of spectroscopy/optical/optoelectronic detection systems as a primary stand-alone or as an adjunct to standard screening techniques for the detection of cervical cancer.
Resolve™
Colposcopy is a diagnostic procedure in which a colposcope is used to provide an illuminated, magnified view of the cervix, vagina, and vulva to detect malignant and pre-malignant epithelium. Malignant and pre-malignant epithelium have specific macroscopic characteristics relating to contour, color, and vascular pattern that can be identified by the colposcopist for directed biopsy. Colposcopy is the "gold standard" diagnostic tool in the U.S. for diagnosing cervical dysplasia following abnormal cytology.
The Resolve laboratory testing kit (Gynecor, Glen Allen, VA) is a new colposcopic method that obtains endocervical samples using cytobrushes. The kit contains 2 cytobrushes and 2 vials of fixative. The first cytobrush is used to clear mucus from the cervix and the second cytobrush is used to abrade cells from the endocervix. The fixative enables both cytology and histology to be run on both vials. HPV is also tested from the same specimen. If HPV is detected, genotyping by PCR is also reported.
There is insufficient evidence of the effectiveness of the Resolve laboratory testing kit for cervical cancer screening or diagnosis. How this method compares with conventional colposcopy and cytology using quantified values of sensitivity and specificity awaits results from randomized controlled trials and/or recommendations from leading national medical organizations.
Methylation Markers
Studies of cervical cancer and its immediate precursor, cervical intra-epithelial neoplasia 3, have identified genes that often show aberrant DNA methylation and thus represent candidate early detection markers. Wentzensen et al (2009) identified the most promising methylation marker candidates for cervical cancer early detection. A systematic literature review was performed in Medline and weighted average frequencies for methylated genes stratified by tissue source and methods used were computed. A total of 51 studies were identified analyzing 68 different genes for methylation in 4,376 specimens across all stages of cervical carcinogenesis. A total of 15 genes (DAPK1, RASSF1, CDH1, CDKN2A, MGMT, RARB, APC, FHIT, MLH1, TIMP3, GSTP1, CADM1, CDH13, HIC1, and TERT) have been analyzed in 5 or more studies. The published data on these genes is highly heterogeneous; 7 genes (CDH1, FHIT, TERT, CDH13, MGMT, TIMP3, and HIC1) had a reported range of methylation frequencies in cervical cancers of greater than 60 % between studies. Stratification by analysis method did not resolve the heterogeneity. Three markers (DAPK1, CADM1, and RARB) showed elevated methylation in cervical cancers consistently across studies. The authors concluded that there is currently no methylation marker that can be readily translated for use in cervical cancer screening or triage settings. They stated that large, well-conducted methylation profiling studies of cervical carcinogenesis could yield new candidates that are more specific for HPV-related carcinogenesis. New candidate markers need to be thoroughly validated in highly standardized assays.
The Ikonisys oncoFISH Cervical Test
According to Ikonisys Clinical Laboratories, the oncoFISH® cervical test is a qualitative fluorescence in-situ hybridization (FISH) test for determining the acquisition of specific chromosomal aneuploidies within the 3q26 region in cytological specimens revealing LSIL. Until now, routine testing for 3q gain was not feasible because assessment required analysis of a large number of stained, squamous cell nuclei – impractical for manual methods. By using the Ikoniscope Digital Microscopy System to automate analysis, the oncoFISH cervical test makes testing for 3q gain a practical reality. The test is performed on cervico-vaginal cytology specimens, identical to those used for Pap and HPV testing. It evaluates amplification of the 3q26 region by use of 2 FISH probes, one for the 3q26 locus and a control probe. Enumeration and comparison of the 3q26 and control probes, in conjunction with the nuclear morphology, result in a 3q copy number for each of the nuclei analyzed. Results of the oncoFISH cervical test are intended for use with other clinical findings for further evaluation and monitoring of cervical dysplasia in women with LSIL Pap results. The oncoFISH cervical test is a laboratory developed test and is intended to supplement, and not replace or alter the current standards of practice used for the clinical management of women undergoing evaluation for cervical dysplastic lesions. The oncoFISH cervical test results should be considered by the clinician in the context of other testing when formulating clinical management.
Caraway et al (2008) noted that chromosomal aberrations have been documented in cervical carcinomas, especially chromosome 3q. The human telomerase RNA gene (hTERC) is located in the chromosome 3q26 region, and its product, telomerase, is involved in the maintenance of chromosome length and stability. Up-regulation of telomerase is in general associated with tumorigenesis. In this study, cervico-vaginal specimens were analyzed by FISH for gain of chromosome 3q26 containing hTERC, and FISH findings were compared with the cytologic and histologic diagnoses. Slides prepared from 66 liquid-based preparations from cervical specimens with cytologic diagnoses of negative for SIL or malignancy (NILM, n = 4), atypical squamous cells of undetermined significance (ASC-US, n = 15), LSIL (n = 20), HSIL (n = 24), or cervical squamous cell carcinoma (SCCA, n = 3) were analyzed for aberrations of 3q26 using a commercially available 2-color FISH probe. The results of the cytologic analysis and those of concurrent or subsequent biopsies, when available, were compared with the FISH-detected 3q26 abnormalities. The Wilcoxon rank-sum test was used to assess associations between 3q26 gains and diagnoses. Gain of 3q26 was significantly associated with the cytologic diagnosis (p < 0.0001). Patients with HSIL or SCCA cytology diagnoses had significantly higher percentages of cells with 3q26 gain than did patients with NILM or ASC-US cytologic diagnoses. The authors concluded that FISH can be performed on cervico-vaginal liquid-based preparations to detect gain of 3q26; gain of 3q26 is associated with HSIL and SCCA. They stated that this test may be an adjunct to cytology screening, especially high-risk patients. This study did not have enough correlative data to be useful.
Seppo et al (2009) evaluated an automated FISH assay for detection of 3q gain in liquid cytology samples as a potential tool for risk stratification and triaging. Slides prepared from 257 liquid cytology specimens (97 negative, 135 LSIL and 25 HSIL) were hybridized with a single-copy probe for the chromosome 3q26 region and a probe for the centromeric alpha-repeat sequence of chromosome 7, using standard FISH methods. Using automated analysis, the total number of nuclei and the number of nuclei with greater than 2 signals for 3q26 were determined, using a 20x objective. The nuclei were rank ordered based on number of 3q26 FISH signals. The 800 nuclei with the highest number of signals were scored using both FISH probes and nuclei with increased numbers of 3q signals were enumerated. Analysis of 257 specimens demonstrated that a fully automated FISH scoring system can detect 3q gain in liquid cytology samples. The authors concluded that a fully automated method for determination of 3q gain in liquid cytology may be the assay necessary to implement routine testing; and they stated that additional studies to validate the utility of this technology are needed.
Policht et al (2010) evaluated 35 genomic regions associated with cervical disease and selected those which were found to have the highest frequency of aberration for use as probes in FISH. The frequency of gains and losses using FISH were assessed in these 35 regions on 30 paraffin-embedded cervical biopsy specimens. Based on this assessment, 6 candidate fluorescently labeled probes (8q24, Xp22, 20q13, 3p14, 3q26, CEP15) were selected for additional testing on a set of 106 cervical biopsy specimens diagnosed as normal, CIN1, CIN2, CIN3, and SCC. The data were analyzed on the basis of signal mean, % change of signal mean between histological categories, and % positivity. The study revealed that the chromosomal regions with the highest frequency of copy number gains and highest combined sensitivity and specificity in high-grade cervical disease were 8q24 and 3q26. The cytological application of these 2 probes was then evaluated on 118 ThinPrep samples diagnosed as normal, ASCUS, LSIL, HSIL and cancer to determine utility as a tool for less invasive screening. Using gains of either 8q24 or 3q26 as a positivity criterion yielded specificity (normal + LSIL + ASCUS) of 81.0 % and sensitivity (HSIL + cancer) of 92.3 % based on a threshold of 4 positive cells. The authors concluded that the application of a FISH assay comprised of chromosomal probes 8q24 and 3q26 to cervical cytology specimens confirmed the positive correlation between increasing dysplasia and copy gains and showed promise as a marker in cervical disease progression.
Verri and colleagues (2011) stated that studies have demonstrated a correlation between the gain in 3q26 copy number and the severity and stage of cervical disease progression. A recent study has examined the potential of using a measure of 3q26 gain as a predictor of regression, persistence, or progression of LSIL of the cervix. The case described in this report documented a marked progression in both the severity and extent of this patient's lesion from atypical squamous cells on cytology to biopsy established CIN2-CIN3 over the span of 1 year. The initial gain of at least 5 copies of 3q26 in only 3 nuclei in this patient's first cervical smear may be an indication of the significance and sensitivity of this degree of gain, even in a small number of cells at a low level of disease, and may suggest the potential of predicting the progression of the lesion. The subsequent gain of at least 5 copies of 3q26 1 year later in the very large number of 264 nuclei may reflect both the severity and extent of disease progression. Nevertheless, since it is not possible to exclude the possibility that a high-grade CIN already existed at the time of the initial cytology, the presence of the 3q26 gain, even in a small number of cells, may also serve as an indicator of the possible presence of a high-grade lesion in those cervical specimens in which a definitive cytological diagnosis is not or cannot be made. The authors concluded that this case report supported the findings of other investigators on the potential utility of using 3q26 gain in predicting, at an early stage, the progression or non-progression of low-grade pre-neoplastic lesions of the cervix.
Rodolakis and associates (2012) examined if 3q26 gain can predict which LSILs and ASC-USs will progress to HSIL. Liquid cytology specimens of LSIL and ASC-US from 73 women were examined using FISH for the detection of 3q26 gain. All women underwent colposcopy and biopsy at the initial visit and 40 of them with histology showing CIN 1 or HPV infection (koilocytosis) were included in the study. They were re-evaluated with liquid cytology, colposcopy, and biopsy after a median follow-up of 17.5 months. A total of 40 cases were analyzed (31 LSILs and 9 ASCUSs). Of these cases, 8 (20 %; 6 LSILs and 2 ASCUSs) were positive and 32 (80 %) were negative for 3q26 gain according to FISH. Three of the 8 positive women (38 %) progressed to HSIL/CIN 2 or worse, whereas none of the 32 negative women did so. 3q26 gain could predict progression with a negative-predictive value of 100 % (95 % confidence interval: 89.1 % to 100 %). In addition, women positive for 3q26 gain had a significantly lower regression rate compared with negative women (p = 0.009). The authors concluded that in this first prospective study, 3q26 gain in LSIL/ASCUS cytology exhibited an impressive negative predictive value for progression to HSIL/CIN 2 or worse. They stated that 3q26 gain may be useful in stratifying patients' risk for progression and possibly alter management and reduce cost of follow-up.
Currently, there is insufficient evidence regarding the clinical value of the oncoFISH cervical test. Furthermore, there are no guidelines from leading medical professional organizations or public health agencies that recommend FISH measurement of 3q26 in cervical cancer screening.
Fluorescence In-Situ Hybridization (FISH) Testing
Earley et al (2014) examined the diagnostic performance of fluorescence in-situ hybridization (FISH) tests on cervical cytology for precancerous lesions or cancer on cervical histology. These researchers performed a search in MEDLINE, the Cochrane Central Register of Controlled Trials, and Scopus through September 3, 2013. A total of 11 studies examined FISH tests for telomerase RNA component gene (TERC), myelocytomatosis oncogene (MYC), or HPV type 16 or 18 in samples exhibiting ASC-US or LSIL. None examined HPV-positive, cytologically normal samples. These investigators extracted data on the sensitivity and specificity for high-grade cervical intraepithelial neoplasia (CIN 2+ or CIN 3+). Fluorescence in-situ hybridization test probes and thresholds varied across studies. Included populations were convenience samples. Only 1 study testing for TERC specified HPV status. In meta-analysis, FISH for TERC in LSIL (9 studies, 1,082 cases) had a summary sensitivity of 0.76 (95 % CI: 0.63 to 0.85) and a summary specificity of 0.78 (95 % CI: 0.57 to 0.91) for CIN 2+. Fluorescence in-situ hybridization for TERC in ASC-US (3 studies, 839 cases) showed sensitivities ranging from 0.75 to 1.00 and specificities from 0.87 to 0.93 for CIN 2+. For CIN 3+, sensitivity and specificity appeared similar, although a small number of studies preclude firm conclusions. For FISH tests for HPV, these researchers found only few studies with small sample sizes. The authors concluded that the evidence on FISH testing is limited given the small number of studies for each cytology subgroup and the lack of studies in well-defined screening contexts stratifying participants by HPV status.
An AHRQ assessment on fluorescent in situ hybridization or other in situ hybridization of uterine cervical cells to predict precancer and cancer (Uhlig, et al, 2013) concluded: “Overall, the evidence of the analytic and clinical validity of ISH tests in screening for cervical cancer was limited. Further research is needed to standardize techniques, compare clinical validity, thresholds, and combinations across different ISH tests, and compare the clinical utility of combinations of probes as add-on tests to HPV and cytology tests.”
Furthermore, an UpToDate review on “Invasive cervical cancer: Epidemiology, risk factors, clinical manifestations, and diagnosis” (Frumovitz, 2015) and National Comprehensive Cancer Network’s clinical practice guideline on “Cervical cancer” (Version 2.2015) do not mention fluorescence in-situ hybridization/FISH as a diagnostic tool.
p16/Ki-67 Dual Staining for Triaging High Risk HPV Strains
Ravarino and colleagues (2012) noted that cytologic findings of glandular lesions of the cervix uteri are often difficult to evaluate. These researchers examined the usefulness of CINtec PLUS p16/Ki-67 double-stain (mtm laboratories, Heidelberg, Germany) for the diagnosis of glandular lesions. The study included 47 abnormal results on liquid-based cytologic tests with a subsequent histologic diagnosis of adenocarcinoma in-situ or with early invasion, and 16 samples with negative results on follow-up. All samples were stained with CINtec PLUS p16/Ki-67 double-stain. Of the neoplastic samples, 7 were excluded because of insufficient residual cellularity or loss of neoplastic cells. Of the samples that were adequate, 92.5 % were stained with CINtec PLUS, whereas 7.5 % were judged inconclusive. All inconclusive cases were at least 3 years old. Of the 16 negative samples, 15 (93.8 %) stained negative and only 1 (6.2 %) showed several positive clusters of cells. The authors concluded that the findings of this study showed that CINtec PLUS immunocytochemistry may be a useful tool for the diagnosis of glandular lesions of the cervix uteri and may reduce the risk of false negatives as well as the number of uncertain borderline reports. Moreover, these researchers stated that the interpretation of the immuno-stains, however, may differ slightly between squamous and glandular lesions and always needs to take into account the morphology of the stained cells.
The authors stated that this study showed that CINtec PLUS immunocytochemistry may be useful also for the cytologic diagnosis of glandular lesions of the cervix uteri. Among neoplastic samples, 92.5 % expressed CINtec PLUS, whereas 93.8 % of the negative samples did not. The few cases that were judged inconclusive were older samples that had been conserved for more than 2 years at room temperature. In fact this, as well as the poor cellularity of some samples that had been used in previous studies, was a limitation of this study. In some cases, only a few small residual neoplastic sheets were present and therefore more difficult to evaluate.
Chen and colleagues (2016) reviewed studies investigating the diagnostic performance of p16/Ki-67 dual stain for triage of women with abnormal Pap tests. They conducted a systematic review and meta-analysis of diagnostic test accuracy studies. These researchers followed the protocol of systematic review of diagnostic accuracy studies. They searched PubMed, The Cochrane Library, BioMed Central, and ClinicalTrials.gov for relevant studies, and included research that assessed the accuracy of p16/Ki-67 dual stain and high-risk HPV testing for triage of abnormal Pap smears. Review articles and studies that provided insufficient data to construct 2.2 tables were excluded. Data synthesis was conducted using a random-effects model. Main outcome measures were sensitivity and specificity. In 7 studies encompassing 2,628 patients, the pooled sensitivity and specificity of p16/Ki-67 for triage of abnormal Pap smear results were 0.91 (95 % CI: 0.89 to 0.93) and 0.64 (95 % CI: 0.62 to 0.66), respectively. No study used a case-control design. A subgroup analysis involving liquid-based cytology showed a sensitivity of 0.91 (95 % CI: 0.89 to 0.93) and specificity of 0.64 (95 % CI: 0.61 to 0.66). The authors concluded that this meta-analysis of p16/Ki-67 dual stain studies showed that the test achieved high sensitivity and moderate specificity for p16/Ki-67 immunocytochemistry for high-grade squamous intraepithelial lesion and cervical cancer. They suggested that p16/Ki-67 dual stain might be a reliable ancillary method identifying high-grade squamous intraepithelial lesions in women with abnormal Pap tests. The authors stated that a major drawback of this study was that no study in the meta-analysis examined the accuracy of the p16/Ki-67 dual stain for interpretation of glandular neoplasms.
Wright et al (2017) assessed the performance of p16/Ki-67 dual-stained cytology for triaging HPV-positive women undergoing primary HPV screening. All women greater than or equal to 25years with valid cervical biopsy and cobas HPV Test results from the cross-sectional phase of ATHENA who were referred to colposcopy (n = 7,727) were eligible for enrolment. p16/Ki-67 dual-stained cytology was retrospectively performed on residual cytologic material collected into a 2nd liquid-based cytology vial during the ATHENA enrolment visit. The diagnostic performance of dual-stained cytology, with or without HPV16/18 genotyping, for the detection of biopsy-confirmed cervical intraepithelial neoplasia grade 3 or worse (CIN3+) was determined and compared to Pap cytology. Furthermore, the number of colposcopies required per CIN3+ detected was determined. The investigators found that dual-stained cytology was significantly more sensitive than Pap cytology (74.9 % versus 51.9 %; p < 0.0001) for triaging HPV-positive women, whereas specificity was comparable (74.1 % versus 75.0 %; p = 0.3198). Referral of all HPV16/18 positive women combined with dual-stained cytology triage of women positive for 12 "other" HPV genotypes provided the highest sensitivity for CIN3+ (86.8 %; 95 % CI: 81.9 to 90.8). A similar strategy but using Pap cytology for the triage of women positive for 12 "other" HPV genotypes was less sensitive (78.2 %; 95 % CI: 72.5 to 83.2; p = 0.0003), but required a similar number of colposcopies per CIN3+ detected. The investigators concluded that 16/Ki-67 dual-stained cytology, either alone or combined with HPV16/18 genotyping, represents a promising approach as a sensitive and efficient triage for colposcopy of HPV-positive women when primary HPV screening is utilized.
Consensus Recommendations from the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology (Darragh et al, 2012) stated: "On the basis of final literature review and data extractions, we concluded that only p16, a biomarker that is recognized in the context of HPV biology to reflect the activation of E6/E7–driven cell proliferation, had sufficient evidence on which to make recommendations regarding use in LAT squamous lesions. ProEx C and Ki-67 (Mib1) had similar trending data, but the literature was insufficient to make an independent recommendation for use, alone or in combination. Individual institutions might opt to use these other markers in cases with equivocal p16 IHC staining or as an adjunct, given that both have cleaner nuclear staining. However, the accumulated evidence was insufficient to make an independent recommendation for use of any additional biomarker, alone or in combination."
More recent guidelines from the French National Heath Authority (HAS, 2019) concluded: "In view of the available data, the use of p16/Ki67 dual immunostaining for primary screening or as a triage test following a positive HPV test is not recommended.
An UpToDate review on “Screening for cervical cancer” (Feldman et al, 2017 ) does not mention p16/Ki-67 dual staining as a screening/diagnostic tool. In a discussion of future directions in cervical cancer screening, In an UpToDate chapter on "Human papillomavirus testing of the cervix: Management of abnormal results", Einstein (2019) stated that: "In addition to cervical cytology and HPV testing, there are tests to evaluate cervical biopsy specimens that aid pathologists in their diagnoses, such as immunostaining for p16INK4a/Ki-67. . . . Some of these tests will likely be considered in future management guidelines."
Furthermore, National Comprehensive Cancer network’s clinical practice guideline on “Cervical cancer” (Version 1.2017) does not mention p16/Ki-67 dual staining as a screening/diagnostic tool. The NCCN guidelines panel for cervical cancer screening endorses guidelines from the ASCCP (Saslow et al, 2012) and consensus recommendations from Massad et al (2013).
- SCC-Ag: range sensitivity of 78.6 % to 81.2 %, specificity of 74 % to 100 %;
- M-CSF: sensitivity of 68 % to 87.7 %, specificity of 64.7 % to 94 %;
- VEGF: sensitivity of 56 % to 83.5 %, specificity of 74.6 % to 96 %;
- microRNA: sensitivity of 52.9 % to 67.3 %, specificity of 76.4 % to 94.4 %;
- p16INKa / ki-67: sensitivity of 50 % to 100 %, specificity of 39 % to 90.4 %;
- HPV E6/E7/mRNA: sensitivity of 65 % to 100 %, specificity of 42.7 & to 90.2 %, and
- DNA methylation: sensitivity of 59.7 % to 92.9 %, specificity of 67 % to 9%.
The authors concluded that the reported test performance and the receiving operating characteristics curves implied that implementation of p16ink4a/ki-67 assay as a triage for HPV positive women to be used at one visit with subsequent cryotherapy treatment is feasible.
The authors stated that this systematic review presented the latest developments in the field of SCC Ag, M-CSF, VEGF, miRNA (miR-9), p16INKa / ki-67, HPV E6/E7 mRNA and DNA methylation tests accuracy. These researchers included relatively adequate number of articles published in different countries employing large number of study participants; however, these findings should be interpreted in light of a few shortcomings. The main drawback was lack of studies that employed similar and well-defined population with same cervical pathology characteristics; therefore, this review suffered from heterogeneity of studies that made it difficult to pool the performance characteristics of each of the tested assays. Furthermore, the use of histologically confirmed CIN2+ endpoint when evaluating the test accuracy represented a challenge because of the regression (false-positive) or progression (false-negative) of many confirmed lesions. Moreover, confining the inclusion criteria to include only articles published in English would also mean missing some of the relevant studies; thus, reducing the accuracy of these findings.
Safaeian and associates (2021) noted that an increase in HPV test volumes is expected in the near future as HPV–based screening protocols are expected to become more broadly adopted. The IMproving Primary screening And Colposcopy Triage (IMPACT) Trial, a prospective, multi-center U.S. cervical cancer screening trial, was carried out to obtain FDA approvals for the new high-throughput cobas HPV for use on the cobas 6800/8800 Systems (cobas HPV) for detecting cervical pre-cancer and cancer (cervical intraepithelial neoplasia of grade 2 or worse [greater than or equal to CIN2] and grade 3 or worse, [greater than or equal to CIN3]). These researchers presented the baseline demographics, HPV, cervical cytology and histopathologic results. Furthermore, the baseline and 1-years risks of greater than or equal to CIN2 and greater than or equal to CIN3 associated with HPV results were reported. A total of 35,263 women aged 25 to 65 years undergoing routine screening were enrolled; liquid-based cytology and 2 high-risk HPV PCR-based tests were carried out. Women with abnormal Pap cytology, women positive for high-risk HPV by either of the 2 HPV tests, and a random subset of women negative by Pap cytology and the 2 HPV tests were referred to colposcopy/cervical biopsy. Women who did not meet the study endpoint were eligible for the 1-year follow-up study phase. Verification bias-adjusted cervical disease prevalence and risks and 95 % CIs were computed. The prevalence of ASC-US and greater than ASC-US cytology were 6.5 % and 3.2 %, respectively. Prevalence of high-risk HPV, HPV16, and HPV18 base on the new cobas HPV test were 15.1 %, 3.1 %, and 1.4 %, respectively. Both cytologic abnormalities and HPV positivity declined with increasing age. Among women who had a colposcopy/biopsy, prevalence of greater than or equal to CIN2 and greater than or equal to CIN3 were 8.8 % and 3.6 %, respectively. The baseline and 1-year cumulative risks for greater than or equal to CIN3 were 13.6 % and 16.9 %, respectively, in HPV16-postive women. HPV-negative women had the lowest 1-year cumulative risk for greater than or equal to CIN3 (0.06 %). The authors concluded that the contemporary age-specific prevalence of HPV (including HPV16 and HPV18), cytologic abnormalities, and CIN in a large U.S. cervical cancer screening population provided benchmarks for health care policy, screening programs, and for laboratories and clinicians. These researchers stated that a drawback of the IMPACT Trial was that follow-up of women who underwent colposcopy at baseline was only 1 year, as opposed to 3 years as in the ATHENA and Onclarity Trials.
UpToDate reviews on “Screening for cervical cancer in resource-rich settings” (Feldman et al, 2021) and “Screening for cervical cancer in resource-limited settings” (Denny, 2021) do not mention p16INKa / ki-67 / dual staining as a management option.
Furthermore, National Comprehensive Cancer Network’s clinical practice guideline on “Cervical cancer” (Version 1.2021) does not mention p16INKa / ki-67 / dual staining.
Wright et al (2022) noted that triage strategies are needed for primary human papillomavirus (HPV)-based cervical cancer screening to identify women requiring colposcopy/biopsy. In a prospective, observational study, these researchers examined the performance of p16/Ki-67 dual-stained (DS) immunocytochemistry to triage HPV-positive women and compared it to cytology, with or without HPV16/18 genotyping. This trial enrolled 35,263 women aged 25 to 65 years at 32 U.S. sites. Cervical samples had HPV and cytology testing, with colposcopy/biopsy for women with positive tests. Women without cervical intraepithelial neoplasia Grade 2 or worse (greater than or equal to CIN2) at baseline (n = 3,876) were re-tested after 1 year. A total of 4,927 HPV-positive women with valid DS results were included in this analysis. DS sensitivity for greater than or equal to CIN2 and greater than or equal to CIN3 at baseline was 91.2 % (95 % confidence interval [CI]: 86.8 % to 94.2 %) and 91.9 % (95 % CI: 86.1 % to 95.4 %), respectively, in HPV16/18-positive women and 83.0 % (95 % CI: 78.4 % to 86.8 %) and 86.0 % (95 % CI: 77.5 % to 91.6 %) in women with 12 "other" genotypes. Using DS alone to triage HPV-positive women showed significantly higher sensitivity and specificity than HPV16/18 genotyping with cytology triage of 12 "other" genotypes, and substantially higher sensitivity but lower specificity than using cytology alone. The risk of greater than or equal to CIN2 was significantly lower in HPV-positive, DS-negative women (3.6 %; 95 % CI: 2.9 % to 4.4 %), compared to triage-negative women using HPV16/18 genotyping with cytology for 12 "other" genotypes (7.4 %; 95 % CI: 6.4 % to 8.5 %; p < 0.0001) or cytology alone (7.5 % ; 95 % CI: 6.7 % to 8.4 %; p < 0.0001). DS showed better risk stratification than cytology-based strategies and provided high reassurance against pre-cancers both at baseline and at 1-year follow-up, irrespective of the HPV genotype. DS allowed for the safe triage of primary screening HPV-positive women. These researchers stated that the main drawback of this study was the fact that the study follow-up was limited to 1 year; thus, the assessment of the negative disease prediction of a negative DS for a period longer than 1 year could not be made.
Li et al (2022) stated that CINtec PLUS p16/Ki-67 DS cytology is an alternative test to cytology in triaging HPV-positive women. Dalton p16/Ki-67 Dual Stain kit employs the similar immunocytochemical detection and operating procedures with CINtec PLUS; however, its accuracy and effectiveness in triaging HPV-positive women need to be examined. A total of 717 HPV-positive specimens of cervical exfoliated cells were included. Cytology, Dalton, and CINtec PLUS were subsequently performed, and 2 DS tests were separately completed in each of the same specimens. The results of 2 DS tests were head-to-head compared, and their effectiveness to identify high-grade CIN were evaluated, using histopathology of biopsy as the golden standard. The overall positive rate of 2 DS tests were 28.31 % for Dalton and 33.89 % for CINtec PLUS (p < 0.05); both rose with the increased severity of histopathological and cytological abnormalities. Compared to CINtec PLUS, the positive rate of Dalton was significantly lower in the normal histopathology group (p < 0.05) and lower, but not significantly, in mild abnormal histopathology and cytology NILM and LSIL groups. Two DS tests showed a good consistency (Kappa value, 0.63; 95 % CI: 0.557 to 0.688), with 100 % of consistency in the cytology HSIL group. Inconsistency occurred mainly in the cytology NILM and LSIL groups, with more Dalton negative but CINtec PLUS positive. Compared to CINtec PLUS, Dalton showed similar sensitivity (94.59 % versus 91.89 %), but significantly higher specificity (75.29 % versus 69.26 %, p = 0.013) and accuracy (76.29 % versus 70.43 %, p = 0.012), with a larger AUC of 0.849 (95 % CI: 0.800 to 0.899) for identifying CIN3+. The similar results were observed when identifying CIN2+. The author s concluded that Dalton presented the lower false positive rate and better effectiveness in identifying high-grade CIN than CINtec PLUS, suggesting that Dalton may be superior to CINtec PLUS and an alternative technique for triaging primary HPV-positive women in cervical cancer screening.
Mazurec et al (2023) stated that in the context of primary HPV cervical cancer screening, the identification of minor screening abnormalities necessitates triage tests to optimize management and mitigate over-treatment. Currently, reflex cytology and reflex p16/Ki67 dual-stain (DS) are under scrutiny for their applicability in primary HPV-based screening. However, there remains a dearth of comprehensive data for comparing their performance. Among 30,066 results from liquid-based cervical cancer screening tests, a cohort of 332 cases was meticulously selected based on available HR-HPV test results, limited genotyping for HPV 16 and 18, liquid-based cytology, DS, and histology outcomes from standardized colposcopy with biopsy. For cases positive for 12 other high-risk HPV genotypes, 3 retrospective triage approaches were analyzed. These investigators calculated the PPV for the detection of HSIL+. Both triage models employing DS (reflex cytology followed by DS and reflex DS alone in all cases) exhibited significantly higher PPV for HSIL+ compared to the strategy with reflex cytology alone (35.9 %/33.3 % versus 18.8 %; p < 0.0001). Furthermore, these DS-based models showed higher NPV (100 %/96.2 % versus 69.2 %; p = 0.0024/0.0079). In the DS-inclusive models, fewer colposcopies were necessitated (103/102 versus 154), and fewer cases of HSIL+ were overlooked (0/3 versus 8). The authors concluded that these findings suggested that p16/Ki67 dual-stain, either as a standalone or combined triage test, holds promise for the effective detection of HSIL+ in patients with minor screening abnormalities in primary HPV-based cervical cancer screening. Moreover, these researchers stated that future studies with larger sample sizes and multi-center designs are needed to confirm these findings.
The authors stated that this study had several drawbacks, such as being a post-hoc analysis. Not all patients with abnormal screening results underwent colposcopy with a biopsy at the center. Due to the different histologic terminology and/or colposcopic protocols and/or the lack of p16 stain in cervical histologic specimens, the study did not incorporate the results of colposcopic biopsies performed outside the facility. One of the other main drawbacks was the sample size, which may have affected the accuracy of the PPV estimate. Also ,this trial was carried out in a single, private-funds-based center, and the results may not be generalizable to other populations.
Clarke et al (2024) noted that the Enduring Consensus Cervical Cancer Screening and Management Guidelines Committee developed recommendations for dual stain (DS) testing with CINtec PLUS Cytology for use of DS to triage high-risk HPV-positive results. Risks of CIN grade-3 or worse were calculated according to DS results among individuals testing HPV-positive using data from the Kaiser Permanente Northern California cohort and the STudying Risk to Improve DisparitiES study in Mississippi. Management recommendations were based on clinical action thresholds developed for the 2019 ASCCP risk-based management consensus guidelines. Resource usage metrics were calculated to support decision-making. Risk estimates in relation to clinical action thresholds were reviewed and used as the basis for draft recommendations. After an open comment period, recommendations were finalized and ratified through a vote by the Consensus Stakeholder Group. For triage of positive HPV results from screening with primary HPV testing (with or without genotyping) or with cytology co-testing, colposcopy is recommended for individuals testing DS-positive. One-year follow-up with HPV-based testing is recommended for individuals testing DS-negative, except for HPV16- and HPV18-positive results, or high-grade cytology in co-testing, where immediate colposcopy referral is recommended. Risk estimates were similar between the Kaiser Permanente Northern California and STudying Risk to Improve DisparitiES populations. In general, resource usage metrics suggested that compared with cytology, DS required fewer colposcopies and detected CIN grade-3 or worse earlier. The authors concluded that dual stain testing with CINtec PLUS Cytology was acceptable for triage of HPV-positive test results; and risk estimates were portable across different populations. Moreover, these researchers stated that future opportunities exist to examine the accuracy of DS in primary screening settings, and of DS in combination with novel strategies such as extended genotyping and automated approaches.
Quh et al (2024) noted that cervical cancer, primarily caused by HR-HPV types 16 and 18, is a major health concern worldwide. Persistent HR-HPV infection can progress from reversible pre-cancerous lesions to invasive cervical cancer, which is driven by the oncogenic activity of HPV genes, especially E6 and E7. Traditional screening methods, including cytology and HPV testing, have limited sensitivity and specificity. These investigators examined the use of p16/Ki-67 dual-staining cytology for cervical cancer screening. This advanced immunocytochemical method allows for simultaneously detecting p16 and Ki-67 proteins within cervical epithelial cells, offering a more specific approach for triaging HPV-positive women. Dual staining and traditional methods were compared, showing their high sensitivity and NPV but low specificity. The increased sensitivity of dual staining results in higher detection rates of CIN2+ lesions, which is crucial for preventing cervical cancer progression. However, its low specificity may lead to increased false-positive results and unnecessary biopsies. The implications of integrating dual staining into contemporary screening strategies, especially considering the evolving landscape of HPV vaccination and changes in HPV genotype prevalence, were also discussed. The authors concluded that P16/Ki-67 dual staining enhanced the detection of pre-cancerous lesions in HPV-positive individuals, improving risk stratification, and reducing unnecessary procedures. While it offers increased sensitivity, challenges such as false positives and specificity need balancing to avoid over-treatment. Its integration into clinical practice requires adaptation to diverse patient populations and healthcare settings, considering cost and accessibility. These researchers stated that future efforts should focus on refining its application, supported by evolving screening protocols, and advancements in medical technology, to ensure effective, patient-centric cervical cancer screening.
The authors stated that p16/Ki-67 dual staining, while sensitive, exhibits lower specificity compared to traditional cytology, which raises the possibility of false-positive results; thus, its clinical application demands a balanced approach, harmonizing the high sensitivity with the need for specificity. This balance is crucial to ensure patient-centered care that is both effective and economical, avoiding over-diagnosis and over-treatment. These investigators stated that the limitations of dual-stained p16/Ki-67 in cervical cancer screening include its potential for false positives in cases of transient HPV infections not progressing to cancer, resulting in unnecessary follow-up procedures. Furthermore, its effectiveness may vary across different age groups, and HPV vaccination statuses, potentially impacting its utility in certain populations. The cost and need for specialized laboratory equipment and expertise could also limit its accessibility, especially in low-resource settings. These factors underscored the importance of considering the context and patient population when integrating dual staining into screening protocols.
An UpToDate review on “Cervical cancer screening tests: Techniques for cervical cytology and human papillomavirus testing” (Feldman and Crum, 2024) states that “Most laboratories offer other tests to assist in reading abnormal cytology slides that have an increased detection of cervical abnormalities. These include commercial tests that detect molecular markers (e.g., dual stain p16/Ki-67) that are highly associated with clinically relevant cervical neoplasia; testing negative for these markers is associated with almost no risk of disease. Such testing is quickly becoming routine for cytopathologists to order as it aids in their diagnosis of equivocal cervical cytology (e.g., atypical squamous cells of undetermined significance [ASCUS], low-grade squamous intraepithelial lesion [LSIL]”.
Furthermore, National Comprehensive Cancer Network’s clinical practice guideline on “Cervical Cancer” (Version 2.2024) does not mention Ki-67, dual staining, or p16/Ki-67 testing. However, it provides the following information:
- Recommend human papillomavirus (HPV) status on all cervical adenocarcinomas. HPV in situ hybridization (ISH) or molecular testing is preferred, but p16 may be acceptable if HPV testing is not available.
Self-Collected / Self-Sampling HPV Tests
Catarino et al (2017) compared HPV test positivity and accuracy between self-collected sample with a dry swab (s-DRY) versus physician-collected cervical sampling using a broom like brush and immediate immersion in PreservCyt (dr-WET). In this cross-sectional study, these researchers recruited 150 women greater than or equal to 18 years old attending the colposcopy clinic in the University Hospital of Geneva. Each participant first self-collected a vaginal sample using a dry swab and then the physician collected a cervical specimen in PreservCyt. HPV analysis was performed with Xpert. Part of the PreservCyt-collected sample was used for high-risk HPV (hrHPV) detection with the Cobas HPV test. HPV test positivity and performance of the 2 collection methods was compared. HPV positivity was 49.1 % for s-DRY, 41.8 % for dr-WET and 46.2 % for Cobas. Good agreement was found between s-DRY and dr-WET samples (kappa ± Standard error (SE) = 0.64 ± 0.09,), particularly for low-grade squamous intraepithelial lesions (LSIL+) (kappa ± SE = 0.80 ± 0.17). Excellent agreement was found between the 2 samples for HPV16 detection in general (kappa ± SE = 0.91 ± 0.09) and among LSIL+ lesions (kappa ± SE = 1.00 ± 0.17). Sensitivities and specificities were, respectively, 84.2 % and 47.1 % (s-DRY), 73.1 % and 58.7 %. (dr-WET) and 77.8 % and 45.7 % (Cobas) for CIN2+ detection. The median delay between sampling and HPV analysis was 7 days for the Xpert HPV assay and 19 days for Cobas. There were 36 (24.0 %) invalid results among s-DRY samples and 4 (2.7 %) among dr-WET (p = 0.001). Invalid results happened due to the long interval between collection and analysis. The authors concluded that self-collected vaginal dry swabs were a valid alternative to collecting cervical samples in PreservCyt solution for HPV testing with the Xpert HPV assay. They stated that HPV self-collection with dry cotton swabs might assist in the implementation of an effective screening strategy in developing countries.
Asciutto et al (2017) compared HPV DNA detection in self-collected vaginal and urine samples with clinician-taken cervical samples in relation to histology. Self-collected vaginal, urine and clinician-taken cervical samples were analyzed from 218 women with the Cobas 4800 HPV test (Roche Molecular Diagnostics). The sensitivity for detection of HPV in the vaginal self-sampling test was 96.4 % and in urine was 83.9 % relative to detection by clinician-taken cervical sample. The vaginal self-sampling and the clinician-taken HPV tests had the same sensitivity of 92.8 % (95 % CI: 86.3 to 96.8 %) and specificity for detection of high-grade squamous intraepithelial lesion (HSIL) and adenocarcinoma in situ (AIS). Detection in urine samples had a sensitivity of 76.3 % (95 % CI: 67.9 to 84.2 %) for HSIL/AIS. The authors concluded that the Cobas 4800 HPV test detected high-grade pre-cancerous cervical lesions in self-collected vaginal samples with the same high sensitivity as in clinician-taken cervical samples.
Chatzistamatiou et al (2017) examined the feasibility of a site-of-care cervico-vaginal self-sampling methodology for HPV-based screening in 346 women residing in under-served rural areas of Northern Greece. These women were provided self-collected cervico-vaginal sample along with a study questionnaire. Following molecular testing, using the Cobas HPV Test, HPV-positive women, were referred to colposcopy and upon abnormal findings, to biopsy and treatment. Participation rate was 100 %. Regular pap-test examination was reported for 17.1 %. Among hrHPV testing, 11.9 % were positive and colposcopy/biopsy revealed 2 CIN3 cases. Non-compliance was the most prevalent reason for no previous attendance. Most women reported non-difficulty and non-discomfort in self-sampling (77.6 % and 82.4 %, respectively). They would choose self-sampling over clinician-sampling (86.2 %), and should self-sampling being available, they would test themselves more regularly (92.3 %). The authors concluded that self-sampling was feasible and well-accepted for HPV-based screening, and could increase population coverage in under-served areas, helping towards successful prevention.
Braz et al (2017) noted that cervical cancer is a major cause of death in adult women. However, many women do not undergo cervical cancer screening for the following reasons: fear, shame, physical limitations, cultural or religious considerations and lack of access to health care services. Self-collected vaginal smears maybe an alternative means of including more women in cervical cancer screening programs. In a systematic review, these investigators evaluated the acceptability of vaginal smear self-collection for cervical cancer screening. They selected articles from PubMed, the Cochrane Library and Embase that were published between January 1995 and April 2016. Studies written in English, French, Italian, Portuguese or Spanish that involved women between 18 and 69 years of age who had engaged in sexual intercourse were included in this review. The review was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. A total of 19 studies were evaluated in this review. Most of the included studies (n = 17) demonstrated that the self-collection method exhibited outstanding acceptability among women with respect to cervical cancer screening, and only 2 studies indicated that self-collection exhibited low acceptability among women in this context. The acceptability of self-collection was determined subjectively (without standardized questionnaires) in 10 studies (53 %) and via structured and validated questionnaires in the remaining studies. The authors concluded that the results of this review suggested that the self-collection method was well-accepted and may therefore encourage greater participation in cervical cancer screening programs. Moreover, they stated that additional studies are needed to verify these findings.
Lim et al (2017) examined the feasibility and acceptability of offering self-sampling for HPV testing to cervical screening non-attenders when they consult primary care for any reason. In a pilot implementation study, 6 general practices in London, UK, offered self-sampling kits during consultation to women aged 25 to 64 years who were at least 6 months overdue for cervical screening (no cytology test recorded in the past 3.5 years if aged 25 to 49, or 5.5 years if aged 50 to 64). Eligible women were identified using an automated real-time search (during consultation) of the general practice electronic medical record system. Women collected samples either in clinic or at home (dry flocked swabs analyzed using Roche Cobas 4800). Of approximately 5,000 eligible women, 3,131 consulted primary care between January and December 2014 (mean recruitment period of 9.5 months). Of these, 21 % (652) were offered kits, 14 % (443) accepted, and 9 % (292) returned a self-sample. The proportion of eligible women offered kits varied markedly among practices (11 to 36 %). Sample return rates increased with kit offered rates ( r = 0.8, p = 0.04). Of 39 HPV-positive women 85 % (33) attended follow-up, including 2 with invasive cancers (stage 2A1 and 1A1). The authors concluded that offering self-sampling to cervical screening non-attenders opportunistically in primary care was feasible. They stated that return rates could be increased if more women were offered kits. Moreover, they stated that a large trial is needed to identify how self-sampling is best integrated into the national screening program, and to identify determinants of uptake.
Modibbo et al (2017) stated that cervical cancer incidence and mortality rates in Sub-Saharan Africa (SSA) remain high due to several factors including low levels of uptake of cervical cancer screening. Self-collection of cervico-vaginal samples for HPV DNA testing may be an effective modality that can increase uptake of cervical cancer screening in SSA and hard to reach populations in developed countries. These researchers examined if self-collection of cervico-vaginal samples for HPV DNA tests would be associated with increased uptake of screening compared with clinic based collection of samples. Furthermore, these investigators compared the quality of samples collected by both approaches for use in HPV genotyping. They conducted a community-based randomized trial in a semi-urban district of Abuja, Nigeria with 400 women, aged 30 to 65 years randomized to either hospital-collection or self-collection of cervico-vaginal samples. These researchers compared cervical cancer screening uptake among the 2 groups and evaluated the concentration of human DNA in the samples by measuring RNase P gene levels using qPCR. High-risk HPV DNA detection and typing was done using the GP5+/6+ Luminex system. Most participants in the self-collection arm (93 %, 185/200) submitted their samples, while only 56 % (113/200) of those invited to the hospital for sample collection attended and were screened during the study period (p < 0.001). Human genomic DNA was detected in all but 5 (1.7 %) participants, all of whom were in the self-collection arm. The prevalence of high-risk HPV in the study population was 10 % with types 35, 52 and 18 being the commonest. The authors concluded that the findings of this study showed that self-sampling significantly increased uptake of HPV DNA based test for cervical cancer screening in this population and the samples collected were adequate for HPV detection and genotyping. They stated that cervical cancer screening programs that incorporate self-sampling and HPV DNA tests were feasible and may significantly improve uptake of cervical cancer screening in SSA; and this justified further studies that integrate this modality into cervical cancer screening programs in low and middle income countries.
The authors stated that a drawback of this study was the use of interviewer administered questionnaires that may have skewed responses to some of the sensitive questions towards what was perceived to be more socially acceptable, however studies have shown that the influence of biased responses were minor and did not affect overall results. The demographic characteristics of the participants in this study also differed from that of the general Nigeria population and this may limit the generalizability of these results. Some members of the community may have opted not to respond to the invitations to participate in the study and the authors could not rule out healthy volunteer bias.
Lofters et al (2017) stated that with appropriate screening (i.e., the Pap test), cervical cancer is highly preventable, and high-income countries, including Canada, have observed significant decreases in cervical cancer mortality. However, certain subgroups, including immigrants from countries with large Muslim populations, experience disparities in cervical cancer screening. Little is known about the acceptability of HPV self-sampling as a screening strategy among Muslim immigrant women in Canada. This study assessed cervical cancer screening practices, knowledge and attitudes, and acceptability of HPV self-sampling among Muslim immigrant women. A convenience sample of 30 women was recruited over a 3-month period (June to August 2015) in the Greater Toronto Area. All women were between 21 and 69 years old, foreign-born, and self-identified as Muslim, and had good knowledge of English. Data were collected through a self-completed questionnaire. More than 50 % of the participants falsely indicated that Pap tests may cause cervical infection, and 46.7 % indicated that the test is an intrusion on privacy. The majority of women reported that they would be willing to try HPV self-sampling, and more than 50 % would prefer this method to provider-administered sampling methods. Barriers to self-sampling included confidence in the ability to perform the test and perceived cost, and facilitators included convenience and privacy being preserved. The authors concluded that although HPV self-sampling has been studied in a variety of other populations, this body of work was the first that these researchers knew of to examine the acceptability of this method among Muslim immigrant women in Canada. This study added important information to the literature related to promoting cancer screening among women under or never screened for cervical cancer. The results demonstrated that HPV self-sampling may provide a favorable alternative model of care to the traditional provider administered Pap testing. It has the potential to increase participation in cervical cancer screening. Potential benefits from HPV self-sampling may include removing several major barriers identified in the literature, such as modesty, access to female physicians, lack of transportation, and inconvenient hours of service. Moreover, they stated that future larger-scale research is needed to allow women of a broad range of ages and ethnicities to trial devices to further explore acceptability and feasibility.
The authors stated that this study had several drawbacks. First, the small sample size (n = 30) was reflective of the qualitative nature of the other component of this body of work. Due to the small sample size and the demographics of participants, results must be interpreted with caution and cannot be generalized to the broader population of Muslim immigrant women in this setting future research will need to be conducted on a larger scale, will need to include a diversity of ages and ethnicities, and will need to allow women to try self-sampling devices to further assess acceptability and feasibility. Second, these findings may have been affected by self-report and social desirability biases, including around reported screening status. Third, these researchers were not able to allow women to try HPV self-sampling to provide more detailed feedback about acceptability, but as noted, planned future research will address this limitation.
In a randomized controlled trial (RCT), Viviano et al (2017) examined if self-sampling can increase screening attendance of women who do not attend regular screening in Switzerland. Participants were proactively recruited in Geneva between September 2011 and November 2015. Women (25 to 69 years) who had not undergone cervical cancer (CC) screening in the last 3 years were considered eligible. Through a 1 : 1 ratio randomization, enrolled participants were invited to either undergo liquid-based cytology, which was performed by a health-care provider (control group, CG) or to take a self-sample for HPV-testing, which was mailed to their home (intervention group, IG). A total of 331 and 336 women were randomized in the CG and in the IG, respectively. Overall, 7.3 % (95 % CI: 4.9 to 10.6) women in the CG and 5.7 % (95 % CI: 3.6 to 8.7) women in the IG did not undergo the initial screening (p = 0.400). There were 1.95 % (95 % CI: 0.8 to 4.3) women in the CG and 5.05 % (95 % CI: 3.1 to 8.1) women in the IG with a positive screen who did not attend triage and colposcopy (p = 0.036). The authors concluded that the participation in CC screening in women offered self-sampling was not higher than among those offered specimen collection by a clinician. Moreover, they stated that compliance with further follow-up for women with a positive HPV test on the self-sample requires further attention.
The authors stated that this study had several drawbacks. First, these researchers were able to recruit fewer participants than expected by the sample size estimation. The assumptions used to estimate the sample size were different from the actual recruitment process of the trial, thus limiting the power to obtain statistically significant difference between the 2 options for initial screening. Second, this study was conducted in an urban setting, which limits the generalization of these findings to the population living in Switzerland. Another reason for which the study group was not entirely representative of the population living in Geneva and its surroundings was the proportion of women with previous CC screening, which was rather high as compared with the lower rates in Geneva and its surroundings. Third, an important pre-selection bias was likely to have occurred since these investigators selected women who had actively responded to the campaign’s advertisements, participants were possibly more willing to accept any CC screening approach than the general population.
Kobetz et al (2017) noted that under-served ethnic minority women experience significant disparities in cervical cancer incidence and mortality, mainly due to lack of cervical cancer screening. Barriers to Pap smear screening include lack of knowledge, lack of health insurance and access, and cultural beliefs regarding disease prevention. In the previous SUCCESS trial, these investigators demonstrated that HPV self-sampling delivered by a community health worker (CHW) is efficacious in circumventing these barriers. This approach increased screening uptake relative to navigation to Pap smear screening. SUCCESS trial participants, as well as community partners, provided feedback that women may prefer the HPV self-sampler to be delivered through the mail, such that they would not need to schedule an appointment with the CHW. Thus, the current trial aims to elucidate the efficacy of the HPV self-sampling method when delivered via mail. These researchers are conducting a RCT among 600 Haitian, Hispanic, and African-American women from the South Florida communities of Little Haiti, Hialeah, and South Dade. Women between the ages of 30 and 65 years who have not had a Pap smear within the past 3 years are eligible for the study. Women are recruited by CHWs and complete a structured interview to assess multi-level determinants of cervical cancer risk. Women are then randomized to receive HPV self-sampling delivered by either the CHW (group 1) or via mail (group 2). The primary outcome is completion of HPV self-sampling within 6 months post-enrollment. The authors concluded that this trial is among the first to examine the efficacy of the mailed HPV self-sampling approach. If found to be efficacious, this approach may represent a cost-effective strategy for cervical cancer screening within under-served and under-screened minority groups.
de Thurah et al (2018) undertook a systematic literature review to determine the concordance in positive test results (i.e., detection of HPV infections) between Hybrid Capture 2 (HC2) and other assays. These investigators searched PubMed, Embase and Scopus for studies of primary screening with HC2 and one or more assays, with cross-tabulated testing results for the assays. Two authors applied inclusion criteria and 3 authors extracted data from included studies. For each inter-assay comparison, these researchers calculated the concordance by comparing the number of concordant samples with the number of samples that tested positive on at least 1 assay. A total of 16 studies fulfilled inclusion criteria, comparing 9 assays to HC2, and including 392 to 9,451 patients each. The calculated concordance varied between 48 % and 69 % for HC2 and APTIMA, Cobas, Abbott RealTime, Cervista, GP5+/6+, CLART, BD HPV test, Amplicor and Linear Array, i.e., 31 % to 52 % of all positive tests on any pair of compared assays were discordant. Although modest variation in the degree of concordance with HC2 was suggested for particular assays, the numbers of studies per assay were generally low. No pronounced systematic patterns were observed by study (e.g., liquid medium) or population characteristics. The authors concluded that the 10 commercially available assays did not detect the same HPV infections. Moreover, they stated that even in the most favorable case, the 2 assays provided discordant test results in 31 % of all detected infections.
Phoolcharoen et al (2018) studied the concordance between vaginal self- and endocervical physician-collected hrHPV testing in Thai women who attended a colposcopy clinic. Vaginal samples were obtained by self-sampling with a dry brush before endocervical samples were obtained by physicians. Both specimens were analyzed for hrHPV by Cobas4800 HPV test. Of the 247 pairs of samples, overall hrHPV prevalence from self- and physician-collected samples was 41.3 % and 36.0 %, respectively. The overall agreement between the methods was 74.5 % with κ 0.46 (p < 0.001). This study revealed moderate agreement between self- and physician-collected methods for hrHPV testing.
The authors stated that this study had several limitations. First, all the participants in the study did the self-collection first then underwent pelvic examination to obtain physician-collected specimens later. This sampling order may have resulted in the self-collected specimens having more exfoliated cells than the physician-collected specimens had. Second, the participants were women who attended a colposcopy clinic for various reasons such as abnormal cytology or positive HPV testing, so the prevalence of HPV in this group was higher than in the normal population. The prevalence of hrHPV in this study was 41.3 % and 36.0 % from self- and physician-collected specimens, respectively. The prevalence of hrHPV in Thai women in previous studies was 3.3 to 14.0 %. Lastly, due to the level of agreement in this study was slightly lower than in most previous studies, more studies with larger populations are needed to explore the reliability and feasibility of self-sampling of HPV as a method for cervical cancer screening in Thai and other Asian women. The molecular and biomarker analyses may be combined to achieve greater accuracy of the test.
Winer et al (2018) noted that women who delay or do not attend Pap screening are at increased risk for cervical cancer. Trials in countries with organized screening programs have demonstrated that mailing hrHPV self-sampling kits to under-screened women increases participation, but U.S. data are lacking. HOME is a pragmatic RCT set within a U.S. integrated healthcare delivery system to compare 2 programmatic approaches for increasing cervical cancer screening uptake and effectiveness in under-screened women (greater than or equal to 3.4 years since last Pap) aged 30 to 64years: First – usual care (annual patient reminders and ad-hoc outreach by clinics), and second – usual care plus mailed hrHPV self-screening kits. Over 2.5 years, eligible women were identified through electronic medical record (EMR) data and randomized 1:1 to the intervention or control arm. Women in the intervention arm were mailed kits with pre-paid envelopes to return samples to the central clinical laboratory for hrHPV testing. Results were documented in the EMR to notify women's primary care providers of appropriate follow-up. Primary outcomes are detection and treatment of cervical neoplasia. Secondary outcomes are cervical cancer screening uptake, abnormal screening results, and women's experiences and attitudes towards hrHPV self-sampling and follow-up of hrHPV-positive results (measured through surveys and interviews). The trial was designed to evaluate whether a programmatic strategy incorporating hrHPV self-sampling is effective in promoting adherence to the complete screening process (including follow-up of abnormal screening results and treatment). The objective of this report is to describe the rationale and design of this pragmatic trial.
An UpToDate review on “Screening for cervical cancer” (Feldman et al, 2018) does not mention the sue of “self-collection or self-sampling” HPV testing.
Furthermore, National Comprehensive Cancer Network’s clinical practice guideline on “Cervical cancer” (Version 1.2018) does not mention “self-collection or self-sampling” HPV testing.
Human Papillomavirus (HPV) Genotyping in Cervical Cancer Screening
Bonde and colleagues (2020) stated that 13 HPV genotypes are associated with the highest risk of cervical disease/cancer; however, the risk of disease progression and cancer is genotype-dependent. In a systematic review, these researchers examined evidence for high-grade cervical intraepithelial neoplasia (greater than or equal to CIN 3) risk discrimination using HPV genotyping. They carried out a systematic review of English and non-English articles through Medline, Cochrane, clinicaltrials.gov, and abstracts presented at relevant professional society conferences were searched from 2000 to 2019. Search terms included: cervical cancer screening, HPV genotyping, CIN, HPV persistence, humans, and colposcopy; prospective, controlled trials, observational studies, and retrospective studies of residual specimens; evidence included HPV genotyping (beyond genotypes 16/18/45) results. Data were obtained independently by authors using predefined fields. Risk of bias was evaluated with a modified Newcastle-Ottawa Scale. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology facilitated overall quality of evidence evaluation for risk estimation. The study protocol was registered with the PROSPERO International Prospective Register of Systematic Reviews (CRD42018091093). The primary outcome was CIN 3 or worse risk both at baseline and at different follow-up periods. Of 236 identified sources, 60 full texts were retrieved and 16 articles/sources were included. Risk of bias was deemed low; the overall quality of evidence for CIN 3 or worse risk with negative for intraepithelial lesions or malignancies or low-grade squamous intraepithelial cytology was assessed as moderate; that with atypical squamous cells-undetermined significance and "all cytology" was assessed as high. Clinical and methodological heterogeneity precluded meta-analysis. Human papillomavirus genotyping discriminated risk of CIN 3 or worse to a clinically significant degree, regardless of cytology result. The authors concluded that the evidence supported a clinical utility for HPV genotyping in risk discrimination during cervical cancer screening. Moreover, these researchers stated that before large-scale implementation, this use of genotype information would need formal evaluation and recommendations by groups issuing clinical testing guidelines. Recently, the United Kingdom’s National Institute for Health Research Health Technology Assessment concluded that HPV assays identifying not only HPV 16 and 18, but in addition HPV 31, 33, 45, 52, and 58, could be useful in triage as well as in primary HPV testing. Finally, the Danish National Health Authority Steering Committee on cervical screening has included use of genotyping and cytology as a combined triage of primary screening HPV positive women for a defined implementation period starting 2020, becoming the first country to use not just HPV screening, but HPV genotype information in an advanced screening algorithm poised at reducing over-treatment while maintaining the sensitivity of HPV-based screening.
The authors stated that a limitation of this analysis was that across the published literature, researchers have developed different methods for assigning genotype in the case of mixed infections. For useful genotype risk assessment, genotypes must be included in order from most discriminatory to least. To determine this order, variations of 3 different approaches may be used. In this analysis, the hierarchical method was preferred, where possible. The models for iterative attribution of risk rank were as follows: multi-variate analysis, descending positive predictive values, and higher risk by single-genotype analysis. An alternative technique was to exclude all multiple infections and rank order risk for single genotype results only. The simple proportional method of according equal risk to each genotype found in mixed infection results in totals exceeding 100 %, and over-estimation of risk for genotypes of lesser rank order. An underlying assumption for all the hierarchical models was that mixed infections do not involve synergism that led to risk greater than that associated with either individual genotype. The period over which risk was estimated differed for many studies; 5 reported baseline risks, 6 reported risks between of 16 months and 4 years, and the remaining studies reported cumulative risks for a range of 4 to 14 years. Rare cases of pre-malignant and invasive cervical lesions are related to non-high-risk HPV genotypes; these cases were not a focus of this systematic review but have been a confounding factor in some to the studies included in this synthesis. Another drawback of this analysis was that cervical cancer screening in the studies that constitute the data sources for this review were performed on different patient populations, which included differences in age, race, screening history, HPV genotype prevalence, disease prevalence, time to follow-up (from 16 months to 14 years), and clinical management at baseline screening and follow-up testing. Study populations also varied by size and cytology result, both of which impacted the interpretation of results when considering the most appropriate risk thresholds for clinical management. In addition, HPV genotyping information was obtained from different methodology including PCR and sequencing – allowing for differences in sensitivity/specificity due to the intrinsic differences in the clinical cutoff values for respective assays.
The U.S. Preventive Services Task Force (USPSTF)’s Recommendation Statement on “Screening for Cervical Cancer” (No authors listed, 2019) did not mention HPV genotyping.
National Comprehensive Cancer Network’s clinical practice guideline on “Cervical cancer” (Version 1.2020) does not mention HPV genotyping as a management tool. Moreover, the NCCN Guidelines Panel for Cervical Cancer Screening endorses the following guidelines: For the prevention and early detection of cervical cancer: American Cancer Society, American Society for Colposcopy and Cervical Pathology, and American Society for Clinical Pathology screening guidelines for the prevention and early detection of cervical cancer (Saslow et al, 2012), which stated that “Other strategies have aimed to improve specificity and reduce harm by interposing secondary testing for management decisions between a positive HPV test and colposcopy. Potential secondary biomarkers included HPV genotyping (for HPV16 or HPV16/18), HPV mRNA testing, and/or the detection of other non-HPV biomarkers (e.g., p16INK4A). Although promising, there are limited data regarding the test performance of these markers. Specifically, the cross-sectional and archival nature of most available molecular marker studies as well as the heterogeneity of clinical endpoints examined (CIN2+ vs CIN3+) limits the current usefulness of these data. Finally, there are no direct comparisons of these various triage strategies and the specificity of such an approach, and the consequential potential harms (or benefits) have not yet been well defined”.
DYSIS Smart Colposcopy
DYSIS Smart Colposcopy entails computer-aided mapping of cervix uteri during colposcopy, including optical dynamic spectral imaging and algorithmic quantification of the aceto-whitening effect. The DYSIS Colposcope measures the reaction of the cervical epithelium using a proprietary technology called Dynamic Spectral Imaging. The cervical mapping technology helps draw attention to any additional areas of the cervix that may need further examination.
Rahatgaonkar and colleagues (2020) noted that cervical cancer is a major contributor to mortality and morbidity in women. Naked eye visual screening (NE test) and Pap test are commonly used for cervical cancer screening. Both tests have inherent limitations like low sensitivity (Pap test) and subjectivity in interpretation, lack of permanent record and over-estimation (NE test). In a prospective, observational study, these researchers compared Smart Scope visual screening test (SS test) with NE and Pap tests. Smart Scope is a small, hand-held device that captures cervical images attached to a tablet to store data. This trial was carried out at a tertiary care hospital in India, over 16 months. A total of 509 women aged 25 to 65 years were included in the study as per the inclusion criteria. All subjects underwent Pap test, NE test and SS test. Screen positives on any 1 test were advised colposcopy and biopsy. Of the 154 screen-positive women, 49 visited for follow-up colposcopy-guided biopsy; 9 incidental biopsies of screen-negative women were included in the data. Therefore, statistical analysis was conducted based on 58 available histopathology results. Of the 58 biopsies, 8 were normal, 30 were benign lesions, 18 were pre-cancerous, and 2 were cancerous lesions. SS test was found to have a sensitivity and NPV of 100 % each, PPV of 45.4 % and a specificity of 36.8 %. Sensitivity and specificity of NE test was 90 % and 39.5 % respectively, PPV was 43.9 % and NPV was 88.2 %. Pap smear had a sensitivity of 25 % and specificity of 84.2 %, PPV of 45.5 % and NPV of 68.08 %. The authors concluded that SS test has great potential to be a primary screening test in low-resource settings due to its better sensitivity and NPV as compared to NE and Pap tests. Moreover, these researchers also stated that a machine learning model is being developed for auto-assessment of lesions; and further efforts are in place to improve the image quality and magnification of the camera.
The authors stated that this study had 2 main drawbacks. First, SS test showed a very low specificity and PPV. Second, this study was carried out in the out-patient department of a tertiary care hospital and all the screening and interpretations were performed by a single expert. These researchers plan to involve the expertise of more than 1 observer in future trials; and they also plan to carry out a similar study in rural settings where the device will be used by a primary health care worker.
UpToDate reviews on “Screening for cervical cancer in resource-rich settings” (Feldman et al, 2021), “” (, 2020) and “Cervical cancer screening tests: Techniques for cervical cytology and human papillomavirus testing” (Feldman and Crum, 2021) do not mention computer-aid mapping/optical dynamic spectral imaging as a screening tool.
Furthermore, National Comprehensive Cancer Network’s clinical practice guideline on “Cervical cancer” (Version 1.2021) does not mention computer-aid mapping/optical dynamic spectral imaging as a management tool.
High-Risk Human Papillomavirus (hrHPV) E6/E7 mRNA Testing
Rijkaart et al (2012) examined if high-risk HPV (hrHPV) mRNA detection by PreTect HPV-Proofer could be used to stratify hrHPV DNA-positive women of different cytology classes for risk of high-grade CIN or worse (cervical pre-cancer or cancer, i.e., CIN grade 2 or higher). A total of 375 women participating in population-based screening, with a GP5+/6+-PCR hrHPV DNA-positive cervical scrape with normal cytology (n = 202), borderline or mild dyskaryosis (BMD) (n = 88), or moderate dyskaryosis or worse (> BMD) (n = 85), were enrolled. Cervical scrapes were additionally subjected to HPV16/18/31/33/45 E6/E7 mRNA analysis by PreTect HPV-Proofer (mRNA test). Referral and follow-up policies were based on cytology, hrHPV DNA, and mRNA testing. The primary study endpoint was the number of CIN grade 2 or higher detected within 3 years of follow-up. The mRNA positivity increased with the severity of cytological abnormality, ranging from 32 % (64/202) in hrHPV DNA-positive women with normal cytology to 47 % (41/88) in BMD and 68 % (58/85) in >BMD groups (p < 0.01). Women with CIN grade 2 or higher were more likely to test positive by mRNA test (63 %) than women without evidence of CIN grade 2 or higher (32 %; p < 0.01). A positive mRNA test result conferred an increased CIN grade 2 or higher risk in hrHPV DNA-positive women with normal cytology, i.e., 0.55 (95 % CI: 0.34 to 0.76) in mRNA-positive versus 0.20 (95 % CI: 0.07 to 0.33) in mRNA-negative women. In hrHPV DNA-positive women with BMD or >BMD, the result of the mRNA test did not influence the CIN grade 2 or higher risk. The authors concluded that mRNA testing by PreTect HPV-Proofer might be of value to select hrHPV DNA-positive women with normal cytology in need of immediate referral for colposcopy. This approach would save these women from extra follow-up visits. However, HPV DNA-positive women who test negative with PreTect HPV-Proofer should still undergo follow-up examinations, since their risk of CIN grade 3 is too high to leave these women without follow-up examinations or treatment.
The authors stated that this study had several drawbacks. First, subjects were recruited at general practitioner practices in the Netherlands. Although the target group was women invited for population-based screening, in practice a number of women outside the age range for population-based cervical screening in the Netherlands (i.e., less than 30 or greater than 60 years) who underwent opportunistic screening in these practices had also been enrolled. However, data were similar when these researchers restricted their analyses to women within the screening age. Second, during follow-up, exceptions to the protocol were also encountered, resulting in a loss of samples for clinical evaluation. Third, as cytology was the selection criterion for inclusion in the study, baseline mRNA data could not be compared to baseline cytological results. The statistical outcomes will therefore be biased toward cytology, which was further emphasized by the fact that cytology was the main decisive factor for colposcopy and biopsy referral. Fourth, it should be realized that the number of women with histologically confirmed absence of CIN grade 2 or higher was relatively low; thus, these investigators extended this category by including women who had a double-negative cytology and hrHPV DNA test result at the last follow-up visit. These women had a negligible risk of CIN grade 2 or higher. Hence, it was unlikely that extension of the absence of CIN grade 2 or higher group with “double-negative” women would have a major influence on the risk evaluation. Fifth, the collection medium used in this study had not been validated for mRNA analysis by PreTect HPV-Proofer, and only 1/10 of the specimens were available for mRNA analysis. As a consequence, the input amount was less than what was recommended for HPV E6/E7 mRNA analysis by PreTect HPV-Proofer. Indeed, the observed human U1 small nuclear ribonucleoprotein specific protein A (U1A) failure rate in the current study (12.8 %) was higher than what is usually observed (i.e., 3 % to 5 %); thus,, it could not be ruled out that some of the HPV mRNA results in this study were false negatives.
Li et al (2021) stated that hrHPV mRNA testing, the FDA-approved testing platform since 2013, has been increasing as a cervical screening alternative to hrHPV DNA testing methods. These investigators reported the largest routine clinical follow-up study reported to-date of hrHPV mRNA co-testing and histopathologic follow-up results for women with HSIL cytology results. HSIL Pap test results for women co-tested with Aptima hrHPV mRNA testing between June 2015 and November 2020 were analyzed along with recorded histopathologic follow-up results within 6 months of screening. Aptima hrHPV mRNA-positive results were reported for 95.2 % of the co-tested HSIL cytology cases (905 of 951). Histopathologic CIN2+ was diagnosed on follow-up in 538 of 701 hrHPV mRNA-positive cases (76.8 %) and in 15 of 36 hrHPV mRNA-negative cases (41.7 %). Additional reviews of the hrHPV mRNA-negative HSIL cases showed variable interpretations, and confirmatory blinded-review interpretations of HSIL or atypical squamous cells, could not exclude HSIL were more likely in cases with histopathologic CIN2+ (77.5 % [93 of 120]) than those with CIN grade 1 or negative findings (63.1 % [101 of 160]; p < 0.01). The authors concluded that this large routine-clinical-practice study confirmed the previously reported high sensitivity of hrHPV mRNA testing for the detection of high-grade cervical dysplasia and cervical cancers. The blinded-review findings indicated that additional cytology review may be helpful for confirming an interpretation of HSIL in daily practice, especially for hrHPV-negative HSIL cases. Moreover, these researchers stated that additional longitudinal, long-term follow-up studies using hrHPV mRNA testing are needed to further confirm the promising performance characteristics of this newer method for HPV testing.
Zhang et al (2022) noted that cervical cancer screening is very important in the prevention and treatment of cervical cancer. These researchers examined the performance of the HPV E6/E7 mRNA (Aptima HPV (AHPV)) assay in primary screening and different triage strategies for women undergoing routine cervical screening. A total of 10,002 women aged 35 to 65 years of age were recruited in Liaoning Province and Qingdao City, China. Specimens were tested by LBC and the AHPV assay, and women who tested positive on any test were referred for colposcopy. Genotyping was carried out on all high-risk HPV (HR-HPV)-positive samples. Test characteristics were calculated based on histological review. These researchers identified 109 women with HSIL or worse (HSIL+), including 6 with cervical cancer. The sensitivity of AHPV was clearly higher than that of LBC (92.7 [95 % CI: 87.2 to 97.2] versus 67.9 [95 % CI: 59.6 to 76.1], p < 0.001). The specificity of AHPV was 93.0 (95 % CI: 92.5 to 93.5), which was lower than that of LBC (95.2 [95 % CI: 94.8 to 95.6], p < 0.001). There was no statistical difference between the PPV of AHPV and LBC (13.5 [95 % CI: 11.2 to 16.2] versus 14.3 [95 % CI: 11.4 to 17.6], p = 0.695). The difference of AUC values between the AHPV test (0.928 [95 % CI: 0.904 to 0.953]) and LBC test (0.815 [95 % CI: 0.771 to 0.860]) in detecting HSIL+ was statistically significant (p < 0.001). Finally, among the 3 triage strategies, both the sensitivity (73.4 [95 % CI: 65.1 to 81.7]) and AUC (0.851 [95 % CI: 0.809 to 0.892]) of AHPV genotyping with reflex LBC triage were the greatest. The authors concluded that the AHPV assay is both specific and sensitive for detecting HSIL+ and may be suitable for use in primary cervical cancer screening in China. AHPV genotyping with reflex LBC triage may be a feasible triage strategy. Moreover, these researchers stated that further longitudinal studies and extending genotyping studies are needed for triage strategies in primary HPV screening.
The authors stated that this study had several drawbacks that need to be taken into consideration. First, 37 % of women who needed to refer for colposcopy were not recalled. In future research, these investigators should find ways to improve the colposcopy referral compliance of HPV-positive but cytology-negative women. Second, longitudinal follow-up should be performed in women with both negative LBC and AHPV results. Third, the performance of primary HPV screening with different triage strategies differed among age groups; therefore, evaluation of the age-specific effectiveness of primary AHPV screening and possible triage strategies is needed.
Furthermore, an UpToDate review on “Screening for cervical cancer in resource-rich settings” (Feldman et al, 2022) states that “RNA-based methods are not approved for primary HPV testing. However, they may be as effective as DNA-based methods in detecting cervical disease. In a meta-analysis evaluating the accuracy of different screening methods for detecting CIN 2+ in clinician-obtained samples, testing with RNA compared with DNA-based assays had similar sensitivity and specificity, though internal controls for specimen adequacy were not available for most assays. Sensitivity was lower for self-collected samples (0.84, 95 % CI 0.74-0.96). Further studies evaluating RNA-based methods for primary HPV testing are needed”.
Artificial Intelligence-Based Cervical Cancer Screening
Vinals et al (2023) stated that visual inspection with acetic acid (VIA) is one of the methods recommended by the World Health Organization (WHO) for cervical cancer screening. VIA is simple and low-cost; it, however, presents high subjectivity. These investigators carried out a systematic literature search in PubMed, Google Scholar and Scopus to identify automated algorithms for classifying images taken during VIA as negative (healthy/benign) or pre-cancerous/cancerous. Of the 2,608 studies identified, 11 met the inclusion criteria. The algorithm with the highest accuracy in each study was selected, and some of its key features were analyzed. Data analysis and comparison between the algorithms were performed, in terms of sensitivity and specificity, ranging from 0.22 to 0.93 and 0.67 to 0.95, respectively. The quality and risk of each study were assessed following the QUADAS-2 guidelines. Artificial intelligence (AI)-based cervical cancer screening algorithms have the potential to become a key tool for supporting cervical cancer screening, especially in settings where there is a lack of healthcare infra-structure and trained personnel. The presented studies, however, evaluated their algorithms using small datasets of highly selected images, not reflecting whole screened populations. Furthermore, most of the studies did not report CIs, hindering objective comparison and analysis. These researchers stated that in the future, AI algorithms will probably be an essential tool in cervical cancer screening; however, algorithms must first be generalizable, pre-processing steps optimized, and above all, tested in real-life conditions. The authors stated that algorithms should be trained on larger samples with reliable histological ground truths and various populations with different acquisition procedures, including devices and settings. Proper statistical analysis of their results, demonstrating their generalizability to other populations and settings, is needed to examine their potential to become the future of cervical cancer screening.
DNA Methylation in HPV-Based Cervical Cancer Screening
Salta et al (2023) noted that screening plays a key role in secondary prevention of cervical cancer. High-risk HPV (hrHPV) testing, a highly sensitive test but with limited specificity, has become the gold standard frontline for screening programs; therefore, the importance of effective triage strategies, including DNA methylation markers, has been emphasized. Despite the potential reported in individual studies, methylation markers still require validation before being recommended for clinical practice. In a systematic review and meta-analysis, these investigators examined the performance of DNA methylation-based biomarkers for detecting HSIL in hrHPV-positive women. PubMed, Scopus, and Cochrane databases were searched for studies that evaluated methylation in hrHPV-positive women in cervical scrapes. Histologically confirmed HSIL was used as endpoint, and QUADAS-2 tool enabled assessment of study quality. A bi-variate random-effect model was used to pool the estimated sensitivity and specificity as well as PPV and NPV. A total of 23 studies were included in this meta-analysis, from which cohort and referral population-based studies corresponded to nearly 65 %. Most of the women analyzed were Dutch, and CADM1, FAM19A4, MAL, and miR124-2 were the most studied genes. Pooled sensitivity and specificity were 0.68 (95 % CI: 0.63 to 0.72) and 0.75 (95 % CI: 0.71 to 0.80) for CIN2+ detection, respectively. For CIN3+ detection, pooled sensitivity and specificity were 0.78 (95 % CI: 0.74 to 0.82) and 0.74 (95 % CI: 0.69 to 0.78), respectively. For pooled prevalence, PPV for CIN2+ and CIN3+ detection were 0.514 and 0.392, respectively. Furthermore, NPV for CIN2+ and CIN3+ detection were 0.857 and 0.938, respectively. The authors concluded that this meta-analysis confirmed the great potential of DNA methylation-based biomarkers as triage tool for hrHPV-positive women in cervical cancer screening. Moreover, these researchers stated that standardization and improved validation are needed. They noted that these markers might represent an alternative to cytology and genotyping for colposcopy referral of hrHPV-positive women, allowing for more cost-effective screening programs.
The authors stated that one of the main drawbacks of this meta-analysis was the fact that distinct markers alone or combined in several panel have been reported along with different methodologies (including genes studied and methodological approach), with only a very small number of studies having used exactly the same protocols. Furthermore, in some studies a histological biopsy was not carried out when the co-test was negative, which might be a source of bias, although the reported risk of misclassification was rather low. In addition, some studies considered the women lost to follow-up as negative for CIN2+ lesion, which might be associated with lesion misclassification; thus, might have impacted in the estimated sensitivity and specificity.
Proofer ‘7 HPV mRNA E6 and E7 Biomarker Test
Alaghehbandan et al (2013) noted that the clinical usefulness of the ProEx C (Becton Dickinson) and PreTect HPV-Proofer E6/E7 mRNA tests (Proofer; Norchip) for the triage of atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesion (LSIL) cytology was determined in comparison with the Hybrid Capture 2 HPV DNA test (HC2; Qiagen). The study population consisted of women with a history of abnormal cytology referred to colposcopy. Histology-confirmed CIN 2+ served as the disease endpoint. The study was based on 1,360 women (mean age of 30.7 years), of whom 380 had CIN 2+. Among 315 with ASCUS (CIN 2+, n = 67), the sensitivities of ProEx C, Proofer, and HC2 to detect CIN 2+ were, 71.6 %, 71.6 %, and 95.5 %, respectively, with a corresponding specificity of 74.6 %, 74.2 %, and 35.1 %. Among 363 with LSIL (CIN 2+, n = 108), the sensitivities of ProEx C, Proofer, and HC2 were, 67.6 %, 74.1 %, and 96.3 %, respectively, with a corresponding specificity of 60 %, 68.2 %, and 18.4 %. Among 225 HC2-positive ASCUS (CIN 2+, n = 64), 105 tested positive by ProEx C, reducing colposcopy referral by 53.3 % and detecting 71.9 % of CIN 2+; Proofer was positive in 112/225, reducing colposcopy referral by 50.2 % and detecting 75.0 % of CIN 2+. Among 312 HC2-positive LSIL (CIN 2+, n = 104), 160 tested positive by ProEx C, reducing colposcopy referral by 48.7 % and detecting 66.3 % of CIN 2+; Proofer was positive in 159/312, reducing colposcopy referral by 49.0 % and detecting 75.0 % of CIN 2+. The authors concluded that the overall performance of ProEx C and Proofer were found to be similar but more specific than HC2 for detecting CIN 2+; thus either of these tests could serve as a better tool for risk stratification, and both have the potential to significantly reduce colposcopy referral of ASCUS and LSIL cytology compared to HC2, and as well to reduce colposcopy referral of HC2-positive ASCUS and LSIL cytology. However, the higher specificity of ProEx C and Proofer and the attendant greater reduction in referral rate was achieved at the cost of lowered sensitivity. While either of the tests will be useful in identifying the majority of women requiring referral for immediate colposcopy, both tests will miss a proportion of CIN 2+. The latter is unacceptable under the prevailing clinical practice guidelines and standard of care in the United States. In view of this, based on these results, the authors could not recommend either ProEx C or Proofer for the triage of ASCUS or LSIL in the U.S. while search for additional useful biomarkers singly or in combination continues.
Derbie et al (2020) stated that genital infection with certain types of HPV is a major cause of cervical cancer world-wide. For early detection of pre-malignant dysplasia, evidences are coming out on the usefulness of HPV E6/E7 mRNA test as a potential tool compared with cytology and HPV DNA testing. Considering shortage of compiled data on this field, the objective of this systematic review was to describe the latest diagnostic performance of HPV E6/E7 mRNA testing in detecting high grade cervical lesions (CIN2+). Studies published in English were systematically searched using key words from PubMed/Medline and SCOPUS. Furthermore, Google Scholar and the Google database were searched manually for grey literature. Two reviewers independently assessed study eligibility, risk of bias and extracted the data. They carried out a descriptive presentation of the performance of E6/E7 mRNA test (in terms of sensitivity, specificity, NPV and PPV) for the detection of CIN2 + . Out of 231 applicable citations, these investigators have included 29 studies that included a total of 23,576 subjects (age range of 15 to 84 years) who had different cervical pathologies. Among the subjects who had cervical histology, the proportion of CIN2+ was between 10.6 % and 90.6 %. Using histology as a gold standard, 11 studies evaluated the PreTect HPV Proofer, 7 studies evaluated the APTIMA HPV assay (Gen-Probe), and 6 studies evaluated the Quantivirus HPV assay. The diagnostic performance of these 3 most common mRNA testing tools to detect CIN2+ was: for PreTect Proofer; median sensitivity 83 %, specificity 73 %, PPV 70 % and NPV 88.9 %; for APTIMA assay; median sensitivity 91.4 %, specificity 46.2 %, PPV 34.3 % and NPV 96.3 %; and for Quantivirus: median sensitivity 86.1 %, specificity 54.6 %, PPV 54.3 % and NPV was at 89.3 %. In addition, the AU-ROC curve varied between 63.8 % and 90.9 %. The authors concluded that the reported diagnostic accuracy implied that HPV mRNA-based tests exhibited diagnostic relevance to detect CIN2+ and could potentially be considered in areas where there is no histology facility. Moreover, these investigators stated future research in the field should emphasis on the clinical translation (utility) of HPV E6/E7 mRNA tests using large consecutive cohorts of women, including participants from developing nations, representing a well-defined population for a specific type of cervical pathology.
The authors stated that the main drawback of this review was the lack of studies that employed similar and well-defined population with same cervical pathology characteristics; therefore, the review suffered from heterogeneity of the studies and was not possible to pool the performance of the mRNA tests. Furthermore, the decisive objective of cervical cancer screening is to detect cervical lesions that will develop into cancer. However, the use of histologically confirmed CIN2+ endpoint when evaluating mRNA accuracy represents a challenge because of the regression (false positive) or progression (false negative) of many confirmed lesions. Confining the inclusion criteria to include only studies published in English languages may introduce missing of relevant studies and reduced the precision of these findings.
Xu et al (2024) noted that histology is considered the gold standard for diagnosing the pathological progress of cervical cancer development, while CIN2+ is the cut-off for intervention in clinical practice. The diagnostic value of HPV E6/E7 mRNA in screening for CIN2+ has not been systematically summarized. In a meta-analysis, these researchers examined the diagnostic value of HPV E6/E7 mRNA in screening for CIN2+, aiming to provide a new marker for earlier clinical diagnosis of cervical cancer. The PubMed, Embase and Cochrane Library databases were searched from inception to May 2023. Studies reporting the true positive, false positive, true negative and false negative values in differentiating between CIN2+ and CIN2- were included, while duplicate publications, studies without full text, incomplete information or inability to conduct data extraction, animal experiments, reviews and systematic reviews were excluded. STATA software was used to analyze the data. A total of 2,224 patients were included of whom there were 1,274 patients with CIN2+ and 950 patients with CIN2-. The pooled sensitivity and specificity of the studies overall were 0.89 (95 % CI: 0.84 to 0.92) and 0.59 (95 % CI: 0.46 to 0.71), respectively; the positive likelihood ratio (LR) and the negative LR of the studies overall were 2.31 (95 % CI: 1.61 to 3.32) and 0.21 (95 % CI: 0.14 to 0.30), respectively. The pooled DOR of the studies overall was 11.53 (95 % CI: 6.85 to 19.36); and the AUC was 0.88. The authors concluded that the analysis indicated that HPV E6/E7 mRNA exhibited high diagnostic effectiveness for CIN2+. These researchers noted that HPV E6/E7 mRNA is highly sensitive in the diagnosis of CIN2+, which aids in lowering the rate of missed diagnoses; however, lower specificity may result in a higher number of misdiagnoses in healthy patients.
The authors stated that this study had several drawbacks. First, most of the included studies were retrospective; therefore, potentially introducing selection bias and limiting the generalizability of the findings to broader populations or screening settings. These researchers stated that further large-scale RCTs are needed to validate the findings. Second, most of the included studies were single-center, retrospective studies. Third, while the present study reported no obvious publication bias based on Deek's funnel plot, publication bias could be challenging to detect, especially when the number of included studies was limited. Fourth, the study primarily focused on diagnostic accuracy measures; however, it did not directly examine clinical outcomes, such as the impact of HPV E6/E7 mRNA testing on patient management or the reduction in cervical cancer incidence or mortality. Fifth, the study did not directly compare HPV E6/E7 mRNA testing with other screening methods, making it challenging to examine if this biomarker offers advantages over existing diagnostic approaches.
UpToDate reviews on “Cervical cancer screening: Risk assessment, evaluation, and management after screening” (Goodman et al, 2024), “Screening for cervical cancer in patients with HIV infection and other immunocompromised states” (Robinson, 2024), and “Cervical cancer screening tests: Techniques for cervical cytology and human papillomavirus testing” (Feldman and Crum, 2024) do not mention mRNA gene expression profiling as a management option.
Furthermore, National Comprehensive Cancer Network’s clinical practice guideline on “Cervical Cancer” (Version 3.2024) does not mention mRNA gene expression profiling as a screening tool.
QuantiVirus HPV E6/E7 mRNA Test for Cervical Cancer
The QuantiVirus HPV E6/E7 mRNA test (DiaCarta, Inc) is a single amplification nucleic acid probe assay for qualitative detection of human papillomavirus (HPV) E6/E7 mRNA directly from Pap smear samples or liquid based cytology specimens without RNA purification or RT-PCR to screen for cervical cancer. The test can detect high-risk HPV subtypes 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68. It can be used to screen patients with atypical squamous cells of undetermined significance (ASC-US) cervical cytology results. The results are reported as negative or positive for high risk for HPV, which could lead to cancer.
The use of the QuantiVirus HPV E6/E7 mRNA test is indicated for:
- Screening patients with ASC-US (atypical squamous cells of undetermined significance) cervical cytology results to determine the need for referral to colposcopy;
- In women 30 years and older, the test can be used with cervical cytology to adjunctively screen to assess the presence or absence of high-risk HPV types. This information, together with the physician’s assessment of cytology history, other risk factors, and professional guidelines, may be used to guide patient management;
- The results from the test must be interpreted within the context of all relevant clinical and laboratory findings.
Warnings:
- The positive predictive values of HPV RNA are not intended for use in guiding therapy;
- The test is not intended for use alone in the diagnosis or confirmation of HPV infection;
- Assay performance characteristics have not been established with individuals who have been vaccinated with HPV vaccines.
Liu and colleagues (2014) state that HPV DNA tests tend to show high sensitivity, but poor specificity in detecting high-grade cervical lesions. In a validation study, the authors aimed to explore the clinical performance of QuantiVirus HPV E6/E7 mRNA in identifying Grade 2 or more cervical intraepithelial neoplasia. Thin-prep® liquid based cytology test (LBC) samples were collected from October 2009 to October 2011 from women who underwent outpatient hospital-based gynecological screening. LBC samples were processed for E6/E7 mRNA detection and HPV DNA detection. Of 335 patients, 135 (40.3%) were HPV E6/E7 mRNA positive for high-risk HPV subtypes. The authors found that the positivity rate of HPV E6/E7 mRNA increased with the severity of cytological and histological evaluation. An optimal cut-off value of 567 copies/ml or more was determined using receiver operating characteristic (ROC) curve, and positive/negative predictive value of cut-off value (≥567 copies/ml) were higher than those of E6/E7 mRNA positivity only, but not significant. The authors concluded that the QuantiVirus HPV E6/E7 mRNA testing may be a valuable tool in triage for identifying Grade 2 or more cervical intraepithelial neoplasia. A high specificity and a low positivity rate of E6/E7mRNA testing as a triage test in HPV DNA-positive women could be translated into a low referral for colposcopy. However, studies composed of large population-based samples of women and with rigorous disease ascertainment are needed to establish the optimal cut-off point based on ROC curve analysis.
Yao et al (2017) noted that cytology triage has been generally recommended for HPV-positive women; however, it is highly dependent on well-trained cytologists. These researchers examined if HPV E6/E7 mRNA detection in cervical exfoliated cells can be a potential triage for HPV-positive women from a clinic-based population. Both the primary HPV testing and Pap test were carried out on all eligible HPV-positive women. HPV E6/E7 mRNA was detected by QuantiVirus HPV E6/E7 mRNA assay in cervical exfoliated cells. All HPV-positive women underwent colposcopy and further biopsy if indicated. The data were evaluated by Pearson’s Chi-squared test and the ROC curve. A total of 404 eligible HPV-positive women were enrolled. Positive rate of E6/E7 mRNA in HSIL cases was higher than that in LSIL or normal cases. There was no statistical difference found between mRNA and cytological testing with sensitivity (89.52 % versus 86.67 %, p = 0.671), specificity (48.96 % versus 48.96 %, p = 1.000), PPV (39.00 % versus 38.24 %, p = 1.000), and NPV (92.76 % versus 90.97 %, p = 0.678) for detecting ≥ HSIL. The authors concluded that HPV E6/E7 mRNA detection in cervical exfoliated cells demonstrated the same performance as Pap triage for HSIL identification for HPV-positive women. These investigators stated that detection of HPV E6/E7 mRNA may be a new optional triage for HPV-positive women, especially in areas that lack well-trained cytologists. However, the conclusion may be somewhat limited due to the small sample size and because this trial was a hospital-based one. The conclusion could not be generalized to the general patient population.
Derbie et al (2020) stated that genital infection with certain types of HPV is a major cause of cervical cancer world-wide. For early detection of pre-malignant dysplasia, evidences are coming out on the usefulness of HPV E6/E7 mRNA test as a potential tool compared with cytology and HPV DNA testing. Considering shortage of compiled data on this field, the objective of this systematic review was to describe the latest diagnostic performance of HPV E6/E7 mRNA testing in detecting high grade cervical lesions (CIN2+). Studies published in English were systematically searched using key words from PubMed/Medline and SCOPUS. Furthermore, Google Scholar and the Google database were searched manually for grey literature. Two reviewers independently assessed study eligibility, risk of bias and extracted the data. They carried out a descriptive presentation of the performance of E6/E7 mRNA test (in terms of sensitivity, specificity, NPV and PPV) for the detection of CIN2 + . Out of 231 applicable citations, these investigators have included 29 studies that included a total of 23,576 subjects (age range of 15 to 84 years) who had different cervical pathologies. Among the subjects who had cervical histology, the proportion of CIN2+ was between 10.6 % and 90.6 %. Using histology as a gold standard, 11 studies evaluated the PreTect HPV Proofer, 7 studies evaluated the APTIMA HPV assay (Gen-Probe), and 6 studies evaluated the Quantivirus HPV assay. The diagnostic performance of these 3 most common mRNA testing tools to detect CIN2+ was: for PreTect Proofer; median sensitivity 83 %, specificity 73 %, PPV 70 % and NPV 88.9 %; for APTIMA assay; median sensitivity 91.4 %, specificity 46.2 %, PPV 34.3 % and NPV 96.3 %; and for Quantivirus: median sensitivity 86.1 %, specificity 54.6 %, PPV 54.3 % and NPV was at 89.3 %. In addition, the AU-ROC curve varied between 63.8 % and 90.9 %. The authors concluded that the reported diagnostic accuracy implied that HPV mRNA-based tests exhibited diagnostic relevance to detect CIN2+ and could potentially be considered in areas where there is no histology facility. Moreover, these investigators stated future research in the field should emphasis on the clinical translation (utility) of HPV E6/E7 mRNA tests using large consecutive cohorts of women, including participants from developing nations, representing a well-defined population for a specific type of cervical pathology.
The authors stated that the main drawback of this review was the lack of studies that employed similar and well-defined population with same cervical pathology characteristics; therefore, the review suffered from heterogeneity of the studies and was not possible to pool the performance of the mRNA tests. Furthermore, the decisive objective of cervical cancer screening is to detect cervical lesions that will develop into cancer. However, the use of histologically confirmed CIN2+ endpoint when evaluating mRNA accuracy represents a challenge because of the regression (false positive) or progression (false negative) of many confirmed lesions. Confining the inclusion criteria to include only studies published in English languages may introduce missing of relevant studies and reduced the precision of these findings.
References
The above policy is based on the following references:
- Aberg JA, Gallant JE, Ghanem KG, et al; Infectious Diseases Society of America. Primary care guidelines for the management of persons infected with HIV: 2013 update by the HIV medicine association of the Infectious Diseases Society of America. Clin Infect Dis. 2014;58(1):e1-e34.
- Alaghehbandan R, Fontaine D, Bentley J, et al. Performance of ProEx C and PreTect HPV-Proofer E6/E7 mRNA tests in comparison with the hybrid capture 2 HPV DNA test for triaging ASCUS and LSIL cytology. Diagn Cytopathol. 2013;41(9):767-775.
- Alvarez RD, Wright TC Jr; Optical Detection Group. Increased detection of high-grade cervical intraepithelial neoplasia utilizing an optical detection system as an adjunct to colposcopy. Gynecol Oncol. 2007;106(1):23-28.
- American College of Obstetricians and Gynecologists (ACOG), Committee on Gynecologic Practice. New Pap test screening techniques. Committee Opinion No. 206. Washington, DC: ACOG; August 1998.
- American College of Obstetricians and Gynecologists (ACOG), Committee on Gynecologic Practice. Cervical cytology screening. ACOG Technology Assessment in Obstetrics and Gynecology. No. 2. Washington, DC: ACOG; December 2002.
- American College of Obstetricians and Gynecologists (ACOG), Committee on Practice Bulletins - Gynecology. Cervical cytology screening. ACOG Practice Bulletin No. 45. Washington, DC: ACOG; August 2003.
- American College of Obstetricians and Gynecologists (ACOG), Committee on Practice Bulletins - Management of abnormal cervical cytology and histology. ACOG Practice Bulletin No. 66. Washington, DC:ACOG; September 2005.
- American College of Obstetricians and Gynecologists (ACOG), Committee on Gynecologic Practice. Cervical cytology screening. ACOG Practice Bulletin. No. 109. Washington, DC: ACOG; December 2009.
- American College of Obstetricians and Gynecologists (ACOG). Cervical cancer in adolescents: Screening, evaluation, and management. ACOG Committee Opinion No. 463. Washington, DC: ACOG; August 2010.
- American College of Obstetricians and Gynecologists (ACOG). Diagnosis and treatment of cervical carcinomas. ACOG Practice Bulletin. Clinical Management Guidelines for Obstetrician-Gynecologists No. 35. Washington, DC: ACOG; May 2002.
- American College of Obstetricians and Gynecologists (ACOG). Guidelines for Women's Health Care. 2nd ed. Washington, DC: ACOG; 2002.
- American College of Obstetricians and Gynecologists (ACOG). Management of abnormal cervical cancer screening test results and cervical cancer precursors. ACOG Practice Bulletin No. 140. Washington, DC: American College of Obstetricians and Gynecologists (ACOG); December 2013.
- American College of Obstetricians and Gynecologists (ACOG). Recommendations on the frequency of Pap tests. ACOG Committee Opinion No. 152. Washington, DC: ACOG; March 1995.
- American College of Obstetricians and Gynecologists (ACOG). Cervical cancer screening and prevention. ACOG Practice Bulletin No. 157. Washington, DC: ACOG; January 2016.
- Apgar BS, Brotzman G. HPV testing in the evaluation of the minimally abnormal Papanicolaou smear. Am Fam Physician. 1999;59(10):2794-2801.
- Arbyn M, Simon M, Peeters E, et al. 2020 list of human papillomavirus assays suitable for primary cervical cancer screening. Clin Microbiol Infect. 2021;27(8):1083-1095.
- ASCCP Practice Guideline. Management guidelines for follow-up of atypical squamous cells of undetermined significance (ASCUS). Colposcopist. 1996;27:1-9.
- Asciutto KC, Henningsson AJ, Borgfeldt H, et al. Vaginal and urine self-sampling compared to cervical sampling for HPV-testing with the Cobas 4800 HPV test. Anticancer Res. 2017;37(8):4183-4187.
- Australian Health Technology Advisory Committee (AHTAC). Review of automated and semi-automated cervical screening devices. Canberra, ACT: AHTAC; April 1998.
- Belinson J, Qiao YL, Pretorius R, et al. Shanxi Province Cervical Cancer Screening Study: A cross-sectional comparative trial of multiple techniques to detect cervical neoplasia. Gynecol Oncol. 2001;83:439-444.
- Berek JS, ed. Novak's Gynecology. 12th ed. Baltimore, MD: Williams & Wilkins; 1996:453-454.
- Biazin H. Concordance of Anyplex™ II HPV HR assays with reference HPV assays in cervical cancer screening: Systematic review. J Virol Methods. 2022;301:114435.
- Bonde JH, Sandri MT, Gary DS, Andrews JC. Clinical utility of human papillomavirus genotyping in cervical cancer screening: A systematic review. J Low Genit Tract Dis. 2020;24(1):1-13.
- Braz NS, Lorenzi NP, Sorpreso IC, et al. The acceptability of vaginal smear self-collection for screening for cervical cancer: A systematic review. Clinics (Sao Paulo). 2017;72(3):183-187.
- Broadstock M. Effectiveness and cost effectiveness of automated and semi-automated cervical screening devices. NZHTA Report. 2000;2(1).
- Brown BH, Milnes P, Abdul S, Tidy JA. Detection of cervical intraepithelial neoplasia using impedance spectroscopy: A prospective study. BJOG. 2005;112(6):802-806.
- California Technology Assessment Forum (CTAF). Human papillomavirus testing for primary cervical cancer screening. Technology Assessment. San Francisco, CA: CTAF; March 5, 2008.
- Caraway NP, Khanna A, Dawlett M, et al. Gain of the 3q26 region in cervicovaginal liquid-based pap preparations is associated with squamous intraepithelial lesions and squamous cell carcinoma. Gynecol Oncol. 2008;110(1):37-42.
- Catarino R, Vassilakos P, Bilancioni A, et al. Accuracy of self-collected vaginal dry swabs using the Xpert human papillomavirus assay. PLoS One. 2017;12(7):e0181905.
- Centers for Disease Control and Prevention (CDC), National Center for Chronic Disease Prevention and Health Promotion. Cervical cancer and Pap test information. The National Breast and Cervical Cancer Early Detection Program. Atlanta, GA: CDC; updated May 31, 2002.
- Centers for Disease Control and Prevention (CDC). HPV and men. CDC Fact Sheet. Atlanta, GA: CDC; reviewed March 2006.
- Centers for Disease Control and Prevention (CDC). Human Papillomavirus: HPV Information for Clinicians. CS110004. Atlanta, GA: CDC; April 2007.
- Centers for Disease Control and Prevention. Sexually transmitted diseases treatment guidelines 2002. MMWR Recomm Rep. 2002;51(RR-6):53-57.
- Chang VT, Cartwright PS, Bean SM, et al, Ramanujam N. Quantitative physiology of the precancerous cervix in vivo through optical spectroscopy. Neoplasia. 2009;11(4):325-332.
- Chatzistamatiou K, Chatzaki Ε, Constantinidis Τ, et al. Self-collected cervicovaginal sampling for site-of-care primary HPV-based cervical cancer screening: A pilot study in a rural underserved Greek population. J Obstet Gynaecol. 2017:1-6.
- Chen CC, Huang LW, Bai CH, Lee CC. Predictive value of p16/Ki-67 immunocytochemistry for triage of women with abnormal Papanicolaou test in cervical cancer screening: A systematic review and meta-analysis. Ann Saudi Med. 2016;36(4):245-251.
- Cheung LC, Egemen D, Chen X, et al. 2019 ASCCP risk-based management consensus guidelines: Methods for risk estimation, recommended management, and validation. J Low Genit Tract Dis. 2020;24(2):90-101.
- Clarke MA, Wentzensen N, Perkins RB, et al; Enduring Consensus Cervical Cancer Screening and Management Guidelines Committee. Recommendations for use of p16/Ki67 dual stain for management of individuals testing positive for human papillomavirus. J Low Genit Tract Dis. 2024;28(2):124-130.
- Committee on Quality Assurance Training and Education (CQUATE) of the European Federation of Cytology Societies. European Guidelines for Quality Assurance in Cervical Cancer Screening. Brussels, Belgium: CQUATE; 1997.
- Cox JT, Massad LS, Lonky N, et al. Management guidelines for the follow-up of cytology read as low grade squamous intraepithelial lesion. J Lower Genital Tract Dis. 2000;4(2):83-92.
- Cox JT. Evaluating the role of HPV testing of women with equivocal Papanicolaou test findings [editorial]. JAMA. 1999;281(17):1605-1610.
- Craine BL, Craine ER, O'Toole CJ, Ji Q. Digital imaging colposcopy: Corrected area measurements using shape-from-shading. IEEE Trans Med Imaging. 1998;17(6):1003-1010.
- Danish Centre for Evaluation and Health Technology Assessment (DACEHTA). The use of liquid based cytology (LBC) and conventional Pap smear (CPS) for cervical screening in Denmark. A health technology assessment - summary. Copenhagen, Denmark: DACEHTA; 2005.
- Darragh TM, Colgan TJ, Cox JT, et al.; Members of LAST Project Work Groups. The Lower Anogenital Squamous Terminology Standardization Project for HPV-Associated Lesions: Background and consensus recommendations from the College of American Pathologists and the American Society for Colposcopy and Cervical Pathology. Arch Pathol Lab Med. 2012;136(10):1266-1297.
- Davies P, Arbyn M, Dillner J, et al. A report on the current status of European research on the use of human papillomavirus testing for primary cervical cancer screening. Int J Cancer. 2006;118(4):791-796.
- Davis AJ. Clinical usefulness of HPV testing and genotyping. JournalWatch Women's Health, April 1, 2009.
- de Thurah L, Bonde J, Lam JUH, Rebolj M. Concordant testing results between various human papillomavirus assays in primary cervical cancer screening: Systematic review. Clin Microbiol Infect. 2018;24(1):29-36.
- Denny L. Screening for cervical cancer in resource-limited settings. UpToDate [online serial]. Waltham, MA: UpToDate; reviewed April 2021.
- Derbie A, Mekonnen D, Woldeamanuel Y, et al. HPV E6/E7 mRNA test for the detection of high grade cervical intraepithelial neoplasia (CIN2+): A systematic review. Infect Agent Cancer. 2020;15:9.
- DeVita VT Jr, Hellman S, Rosenberg SA, eds. Cancer Principles & Practice of Oncology. 5th ed. Philadelphia, PA: Lippincott-Raven; 1997:1438.
- DiaCarta, Inc. Product instruction for use: QuantiVirus HPV E6/E7 mRNA test for cervical cancer. Pleasanton, CA: DiaCarta; 2012. Available at: https://filgen.jp. Accessed October 18, 2024.
- Earley A, Lamont JL, Dahabreh IJ, et al. Fluorescence in situ hybridization testing for the diagnosis of high-grade cervical abnormalities: A systematic review. J Low Genit Tract Dis. 2014;18(3):218-227.
- Eftekhar Z, Izadi-Mood N, Yarandi F, et al. Can we substitute brush cytology for biopsy in the evaluation of cervical lesions under the guidance of colposcopy? Int J Gynecol Cancer. 2005;15(3):489-492.
- Einstein MH. Human papillomavirus testing of the cervix: Management of abnormal results. UpToDate [online serial]. Waltham, MA: UpToDate; reviewed August 2020.
- El-Tawil SG, Adnan R, Muhamed ZN, Othman NH. Comparative study between Pap smear cytology and FTIR spectroscopy: A new tool for screening for cervical cancer. Pathology. 2008;40(6):600-603.
- Etherington IJ, Dunn J, Shafi MI, et al. Video colpography: A new technique for secondary cervical screening. Br J Obstet Gynaecol. 1997;104(2):150-153.
- Feldman S, Crum CP. Cervical cancer screening tests: Techniques for cervical cytology and human papillomavirus testing. UpToDate [online serial]. Waltham, MA: UpToDate; reviewed February 2021; March 2024; June 2024.
- Feldman S, Goodman A, Peipert JF. Screening for cervical cancer. UpToDate [online serial]. Waltham, MA: UpToDate; reviewed February 2017; February 2018; April 2021.
- Feldman S, Goodman A, Peipert JF. Screening for cervical cancer in resource-rich settings. UpToDate [online serial]. Waltham, MA: UpToDate; reviewed December 2022.
- Feltmate CM, Feldman S. Colposcopy. UpToDate [online serial]. Waltham, MA: UpToDate; 2008.
- Ferris DG, Litaker MS; ASCUS/LSIL Triage Study (ALTS) Group. Colposcopy quality control by remote review of digitized colposcopic images. Am J Obstet Gynecol. 2004;191(6):1934-1941.
- Frumovitz M. Invasive cervical cancer: Epidemiology, risk factors, clinical manifestations, and diagnosis. UpToDate [online serial]. Waltham, MA: UpToDate; reviewed March 2015.
- Goodman A, Huh WK, Einstein MH. Cervical cancer screening: Risk assessment, evaluation, and management after screening. UpToDate [online serial]. Waltham, MA: UpToDate; reviewed June 2024.
- Gynecor. Resolve™ Comprehensive Colposcopy [website]. Glen Allen, VA: Gynecor; 2008. Available at: http://www.gynecor.com/home.aspx. Accessed August 18, 2008.
- Hartmann KE, Hall SA, Nanda K, et al. Screening for cervical cancer. Systemic Evidence Review No. 25. Prepared by the Research Triangle Institute/University of North Carolina Evidence-Based Practice Center for the Agency for Healthcare Research and Quality (AHRQ). Contract No. 290-97-0011, Task No. 3. Rockville, MD: AHRQ; January 2002.
- Haute Autorite de Sante (HAS). Evaluation of human papillomavirus (HPV) tests for primary screening of precancerous and cancerous lesions of the cervix and the role of p16/Ki67 dual immunostaining. Public Health Guidelines Summary. Saint-Denis, France; HAS; July 2019.
- Hawkes AP, Kronenberger CB, MacKenzie TD, et al. Cervical cancer screening: American College of Preventive Medicine practice policy statement. Am J Prev Med. 1996;12(5):342-344.
- Hoffman MS, Cavanaugh D. Cervical cancer: Screening and prevention of invasive disease. Cancer Control J. 1995;2(6):503-509.
- Hong Kong College of Obstreticians and Gynaecologists (HKCOG). Guidelines on the management of an abnormal cervical smear. HKCOG Guidelines No. 3. Hong Kong, China: HKCOG; December 1999.
- Huh WK, Ault KA, Chelmow D, et al. Use of primary high-risk human papillomavirus testing for cervical cancer screening: interim clinical guidance. Obstet Gynecol 2015;125:330-337.
- Huh WK, Cestero RM, Garcia FA, et al. Optical detection of high-grade cervical intraepithelial neoplasia in vivo: Results of a 604-patient study. Am J Obstet Gynecol. 2004;190(5):1249-1257.
- Hulstaert F, Arbyn M, Huybrechts M, et al. HTA of cervical cancer screening and HPV testing. KCE Reports Vol. 38B. Brussels, Belgium: Belgian Health Care Knowledge Centre (KCE); 2006.
- Institute for Clinical Systems Improvement (ICSI), Technology Assessment Committee. Liquid-based cervical cytology. Technology Assessment No. 076. Bloomington, MN: ICSI; August 2003.
- Institute for Clinical Systems Improvement (ICSI). Cervical cancer screening. Bloomington, MN: Institute for Clinical Systems Improvement (ICSI); August 2004.
- Institute for Clinical Systems Improvement (ICSI). HPV DNA testing for the screening and monitoring of cervical cancer. ICSI Technology Assessment No. 56. Bloomington, MN: ICSI; October 2005.
- Institute for Clinical Systems Improvement (ICSI). Management of initial abnormal pap smear. ICSI Healthcare Guideline. Bloomington, MN: Institute for Clinical Systems Improvement (ICSI); July 2004.
- Karnon J, Peters J, Platt J, et al. Liquid-based cytology in cervical screening: An updated rapid and systematic review and economic analysis. Health Technol Assess. 2004;8(20).
- Kjellberg L, Wiklund F, Sjoberg I, et al. A population-based study of human papillomavirus deoxyribonucleic acid testing for predicting cervical intraepithelial neoplasia. Am J Obstet Gynecol. 1998;19(6 Pt 1):1497-1502.
- Kobetz E, Seay J, Amofah A, et al. Mailed HPV self-sampling for cervical cancer screening among underserved minority women: Study protocol for a randomized controlled trial. Trials. 2017;18(1):19.
- Koliopoulos G, Martin-Hirsch P, Paraskevaidis E, Arbyn M. HPV testing versus cervical cytology for screening for cancer of the uterine cervix (Protocol for Cochrane Review). Cochrane Database Syst Rev. 2003;(4):CD004709.
- Krahn M, McLachlin M, Pham B, et al. Liquid-based techniques for cervical cancer screening: Systematic review and cost-effectiveness analysis. Technology Report No. 103. Ottawa, ON: Canadian Agency for Drugs and Technologies in Health (CADTH); 2008.
- Kurman RJ, Henson DE, Herbst AL, et al. Interim guidelines for management of abnormal cervical cytology. JAMA. 1994;271:1866-1869.
- Lapointe A, Erickson L, Brophy J. Adoption of liquid-based cytology: Technological evaluation. Executive Summary. Montreal, QC: Technology Assessment Unit of the McGill University Health Centre (MUHC); 2008.
- Li A, Li J, Austin RM, et al. Aptima HPV messenger RNA testing and histopathologic follow-up in women with HSIL cytology: A study emphasizing additional review of HPV-negative cases. Cancer Cytopathol. 2021;129(8):622-631.
- Li Y, Fu Y, Cheng B, et al. A comparative study on the accuracy and efficacy between Dalton and CINtec ® PLUS p16/Ki-67 dual stain in triaging HPV-positive women. Front Oncol. 2022;11:815213.
- Liaw KL, Glass AG, Manos MM, et al. Detection of human papillomavirus DNA in cytologically normal women and subsequent cervical squamous intraepithelial lesions. J Natl Cancer Inst. 1999;91(11):954-960.
- Lim AW, Hollingworth A, Kalwij S, et al. Offering self-sampling to cervical screening non-attenders in primary care. J Med Screen. 2017;24(1):43-49.
- Liu TY, Xie R, Luo L, et al. Diagnostic validity of human papillomavirus E6/E7 mRNA test in cervical cytological samples. J Virol Methods. 2014;196:120-125.
- Lofters AK, Vahabi M, Fardad M, Raza A. Exploring the acceptability of human papillomavirus self-sampling among Muslim immigrant women. Cancer Manag Res. 2017;9:323-329.
- Lorincz AT, Richart RM. Human papillomavirus DNA testing as an adjunct to cytology in cervical screening programs. Arch Path Lab Med. 2003;127:959-968.
- Manos MM, Kinney WK, Hurley LB, et al. Identifying women with cervical neoplasia: Using human papillomavirus DNA testing for equivocal Papanicolaou results. JAMA. 1999;281(17):1605-1610.
- Massad LS, Einstein MH, Huh WK, et al.; 2012 ASCCP Consensus Guidelines Conference. 2012 updated consensus guidelines for the management of abnormal cervical cancer screening tests and cancer precursors. J Low Genit Tract Dis. 2013;17(5 Suppl 1):S1-S27.
- Mayrand MH, Duarte-Franco E, Rodrigues I, et al; Canadian Cervical Cancer Screening Trial Study Group. Human papillomavirus DNA versus Papanicolaou screening tests for cervical cancer. N Engl J Med. 2007;357(16):1579-1588.
- Mazurec K, Trzeszcz M, Mazurec M, et al. Triage strategies for non-16/non-18 HPV-positive women in primary HPV-based cervical cancer screening: p16/Ki67 dual stain vs. cytology. Cancers (Basel). 2023;15(20):5095.
- McCrory DC, Matchar DB, Bastian L, et al. Evaluation of cervical cytology. Evidence Report/Technology Assessment No. 5. (Prepared by Duke University under Contract No. 290-97-0014.) AHCPR Publication No. 99-E010. Rockville, MD: Agency for Health Care Policy and Research; February 1999.
- Mears CJ, Heflin AH, Finkel MA, et al. Adolescents' responses to sexual abuse evaluation including the use of video colposcopy. J Adolesc Health. 2003;33(1):18-24.
- Medical Services Advisory Committee (MSAC). Human papillomavirus testing in women with cytological prediction of low-grade abnormality. MSAC Reference 12b. Canberra, ACT: MSAC; 2002.
- Medical Services Advisory Committee (MSAC). Liquid based cytology for cervical screening. Canberra, ACT: MSAC; 2002.
- Milbourne A, Park SY, Benedet JL, et al. Results of a pilot study of multispectral digital colposcopy for the in vivo detection of cervical intraepithelial neoplasia. Gynecol Oncol. 2005;99(3 Suppl 1):S67-S75.
- Minnesota Health Technology Advisory Committee (HTAC). New technologies for cervical cancer screening. St. Paul, MN: HTAC; January 1999.
- Minnesota Health Technology Advisory Committee (HTAC). Screening for cervical cancer: Recent advances. St. Paul, MN: HTAC; 2002.
- Mitchell MF, Schottenfeld D, Tortolero-Luna G, et al. Colposcopy for the diagnosis of squamous intraepithelial lesions: A meta-analysis. Obstet Gynecol. 1998;91:626.
- Modibbo F, Iregbu KC, Okuma J, et al. Randomized trial evaluating self-sampling for HPV DNA based tests for cervical cancer screening in Nigeria. Infectious Agents and Cancer. 2017;12:11.
- Muhlberger N, Sroczynski G, Esteban E, et al. Cost-effectiveness of primarily human papillomavirus-based cervical cancer screening in settings with currently established Pap screening: A systematic review commissioned by the German Federal Ministry of Health . Int J Technol Assess Health Care. 2008; 24(2):184-192
- Murali Krishna C, Sockalingum GD, Vidyasagar MS, et al. An overview on applications of optical spectroscopy in cervical cancers. J Cancer Res Ther. 2008;4(1):26-36.
- National Comprehensive Cancer Network (NCCN). Cervical cancer. NCCN Clinical Practice Guidelines in Oncology, Version.1.2014. Fort Washington, PA: NCCN; 2014.
- National Comprehensive Cancer Network (NCCN). Cervical cancer. NCCN Clinical Practice Guidelines in Oncology, Version 1.2017. Fort Washington, PA: NCCN; 2017.
- National Comprehensive Cancer Network (NCCN). Cervical cancer. NCCN Clinical Practice Guidelines in Oncology, Version 1.2018. Fort Washington, PA: NCCN; 2018.
- National Comprehensive Cancer Network (NCCN). Cervical cancer. NCCN Clinical Practice Guidelines in Oncology, Version 1.2020. Fort Washington, PA: NCCN; 2020.
- National Comprehensive Cancer Network (NCCN). Cervical cancer. NCCN Clinical Practice Guidelines in Oncology, Version 2.2015. Fort Washington, PA: NCCN; 2015.
- National Comprehensive Cancer Network (NCCN). Cervical cancer. NCCN Clinical Practice Guidelines in Oncology, Version 3.2019. Fort Washington, PA: NCCN; 2019.
- National Comprehensive Cancer Network (NCCN). Cervical cancer. NCCN Clinical Practice Guidelines in Oncology, Version 1.2021. Plymouth Meeting, PA: NCCN; 2021.
- National Comprehensive Cancer Network (NCCN). Cervical cancer. NCCN Clinical Practice Guidelines in Oncology, Version 2.2024. Plymouth Meeting, PA: NCCN; 2024.
- National Comprehensive Cancer Network (NCCN). Cervical cancer. NCCN Clinical Practice Guidelines in Oncology, Version 3.2024. Plymouth Meeting, PA: NCCN; 2024.
- National Institute of Clinical Excellence (NICE). Guidance on the use of liquid-based cytology for cervical screening. Technology Appraisal Guidance No. 69. London, UK: NICE; October 2003.
- Naucler P, Ryd W, Törnberg S, et al. Human papillomavirus and Papanicolaou tests to screen for cervical cancer. N Engl J Med. 2007;357(16):1589-1597.
- Nieminen P. Automated screening. Methods and techniques of cervical cancer screening. In: European Guidelines for Quality Assurance in Cervical Cancer Screening. Ch. 3.5. Munich, Germany: European Cervical Cancer Screening Network; April 24, 2003. Available at: http://www.cancer-network.de/cervical/index.htm. Accessed November 26, 2003.
- No authors listed. Cervical cancer. NIH Consensus Statement. 1996;14(1):1-38.
- No authors listed. Practice bulletin No. 168 summary: Cervical cancer screening and prevention.. Obstet Gynecol. 2016;128(4):923-925.
- No authors listed. Screening for cervical cancer: Recommendation statement. Am Fam Physician. 2019;99(4).
- Nobbenhuis MA, Walboomers JM, Helmerhorst TJ, et al. Relation of human papillomavirus status to cervical lesions and consequences for cervical-cancer screening: A prospective study. Lancet. 1999; 354(9172):20-25.
- Noorani HZ, Brown A, Skidmore B, Stuart GCE. Liquid-based cytology and human papillomavirus testing in cervical cancer screening. Technology Report Issue 40. Ottawa, ON: Canadian Coordinating Office for Health Technology Assessment (CCOHTA); 2003.
- Nuovo J, Melnikow J, Hutchison B, Paliescheskey M. Is cervicography a useful diagnostic test? A systematic overview of the literature. J Am Board Fam Pract. 1997;10(6):390-397.
- Onyango CG, Ogonda L, Guyah B, et al. Novel biomarkers with promising benefits for diagnosis of cervical neoplasia: A systematic review. Infect Agent Cancer. 2020;15(1):68.
- Ouh Y-T, Kim HY, Yi KW, et al. Enhancing cervical cancer screening: Review of p16/Ki-67 dual staining as a promising triage strategy. Diagnostics (Basel). 2024;14(4):451.
- Palusci VJ, Cyrus TA. Reaction to videocolposcopy in the assessment of child sexual abuse. Child Abuse Negl. 2001;25(11):1535-1546.
- Panther LA, Wagner KT, Proper J, et al. Use of human papillomavirus (HPV) typing to predict histologically-proven high-grade anal intraepithelial neoplasia (AIN) in HIV+ and HIV- men who have sex with men (MSM) with low-grade abnormalities on anal Pap smear. Abstract 640. Presented at the 7th Conference on Malignancies in AIDS and Other Immunodeficiencies: Basic, Epidemiologic and Clinical Research. Bethesda, MD: National Cancer Institute; April 28-29, 2003.
- Papillo JL, St John TL, Leiman G. Effectiveness of the ThinPrep Imaging System: Clinical experience in a low risk screening population. Diagn Cytopathol. 2008;36(3):155-160.
- Payne N, Chilcott J, McGoogan E. Liquid-based cytology in cervical cancer screening. A report by the School of Health and Related Research (ScHARR), the University of Scheffield, for the NCCHTA on behalf of NICE. Scheffield, UK: ScHARR; May 2000.
- Perkins RB, Guido RS, Castle PE, et al.; 2019 ASCCP Risk-Based Management Consensus Guidelines Committee. 2019 ASCCP risk-based management consensus guidelines for abnormal cervical cancer screening tests and cancer precursors. J Low Genit Tract Dis. 2020;24(2):102-131.
- Petry KU, Menton S, van Loenen-Frosch F, et al. Inclusion of HPV-testing in routine cervical cancer screening for women above 29 years in Germany: Results for 8466 patients. Br J Cancer. 2003;88:1570-1577.
- Phoolcharoen N, Kantathavorn N, Krisorakun W, et al. Agreement of self- and physician-collected samples for detection of high-risk human papillomavirus infections in women attending a colposcopy clinic in Thailand. BMC Res Notes. 2018;11(1):136.
- Policht FA, Song M, Sitailo S, et al. Analysis of genetic copy number changes in cervical disease progression. BMC Cancer. 2010;10:432.
- Rahatgaonkar V, Uchale P, Oka G. Comparative study of Smart Scope® visual screening test with naked eye visual screening and Pap test. Asian Pac J Cancer Prev. 2020;21(12):3509-3515.
- Ravarino A, Nemolato S, Macciocu E, et al. CINtec PLUS immunocytochemistry as a tool for the cytologic diagnosis of glandular lesions of the cervix uteri. Am J Clin Pathol. 2012;138(5):652-656.
- Rijkaart DC, Heideman DAM, Coupe VMH, et al. High-risk human papillomavirus (hrHPV) E6/E7 mRNA testing by PreTect HPV-Proofer for detection of cervical high-grade intraepithelial neoplasia and cancer among hrHPV DNA-positive women with normal cytology. J Clin Microbiol. 2012;50(7):2390-2396.
- Robinson WR. Screening for cervical cancer in patients with HIV infection and other immunocompromised states. UpToDate [online serial]. Waltham, MA: UpToDate; reviewed June 2024.
- Rodolakis A, Biliatis I, Symiakaki H, et al. Role of chromosome 3q26 gain in predicting progression of cervical dysplasia. Int J Gynecol Cancer. 2012;22(5):742-747.
- Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG) and the Royal Australian College of General Practitioners (RACGP). Joint statement on Pap smears. RANZCOG Statements. C-Gyn 13. East Melbourne, VIC: RANZCOG; November 2001.
- Ryan KJ, Berkowitz RS, Barbieri RL, et al. Kistner's Gynecology & Women's Health. 7th ed. St. Louis, MO: Mosby, Inc; 1999:93-120.
- Safaeian M, Wright TC, Stoler MH, et al. The IMPACT trial: Human papillomavirus, cervical cytology and histopathological results from the baseline and 1-year follow-up phase. Am J Obstet Gynecol. 2021;S20002-9378(21)00445-2.
- Salta S, Lobo J, Magalhaes B, et al. DNA methylation as a triage marker for colposcopy referral in HPV-based cervical cancer screening: A systematic review and meta-analysis. Clin Epigenetics. 2023;15(1):125.
- Sankaranarayanan R, Nene BM, Shastri SS, et al. HPV screening for cervical cancer in rural India. N Engl J Med. 2009;360(14):1385-1394.
- Saqi A, Gupta PK, Erroll M, et al. High-risk human papillomavirus DNA testing: A marker for atypical glandular cells. Diagn Cytopathol. 2006;34(3):235-239.
- Saslow D, Runowicz CD, Solomon D, et al. American Cancer Society guideline for the early detection of cervical neoplasia and cancer. CA Cancer J Clin. 2002;52(6):342-362.
- Saslow D, Solomon D, Lawson HW, et al. American Cancer Society, American Society for Colposcopy and Cervical Pathology, and American Society for Clinical Pathology screening guidelines for the prevention and early detection of cervical cancer. Am J of Clin Pathol. 2012;137(4):516-542.
- Schiffman M, Herrero R, Hildescheim A, et al. HPV DNA testing in cervical cancer screening: Results from women in a high-risk province of Costa Rica. JAMA. 2000;283:87-93.
- Schiffman M, Wacholder S. From India to the world -- a better way to prevent cervical cancer. N Engl J Med. 2009;360(14):1453-1455.
- Seppo A, Jalali GR, Babkowski R, et al. Gain of 3q26: A genetic marker in low-grade squamous intraepithelial lesions (LSIL) of the uterine cervix. Gynecol Oncol. 2009;114(1):80-83.
- Sherman ME, Lorincz AT, Scott DR, et al. Baseline cytology, human papillomavirus testing, and risk for cervical neoplasia: A 10-year cohort analysis. J Natl Cancer Inst. 2003;95:46-52.
- Siebers AG, Klinkhamer PJ, Grefte JM, et al. Comparison of liquid-based cytology with conventional cytology for detection of cervical cancer precursors: A randomized controlled trial. JAMA. 2009;302:1757.
- Sirovich BE, Feldman S, Goodman A. Cervical cancer screening tests: Evidence of effectiveness. UpToDate [serial online]. Waltham, MA: UpToDate; reviewed February 2014.
- Sirovich BE, Welch HG. Cervical cancer screening among women without a cervix. JAMA. 2004;291(24):2990-2993.
- Swedish Council on Technology Assessment in Health Care (SBU). Human papillomavirus testing in primary cervical cancer screening - early assessment briefs (ALERT). Stockholm, Sweden: SBU); 2001.
- Takacs P, Chakhtoura N, De Santis T. Video colposcopy improves adherence to follow-up compared to regular colposcopy: A randomized trial. Arch Gynecol Obstet. 2004;270(3):182-184.
- Taylor LA, Sorensen SV, Ray NF, et al. Cost-effectiveness of the conventional Papanicolaou test with a new adjunct to cytological screening for squamous cell carcinoma of the uterine cervix and its precursors. Arch Fam Med. 2000;9(8):713-721.
- Tice JA. Human papilloma virus testing in cervical cancer screening. Technology Assessment. San Francisco, CA: California Technology Assessment Forum (CTAF); February 11, 2004.
- Tidy JA, Brown BH, Healey TJ, et al. Accuracy of detection of high-grade cervical intraepithelial neoplasia using electrical impedance spectroscopy with colposcopy. BJOG. 2013;120(4):400-410; discussion 410-411.
- Tierney LM Jr, McPhee SJ, Papadakis MA, eds. Current Medical Diagnosis and Treatment. 39th ed. New York, NY: Lange Medical Books/McGraw-Hill; 2000:15, 79, 1278.
- U.S. Food and Drug Administration (FDA), Center for Devices and Radiological Health (CDRH). Luma cervical imaging system. Rockville, MD: FDA; March 16, 2006.
- U.S. Food and Drug Administration (FDA). Cobas HPV Test – P100020. Recently Approved Medical Devices. Rockville, MD: FDA; May 6, 2011.
- U.S. Preventive Services Task Force (USPSTF). Final Recommendation Statement: Cervical Cancer: Screening. Rockville, MD; August 2018.
- U.S. Preventive Services Task Force. Screening for cervical cancer. In: Guide to Clinical Preventive Services. Report of the U.S. Preventive Services Task Force. 3rd ed. Rockville, MD: Agency for Healthcare Research and Quality: 2003.
- U.S. Preventive Services Task Force. Screening for cervical cancer: Recommendations and rationale. Am Fam Physician. 2003;67(8):1759-1766.
- U.S. Preventive Services Task Force. Screening for cervical cancer. Report of the U.S. Preventive Services Task Force. Rockville, MD: Agency for Healthcare Research and Quality; April 2012.
- U.S. Preventive Services Task Force, Curry SJ, Krist AH, Owens DK, et al. Screening for cervical cancer: US Preventive Services Task Force recommendation statement. JAMA. 2018;320(7):674-686.
- Uhlig K, Earley A, Lamont J, et al. Fluorescence In Situ Hybridization (FISH) or Other In Situ Hybridization (ISH) Testing of Uterine Cervical Cells to Predict Precancer and Cancer. Technology Assessment Report. Project ID: CANC0511. Prepared by the Tufts Evidence-based Practice Center for the Agency for Healthcare Research and Quality, Contract No. HHSA 290 2007 10055 I. Rockville, MD: Agency for Healthcare Research and Quality (US); February 16, 2013.
- van Niekerk WA, Dunton CJ, Richart RM, et al. Colposcopy, cervicography, speculoscopy and Endoscopy. IAC Task Force Summary. Acta Cytol. 1998;42:33-49.
- van Rosmalen J, de Kok I, van Ballegooijen M. Cost-effectiveness of cervical cancer screening: Cytology versus human papillomavirus DNA testing. BJOG. 2012;119(6):699-709.
- Vassilakos P, Carrel S, Petignat P, et al. Use of automated primary screening on liquid-based, thin-layer preparations. Acta Cytologica. 2002;46(2):291-295.
- Verri A, Reza Jalali G, Cecchini G, et al. Significant progression of uterine cervical epithelial lesion accompanied by marked increase in 3q26 gene amplification. Lab Med. 2011;42(3):134-136.
- Vinals R, Jonnalagedda M, Petignat P, et al. Artificial intelligence-based cervical cancer screening on images taken during visual inspection with acetic acid: A systematic review. Diagnostics (Basel). 2023;13(5):836.
- Viviano M, Catarino R, Jeannot E, et al. Self-sampling to improve cervical cancer screening coverage in Switzerland: A randomised controlled trial. Br J Cancer. 2017;116(11):1382-1388.
- Wain GV. Automation in cervical cytology: Whose cost and whose benefit? Med J Austral. 1997;167:460-461.
- Walsh JC, Curtis R, Mylotte M. Anxiety levels in women attending a colposcopy clinic: A randomised trial of an educational intervention using video colposcopy. Patient Educ Couns. 2004;55(2):247-251.
- Wentzensen N, Clarke MA, Bremer R, et al. Clinical evaluation of human papillomavirus screening with p16/Ki-67 dual stain triage in a large organized cervical cancer screening program. JAMA Intern Med. 2019;179(7):881–888.
- Wentzensen N, Sherman ME, Schiffman M, Wang SS. Utility of methylation markers in cervical cancer early detection: Appraisal of the state-of-the-science. Gynecol Oncol. 2009;112(2):293-299.
- Willis BH, Barton P, Pearmain P, et al. Cervical screening programmes: Can automation help? Evidence from systematic reviews, an economic analysis and a simulation modelling exercise applied to the UK. Health Technol Assess. 2005;9(13):1-236.
- Winer RL, Tiro JA, Miglioretti DL, et al. Rationale and design of the HOME trial: A pragmatic randomized controlled trial of home-based human papillomavirus (HPV) self-sampling for increasing cervical cancer screening uptake and effectiveness in a U.S. healthcare system. Contemp Clin Trials. 2018;64:77-87.
- Workowski KA, Berman SM. Sexually transmitted treatment guidelines, 2006. Morbid Mortal Wkly Rep MMWR. 2006;55(RR11):1-94.
- Workowski KA, Bolan GA; Centers for Disease Control and Prevention. Sexually transmitted diseases treatment guidelines, 2015. MMWR Recomm Rep. 2015;64(RR-03):1-137.
- Wright TC Jr, Behrens CM, Ranger-Moore J, et al. Triaging HPV-positive women with p16/Ki-67 dual-stained cytology: Results from a sub-study nested into the ATHENA trial. Gynecol Oncol. 2017;144(1):51-56.
- Wright TC Jr, Cox JT, Massad LS, et al. 2001 Consensus Guidelines for the management of women with cervical cytological abnormalities. JAMA. 2002;287(16):2120-2129.
- Wright TC Jr, Denny L, Kuhn L, Goldie S. Use of visual screening methods for cervical cancer screening. Obstetrics and Gynecology Clinics. 2002;29(4).
- Wright TC Jr, Massad LS, Dunton CJ, et al; 2006 American Society for Colposcopy and Cervical Pathology-sponsored Consensus Conference. 2006 consensus guidelines for the management of women with abnormal cervical cancer screening tests. Am J Obstet Gynecol. 2007;197(4):346-355.
- Wright TC Jr, Stoler MH, Ranger-Moore J, et al. Clinical validation of p16/Ki-67 dual-stained cytology triage of HPV-positive women: Results from the IMPACT trial. Int J Cancer. 2022;150(3):461-471.
- Xu F, Ran T, Wei Q, et al. Diagnostic value of HPV E6/E7 mRNA in screening for cervical intraepithelial neoplasia grade 2 or worse: A systematic review and meta‑analysis. Oncol Lett. 2024;27(5):231.
- Yabroff KR, Saraiya M, Meissner HI, et al. Specialty differences in primary care physician reports of Papanicolaou test screening practices: A national survey, 2006 to 2007. Ann Intern Med. 2009;151(9):602-611.
- Yang H, Zhang X, Hao Z. The diagnostic accuracy of a real-time optoelectronic device in cervical cancer screening: A PRISMA-compliant systematic review and meta-analysis. Medicine (Baltimore). 2018;97(29):e11439.
- Yao Y-L, Tian Q-F, Cheng B, et al. Human papillomavirus (HPV) E6/E7 mRNA detection in cervical exfoliated cells: A potential triage for HPV-positive women. J Zhejiang Univ Sci B. 2017;18(3):256-262.
- Zhang J, Yang D, Cui X, et al. Performance of human papillomavirus E6/E7 mRNA assay for primary cervical cancer screening and triage: Population-based screening in China. Front Cell Infect Microbiol. 2022;12:935071.
