Aetna considers low-dose radiation (superficial or interstitial) medically necessary as an adjunctive therapy immediately following excisional surgery (within 7 days) in the treatment of keloids where medical necessity criteria for keloid removal are met.  See CPB 0031 - Cosmetic Surgery for medically necessary indications for keloid removal.

Radiation therapy is considered medically necessary for preventing heterotopic ossification in persons identified as being at high risk (previous heterotopic ossification, ankylosing spondylitis, diffuse idiopathic skeletal hyperostosis or spinal stenosis, unlimited hip motion preoperatively, and head injury).

See also: CPB 800 - Dupuytren Contracture: Treatments; and CPB 231 - Grenz Ray Therapy for Skin Disorders.

Keloids are benign fibrous growths that arise from proliferation of dermal tissue following skin injury.  Conventional treatment options for keloids are occlusive dressings (including silicone-based materials), compression therapy, intra-lesional injections of corticosteroid, cryosurgery, and excision surgery.  Newer modalities include the carbon dioxide laser, Nd:YAG laser, argon laser, pulsed dye laser, intra-lesional interferon-gamma and interferon-alfa 2b, and cultured epithelial autografts.  In general, laser excision results in similar recurrence rates as conventional surgery.  However, the incidence of recurrence is high following conventional forms of treatment.  In particular, the recurrence rate of keloids after excision alone has been reported to be between 45 % and 100 %.  It has also been reported that the recurrence rate following excision is higher with keloids forming at infected sites and in patients with a family history of keloids.  The likelihood of recurrence does not appear to be affected by the person's age, sex, or ethnicity; keloid size or location; individual keloid history; or prior therapy.

Post-operative radiation therapy has been shown to be safe and effective in reducing recurrence of keloids after excision surgery.  In addition, it has been reported that post-operative radiation therapy is a simpler treatment modality with better patient compliance than post-operative corticosteroid injections.

Kal and Veen (2005) stated that for successful prevention of recurrence of keloids after surgical excision, a relatively high-dose must be applied in a short overall treatment time.  The optimal treatment probably is an irradiation scheme resulting in a biologically effective dose (BED) value of at least 30 Gy.  A BED value of 30 Gy can be obtained with, for instance, 1 single acute dose of 13 Gy, 2 fractions of 8 Gy, or 3 fractions of 6 Gy, or 1 single dose of 27 Gy at low-dose rate.  The radiation treatment should be administered within 2 days following surgery.

Ogawa and colleagues (2009) noted that keloids are best treated by a combination of surgery and post-operative radiation therapy, although randomized controlled trials testing this are still lacking.  However, plastic surgeons tend to avoid radiation therapy for keloids for fear of inducing malignant tumors.  Thus, the authors searched for previous reports of associations between carcinogenesis and keloid radiation therapy, and examined the evidence-based opinions of radiation oncologists regarding the acceptability of using radiation to treat keloids.  A computerized literature search was carried out using PubMed that included citations from Medline and PubMed Central between 1901 and March of 2009.  The following search terms were used: "keloid(s)," "hypertrophic scar(s)," "radiation," "radiation therapy," "radiotherapy," "carcinogenesis," "carcinoma," "cancer," "complications," and "side effects."  Moreover, the references for each report were also retrieved.  The authors located 5 cases of carcinogenesis (i.e., fibrosarcoma, basal cell carcinoma, thyroid carcinoma, and breast carcinoma) that were associated with radiation therapy for keloids.  However, it was unclear if an appropriate dose of radiation was used and whether sufficient protection of surrounding tissues was provided.  Moreover, a questionnaire study of radiation oncologists around the world revealed that approximately 80 % considered radiation to be acceptable for treating keloids.  The authors concluded that the risk of carcinogenesis attributable to keloid radiation therapy is very low when surrounding tissues, including the thyroid and mammary glands, especially in children and infants, are adequately protected, and that radiation therapy is acceptable as a keloid treatment modality.

Heterotopic ossification (HO) is an overgrowth of bone that frequently occurs after a bone fracture (break).  It commonly occurs in patients who have fractured bones of the spine, hip, or elbow. It causes pain and disability. Radiation therapy is a local treatment modality that works by damaging the DNA of cells. 

Based on the clinical evidence, preoperative or post operative radiation therapy has been proven to be effective in preventing heterotopic ossification for patients identified as being at risk (previous heterotopic ossification, ankylosing spondylitis, diffuse idiopathic skeletal hyperostosis or spinal stenosis, unlimited hip motion preoperatively, and head injury).