The role of radiation therapy in melanoma.

Although melanoma was historically thought to be radiation resistant, there are limited data to support the use of adjuvant radiation therapy for certain situations at increased risk for locoregional recurrence. High-risk primary tumor features include thickness, ulceration, certain anatomic locations, satellitosis, desmoplastic/neurotropic features, and head and neck mucosal and anorectal melanoma. Lentigo maligna can be effectively treated with either adjuvant or definitive radiation therapy. Some retrospective and prospective randomized studies support the use of adjuvant radiation to improve regional control after lymph node dissection for high-risk nodal metastatic disease. Consensus on the optimal radiation doses and fractionation is lacking.