Radiotherapy of classic Kaposi's sarcoma in Taiwan, an area where classic Kaposi's sarcoma is not prevalent

Background: Classic Kaposi's sarcoma (KS), a neoplastic disease of vascular endothelial cells of the skin, is relatively prevalent in Eastern Europe and the Mediterranean region and radiation is one of the standard therapies. The clinical presentation and treatment results of classic KS from other regions have rarely been reported. Patients and Methods: Between 1994 and 2006, patients who had histologically confirmed KS and no immunodeficiency status due to human immunodeficiency virus infection or organ transplantation, and were treated with radiotherapy at Department of Oncology, National Taiwan University Hospital, Japan, were reviewed. Results: A total of 17 classic KS patients, with a median age of 69 years, were studied over a period of 12 years. All classic KS lesions involved lower extremities. Radiotherapy was delivered with either a ⁶⁰Co unit or a linear accelerator, with the most commonly prescribed treatment being 3 Gy per fraction to a total dose of 39 Gy. In addition, several techniques using bolus were adopted to improve the radiation distribution over the skin of lower extremities. All irradiated KS lesions responded, with a complete response rate of 76%. The overall survival and progression-free survival rates of the group at 5 years were 85% and 58%, respectively. Conclusion: Radiation therapy for classic KS patients in a non-prevalent area, such as Taiwan, is safe and effective.