Feasibility and Efficacy of Definitive Hypofractionated High-Dose Radiotherapy for Cutaneous Angiosarcoma of the Scalp.

Abstract

Cutaneous angiosarcoma is a rare but highly aggressive vascular tumor resistant to all treatment modalities available. The aim of this study was to analyze the treatment outcomes of patients who received definitive hypofractionated high-dose radiotherapy (RT) for angiosarcoma of the scalp. Between April 2008 and December 2014, 11 patients with histologically proven cutaneous angiosarcoma of the scalp visited our Department of Radiation Oncology, because dermatologists suggested that there was no indication for surgery in those cases. One patient rejected all radical treatments and the other 10 patients were treated by RT with curative intent along with chemotherapy or immunotherapy. Eight patients were treated with 6 - 12 MeV electron beams and the other 2 patients were treated with 4 MV X-ray Intensity Modulated Radiation Therapy (IMRT) and electron beams. The total irradiated dose was 63 - 75 Gy (median: 72.5 Gy) in 26 - 30 fractions, and the fraction size was 2.5 Gy in principle. The median age of the patients treated with RT was 80 years old (range: 73 - 91) and the median follow-up time was 16.5 months (range: 5.6 - 86.3). Four patients are still alive. A complete response (CR) was achieved in 10 patients (100%) and only one patient suffered local relapse 20 months after RT. Medians of overall survival (OS), progression-free survival (PFS), and local relapse-free survival (LRFS) were 38.7, 13.4, and 19.8 months, respectively. Local control rates were 100 and 75% at 1 and 2 years, respectively. Skin ulceration was CTCAE grade 2 in 5 patients (50%) and grade 3 in 5 (50%), alopecia was grade 2 in all patients (100%), but no patient developed grade 4 or more severe adverse events after RT. Hypofractionated high-dose RT was feasible and achieved excellent local control of cutaneous angiosarcoma in the elderly patients.