Radical radiotherapy for localized cutaneous angiosarcoma of the scalp.

Angiosarcoma is a rare but highly aggressive sarcoma of mesenchymal origin with a high mortality rate. Due to its rarity, there are very limited reports on the clinical outcomes of angiosarcoma treated with radical radiotherapy. The aim of the present study was to evaluate the efficacy and feasibility of treating patients with radiotherapy for cutaneous angiosarcoma localized to the scalp at The University of Tokyo Hospital (Tokyo, Japan). The present study analyzed 15 consecutive patients treated for cutaneous angiosarcoma of the scalp with radiotherapy between June 2008 and January 2020. All patients were treated with 70 Gy of irradiation split into 35 fractions, focused on the lesion, including 9 patients who received total scalp radiotherapy. The median follow-up period in all patients was 9.7 months. The median overall survival (OS) time was 20.7 months, and the 1-, 2- and 5-year OS rates were 56.2, 28.1 and 9.4%, respectively. At the time of analysis, 13 patients (86.7%) developed recurrence. Among these 13 patients, the first site of recurrence was the scalp as local recurrence in 7 patients (46.7%), parotid recurrence in 2 patients (13%) and distant metastasis in 4 patients (26.7%). No patient exhibited grade 3-5 radiation-induced late toxicity. Therefore, the present study revealed the clinical outcomes of radical radiotherapy for cutaneous angiosarcoma of the scalp.