Radiation therapy for angiosarcoma of the scalp: treatment outcomes of total scalp irradiation with X-rays and electrons.

Wide surgical excision is the standard treatment for angiosarcoma of the scalp, but many patients are inoperable. Therefore, we investigated the outcome of radiation therapy for angiosarcoma of the scalp. Seventeen patients with angiosarcoma of the scalp underwent radiation therapy with total scalp irradiation. Four patients had cervical lymph node metastases, but none had distant metastases. A median initial dose of 50 Gy in 25 fractions was delivered to the entire scalp. Subsequently, local radiation boost to the tumor sites achieved a median total dose of 70 Gy in 35 fractions. Fourteen of the 17 patients developed recurrences during the median follow-up period of 14 months after radiation therapy; 7 had recurrences in the scalp, including primary tumor progression in 2 patients and new disease in 5, and 12 patients developed distant metastases. The primary progression-free, scalp relapse-free, and distant metastasis-free rates were 86, 67, and 38 % at 1 year and 86, 38, and 16 % at 3 years, respectively. Thirteen patients died; the overall and cause-specific survival rates were both 73 % at 1 year and 23 and 44 % at 3 years, respectively. The median survival time was 16 months. There were no therapy-related toxicities ≥ grade 3. Total scalp irradiation is safe and effective for local tumor control, but a dose of ≤ 50 Gy in conventional fractions may be insufficient to eradicate microscopic tumors. For gross tumors, a total dose of 70 Gy, and > 70 Gy for tumors with deep invasion, is recommended.