Radiation-Associated Breast Angiosarcoma.

Radiation-associated breast angiosarcomas are rare following breast-conserving surgery. These angiosarcomas are considered adverse events associated with radiation therapy and are characterized by a high risk of both local and distant recurrence, even after complete resection. Despite this, there is currently no established standard treatment for them. The patient was a 70-year-old woman who had breast-conserving surgery for right breast cancer 10 years before presentation. She was followed up for 10 years after receiving 50 Gy of residual breast irradiation and an aromatase inhibitor for 5 years. During follow-up, a painless purplish area with induration, measuring 10 cm by 5.4 cm, was noted on the right nipple. A skin biopsy confirmed hemangiosarcoma. Treatment included surgery with a 2.0 cm margin from the area, followed by skin excision and total mastectomy. A final diagnosis of radiation-associated breast angiosarcoma was made. Radiation-associated breast angiosarcoma is a rare disease with a poor prognosis that lacks standard treatment. An aggressive skin biopsy should be considered when skin findings such as purpura are seen after breast cancer radiotherapy, as in this case.