Paget's disease of the nipple and angiosarcoma of the breast following excision and radiation therapy for carcinoma of the breast.

We report a case of bilateral angiosarcomas developing in breasts after radiation therapy. The angiosarcomas developed 7 years after the first dose and 3 years after the last dose of radiation. In addition, Paget's disease of the nipple was diagnosed in the right breast. c-neu overexpression was noted in the adenocarcinoma but not in the angiosarcoma. Neither tumor was immunoreactive for c-k-ras. The oncogenic expression of the radiation-induced angiosarcoma was different from that of the radiation-resistant adenocarcinoma. The simultaneous occurrence of angiosarcoma and Paget's disease of the nipple has not been reported previously. The importance of recognizing Paget's disease in post-irradiated breasts and complications of breast conservation therapy are stressed.