A case of angiosarcoma of the breast.

This is a case report of a 20-year-old woman who had primary angiosarcoma of the left breast, with metastases to the spleen and ovary. Eight months after detecting a mass in her breast, she underwent mastectomy with biopsy of the ipsilateral axillary lymph nodes, splenectomy and bilateral oophorectomy. Five months after the operation, the patient succumbed to lung metastases. Angiosarcoma of the breast is a rare condition with a poor prognosis, and there are no established chemotherapeutic regimens as yet. Immunohistochemical staining for endoglin, known to be expressed mainly on the surface of endothelial cells, was positive. This suggests the possibility of treating angiosarcoma with anti-endoglin monoclonal antibodies.