Postradiation angiosarcoma of the small intestine: a case report and review of literature.

Postradiation angiosarcoma is typically a high-grade sarcoma that presents mainly in the skin and superficial tissues. Postradiation angiosarcoma arising in the small intestine is rare with only 11 cases documented in the English-language literature. Herein, we report a postradiation angiosarcoma of the small intestine 9 years after radiotherapy for uterine cervical adenocarcinoma. The patient presented with symptoms of intestinal obstruction. At exploratory laparotomy, tumor nodules involved the small bowel. Microscopically, the neoplasm was composed of spindled and epithelioid cells arranged in solid aggregates and focally forming vascular channels. The diagnosis of angiosarcoma was confirmed immunohistochemically by tumor cell expression of CD31, CD34, and factor VIII-related antigen. The patient died 10 months after laparotomy. The diagnosis of PRA should be entertained for any poorly differentiated neoplasm arising in a previously irradiated site. The correct diagnosis of PRA depends upon histomorphologic identification of vascular differentiation, coupled with immunohistochemical expression of endothelial-related markers.