Abstract

Composite hemangioendothelioma (CHE) is a recently described vascular tumor of low-grade malignancy. We report a case of CHE in an 18-year-old woman who presented with a 2-month history of an enlarging palpable mass in the left axilla. Grossly, the excised tumor was relatively circumscribed, nodular, firm, and soft. It measured 6.0 x 4.5 x 4.0 cm. The cut surface revealed a whitish gray solid area and a dark red to tan cystic area containing necrotic material. Histologically, the tumor demonstrated variably intermixed benign and malignant vascular components. The benign components showed features of an arteriovenous malformation, capillary hemangioma, spindle cell hemangioma and cavernous hemangioma. The malignant components were composed of areas resembling retiform hemangioendothelioma, epithelioid hemangioendothelioma, Kaposiform hemangioendothelioma, and angiosarcoma. The angiosarcoma component showed a mixed epithelioid and spindle shaped cell morphology with moderate differentiation. A nearly imperceptible transition between the benign and malignant components was noted.

• Keywords: Hemangioendothelioma;Soft tissue