Angiosarcoma arising in a bone infarct.

A primary angiosarcoma of the femur arose in continuity with a bone infarct in a 74-year-old man. The tumor, resected by amputation, had pleomorphic polygonal and spindle cells in solid and cystic patterns with focal vasoformative features. The immunohistochemical stains CD31, CD34, factor VIII-related antigen, and Ulex europeus corroborated the endothelial differentiation of the tumor. The patient died after developing pulmonary metastases. This is the oldest reported patient with a well-documented angiosarcoma associated with a bone infarct.