Epithelioid hemangioendothelioma of bone.

Neoplasms of bone can arise from any of the cellular elements that constitute osseous tissues. Although tumors of vascular origin are not uncommon, the vast majority are benign. A rare malignant vascular tumor--epithelioid hemangioendothelioma of bone--classifically affects young males and produces osteolytic lesions involving the cortex and cancellous bone of the lower extremities. We present a case with these findings, as well as such unusual findings as cervical spine instability and lesions affecting no fewer than 45 different bones. We conclude that epithelioid hemangioendothelioma should be investigated by skeletal survey because (1) osteolytic lesions involving more that 50% of the cortex present a serious risk for pathologic fracture and (2) the natural history of multicentric epithelioid hemangioendothelioma is more indolent than its solitary counterparts.