Epithelioid Angiosarcoma in Femur: A Case Presentation.

Primary malignant vascular tumors which constitute less than 1% of the primary bone tumors are very rarely encountered. Epithelioid angiosarcoma is a very uncommon subtype of angiosarcomas presenting with an epithelioid phenotype and mimicking carcinomas clinically. These tumors select mostly extra-skeletal locations but rarely bones as their medium. A 31-year-old male patient applied to our clinic with a nonspecific left hip pain. X-ray evaluation revealed a cystic expansile mass in the trochanteric region of the femur extending to the femoral neck. Computed tomography examination proved that the mass was cystic and 7 cm in its greatest width and contained septum. Moreover, magnetic resonance imaging examination was reported as a mass resembling aneurysmal bone cyst. The final diagnosis of epithelioid angiosarcoma was made by histological examination and biopsy of the mass. The excised specimen was examined further to verify the preoperative diagnosis.