Renal Angiosarcoma

Angiosarcomas make up about 2% of all soft tissue sarcomas. Of all angiosarcomas, only about 5% involve the genitourinary tract. Accordingly, primary angiosarcoma of the kidney is an exceedingly rare tumor. It is most commonly seen in the 6th and 7th decades of life (mean age of 61 years) with a male predilection. The etiology of primary angiosarcoma of the kidney is not known; however, like liver, some cases have been linked to exposure to carcinogens like thorotrast, arsenic, and polyvinyl chloride. This image of renal angiosarcoma shows anastomosing vascular channels lined by minimally atypical endothelial cells with plump hyperchromatic nuclei.