Abdominal hemangiopericytoma scintigraphically simulating an accessory spleen

Hemangiopericytoma is a soft tissue tumor composed histologically of pericytes of Zimmerman, which line capillaries. These neoplasms have been observed throughout the body in soft tissue and bone. Presented here is a case of abdominal hemangiopericytoma proven histologically that simulated an accessory spleen on a number of studies including Tc-99m sulfur colloid imaging.