Hemangiopericytoma of the pancreas: report of a case and review of the literature.

Hemangiopericytoma is an uncommon vascular tumor with variable malignant potential. The origin, structure and function of pericytes remains controversial. Intra-abdominal hemangiopericytomas are highly aggressive soft tissue tumors with a great propensity for malignant transformation. We report on a case of hemangiopericytoma of the pancreas in a 53-year-old female presenting with abdominal pain. Ultrasonography and CT scan revealed a cystic tumor of the head of the pancreas. The patient underwent successful pancreaticoduodenal resection and is alive with no signs of recurrence 25 months following surgery. Ultrastructural studies are necessary to differentiate hemangiopericytomas from other sarcomas. Malignancy may be ascertained only in the presence of metastases or local recurrence. Routine surveillance is advocated.