Congenital hemangiopericytoma: two case reports

Congenital hemangiopericytoma is a rare tumor consisting of capillaries surrounded by pericytes. Only histologically can the tumor be distinguished from other vascular hamartomas. For a long time the congenital type was considered benign; however, metastases have recently been described. A histologic diagnosis of all soft-tissue sarcomas should be made. We describe two patients with congenital hemangiopericytomas in whom the diagnosis was not suspected until after histologic examination. Long-term follow-up is indicated.