Angiographic manifestations of soft-tissue and osseous hemangiopericytomas.

Hemangiopericytomas are rare vascular tumors and may originate wherever there are capillaries. So far, the author has found 341 cases of soft-tissue and 10 cases of osseous hemangiopericytomas. Only a few of these vascular tumors have been investigated angiographically. A review of 20 previously reported cases and 5 cases of his own, including a case of periosteal hemangiopericytoma, reveals that these are the only vascular tumors which present some characteristic angiographic features, regardless of their location or site of origin. Typically, a few feeder arteries enter the mass with radially arranged branching around and inside the tumor and a longstanding, well-demarcated tumor stain is seen.