A Case of Primary Orbital Hemangiopericytoma

ABSTRACT

Hemangiopericytoma is a rare kind of soft tissue tumor. It usually attacks adults without distinction of sex. In most cases, slowly enlarging mass is a chief complaint of patient and symptoms such as tenderness and pain are rare. It is known to frequently attack the lower extremity, especially thigh, pelvic fossa and retroperitoneum, and in rare cases, trunk and upper extremity. In this paper, we report a 47-ear-old female patient with primary orbital hemangiopericytoma in right upper eyelid. Before operation, we found oval-shaped tumor which had a vivid boundary, from the orbital CT and MRI. During the operation, we found an ovoid mass(about 2.6 X 2 X 1 cm) surrounded by a thin capsule on the upper eyelid medial portion. By H&E stain after operation, we found a "staghorn" configuration- haped blood vessel distribution. In an immunohistochemical stain test using factor VIII-related antigen, this tumor was not originated from endotheliumm, but from vessel. In Gomori's reticulin stain test, we confirmly diagnosed these tumor cells as hemangiopericytoma, since these cells were arranged around the vessel, surrounded by a reticulin fiber. She had no symptom of recurrence after operation. As hemangiopericytoma is not frequently developed in an orbital area, we report this case in this paper.