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[A case of hemangiopericytoma in the pelvic retroperitoneum and review of literature of hemangiopericytoma in the retroperitoneal space in Japan].

Hemangiopericytoma is a rare capillary tumor that was first described and named by Stout and Murray in 1942. A case of hemangiopericytoma in the pelvic retroperitoneum is reported. The patient, a 57 year old man, was admitted because of dysuria. He underwent extirpation of the tumor with the rectum by low anterior resection. The pathological diagnosis was malignant hemangiopericytoma, and Adriamycin was administered to prevent recurrence or metastasis. He has been free from any recurrence or metastasis for the last eight months. Twenty cases of hemangiopericytoma in the retroperitoneum including our case, were collected from Japanese literature and reviews. Hemangiopericytoma, especially in the retroperitoneal space, should be regarded as a highly malignant tumor. Early aggressive therapy and long term follow up are recommended because the tumor characteristically produces late local recurrence and metastasis.