[A case report of retroperitoneal malignant schwannoma].

A case of retroperitoneal malignant schwannoma is reported. The patient was a 66-years-old man who was referred to our clinic because of an abdominal lump. CT scan and renal arteriography pointed out right renal cyst, but the tumor was separate from the right kidney at operation. Pathological diagnosis of this retroperitoneal tumor was malignant schwannoma. After 10 months he developed local recurrence and had transabdominal excision. He has been doing well 12 months after the second operation. Thirty-one cases of retroperitoneal malignant schwannoma in Japan are reviewed.