[Retroperitoneal schwannoma: a case report].

A 67-year-old man was admitted for a complaint of lumbago. The patient had had the three operations for the schwannoma in spinal cord at the Neurosurgical Department of our hospital. Magnetic resonance imaging (MRI) revealed a right infrarenal tumor by chance. The tumor compressed the right kidney and measured 6 x 5 cm in size. On the tentative diagnosis of the retroperitoneal tumor, the patient was referred to the department of urology in our hospital and the tumor was excised. The histological diagnosis of the removed retroperitoneal tumor was schwannoma, and was thought to be heterotopic recurrent schwannoma.