[A case of retroperitoneal neurinoma]

Retroperitoneal neurinoma is a rare disease, although retroperitoneal tumor is rather common. A 40-year-old man without any clinical symptoms was admitted to our hospital for a medical examination. Ultrasonogram demonstrated a cystic mass over the right kidney. This cystic mass was suggested to be a right adrenal tumor by CT scan and angiogram. All of the laboratory data including endocrinological data were within the normal limits. Under the diagnosis of right non-functioning adrenal tumor, an operation was performed through a right lumbal incision. A round and tennis ball sized tumor with a fibrous capsule was identified and freed from the right kidney and the right adrenal gland, and the tumor was extirpated uneventfully. The surgical specimen was 9.5 X 8.0 X 6.5 cm in size, 260 g in weight, and the histological diagnosis was neurinoma (Antoni-B type).