Benign retroperitoneal schwannoma mimicking an adrenal mass.

Adrenal tumors are frequently incidental discoveries, and the therapy for them is the subject of controversial discussions. We report herein on such an incidentaloma, which proved to be a benign retroperitoneal schwannoma. A 48-year-old female with an unclear adrenal mass underwent retroperitoneoscopic tumor extirpation. A well-defined tumor that displaced the adrenal gland and adhered firmly to only one retroperitoneal nerve was discovered. The en bloc resection was performed without problem. The histopathologic examination revealed a benign schwannoma. Retroperitoneal schwannomas can mimic a multitude of different conditions. Because imaging methods frequently do not yield distinct results, quite often only the operative exploration can establish a definitive diagnosis. In a case of unclear retroperitoneal findings, an endoscopic extirpation should be considered.