Retroperitoneal ganglioneuroma presenting as right renal mass.

A primary retroperitoneal ganglioneuroma was found in a 37-year-old woman on computed tomography, which revealed a homogeneous mass just above the right kidney. The tumor was resected through a transabdominal approach. The resected specimen measured 11 x 9 x 4.5 cm and weighed 270 g. The histologic examination showed that the lesion was a ganglioneuroma composed of both mature ganglion cells and nerve fibers.