Retroperitoneal ganglioneuroma: a case report.

A primary extra-adrenal retroperitoneal ganglioneuroma was found incidentally in a 17-year-old boy during a series of examinations for hematopyuria. Computed tomography and magnetic resonance imaging revealed a homogenous mass located between the right proximal ureter and the inferior vena cava just below the right kidney. Subtotal resection of the tumor was performed through a transabdominal approach. The resected specimen measured 8.5 x 6 x 5.5 cm and weighed 70 g. Histological examination showed that the lesion was an extra-adrenal retroperitoneal ganglioneuroma composed of mature ganglion cells and nerve fibers without any malignant features. The patient has shown no signs of recurrence in the 4 months after surgery. We provide a review of the Japanese literature on extra-adrenal retroperitoneal ganglioneuroma and also discuss the clinical features of this tumor.