Primary retroperitoneal cysts: report of an unusual case and a survey of the literature.

A case of a primary retroperitoneal cyst was associated with the chemical abnormalities of Cushing's disease and pheochromocytoma. Review of the literature failed to uncover a similar endocrinologically active retroperitoneal cyst. Primary retroperitoneal cysts, defined as those cysts lying in the retroperitoneal fatty tissue that have no apparent connections with any adult anatomical structure, are rare. These cysts are thought to arise from the mesonephros. They become symptomatic by virtue of their size or position. Diagnosis is suggested by an abnormal intravenous pyelogram and may be confirmed by arteriography. Treatment of choice is excision.