[A retroperitoneal mass in a young patient]

A tumor of germinal cells should be considered in the differential diagnosis of a retroperitoneal mass in a young patient. Although, this kind of tumors are relatively uncommon, inducing less than 1% of all the tumors in the masculine sex, very often they may present as a retroperitoneal mass clinically characterized by a lumbar pain that sometimes may simulate a renal colic. Occassionally, physical examination of the testis may reveal a mass. Moreover, even in advanced stages the prognosis of germ cell tumor is favorable, and there are a series of tumor markers very helpful for the diagnosis and follow up of the tumor. We report a patient with a retroperitoneal mass presenting clinically as a renal colic.