We reviewed 13 cases of testicular tumors arising in cryptorchid, intra-abdominal testes. All types of germinal neoplasms were found, seminoma being the most common. Of the 13 patients 5 had undergone limited exploration previously, with no testis being identified and, thus, were thought to have had unilateral anorchism. The importance of a thorough exploration of the peritoneal cavity is emphasized.