Screening for carcinoma-in-situ of the testis.

Germ cell neoplasia detected at the preinvasive stage of carcinoma-in-situ (CIS) can be cured by orchidectomy or by localized irradiation of the testis. Therefore, screening for carcinoma-in-situ of the testis has been applied to groups of individuals known to have an increased risk of testicular cancer. A high (5.5%) incidence of CIS was found in the contralateral testis of men with a unilateral cancer of the testis. An increased incidence of CIS was also found among men with a history of cryptorchidism. We recommend routine screening for CIS of the testis in both groups of men. The role of screening for CIS among subfertile men remains to be elucidated.