RESUMEN
A rare case is presented where a dysgenetic testis with microinvasive carcinoma in situ (CIS, also known as intratubular germ cell neoplasm of unclassified type [IGCNU] and testicular intraepithelial neoplasia [TIN]) with microinvasion to rete testis and the interstitial tissue was found in a 32-year-old man presenting with mild scrotal pain and ultrasonic testicular microlithiasis. Knowledge of the association of ultrasound and CIS is important to diagnose patients at the stage prior to development of an overt germ cell tumor. The patient had three of four disorders considered symptoms of the testicular dysgenesis syndrome (TDS): a dysgenetic left testicle with CIS, a mild left-sided cryptorchidism (high positioned scrotal hypotrophic testis) and a slightly reduced semen quality. Therefore, it should be kept in mind that a patient with one TDS symptom may harbour the other, even CIS or testicular cancer. Accordingly, patients with one TDS symptom ought to be examined for the presence of the others, and if more that one is present, extra concern is warranted.