Management of the contralateral testis in patients with testicular germ cell cancer.

Patients with testicular germ cell tumours (TGCT) are at increased risk of developing a tumour in the contralateral testis. Such a tumour may be preceded by carcinoma in situ (CIS), which is more common in patients with infertility, atrophic testis or a history of cryptorchism. Of 1219 patients with TGCT seen at the Royal Marsden Hospital between 1962 and 1984 in whom the contralateral testis was managed by surveillance, 38 (3.1%) developed a second tumour and 8 died of germ cell tumours. Seventeen of 26 assessable patients (65%) exhibited at least one of the known aetiological risk factors for carcinoma in situ. Diagnosis of carcinoma in situ may lead to more appropriate management of the contralateral testis.