Contralateral Testicular Biopsy in Men with Testicular Cancer

Testicular germ cell tumors (TGCTs) are an uncommon disease accounting for roughly 1% of newly diagnosed cancers in men worldwide. Incidence rates vary from 7 to 10 per 100 000 males in Europe and North America. Approximately 2–5% of patients with unilateral TGCT will also harbor germ cell neoplasia in situ (GCNIS) in the contralateral testicle, which may progress to cancer in at least 50% of individuals. The question of whether routine contralateral testicular biopsy should be performed in patients with testicular cancer to detect the presence of GCNIS remains controversial. Screening and treatment of GCNIS are warranted only if the patient's outcome will be improved and there will be little impact on testicular function. In this review, we evaluate current guideline recommendations and the issues concerning contralateral testicular biopsy. Patient summary: Among men with cancer in one testicle, about 2–5% will also have cells with cancerous potential, called germ cell neoplasia in situ (GCNIS), in the other testicle. This mini-review discusses issues related to routine biopsy of the other testicle and the risk factors and treatment options for GCNIS in men with testicular cancer.