Bilateral testicular germ cell tumours: an increasing incidence and prevention by chemotherapy.

Of 120 patients with germ cell tumours of the testis, 6 (5%) developed contralateral tumours; 63 patients received cisplatin-based combination chemotherapy for metastatic disease and none developed contralateral disease. By contrast, of 57 patients treated with orchiectomy alone or abdominal radiotherapy, 5 (8.8%) developed contralateral disease.