Management and outcome of bilateral testicular germ cell tumors: a 25-year single center experience.

Objectives: To analyze risk factors, management, histology, and outcome of bilateral testicular germ cell tumors (TGCT) based on a 25-year single center experience.

Methods: Out of 612 patients treated for TGCT between 1982 and 2007, 17 (3%) were found to have bilateral disease. Data of these patients were reviewed and analyzed.

Results: Eleven patients (65%) were identified with metachronous and 6 (35%) with synchronous bilateral TGCT. One patient had a cryptorchism in childhood. Patients with metachronous bilateral disease presented at lower stages than those with synchronous bilateral disease (stage I: 82% vs 33%, P = 0.02). In metachronous bilateral TGCT, the interval between the tumors ranged from 4 months to 25 years with a median of 47 months. The risk of developing a TGCT in the contralateral testicle was 26-fold higher than the a-priori risk for a healthy individual to develop TGCT. Overall, 74% of the bilateral tumors were seminomas and >50% of the patients had similar histology on both sides. After a median follow up of 121 months for patients with synchronous and 95 months for patients with metachronous bilateral TGCT, all patients were alive with no evidence of disease.

Conclusions: Most bilateral TGCT develop metachronously and are seminomas. Although patients with synchronous bilateral disease present at higher stages, both synchronous and metachronous bilateral TGCT carry a similar, excellent prognosis. Patients with unilateral TGCT require careful long-term monitoring of the remaining testicle due to a 26-fold increased risk of contralateral disease and a potentially long risk interval of up to 25 years.