Bilateral testicular germ cell tumors: twenty-year experience at M. D. Anderson Cancer Center.

Abstract

The incidence of testicular carcinoma in the United States has increased significantly over the last two decades. Germ cell tumors form the majority of malignant testicular tumors. With advances in diagnosis and therapeutic approaches, germ cell tumors are now highly sensitive to treatment, providing long-term survival. It has been speculated that the incidence of bilateral germ cell tumors may increase due to the improved survival of patients with unilateral germ cell tumors. In this report, the authors present a study of bilateral germ cell tumors of the testis in men who were treated at The University of Texas M. D. Anderson Cancer Center over a 20-year period with emphasis on their incidence, histologic features, and clinical features. Between 1978 and 1999, 2431 patients with testicular germ cell tumors were treated at The University of Texas M. D. Anderson Cancer Center. Among these, 24 patients with bilateral germ cell tumors were identified. Clinical records and all available pathology slides of the tumors were reviewed. The overall incidence of bilateral germ cell tumors in the patients with testicular germ cell tumors was 1% (24 of 2431 patients). The incidence was 1.8% (14 of 776 patients) in patients with seminoma and 0.6% (10 of 1655 patients) in patients with nonseminomatous germ cell tumors. Patients with seminoma who were age </= 30 years at the time of initial diagnosis had a higher incidence of bilateral tumors compared with older men. Twenty of 24 patients with bilateral germ cell tumors had metachronous tumors, and 4 patients had synchronous tumors. Among the patients with metachronous tumors, 70% of second tumors occurred within 5 years; the longest interval between the first and second tumors was 15 years. The outcome of patients with bilateral germ cell tumors was excellent; only 1 of 24 patients died of metastatic disease. The overall incidence of bilateral testicular germ cell tumors was 1% in patients who were treated at The University of Texas M. D. Anderson Cancer Center over the past two decades. The incidence of bilateral germ cell tumors was related to the histologic type of the initial tumor and to the patient's age at initial presentation in patients with seminoma. Thus, patients in the second or third decade of life who presented with seminomas as their initial tumor were more likely to develop a second germ cell tumor compared with patients in the fourth or fifth decade of life. These findings have potentially important implications for clinical management by identifying a population of patients with germ cell tumors who are at risk of developing a second tumor and also for studying risk factors of bilateral germ cell tumors of the testis.