Cisplatin-based chemotherapy changes the incidence of bilateral testicular cancer.

Abstract

The introduction of cisplatin-based chemotherapy has remarkably increased the survival of testicular cancer patients. With this success, the concern for a contralateral testicular tumor has increased. The aim of this study was to investigate whether the risk for contralateral testicular tumor development was influenced by cisplatin-based chemotherapy. The incidence of a contralateral testicular tumor among 365 consecutive patients with a nonseminoma testicular tumor, diagnosed in the period 1980 and 1995, was established and related to previous therapy. Eleven of 365 men (3%) developed a contralateral testicular tumor. After a total of 2403 person-years at risk, 4 of 225 chemotherapy-treated patients (1.8%) developed a contralateral testicular tumor, and 7 of 140 patients (5%) treated with orchidectomy alone developed a contralateral tumor. In comparison to this surveillance subgroup, patients previously treated with chemotherapy have a relative risk of 0.30 to develop a second testicular tumor. In Dutch men with a nonseminoma testicular tumor, the incidence of a contralateral testicular tumor is 3%, which is 60-fold the expected incidence rate of testicular cancer. A three times lower incidence rate of a contralateral testicular tumor was found in the chemotherapy subgroup compared with those on surveillance. This supports the hypothesis that cisplatin-based chemotherapy may eradicate carcinoma in situ or early testicular cancer.