Incidence of contralateral germ cell testicular tumors in South Europe: report of the experience at 2 Spanish university hospitals and review of the literature.

PURPOSE The crude and cumulative incidence of contralateral germ cell testicular tumors (GCTTs) is between 1% to 5% and 3% to 6% at 10 to 15 years in previously reported studies. To evaluate the real incidence of a second GCTT in a southern European population the medical records of 623 patients with GCTT successfully treated between 1976 and 1993 at 2 university hospitals were reviewed. MATERIALS AND METHODS All patients had been treated with standard treatment strategies according to disease stage and diagnosis year. Contralateral biopsy at GCTT diagnosis was not performed in any patient. Only those with a survival of 1 year or greater were included. In addition to the imaging and biochemical (tumor markers) procedures used to diagnose disease relapse, physical examination of the contralateral testis and/or testicular ultrasound was done yearly. RESULTS At a median followup of 8.6 years (range 2 to 19.7) 6 patients (1%) had a contralateral GCTT, which was synchronous in 1 and metachronous in 5. The cumulative risk of a contralateral GCTT was 1.2% (95% CI 0.1% to 2.3%) at 15 years and it did not depend on the treatment for the first GCTT. CONCLUSIONS The incidence of contralateral GCTT in our series was lower than expected compared with other published series. This finding mirrors the lower incidence of GCTT in the general population in our country than in other areas with a higher incidence of contralateral GCTT. Therefore, contralateral testicular biopsy at initial diagnosis is not mandatory in our experience.