The incidence and management of metachronous testicular germ cell tumors in patients with extragonadal germ cell tumors

ObjectivesThe optimal management of extragonadal germ cell tumor (EGGCT) and metachronous testicular germ cell tumor (MTGCT) has not been determined.Patients and methodsFifty-one consecutive patients with EGGCT were identified. Testicular palpation or ultrasonography to rule out a primary testicular tumor was performed. Pretreatment testicular biopsies were not performed. The incidence and outcome of MTGCT, and the prognosis of EGGCT were evaluated.ResultsTwenty-five and 26 patients, respectively, had mediastinal and retroperitoneal EGGCT. Fourteen and 37 patients, respectively, had seminoma and nonseminoma. Five patients developed MTGCT in patients with retroperitoneal EGGCT. The median interval from the primary treatment for EGGCT to MTGCT diagnosis was 64 months (range 15–120). The cumulative risk of developing MTGCT was 8.3% at 6 y. Five patients underwent an orchiectomy and have survived in the 16-months median follow-up period (range 4–30). Among the patients with seminomatous and nonseminomatous EGGCT, the 5-year survival rate was 84.6% and 78.3%, respectively. Among the patients with retroperitoneal and mediastinal nonseminomatous EGGCT, the 5-year survival rate was 94.7% and 58.8%, respectively.ConclusionsThe prognosis of EGGCT without testicular biopsies was sufficient. EGGCT patients, especially retroperitoneal EGGCT, need long-term follow-up for MTGCT.