BACKGROUND: Survival of pediatric patients with malignant germ cell tumors has improved dramatically with the use of cisplatin-based chemotherapy, though patients are at high risk of significant long-term complications. In a prospective study, carboplatin was substituted for cisplatin in an attempt to minimize nephro- and oto-toxicities, while achieving excellent disease-free survival. PROCEDURE: All consecutive patients with malignant germ cell tumors at The Children's Hospital of Philadelphia were treated between 1989 and 1998. After pathologic confirmation of disease and pretreatment evaluation of pulmonary, renal, and otologic function, patients received etoposide 150 mg/m(2) days 1, 2, 3; carboplatin 600 mg/m(2) day 2; and bleomycin 10 mg/m(2) day 3 for at least four courses. RESULTS: Twenty-three patients were entered for study, and were available for evaluation. All patients achieved either a complete or partial remission following therapy with surgery and chemotherapy. With a median of 58 months of follow-up, overall survival is 91% and event-free survival is 87%. Therapy was given as an outpatient, and well tolerated, with 20 admissions for fever and neutropenia. Ototoxicity and nephrotoxicity, when evaluated, have been extremely limited. Three patients, all with stage III disease, have relapsed; one of these remains alive and disease free. CONCLUSIONS: Carboplatin can successfully substitute for cisplatin during the treatment of pediatric germ cell tumors without sacrificing response or survival. Long-term effects, especially nephrotoxicity and ototoxicity, were rare or mild among the small number of patients evaluated. Carboplatin appears to be a safe and efficacious alternative in the treatment of germ cell tumors, and should be considered as primary therapy for pediatric patients.