A phase II trial of carboplatin, 300 mg/m2 day 1, and cisplatin, 50 mg/m2 days 2 and 3 every 4 weeks for six cycles, was performed in 42 previously untreated patients with residual disease after primary laparotomy. Overall, 79% of patients had primary residual tumor larger than 2 cm. The overall pathologic response rate (pathologic complete response [PCR] plus partial response [PPR]) in 37 evaluable patients was 62%, and in PCRs was 22%. Of the responding patients, 78% had primary residual tumor larger than 2 cm. The toxicity was cumulative but manageable, with thrombocytopenia being the main reason for dose reduction. Dose-limiting nephrotoxicity and neurotoxicity occurred in 22% and 7% of the patients, respectively. Combined high-dose platinum as a "single agent" appears to be as active as combination chemotherapy containing cisplatin, and the treatment is feasible. Further clinical trials of this combination alone or combined with other drugs are warranted.