In the present multicentre randomized phase II trial, the activity and toxicity of three platinum-based combination regimens for the treatment of advanced non-small-cell lung cancer (NSCLC) were evaluated. The three regimens were: MVP (mitomycin-C 6 mg m(-2) on day 1, vindesine 3 mg m(-2) on days 1 and 15, and cisplatin 80 mg m(-2) on day 1 every 28 days), PIN (cisplatin 80 mg m(-2) day 1, ifosfamide 3 g m(-2) day 1 and vinorelbine 25 mg m(-2) day 1 and 8 every 21 days) and CaN (carboplatin 350 mg m(-2) day 1 and vinorelbine 25 mg m(-2) days 1 and 8 every 28 days). A total of 140 chemotherapy-naive patients entered the study; 49 patients were treated with MVP, 48 with PIN and 43 with CaN. Sixty-seven per cent of the patients had stage IV disease. Response rates, calculated on an 'intention to treat' basis, were as follows: MVP, 14.3% (95% CI 5.94-27.2%); PIN, 16.7% (95% CI 7.4-30.2%); and CaN, 14% (95% CI 5.3-27.9%). The overall median survivals were 256, 269 and 243 days for patients treated with MVP, PIN and CaN respectively. Myelosuppression was the most frequent toxicity: grade 3-4 leucopenia was observed in 14.3%, 25% and 18.6% of patients treated with MVP, PIN and CaN respectively. This multicentre phase II randomized trial shows that MVP, PIN and CaN can be administered on an outpatient basis with acceptable toxicities. Unfortunately, the three regimens showed an activity significantly lower than that reported in previous single-institution phase II trials.