Forty-five patients with advanced non-small cell lung cancer were randomly allocated to receive vindesine (3 mg/m2 every week) plus either high-dose cisplatin (120 mg/m2 every 4 weeks) or low-dose cisplatin (80 mg/m2 every 3 weeks). All patients were previously untreated. The response rate for the high-dose regimen of cisplatin was 39% (9/23) and that for the low-dose regimen of cisplatin was 33% (7/21); the difference was not statistically significant. Only one patient treated with high-dose cisplatin achieved complete response, lasting 6.5 months. The median duration of response was 5.6 months (range, 2.7-7.7) in the high-dose cisplatin group and 6.8 months (range, 1.9-8.9) in the low-dose cisplatin group. The median survival times for the 23 patients treated with the high-dose regimen of cisplatin and for the 21 patients treated with the low-dose regimen of cisplatin were 9.0 and 10.8 months, respectively. Significantly more azotemia occurred in the high-dose cisplatin group than in the low-dose cisplatin group (P less than 0.05). Combination chemotherapy with cisplatin and vindesine showed significant antitumor activity in patients with non-small cell lung cancer. However, the high-dose regimen of cisplatin did not result in a significantly better response rate or survival advantage, and was associated with greater toxicity.