This trial was carried out to evaluate the therapeutic benefit of the addition of mitomycin to vindesine plus cisplatin (80 mg/m2) in 126 previously untreated non-small cell lung cancer (NSCLC) patients. 124 patients were evaluable for toxicity and survival and 122 for response. No patient achieved complete response. The partial response rate (PR) in the vindesine plus cisplatin (VP) and mitomycin plus vindesine and cisplatin (MVP) groups were 23% (14/62) vs. 35% (21/60) (P = 0.13) with a median duration of response of 23 vs. 37 weeks (P = 0.071), respectively. Time to progression (TTP) and survival time (ST) were similar for both treatment arms [median TTP; 14 vs. 21 weeks (P = 0.10), median ST; 9.1 vs. 10.5 months (P = 0.94), respectively]. No difference in the frequency of side-effects was observed except that WHO grade 3 and 4 leukopenia was higher in the MVP group. In multivariate analysis, the significant predictors of survival were serum albumin, sex, performance status, lactate dehydrogenase and stage. In conclusion, the addition of mitomycin to the VP regimen appears to have limited value in advanced NSCLC.