From 1984 through 1986, 205 patients with non-small cell lung cancer were entered into a group-wide trial of the Swiss Group for Clinical Cancer Research (SAKK). This trial evaluated the combination of mitomycin (8 mg/m2 intravenously [IV] on day 1), vindesine (3 mg/m2 IV on days 1 and 8), and cisplatin (60 mg/m2 IV on day 1) with forced diuresis, repeated every 4 weeks (MiViP regimen). One hundred eighty-three patients were evaluable. Six complete and 69 partial responses were documented for an overall response rate of 41% (95% confidence interval, 34% to 50%). In the multivariate analysis the strongest predictors for response were the participating institution and the number of initially involved organ sites. The estimated median time to progression for patients with a complete response, partial response, or stable disease was 155 days (estimated inter-quartile range, 99 to 258 days). In the multivariate analysis the time to progression was significantly associated with the number of involved organ sites (P = 0.041). The estimated median survival time for the 183 evaluable patients was 239 days (estimated inter-quartile range, 137 to 436 days). In univariate and multivariate analyses performance status, number of involved organ sites, pretreatment status with radiation therapy, and participating institution were all significantly associated with survival. The principal toxicities were myelosuppression and nausea and vomiting with 16% of the patients refusing further treatment after a median of four cycles of chemotherapy. In conclusion, the MiViP regimen was an active combination chemotherapy in patients with non-small cell lung cancer in a large trial performed by the SAKK. The prognostic value of the participating institution and the number of organ sites involved by metastatic deposits in non-small cell lung cancer needs further investigation.