A phase II study was conducted with three different combinations of cyclophosphamide, Oncovin (vincristine), methyl-CCNU, and bleomycin (COMB) in 106 patients with advanced bronchogenic carcinoma of all histologies. The response rates were 27.3% for COMB I (six of 22 patients), 18.2% for COMB II (eight of 44 patients), and 7.5% for vincristine, methyl-CCNU, and bleomycin (three of 40 patients). Complete responses were seen only in the small cell carcinoma group. Duration of remission and overall survival were of significance for the small cell group, whereas survival for the other histologic types comparing responders to nonresponders was of no statistical significance. Toxicity was significant and included nausea and vomiting, neuropathy, and myelosuppression. These drug combinations were disappointing and only in small cell carcinoma was meaningful antitumor activity seen.