Between June 1980 and December 1983, 111 patients with inoperable epidermoid bronchogenic carcinoma (limited disease) were entered into a randomized trial comparing radiotherapy alone versus radiotherapy and combination chemotherapy with cyclophosphamide, Adriamycin (doxorubicin), methotrexate, and procarbazine. Thirty-five of 62 (56.4%) patients treated with 4500 rad in 15 fractions in 3 weeks and 19 of 49 (38.8%) patients treated with the same radiation treatment and chemotherapy had an objective response. The difference in response rate was not significant (P = 0.900). Median time to progression was 5.9 and 7.02 months, respectively, for the radiation treatment and the combined treatment. Median survival was 11.74 and 10.03 months, respectively, without statistically significant differences between the two groups of patients. The toxicity was acceptable and no treatment-related death occurred in either treatment schedule. In this study no significant superiority of combined radiotherapy and chemotherapy treatment over radiation therapy alone was evidenced. Whether different chemotherapy regimens may prove more effective in this context should be clarified by further studies.