The present series consisted of 55 patients with non-small cell lung cancer in stage III who underwent radiotherapy from 1986-1989. They were divided into two groups: 35 patients with combined concurrent bronchial artery infusion (BAI) of CDDP (50 mg) and unevenly fractionated radiotherapy (combined group) and 20 with evenly fractionated irradiation (radiation group). The combined therapy was expected to achieve higher local control of disease. The rationale for the combined regime was based on the effects of CDDP, which causes cytostasis following intra-arterial infusion, and increased radiosensitivity from unevenly fractionated irradiation just after BAI. The radiotherapy group was considered a control in this study. The results of the combined group were limited to no CR, PR in 33 patients and NC in two with a period of 30 +/- 13 days for 50% reduction of tumor, superior to the radiation group. There was no difference between the two groups in the rate of local recurrence (combined group: 63%). The combined group showed 28 months of MST in cause-specific survival, a significant difference. Survival rates were 71% at one year, 27% at three years, and 15% at five years, including three survivors without recurrence. Stage III a patients in the combined group showed a better outcome than stage III b patients in the same group, and stage III a patients in the radiation group. Although radiation pneumonitis as a fatal side effect was noted in one patient of the combined group, the combined therapy presented here seemed to improve the prognosis of locally advanced lung cancer if properly indicated.