Fifty patients with small cell lung cancer were treated by radiotherapy mainly with maintenance chemotherapy. Relative survival for all cases combined was 34.6% for one year, 5.9% for three years, and 6.6% for five years; in the curative irradiation group, the corresponding figures were 72.2%, 12.5% and 13.6%. The cause of death in the palliative group was local lesion in 32% and multiple metastases in 43%. But in the curative irradiation group, it was local lesion in 22% and multiple metastases in 56%. Long-term survivors more than two years were all in the curative irradiation group, of the intermediate cell type and almost all had received over 50 Gy total dose, over 80 for TDF, within a two-month treatment period.