Recurrent or persistent small-cell carcinoma of the lung (SCCL) after chemotherapy (CT) alone has shown a poor response to conventional salvage radiotherapy (RT). Accelerated RT is judged more effective than conventional RT for rapidly growing tumors such as SCCL. The objectives of this study were: to determine the tolerability of accelerated RT; and to test the ability of accelerated RT plus CT to achieve local tumor control (LTC) of SCCL recurrent after CT. Patients whose localized tumor was not controlled were selected from Arm III of the Cancer and Leukemia Group B (CALGB) protocol 8083 (Proc. ASCO 2:230, 1984) as eligible for this study. The program of accelerated RT consisted of the delivery of 50.1 Gray (Gy) in 30 fractions over a period of 21 days to the chest. New chemotherapy different from the first began 2 weeks after the completion of RT and was repeated every 3 weeks for 18 months (M). Of 29 potentially eligible patients with locally recurrent SCCL after the first line CT alone from Arm III of the CALBG protocol 8083, 12 were enrolled initially in this study. The analysis of LTC included 11 patients excluding one patient who died 4 weeks after the start of RT from liver metastases. The LTC achieved was as follow: complete remission in 8/11 (72%) and partial remission in 3/11 patients. None of the patients was converted to CR by subsequent chemotherapy. Survival ranged from 2 to 20 M, with a median survival time of 6 M. Tolerance to the subsequent CT, normal tissue reaction to accelerated RT, and the theoretical advantage of accelerated RT over conventional RT for SCCL were evaluated.