Abstract: Objective This article retrospectively analyzed the efficacy,toxicity,survival and related factors affecting prognosis of patients with small cell lung cancer(SCLC)who had recurrence or progression after first-course chemoradiotherapy.Methods A total of 86 patients with recurrence or progression recurrence after SCLC chemotherapy and radiotherapy from January 2007 to December 2015 in Harbin Medical University Cancer Hospital were enrolled.Patients were divided into the re-treatment group to receive secondary treatment with radiotherapy combined with chemotherapy and two control groups to receive secondary treatment with radiotherapy alone or chemotherapy alone.The factors affecting the prognosis of SCLC re-treatment were analyzed.The short-term and long-term efficacy,overall survival and toxicity of three groups were compared.Results The median progression-free survival time of the re-treatment group,radiotherapy group,and chemotherapy alone group was 4 months(1~20 months),2 months(1~7 months)and 3 months(1~6 months).There was no statistical difference(P＞0.05).The median overall survival time was 25 months(3~135 months)in the re-treatment group and 8 months in the radiotherapy group(1-59 months)and 12 months(1~108)in the chemotherapy alone group,the difference was statistically significant(P＜0.05).The 1-,2-,and 3-year survival rates were 73.70%,52.10% and 47.40% in the re-treatment group;32.90%、21.90% and 21.90% in the radiotherapy group,and 45.40%,19.90% and 19.90% in the chemotherapy alone group.The long-term effect of the re-treatment group was better than that of the radiotherapy group and the chemotherapy alone group(P＜0.05).Conclusion Re-treatment of patients with SCLC who failed after receiving radiotherapy and chemotherapy for the first time can prolong the survival time of patients and improve the life quality of patients.If the patient's physical condition permits,the treatment should be selective radiotherapy and chemotherapy as well as tolerable toxicity or side effects.Among them,patients with no distant metastasis and recurrent radiotherapy dose ≥5 000 cGy had greater survival benefit.However,the late toxic and side effects,and complications of patients after re-treatment are still to be further observed.

Key words: Cancer, Small cell lung cancer, Recurrence, Routine radiotherapy, Chemotherapy