Correlational Research Of Sequential Chemo-radiotherapy For Limited-stage Small Cell Lung Cancer

Objective: To analyze the effect of sequential chemo-radiotherapy in patients with limited-stage small-cell lung cancer(LS-SCLC).To study the optimal timing of radiotherapy and prognostic factors with sequential chemo-radiotherapy for LS-SCLC.Methods: The clinical records of 133 patients with LS-SCLC treated in Cancer Hospital of China Medical University between October 2012 and August 2015 were analyzed retrospectively in this study.All patients were divided into early and late groups based on immediate radiotherapy after one to two cycles of induction chemotherapy.Chi-square test was used for correlation analysis.Kaplan-Meier method was used for survival analysis,and Log-rank test and Cox regression were used for univariate and multivariate analyses of prognostic factors.Results: The median overall survival(OS)was 28.7 months,and the 1-year,2-year and 3-year OS rate were 88.0%,57.1% and 34.1%,respectively.The median progression-free survival(PFS)was 18.5 months,and the 1-year,2-year and 3-year PFS rate were 65.0%,44.3% and 38.3% respectively.There were 20 cases(15.0%)in the early radiotherapy group and 113 cases(85.0%)in the late radiotherapy group.The median OS of the two groups was 28.7 and 27.5 months,respectively,and the difference was not statistically significant(P=0.555),but the median PFS of the early radiotherapy group was significantly longer than that of the late radiotherapy group,and the difference was statistically significant(P=0.005).Grouping analysis showed that in the late radiotherapy group,women,patients receiving effective initial chemotherapy and preventive prophylactic cranial irradiation(PCI)had better prognosis,and the difference was statistically significant(P<0.05).The univariate analysis showed that gender(P=0.015),response of induction chemotherapy(P=0.021),PCI(P=0.012)were related to overall survival(OS)time;gender(P=0.029)and timing of radiotherapy(P=0.005)were related to progression-free survival(PFS).The multivariate analysis showed that gender,effective induction chemotherapy and undergoing prophylactic cranial irradiation(PCI)were independent factors affecting the OS(P<0.05 for all).Gender and early radiotherapy were independent factors affecting the PFS,the differences were statistically significant(P<0.05 for all).Conclusions: 1.Sequential chemo-radiotherapy can effectively improve the prognosis of patients with LS-SCLC.2.The best timing of thoracic radiotherapy was immediate radiotherapy after one to two cycles of induction chemotherapy.3.Among the patients who started radiotherapy in the late group,female,received effective initial chemotherapy and received PCI had better prognosis.4.These factors,such as gender,efficacy of initial chemotherapy and treatment with PCI were independent factors affecting OS;gender,timing of thoracic radiotherapy were independent factors affecting PFS in patients with LS-SCLC.