Abstract: ［Abstract］ Objective〖HTSS〗〓To evaluate the correlation of pretreament neutrophil/lymphocyte ratio(NLR) with the prognosis of patients with small cell lung cancer.
〖HTH〗〖WTHZ〗Methods〖HTSS〗〓The clinical data of 75 small cell lung cancer with pathologically diagnose were retrospectively analyzed. Routine peripheral blood test results were used to calculate the NLR. The patients were divided into two groups(high NLR group and low NLR group) with the median value of NLR. The clinical features of high and low NLR group were compared. The differences of overall survival(OS) and progressivefree survival(PFS) were compared in the two groups. The factors affecting PFS and OS in SCLC patients were analyzed.
〖HTH〗〖WTHZ〗Results〖HTSS〗〓The proportion of the high NLR group in extensive stages was higher than that of the low NLR group, and the difference was statistically significant(P＜005). The median PFS of the high NLR group and the low NLR group was 5.73 months vs 8.50 months, respectively, and the difference was statistically significant(P＜005). The median OS in the high NLR group and the low NLR group was 10.57 months and 15.10 months, respectively, with statistically significant differences(P＜005). The Cox regression analysis showed that clinical stage and NLR level were prognostic factors.
〖HTH〗〖WTHZ〗Conclusion〖HTSS〗〓High NLR often indicates poor prognosis, and it is an important prognostic factor and plays an important role in prognostic evaluation of SCLC patients.

Key words: small cell lung carcinoma, neutrophil/lymphocyte ratio, prognosis