Abstract: ［Abstract］ Objective〖HTSS〗〓To investigate the relationship between neutrophil lymphocyte ratio(NLR) and prognosis of patients with small cell lung cancer at first visit.
〖HTH〗〖WTHZ〗Methods〖HTSS〗〓The clinical data of 162 patients with small cell lung cancer who were diagnosed and untreated were collected. Using SPSS 22.0 software, we determine the NLR boundary value by using the ROC curve. According to the boundary value, the selected patients were divided into 2 groups, and through the KaplanMeier drawing method of progression free survival(PFS) and overall survival(OS) survival curve, non parametric test was carried out with Log Rank, respectively. The clinical features of high and low NLR group, patients in the NLR group and the influence on the prognosis of small cell lung cancer were observed. COX regression model was applied for multivariate survival analysis. Comprehensive evaluation of influence of NLR on small cell lung cancer prognosis was made. 
〖HTH〗〖WTHZ〗Results〖HTSS〗〓The median PFS and OS in the high NLR group were 6 months and 10.7 months respectively, while those in the low NLR group were 7.5 months and 14.3 months. In univariate analysis, risk factors for PFS: NLR, tumor stage, radiotherapy,chemotherapy, suggesting that the PFS of the patient with low NLR group , limited period, radiotherapy and chemotherapy was longer. On the contrary, it is short. Risk factors for OS: NLR, age, gender, tumor stage, radiotherapy,chemotherapy, suggesting that the OS of the patient with low NLR group,youger than 60 age,female,limited period, radiotherapy and chemotherapy was longer. On the contrary, it is short. In multivariate analysis, the curative effect of chemotherapy was an independent risk factor of small cell lung cancer PFS. Age, stage, radiotherapy,chemotherapy and NLR were the independent risk factors of prognosis in patients with small cell lung cancer OS.
〖HTH〗〖WTHZ〗Conclusion〖HTSS〗〓NLR is valuable in assessing the prognosis of patients with primary small cell lung cancer.

Key words: small cell lung cancer, granulocytes； lymphocytes； prognosis