Preoperative neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio are correlated with tumor-node-metastasis stages in patients with non-small cell lung cancer

Background: The aim of this study is to explore the value of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) for predicting the tumor-node-metastasis (TNM) stages in non-small cell lung cancer (NSCLC) patients. Methods: This retrospective study included 205 NSCLC patients receiving surgical treatment. We used receiver operating curve analysis to confirm the optimal cutoff values of NLR and PLR. Results: The result showed that the thresholds for NLR and PLR were 1.8 and 103.59, respectively. NLR ( P = 0.037; relative risk (RR), 3.027; 95% confidence interval (CI): 1.608-8.581) and PLR ( P = 0.001; RR, 3.662; 95% CI: 1.342-9.992) were risks factors in predicting advanced TNM stages (Stage III/IV, all P < 0.05). In addition, NLR with T stage- and N stage-dependent increase may be a potential and independent predictive marker for T and N stage (all P < 0.05); the PLR was identified as a marker for T stage ( P = 0.028) but not for N stage. Furthermore, we investigated the combination of NLR and PLR (CNP). A risk stratification based on CNP index was carried out as follows: low risk (NLR <= 1.8 and PLR <= 103.59), intermediate risk (either NLR >1.8 or PLR > 103.59), and high risk (both NLR >1.8 and PLR >103.59). The probabilities for developing advanced TNM stage were 6.4% for low, 20.4% for intermediate, and 47.1% for high-risk group ( P < 0.001). Conclusion: The levels of preoperative NLR and PLR were capable of indicating advanced TNM stages. According to the CNP index, patients were divided into three risk groups with different significance.