Independent risk factors for lymph node metastasis in 2623 patients with Non-Small cell lung cancer

Purpose: this study attempts to identify the independent risk factors that can predict lymph node metastasis for the patients with non-small cell lung cancer (NSCLC), and guide doctor adoption of individualized treatment for such patients. Materials and methods: This study was approved by the Hospital's Ethics Committee and all patients had signed informed consent forms. We retrospectively reviewed NSCLC patients who had undergone surgical resection from December 2008 to December 2013. The statistical significance of evaluation variables and lymph node metastasis was determined with Pearson's Chi-square test. The risk factors of lymph node metastasis were determined through univariate and multivariate logistic regression analysis. And for the age and tumor diameter factors, optimal cutoff points were determined with a receiver operating characteristic analysis. Results: In the present study, a total of 2623 patients were included in the study, and 779 patients with lymph node metastasis. Three independent risk factors were identified: age, tumor diameter and Ki-67 index. We found that <65 years of age (Adjusted-OR:1.921), >=.2.85 cm of tumor diameter (Adjusted-OR:3.141), and 5% similar to 25% in Ki-67 group (Adjusted-OR:2.137), >= 25% (Adjusted-OR:3.341) were significant. Also we found that 307 patients with lymph node metastasis and the lymph node metastasis rate was 51.0%, when the age<65 years, Ki-67 index >= 25%, and the tumor diameter >= 2.85 cm. On the contrary, there were only 2 patients with lymph node metastasis, and the rate of lymph node metastasis was 5.1%. Conclusion: Identifying three independent risk factors that predict lymph node metastasis in non-small cell patients, Among NSCLC patients in whom all three predictors were identified, and over a half of the patients showed lymph node metastasis.