PURPOSE: Several recent studies have reported on the clinical importance and prognostic significance of neutrophil-to-lymphocyte ratio (NLR) in gastric cancer. The objective of this study was to identify the subgroups of patients with gastric cancer for which the preoperative NLR was prognostically significant.METHODS: Data from 870 patients who were among those who had undergone surgery for gastric cancer between August 2005 and December 2013 were evaluated. Receiver operating characteristic curve analysis was used to determine the cut-off value for NLR. The patients were classified into high-NLR (NLR≥1.7) and low-NLR (NLR<1.7) groups, and survival analysis of subgroups of gastric cancer patients was performed.RESULTS: Univariate analysis identified age, gender, tumor location, tumor histology, tumor, node, metastasis (TNM) stage, and NLR as significant prognostic factors. Multivariate analysis identified age, TNM stage, and NLR as significant prognostic factors. In subgroup analysis, NLR was a significant prognostic factor except group of TNM stage I, II with age younger than 70 years.CONCLUSION: Except group of TNM stage I, II with age younger than 70 years, careful postoperative follow-up is warranted for those patients with elevated NLR.