AbstractBackgroundDevelopment or progression of inflammation in neoplastic diseases is known to be part of the disease. Lymphocyte to C‐reactive protein ratio (LCR) is a new indicator showing the inflammatory state. The aim of this study is to show the clinical importance of the relationship between the preoperative LCR and the prognosis of patients with gastric cancer.Methods and PatientsWe evaluated gastric cancer patients, who underwent surgery between 2010 and 2015. LCR and neutrophil‐to‐lymphocyte ratio (NLR) were calculated from pre‐treatment of complete blood counts. Both ratios were compared to the perioperative outcomes and median survival times. Association between LCR and postoperative tumour stage was studied by using multivariate analysis with other clinicopathological variables.ResultsA total of 123 patients were included. The mean age of the patients was 65.36 ± 10.08. Preoperative low LCR value was associated with advanced tumour stage, adjacent organ invasion, lymph node metastasis and postoperative early complications. The receiver operating characteristic analysis results showed that LCR and NLR parameters were significant (CI 0.718–0.886; 95%); P < 0.001, CI 0.534–0.732; 95%). Cut‐off value being 193, the mean survival of patients who had LCR values of overcut‐off value was found to be significantly higher compared with the patients with lower LCR values (P < 0.001).ConclusionLCR, a simple calculated ratio of values obtained from easy and widely available serum indicators could be an effective prognostic marker with gastric cancer.