An increase in the neutrophil-to-lymphocyte ratio during adjuvant chemotherapy indicates a poor prognosis in patients with stage II or III gastric cancer

Background The neutrophil-to-lymphocyte ratio (NLR) and the platelet-to-lymphocyte ratio (PLR) are associated with poor prognoses in patients with gastric cancer; however, few studies have focused on the dynamic changes in these ratios during the treatment of patients with gastric cancer. Here, we assessed the clinical utility of changes in these ratios as prognostic indicators in patients with stage II or III gastric cancer who received adjuvant chemotherapy. Methods We retrospectively reviewed 100 patients who received S-1 adjuvant chemotherapy at ≥70% of the relative dose intensity, and their NLRs and PLRs were evaluated at different times: prior to gastrectomy and upon commencement and termination of adjuvant chemotherapy. To assure the clinical utility of the changes in NLR and PLR as prognostic indicators, other clinical factors were assessed as well. Results Disease recurred in 35 patients as follows: lymph node metastasis (17 patients, 17.0%), peritoneal metastasis (12 patients, 12.0%), and hematogenous metastasis (6 patients, 6.0%); 24 patients died. An increase in the NLR during adjuvant chemotherapy with S-1 was identified as an independent indicator associated with overall survival (hazard ratio [HR] 6.736, 95% confidence interval [CI] 2.420–18.748; P < 0.001), and relapse-free survival (HR 5.309, 95% CI 2.585–10.901; P < 0.001). Conclusion An increase in the NLR during S-1 adjuvant chemotherapy may be a useful prognostic indicator in patients with stage II or III gastric cancer.