Prognostic and Clinicopathologic Significance of Neutrophil-to-Lymphocyte Ratio in Esophageal Cancer: An Update Meta-Analysis

Background: Esophageal cancer is one of the most common cancers with significant morbidity and mortality. It is important to predict the prognosis of patients. The purpose of this study was to comprehensively assess the prognostic and clinicopathologic significance of NLR in patients with esophageal cancer. Methods: A systematic literature search was performed using PubMed, Cochrane Library, Embase, Web of Science, MEDLINE, and CNKI. This meta-analysis was conducted in accordance with PRISMA guidelines. Hazard ratio (HR) with 95% confidence interval (CI) was used as the effect estimation to evaluate the prognostic role of NLR. Odds ratio (OR) was used to evaluate the relation between NLR and clinicopathologic characteristics. Results: A total of 8431 patients from 32 studies were included in this meta-analysis. The pooled results showed that elevated NLR might predict poor prognosis: The factors considered included overall survival (OS) (HR, 1.57; 95% CI, 1.40-1.75; P < .001), cancer-specific survival (CSS) (HR, 1.28; 95% CI, 1.09-1.49; P < .001), progression-free survival (PFS) (HR, 1.45; 95% CI, 1.29-1.72; P < .001), and disease-free survival (DFS) (HR,1.58; 95% CI, 1.27-1.97; P < .001). High NLR was also associated with tumor differentiation, tumor length, tumor invasion depth, lymph node metastasis, and clinical stage. No significant association was observed between NLR and metastasis stage (OR, 1.69; 95% CI, 0.98-2.98; P = .058). Conclusions: The results of this meta-analysis suggest that elevated NLR value might predict poor prognosis (OS, CSS, PFS, and DFS), according to abnormal clinicopathologic parameters.