The prognostic significance of the neutrophil-to-lymphocyte ratio in esophageal cancer patients undergoing chemoradiotherapy: a meta-analysis

Objective: Recent research increasingly highlights the association between inflammation and esophageal cancer, with radiotherapy and chemotherapy being crucial in treatment of advanced stages. This meta-analysis aims to investigate the association between the neutrophil-to-lymphocyte ratio (NLR) and the prognosis of esophageal cancer patients undergoing chemoradiotherapy. Methods: A systematic search of PubMed, Embase, Web of Science, and Cochrane was performed. Data were extracted and analyzed using STATA 12.0 to consolidate effect sizes, test heterogeneity, and assess sensitivity for publication bias and heterogeneity sources. Results: Elevated NLR was significantly associated with shorter overall survival (OS) (HR: 1.515, 95% CI: 1.278-1.795) and progression-free survival (PFS) (HR: 1.419, 95% CI: 1.003-2.009). This association was particularly strong in male patients (HR: 1.755, 95% CI: 1.373-2.245) and those with cervical esophageal cancer (HR: 1.876, 95% CI: 1.280-2.751). Sensitivity analysis confirmed the robustness of these findings, and no significant publication bias was detected. Heterogeneity in the OS group may be attributed to variations in treatment (P=0.02) and data analysis methods (P=0.007). Conclusion: NLR is a readily available, cost-effective, and reliable prognostic marker for esophageal cancer patients undergoing chemoradiotherapy, especially in male patients with cervical esophageal cancer.