Prognostic significance of neutrophil-to-lymphocyte ratio in rectal cancer: a meta-analysis

Background: Inflammatory responses play decisive roles in tumor development, immune surveillance, and responses to therapy. High neutrophil-to-lymphocyte ratio (NLR), as an inflammation index, has been reported to be a predictor for poor prognosis of various cancers. The purpose of this meta-analysis was to evaluate the prognostic value of NLR in patients with rectal cancer. Methods: A comprehensive search of the literature was conducted through PubMed and EMBASE. Pooled hazard ratio (HR) with 95% confidence interval (CI) was used to evaluate the association between NLR and three outcomes: overall survival, disease-free survival, and recurrence-free survival. Results: Seven cohorts involving 959 patients were included in this meta-analysis. Our pooled results demonstrated that elevated NLR was associated with poor overall survival (HR: 13.41, 95% CI: 4.90-36.72), disease-free survival (HR: 4.37, 95% CI: 2.33-8.19), and recurrence-free survival (HR: 3.64, 95% CI: 1.88-7.05). Conclusion: An elevated NLR is a valuable and easily available prognostic marker for rectal cancer. It is associated with unfavorable overall survival, disease-free survival, and recurrence-free survival. NLR could be a useful candidate factor for making treatment decisions for individual patients with rectal cancer.