The clinical use of neutrophil-to-lymphocyte ratio in bladder cancer patients: a systematic review and meta-analysis.

The aim of this study was to evaluate the evidence regarding the neutrophil-to-lymphocyte ratio (NLR) as a factor predictive of survival in bladder cancer patients. A search of PubMed and Embase for relevant studies between January 1, 1966 and November 10, 2016 was performed with the terms [NLR OR (neutrophil lymphocyte ratio)] AND [(bladder cancer) OR BCa OR NMIBC OR MIBC]. Inclusion required studies published in English containing bladder cancer patients and evaluating NLR as a predictive factor. Endpoints of NLR and survival data were extracted for pooled analysis. The pooled results showed that an elevated NLR was a predictor for poor overall survival (OS) [hazard ratio (HR) = 1.19, 95% confidence interval (CI) 1.07-1.31], cancer-specific survival (CSS) (HR = 1.40, 95% CI 1.17-1.69), recurrence-free survival (RFS) (HR = 1.58, 95% CI 1.24-2.03) and progression-free survival (PFS) (HR = 1.33, 95% CI 1.19-1.49) in patients with bladder cancer. Heterogeneity between studies was observed for OS, CSS and RFS, but not for PFS. Publication bias was detected for all these outcomes. Our results showed that elevated NLR might be valuable as a predictive factor of survival in bladder cancer patients.