Prognostic Role of Neutrophil-to-Lymphocyte Ratio in Prostate Cancer: A Systematic Review and Meta-analysis.

Inflammation is increasingly reported to be associated with the prognosis of patients with cancers. And the prognostic role of neutrophil-to-lymphocyte ratio (NLR) in patients with prostate cancer (PCa) remains inconsistent. Therefore, we conducted this systematic review and meta-analysis to obtain a more reliable assessment of prognostic significance of NLR in PCa.A comprehensive literature research regarding the association of NLR and prognosis of PCa was performed through PubMed, Embase, Cochrane Central, and Web of Science. The hazard ratios (HRs) and its 95% confidence intervals (CIs) for overall survival (OS), progression-free survival, or recurrence-free survival were extracted and pooled using fix-effects model or random-effects model.A total of 14 studies that met our criterion were included in this meta-analysis. Our pooled results demonstrated that elevated NLR was not significantly associated with the poor OS (HR = 1.45; 95% CI 0.77-2.71; P = 0.248) or recurrence-free survival (HR = 1.34; 95% CI 0.89-2.02; P = 0.155) of patients with localized PCa. Although elevated NLR predicted poorer OS (HR = 1.57; 95% CI 1.41-1.74; P < 0.001) and progression-free survival (HR = 1.97; 95% CI 1.28-3.04; P = 0.002) of patients with metastatic castration resistant prostate cancer (mCRPC).Elevated NLR is a strong indicator of poorer prognosis of patients with mCRPC, whereas the NLR is not significantly associated with prognosis of patients with localized PCa. Therefore, NLR could be used in patients with mCRPC for risk stratification and decision making of individual treatment.