Value of Preoperative Neutrophil-to-Lymphocyte Ratio in Predicting Prognosis of Surgically Resectable Urinary Cancers: Systematic Review and Meta-Analysis

Objective Accumulated evidence has suggested that there is a close association between preoperative neutrophilto-lymphocyte ratio(NLR)and prognosis of various malignant tumors.However,the relationship between NLR and surgically resectable urinary cancers remains contradictory.Therefore,we performed this systematic review and meta-analysis to explore whether preoperative NLR could predict the prognosis of surgically resectable urinary cancers.Methods After searching the Embase,PubMed/MEDLINE and Cochrane databases and screening the articles,we finally included 25 studies involving 15950 patients.Hazard ratios(HRs)and their 95%confidence intervals(CIs)were extracted to assess the association between preoperative NLR and the overall survival(OS)and cancerspecific survival(CSS)of surgically resectable urinary cancers.Results The pooled results revealed that an elevated preoperative NLR could predict a worse OS(HR=1.40,95%CI:1.26–1.54,P<0.001)and CSS(HR=1.43,95%CI:1.27–1.59,P<0.001)in urinary cancers.In addition,our analyses also suggested that high preoperative NLR was associated with worse prognosis in renal cell carcinoma(OS:HR=2.06,95%CI:1.54–2.76,P=0.131;CSS:HR=2.46,95%CI:1.46–4.16,P=0.178),upper tract urothelial carcinoma(OS:HR=1.91,95%CI:1.50–2.42,P=0.616;CSS:HR=1.84,95%CI:1.41–2.39,P=0.001),bladder cancer(OS:HR=1.09,95%CI:1.02–1.17,P<0.001;CSS:HR=1.05,95%CI:1.01–1.09,P=0.163)and prostate cancer(OS:HR=1.69,95%CI:1.19–2.41,P=0.714).Regardless of the participants’race or the cutoff value of the preoperative NLR,the results remained valid.Conclusion Elevated preoperative NLR could predict a worse prognosis in surgically resectable urinary cancers,namely,renal cell carcinoma,bladder cancer,prostate cancer and upper tract urothelial carcinoma.