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

Abstract

Accumulated evidence has suggested that there is a close association between preoperative neutrophil-to-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 15 950 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 cancer-specific 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, Madder cancer, prostate cancer and upper tract urothelial carcinoma.