Prognostic value of lymphocyte-to-monocyte ratio previously determined to surgery in patients with non-metastatic renal cell carcinoma: A systematic review and a prisma-compliant meta-analysis

BACKGROUND: The prognostic value of pretreatment lymphocyte to monocyte ratio in patients with renal cell carcinoma and, especially, in non-metastatic patients remains controversial. METHODS: We conducted a PRISMA-compliant meta-analysis to systematically assess the prognostic value of LMR in patients with non-metastatic RCC. Overall survival, cancer-specific survival, and disease-free survival were analyzed. Pooled hazard ratios and 95% confidence intervals were calculated. RESULTS: Seven studies comprising 4666 patients were included in the analysis. Unlike those observed in a previous meta-analysis, a lower lymphocyte to monocyte ratio was associated with poorer cancer-specific survival (fix-effect model, hazard ratio 3.04, 95% confidence intervals 2.05–4.51, P < .05). Heterogeneity Chi-squared value Q exp = 0. (P = .82) (I(2) = 0%). However, the association between a low lymphocyte to monocyte ratio and overall survival or disease-free survival did not obtain significance. CONCLUSION: A lower lymphocyte to monocyte ratio implied poor cancer-specific survival in patients with non-metastatic renal cell carcinoma. Prospective studies are required to confirm our findings. REGISTRATION NUMBER: ClinicalTrials.gov (identifier: NCT04213664)