Meta-analysis of the efficacy of the pretreatment neutrophil-to-lymphocyte ratio as a predictor of prognosis in renal carcinoma patients receiving tyrosine kinase inhibitors

The data on the impact of the neutrophil-to-lymphocyte ratio (NLR) in metastatic renal cell carcinoma (mRCC) patients receiving tyrosine kinase inhibitors (TKIs) are inconsistent. We therefore performed a meta-analysis to assess the prognostic value of pretreatment NLR in patients treated with TKIs for mRCC. We searched the Embase, Medline, PubMed, Cochrane and ISI Web of Knowledge to identify clinical studies that had evaluated the association between the pretreatment NLR and prognosis in mRCC patients. Prognostic outcomes included overall survival (OS) and progression-free survival (PFS). Nine studies encompassing a total of 1091 participants were included. We found that a high NLR was an effective prognostic marker of both OS (pooled HR: 1.93, 95% CI: 1.35-2.77; P = 0.0003) and PFS (pooled HR: 2.12, 95% CI: 1.42-3.17; P = 0.0002). Subgroup analysis revealed that studies reporting a NLR ≥ 3 showed a more significant effect of NLR on both OS (pooled HR: 2.50, 95% CI: 1.99-3.14; P = 0.0003) and PFS (pooled HR: 2.17, 95% CI: 1.26-3.75). This meta-analysis suggests that high pretreatment NLR is associated with a poor prognosis in mRCC patients receiving TKI treatment.