Critical evaluation of the potential prognostic value of the pretreatment-derived neutrophil-lymphocyte ratio under consideration of C-reactive protein levels in clear cell renal cell carcinoma

Background: We investigated the prognostic value of the pretreatment-derived neutrophil lymphocyte ratio (dNLR) and original NLR in relation to the commonly used inflammation marker C-reactive protein (CRP) in a large cohort of patients with clear cell renal cell carcinoma (RCC). Methods: Clinicopathological data from 587 consecutive non-metastatic clear cell RCC patients, operated between 2000 and 2010 at a single tertiary academic center, were evaluated retrospectively. Patients were categorised according to a cutoff value derived from receiver operating curve analysis. Overall (OS), cancer-specific (CSS) as well as metastasis-free survival (MFS) were assessed using the Kaplan Meier method and multivariate Cox proportional models were applied. Spearman's rank correlation coefficient tested the association between dNLR and other markers of the systemic inflammatory response. Results: The significant correlation between pretreatment NLR and dNLR was strong (p = 0.84), whereas between dNLR and CRP it was weak (p = 0.18). In multivariate analyses, dNLR achieved independent predictor status regarding CSS (P=0.037) and MFS (P=0.041), whereas CRP was confirmed as independent predictor of OS (P= 0.010), CSS (P=0.039) and MFS (P=0.005), respectively. The NLR failed to reach independent predictor status regarding OS, CSS and MFS when CRP was included into the multivariate model. Conclusions: In the cohort studied, an elevated (10.0) pretreatment CRP level and elevated dNLR (>2) were robust independent predictors of CSS and MFS. Our data suggest that CRP might be superior to both NLR and dNLR.