A novel preoperative inflammatory marker prognostic score in patients with localized and metastatic renal cell carcinoma

Objective: Several inflammatory markers have been studied as potential biomarkers in renal cell carcinoma (RCC), however few reports have analyzed their prognostic value in aggregate and in non-clear cell histologies. We hypothesize that a combination of specific inflammatory markers into an RCC Inflammatory Score (RISK) could serve as a rigorous prognostic indicator of overall survival (OS) in patients with clear cell and non-clear cell RCC.

Methods: Combination of preoperative C-reactive protein (CRP), albumin, erythrocyte sedimentation rate (ESR), corrected calcium, and aspartate transaminase to alanine transaminase (AST/ALT) ratio was used to develop RISK. RISK was developed using grid-search methodology, receiver-operating-characteristic (ROC) analysis, and sensitivity-specificity trade-off analysis. Prognostic value of RISK was analyzed using the Kaplan-Meier method and Cox proportional regression models. Predictive accuracy was compared with RISK to Size, Size, Grade, and Necrosis (SSIGN) score, University of California-LOS Angeles (UCLA) Integrated Staging System (UISS), and Leibovich Prognosis Score (LPS).

Results: Among 391 RCC patients treated with nephrectomy, area under the curve (AUC) for RISK was 0.783, which was comparable to SSIGN (AUC 0.776, p = 0.82) and UISS (AUC 0.809, p = 0.317). Among patients with localized disease, AUC for RISK and LPS was 0.742 and 0.706, respectively (p = 0.456). On multivariate analysis, we observed a step-wise statistically significant inverse relationship between increasing RISK group and OS (all p < 0.001).

Conclusion: RISK is an independent and significant predictor of OS for patients treated with nephrectomy for clear cell and non-clear cell RCC, with accuracy comparable to other histopathological prognostic tools.