Preoperative Elevation of C-Reactive Protein Is a Predictor for Adverse Oncologic Survival Outcomes for Renal Cell Carcinoma: Analysis from the International Marker Consortium Renal Cancer (INMARC)

Background: We sought to analyze the usefulness of pretreatment C-reactive protein (CRP) as a predictor of survival and oncological outcomes in patients with renal cell carcinoma (RCC). Methods: Retrospective international analysis of patients with RCC with pretreatment CRP values from 2006 to 2017. A CRP of more than >5 mg/L was deemed elevated. The cohort was subdivided into 2 groups for analysis (normal CRP ≤5 mg/L; elevated CRP >5). Primary outcome was overall survival (OS) and secondary outcome was recurrence-free survival (RFS). Kaplan–Meier analyses (KMA) and multivariable analyses (MVA) were used to delineate survival outcomes and their predictors. Results: We analyzed 2445 patients (1641 male/804 female; normal CRP 1056/elevated CRP 1389; mean follow-up 36 months). Patients with elevated CRP had a higher incidence of hypertension (P = .001), higher body mass index (P < .001), and larger tumor size (6.0 cm vs 3.9 cm; P < .001). MVA for RFS demonstrated elevated CRP (hazard ratio [HR], 1.85; P = .005), tumor size (HR, 1.1; P < .001), and high tumor grade (HR, 3.1; P < .001) to be independent risk factors. For normal vs elevated CRP, KMA for RFS of stages 1–4 RCC revealed a 5-year RFS of 93% vs 88% (P = .001), 95% vs 83% (P = .163), 84% vs 62% (P = .001), and 58% vs 60% (P = .513), respectively. KMA MA KMA for OS of stages 1–4 RCC revealed a 5-year OS of 98% vs 81% (P = .001), 94% vs 80% (P = .103), 94% vs 65% (P = .001), and 99% vs 38% (P < .001), respectively. Conclusions: Pretreatment CRP was an independent predictor of RFS and OS in an international multicenter cohort of patients with RCC.