Prognostic Significance of C-reactive Protein in Patients With Non-metastatic Papillary Renal Cell Carcinoma: Results from the INternational Marker Consortium for Renal Cancer (INMARC) Cohort.

Abstract

C-reactive protein is a useful biomarker for screening renal cell carcinoma (RCC); however, its significance in papillary RCC is unclear. We assessed the prognostic effect of serum C-reactive protein levels in patients with surgically treated non-metastatic papillary RCC. We established an international multi-institutional database (the INternational Marker Consortium for Renal Cancer) of 3799 patients with surgically treated RCC. Among these, data of 400 patients with non-metastatic papillary RCC were analyzed. An elevated pretreatment serum C-reactive protein level was defined as > 10 mg/L. Associations of clinical covariates with recurrence-free survival were investigated. Among the patients, 174 were African Americans, 155 were European-Americans, 50 were Asians, and 21 were of other races. Pathological T stages were 1, 2, 3, and 4 in 313, 46, 32, and 3 patients, respectively. The median pretreatment C-reactive protein level was 1.0 mg/L; 48 patients exhibited an elevated C-reactive protein level. During follow-up (median 18 months), 30 patients presented recurrence. The 1-, 3-, and 5-year recurrence-free rates were 95%, 91%, and 87%, respectively. Multivariate analysis revealed a significant association of the elevated pretreatment C-reactive protein level with poor recurrence-free survival (hazard ratio 2.47, 95% confidence interval 1.03-5.48; P=.043). The 5-year recurrence-free survival was significantly worse for patients with elevated C-reactive protein levels (67% vs. 90%; P=.001). C-reactive protein is a significant prognostic factor for patients with non-metastatic papillary RCC and can serve as a useful adjunct biomarker for screening patients with a high risk of recurrence.