Normalization of C-reactive protein levels following cytoreductive nephrectomy in patients with metastatic renal cell carcinoma treated with tyrosine kinase inhibitors is associated with improved overall survival.

INTRODUCTION AND OBJECTIVES: Pretreated C-reactive protein (CRP) has been suggested as one of the most important prognostic factors for metastatic renal cell carcinoma (mRCC). The aim of this study was to investigate the prognostic impact of the change in CRP level before and after cytoreductive nephrectomy (CN) in patients with mRCC treated with tyrosine kinase inhibitor.

MATERIALS AND METHODS: The CRP in 60 patients undergoing molecular targeted therapy for mRCC was measured before and after CN. The cutoff value of CRP was determined to be 0.5mg/dl.; thus, all patients were classified into lower CRP groups and higher ones according to their CRP before CN. The higher CRP group was further classified into 2 groups based on the kinetics after CN, "normalized CRP group" and "nonnormalized CRP group," respectively. The overall survival (OS) of these groups was compared.

RESULTS: The median of the observation period was 21.6 months. The OS of patients in the lower CRP, normalized CRP, and nonnormalized CRP groups were 28.6, 23.1, and 12.3 months, respectively (nonnormalized CRP group vs. others, P<0.0001). Multivariate analysis revealed that the postoperative CRP level (≥0.5mg/dl) (hazard ratio = 0.218; 95% CI: 0.091-0.522; P = 0.0006) was an independent predictive factor of OS.

CONCLUSION: The CRP level after CN can be a predictive factor for OS in patients with mRCC treated with tyrosine kinase inhibitor.