The prognostic effect of immunohistochemical staining ezrin, carbonic anhydrase ix and neuropilin-2 on metastatic renal cell carcinoma patients under tyrosine kinase inhibition

Introduction: The identification of prognostic factors in patients with renal cell carcinoma (RCC) represents an area of increasing interest. This study used a cohort of patients treated for RCC to provide information about biomarkers and prognosis. The purpose of this study was to evaluate prognostic factors in patients with RCC. Materials and Methods: The expression of several biomarkers were measured by immunohistochemistry (IHC) in 45 patients with advanced RCC treated with second-line vascular endothelial growth factor (VEGF) targeted tyrosine kinase inhibitors (TKIs) after failure of interferon-alpha between January 2007 and June 2012. Kaplan-Meier and log-rank analyses were employed on PFS and OS and multivariate Cox proportional hazard model analyzed clinical parameters for their prognostic relevance. Results: Age, ezrin and neuropilin-2 overexpression were statistically significant factors (P <0.05) for PFS in the univariate analysis. Ezrin and neuropilin-2 overexpression, hemoglobin and albumin were statistically signifiant factors (P <0.05) for OS in the univariate analysis. Multivariate analysis revealed that low expression of ezrin and neuropilin-2 were a favorable prognostic factor independent of PFS and OS. Median PFS was 4 versus 11 months in patients with overexpression neuropilin-2 versus low expression neuropilin-2 (p=0.033). The median OS was 13 months versus 26 months, in patients with overexpression neuropilin-2 versus low expression neuropilin-2, respectively (p=0.023). 104 Increased expression of ezrin was related to poor prognosis with VEGF targeted TKI treatment (PFS, 3 vs. 7 months p=0.012). Conclusion: Neuropilin-2 and ezrin in particular are useful prognostic factors in patients with advanced RCC.