Prognostic Markers for Refined Stratification of IMDC Intermediate-Risk Metastatic Clear Cell Renal Cell Carcinoma Treated with First-Line Tyrosine Kinase Inhibitor Therapy

Abstract

Background: Patients in the International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) intermediate-risk group have heterogeneous prognoses and thus may benefit from improved risk stratification. Objective: The aim of this study was to analyze inflammatory parameters such as C-reactive protein (CRP) and neutrophil-to-lymphocyte ratio (NLR) as prognostic markers for IMDC intermediate-risk patients. Methods: Patients with metastatic clear cell renal cell carcinoma (n = 71) with IMDC intermediate risk who received tyrosine kinase inhibitors as first-line therapy were included in this retrospective study. Multivariate Cox regression analyses were performed to identify prognostic factors for overall survival (OS). Results: As first-line systemic therapy, 46 (65%), 19 (27%), and 6 (8%) patients received sunitinib, sorafenib, and pazopanib, respectively. An IMDC prognostic score of 1 and 2 were observed in 34 (48%) and 37 (52%) patients, respectively. Mean CRP level was 1.06 mg/dL, and mean NLR was 3.0. Multivariate Cox regression revealed several factors significantly associated with poor OS, including NLR ≥ 3 (vs NLR < 3; hazard ratio [HR] 2.57; p = 0.0228), CRP level ≥ 1 mg/dL (vs CRP < 1 mg/dL; HR 2.89; p = 0.0279), and two or more metastatic organs (vs one organ; HR 3.77; p = 0.0008). Using these risk factors, patients were stratified into the following three risk categories: F0 (no prognostic factors; n = 20), in which the median OS (mOS) was not achieved; F1 (1 prognostic factor; n = 31), in which the mOS was 31 months; and F2–3 (2 or 3 prognostic factors; n = 20) in which the mOS was 13 months (log-rank p < 0.0001). Conclusion: CRP, NLR, and the number of metastatic organs were independent prognostic factors in IMDC intermediate-risk patients.