Clinical prognostic factors associated with outcome in renal cell cancer (RCC) patients with prior tyrosine kinase inhibitors or immunotherapy treated with everolimus.

Abstract

e15544 Background: Everolimus was approved for treating RCC patients who failed sunitinib or sorafenib by the Food and Drug Administration in 2009. We sought to develop a predictive clinical model predicting benefit for patients treated with everolimus as 2nd- or 3rd-line therapy for metastatic RCC. Methods: The study included 66 patients with RCC who failed immunotherapy or tyrosine kinase inhibitors to identify risk factors for progression-free survival (PFS) and overall survival (OS). Forty-one patients were updated with outcomes from the original phase II study (Amato 2009 Cancer) and an additional 25 patients were added from the expansion study. Kaplan-Meier method was used to calculate PFS and OS. Univariate and multivariate analyses were constructed using COX Proportional Hazard model and step-wise procedure. The model was validated by measuring the overall concordance index using the rms R package. Results: For the entire population, median PFS was 5.9 months (range, 0.4-34.5), and median OS was 16.1 months (range, 1.3-39.5). The univariate analysis revealed 5 factors associated with PFS and 9 factors associated with OS. From the multivariate analysis, 3 variables were kept in the final PFS model (LDH>203, no lung metastases, lymphocytes <25). Patients were assigned to 1 of 2 risk groups: ≤1 factor (favorable risk, median PFS 9.7 months) or ≥2 factors (poor risk, median PFS 2.8 months). Four variables were kept in the final OS model (lymphocytes <25, LDH >203, presence of bone metastasis, platelets ≥300). Patients were assigned to 1 of 3 groups: ≤1 factor (favorable risk, median OS 29.6 months), 2 factors (intermediate risk, median OS 14.3 months), or ≥3 factors (poor risk, median OS 7.2 months). Conclusions: A prognostic model was developed composed of 3 readily available clinical parameters for PFS and 4 clinical parameters for OS to help stratify patients into favorable, intermediate, and poor prognosis groups for the treatment of everolimus in clear cell RCC patients. These risk groups can be used by physicians to identify patients most likely to respond to everolimus. Results of the analysis will be presented.