Cabozantinib for the treatment of patients with metastatic variant histology renal cell carcinoma (vhRCC): A retrospective study.

478Background: Cabozantinib (C) prolongs overall survival (OS) and progression-free survival (PFS) in patients with metastatic clear-cell renal cell carcinoma (ccRCC) that progressed on first-line VEGFR-TKI. No standard of care systemic therapy exists for the management of patients with metastatic vhRCC. Methods: This is a retrospective, IRB approved study of patients with vhRCC who received C at MD Anderson Cancer Center from January 2014 till June 2016. Information collected from the medical records included the baseline characteristics, toxicity, dose reductions, and OS. A blinded radiologist assessed the radiographic response using RECIST v1.1. Descriptive statistics, the Kaplan Meier method and the log rank test were applied using Microsoft Excel and GraphPad Prism version 6 software. Results: Median PFS was 8.1 months (mos) (95% CI: 5.8-17.8), and median OS was 22.7 mos (95% CI:11-NR), median follow up 13.3 months (95% CI: 9.6-17) . There were no significant differences detected between patients wit...