Vascular endothelial growth factor receptor tyrosine kinase inhibitor (VEGFR-TKI) rechallenge for patients with metastatic renal cell carcinoma after treatment failure using both VEGFR-TKI and mTOR inhibitor.

Abstract

To assess the efficacy of vascular endothelial growth factor receptor tyrosine kinase inhibitor (VEGFR-TKI) rechallenge for metastatic renal cell carcinoma (mRCC) patients and to identify predictive factors for increased progression-free survival (PFS) or overall survival (OS). The clinicopathological features, outcomes, and prognostic factors of mRCC patients who were treated with VEGFR-TKI after treatment failure using both VEGFR-TKIs and mTOR inhibitors (mTORi) were reviewed. A total of 29 eligible patients were included. Five (17%) patients achieved partial response (PR) with a median response duration of 9.5months (95% CI 5.7-13.4months), and additional 16 patients (55%) achieved stable disease. With a median follow-up period of 19.2months (95% CI 18.9-19.6months), the median PFS and OS were 3.0months (95% CI 1.1-4.9months) and 4.9months (95% CI 2.9-6.8months), respectively. In univariate analysis, the best response to first-line VEGFR-TKI (PR vs. non-PR, p<0.001) and time to rechallenge (TTR, ≤12 monthsvs. between 12 and 24 months vs. >24months, p=0.005) were identified as predictive factors for longer PFS on VEGFR-TKI rechallenge. In addition, an MSKCC risk group (intermediate- vs. poor-risk group, p=0.027), better response at first-line VEGFR-TKI (PR vs. non-PR, p=0.003), and TTR (≤12 monthsvs. between 12 and 24 months vs. >24months, p=0.026) were identified as prognostic factors for longer OS. VEGFR-TKI rechallenge may be a viable option for select metastatic RCC patients who fail both VEGFR-TKI and mTORi therapies.