Background: Treatment of everolimus-resistant disease remains largely undefined in metastatic renal cell carcinoma (mRCC). We report on 40 patients (pts) who receive systemic treatment after failure of everolimus.
Patients and methods: Forty pts received sunitinib (n=19), sorafenib (n=8), dovitinib (n=10) or bevacizumab/interferon (n=3) after failure of everolimus. Median progression-free survival (PFS), overall survival (OS) and best tumour response (according to Response Evaluation Criteria In Solid Tumors) were analysed retrospectively. Kaplan-Meier, log-rank test and Cox regression analyses were used to estimate or predict OS and PFS.
Results: Treatment of everolimus-resistant disease was associated with a PFS of 5.5 months. (range 0.4-22.3) and an objective partial remission (PR) in 4 pts (10%) and stable disease (SD) in 22 pts (55%). In univariate analyses, first-line treatment with sorafenib was the only variable to correlate with a prolonged PFS of treatment in everolimus-resistant disease (P=0.036). However, its significance as a predictive marker for subsequent therapy could not be verified in multivariate analyses.
Conclusions: Vascular endothelial growth factor targeted therapy shows promising activity in everolimus-resistant metastatic renal cancer and warrants further studies.