CXCL7 is a predictive marker of sunitinib efficacy in clear cell renal cell carcinomas

Background:Sunitinib is one of the first-line standard treatments for metastatic clear cell renal cell carcinoma (ccRCC) with a median time to progression shorter than 1 year. The objective is to discover predictive markers of response to adapt the treatment at diagnosis.Methods:Prospective phase 2 multi-centre trials were conducted in ccRCC patients initiating sunitinib (54 patients) or bevacizumab (45 patients) in the first-line metastatic setting (SUVEGIL and TORAVA trials). The plasmatic level of CXCL7 at baseline was correlated with progression-free survival (PFS).Results:The cut-off value of CXCL7 for PFS was 250 ng ml-1. Patients with CXCL7 plasmatic levels above the cut-off at baseline (250 ng ml-1) had a significantly longer PFS (hazard ratio 0.323 (95% confidence interval 0.147-0.707), P=0.001). These results were confirmed in a retrospective validation cohort. The levels of CXCL7 did not influence PFS of the bevacizumab-treated patients.Conclusions:CXCL7 may be considered as a predictive marker of sunitinib efficacy for ccRCC patients.