Outcomes of systemic targeted therapy in recurrent renal cell carcinoma treated with adjuvant sunitinib

Objective: To assess the efficacy and tolerability of rechallenge with sunitinib and other targeted therapies (TTs) in patitents with relapsed recurrent renal cell carcinoma (RCC) in the advanced setting. Methods: In this multi-institutional retrospective study, patients with relapsed RCC were rechallenged with sunitinib or other systemic TTs as a first-line therapeutic approach after failed adjuvant sunitinib treatment. Patient characteristics, treatments and clinical outcomes were recorded. The primary endpoint was progression-free survival (PFS). Secondary endpoints were objective response rate (ORR) and overall survival (OS). Results: A total of 34 patients with relapses were recorded, and 25 of these (73.5%) were men. Twenty-five patients were treated with systemic TT: 65% of patients received TT against the vascular endothelial growth factor pathway (including sunitinib), 21.7% received mammalian target of rapamycin inhibitors and 13% received immunotherapy. The median (interquartile range) time to relapse was 20.3 (5.2–20.4) months from diagnosis, and 7.5 months (1.0–8.5) from the end of adjuvant suntinib treatment. At a median follow-up of 23.5 months, 24 of the 25 patients had progressed on first-line systemic therapy. The median PFS was 12.0 months (95% confidence interval [CI] 5.78–18.2). There were no statistical differences in PFS between different treatments or sunitinib rechallenge. PFS was not statistically different in patients relapsing on or after adjuvant suntinib treatment (≤ 6 or >6 months after adjuvant suntinib ending). The ORR was 20.5%. The median OS was 29.1 months (95% CI 16.4–41.8). Conclusions: Rechallenge with sunitinib or other systemic therapies is still a feasible therapeutic option that provides patients with advanced or metastastic RCC with additional clinical benefits with regard to PFS and OS after failed response to adjuvant sunitinib.