A multicenter, prospective phase II trial of gemcitabine plus axitinib in patients with renal cell carcinoma with a predominant sarcomatoid component.

Introduction We conducted a multicenter, phase 2 trial using gemcitabine plus axitinib (GX) in patients with recurrent or metastatic sarcomatoid renal cell carcinoma (SRCC) to evaluate its efficacy and safety. Methods Patients with advanced RCC and a sarcomatoid component of ≥25% on resected kidney or exclusive sarcomatoid carcinoma on needle biopsy were included. Patients received gemcitabine 1000 mg/m2 intravenously on days 1 and 8 of a 3-week cycle and axitinib 5 mg twice daily. Primary endpoint was objective response rate (ORR) according to the response evaluation criteria in solid tumors version 1.1, and secondary end points were progression-free (PFS) and overall (OS) survivals and adverse events. Results Twenty-five patients were enrolled. Median age was 61 (range: 33-80), and 84% were men. The Eastern Cooperative Oncology Group performance status was one in 23 patients (92%). Clear cell carcinoma was the most common histology of the carcinoma component (60%). ORR was 56%, and 28% patients achieved stable disease with a control rate of 84%. With a median follow-up duration of 24.8 months, the median PFS was 4.2 months (95% CI, 2.3-6.1) and median OS was 8.4 months (95% CI 3.3-13.4 months). The most common grade 3 or higher adverse events were neutropenia (36%), hypertension (12%), and anorexia (12%). Most adverse events were manageable, and no unexpected toxicities were found. Conclusion GX showed promising efficacy in patients with SRCC. GX could be considered as a treatment option for patients with SRCC and should be confirmed in larger clinical trials.