Efficacy of traditional and alternative sunitinib treatment schedules in Japanese patients with metastatic renal cell carcinoma

We report the adverse events and efficacy of traditional (4 weeks on 2 weeks off) and alternative sunitinib treatment schedules for Japanese patients with metastatic renal cell carcinoma. We retrospectively investigated 54 patients who received sunitinib for metastatic renal cell carcinoma between May 2006 and June 2012: 32 received a traditional treatment schedule and 22 received an alternative schedule. According to the Memorial Sloan-Kettering Cancer Center risk classification, five patients had favorable prognoses, 42 had intermediate prognoses and seven had poor prognoses. The mean observation periods were 16.3 and 20 months for the traditional and alternative schedule groups, respectively. Adverse events were significantly less common in the alternative schedule group, including most high-grade events. In the traditional and alternative schedule groups, median times to failure were 4.1 and 11.6 months (P = 0.040), median progression-free survival times were 4.1 and 11.3 months (P = 0.031), and median overall survival times were 12.0 and 32.1 months (P = 0.018), respectively. Each of these measures was better in the group of patients who received an alternative treatment schedule, suggesting that individualized changes to the sunitinib administration schedule can be effective.