Biweekly sunitinib regimen reduces toxicity and retains efficacy in metastatic renal cell carcinoma: A single-center experience with 31 patiens

Objectives: Sunitinib is the standard care for first-line treatment of metastatic renal cell carcinoma. The aim of this study was to determine whether a sunitinib regimen of 50 mg/day 2-weeks on/1-week off could maintain the same dose-intensity as the standard 4-weeks on/2-weeks off schedule, and provide the same efficacy in terms of objective response, progression-free survival and overall survival, while reducing drug-related toxicity. Methods: A total of 31 patients with metastatic renal cell carcinoma received sunitinib orally at the dose of 50 mg/day in a 2-weeks on/1-week off regimen until disease progression or intolerable toxicities occurred. Results: All enrolled patients were assessable in terms of toxicity and response. They received treatment for a median of 16 months (range 2.0–36.0+ months). A total of 13 patients (42%) obtained an objective response; disease stabilization was achieved in 10 patients (32%), whereas eight patients (26%) experienced disease progression. The most important toxicities were anemia, gastrointestinal effects, fatigue and hypertension, but they were all controlled. Conclusions: Sunitinib 50 mg given orally in a 2-weeks on/1-week off regimen can provide a high response rate and avoid drug-related toxicities, achieving the same dose intensity as the standard schedule, and probably longer disease control. Key words: metastatic renal cell carcinoma, renal cancer medical treatment, sunitinib, treatment toxicity, tyrosine kinase inhibitors.