Response to sunitinib in patients with metastatic renal cell carcinoma: Experience of one center.

e15603 Background: Five-years survival of patients with metastatic renal cell carcinoma (mRCC) is only 10%. A complete response (CR) to therapy is rare but has been achieved in minority of patients using high-dose interleukin-2. Sunitinib is an oral multitargeted receptor tyrosin kinase inhibitor and is currently considered the standard of care for first-line therapy of mRCC. CRs and long-term responders (LTR) to sunitinib have been documented in the literature. However, a detailed description and analysis of these patients is lacking. We report LTR, defined as patients achieving ongoing CR or remaining progression-free for ≥ 18 months on sunitinib. Methods: From 10/2008 till 12/2012, 48 patients were treated with sunitinib (50 mg/day, 4 weeks on/2 weeks off) as the first line therapy of clear cell mRCC. Tumor assessments were performed at baseline and every two cycles thereafter until the end of treatment, using RECIST criteria. Results: Nine patients were identified as LTR (18.8%). Retrospective data of...