Outcome of third-line sunitinib after sequential therapy with cytokines and sorafenib in metastatic renal cell carcinoma

Third-line sunitinib is occasionally used for selected patients with metastatic renal cell carcinoma (mRCC). The aim of the present study was to evaluate the clinical significance of third-line sunitinib after failure of first-line cytokine therapy and second-line sorafenib in patients with clear-cell mRCC. A total of 14 consecutive patients with clear-cell mRCC treated with third-line sunitinib between December 2008 and February 2012 were enrolled in the present study. Disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and relative dose intensity (RDI) were compared with those of first-line (n=20) and second-line (n=14) sunitinib treatment. The DCR was 42.9%, the median PFS was 12.0 months, and the median OS was 20.0 months for third-line sunitinib; there were no statistically significant differences compared with first-line and second-line sunitinib. The mean RDI was significantly lower for third-line sunitinib compared with first- and second-line sunitinib (P=0.0003 and 0.0109, respectively). Therefore, third-line sunitinib is an effective treatment option for selected patients with mRCC, as optimized therapeutic efficacy was obtained with a relatively low dose of sunitinib.