Patients are planned to be treated with a dose of apatinib 500 mg(BSA ≤1.5) or 750mg(BSA>1.5) once daily. The dose was reduced or temporarily suspended according to predefined rules and after considering any observed toxicity, which was assessed according to the Common Terminology Criteria for Adverse Events version 3.0. Following adverse event resolution, apatinib can be restarted at the maximally tolerated dose and continued until progression, unacceptable toxicity or patient refusal. The study was approved by participating hospital review boards, and conducted according to the Declaration of Helsinki and the International Conference on Harmonization of Good Clinical Practice guidelines. Each patient provided written informed consent.