RecruitingPhase 2Drug trialBIOmarker Driven Trial of VEGFR2 Inhibitor in Advanced or Metastatic SarcomaThe aim of this study is to evaluate the efficacy and safety of Apatinib monotherapy for relapsed or refractory advanced bone and soft tissue sarcoma with VEGFR-2 (KDR) 604A\>G polymorphism as predictive biomarker