Sunitinib, an oral small molecular multipletarg-eted receptor tyrosine kinase (RTK) inhibitor, has a relatively board spectrum of targets, including the vascular endothelial growth factor receptors (VEGFRs); platelet-derived growth factor receptors (PDGFRs); the stem cell factor receptor (c-KIT) and FMS-like tyrosine kinase 3(FLT3) [1–4], thereby exhibiting both anti-angiogenesis and anti-tumor activities. The gene discussed is FLT3; the disease is neoplasm.