KIT and neoplasm: Sorafenib is a bis-aryl urea chemical compound that has anticancer action based on inhibition of angiogenesis (tumor blood supply) and tumor cell proliferation (tumor growth) through the blockage of Raf/MEK/ERK and JAK/STAT signaling pathways and through the inhibition of multiple tyrosine kinases of such receptors as vascular endothelial growth factor receptor (VEGFR)-2, VEGFR-3, platelet-derived growth factor receptor beta (PDGFRβ), FMS-like tyrosine kinase 3 (FLT3), rearranged during transfection receptor (RET) and tyrosine-kinase receptor (KIT) [7].