Sorafenib is a multitargeted, small molecule TKI that inhibits pathways important in cellular proliferation (i.e., RAF-1, B-type Raf [BRAF], and c-Kit) and pathways that are pivotal in tumor angiogenesis (i.e., VEGFR-2, VEGFR-3, FLT-3, and PDGFR-β) [37]. This evidence concerns the gene PDGFRB and neoplasm.