Sorafenib is an oral drug that inhibits multiple intracellular kinases (c-CRAF, BRAF, and mutated BRAF) and cell surface receptors (KIT, FLT-3, RET, RET/PTC, VEGFR-1, VEGFR-2, VEGFR-3, and PDGFR-beta), which are involved in the activation of intracellular signaling pathways, leading to the growth and proliferation of tumor cells, in angiogenesis and in the inhibition of apoptosis [7,9,18,19,20]. This evidence concerns the gene RET and neoplasm.