Lenvatinib is a multi-target kinase inhibitor (MKI) targeting vascular endothelial growth factor receptors 1–3 (VEGFR1–3), fibroblast growth factor receptors 1–4 (FGFR-1–4), RET, c-kit, and platelet-derived growth factor receptor α (PDGFRα), approved for treatment of radioactive iodine (RAI)-refractory differentiated thyroid cancer (DTC) [2]. This evidence concerns the gene FGFR1 and differentiated thyroid carcinoma.