FLT4 and thyroid cancer: Combination treatment prolonged the survival of mice via MAPK signaling pathway blockade.347 Although patients could significantly benefit from lenvatinib (E7080, multitarget inhibitor, mostly for VEGFR-2 (KDR)/VEGFR3 (Flt-4)), the adverse effect of lenvatinib was not tolerated in patients with radioiodine-refractory thyroid cancer.348 Lenvatinib plus the MEK inhibitor selumetinib (AZD6244) promoted the anticancer effect in mice with anaplastic thyroid cancer.