Update on multikinase inhibitor therapy for differentiated thyroid cancer.

Curative therapies for radioiodine-refractory differentiated thyroid cancer remain lacking. However, oral multikinase inhibitors often allow for disease control and improved progression-free survival. Two agents, lenvatinib and sorafenib, have been approved for radioiodine-refractory differentiated thyroid cancer on the basis of phase III clinical trials showing marked response rates and improved progression-free survival over placebo. Several other multikinase inhibitors, including apatinib, axitinib, cabozantinib, pazopanib, sunitinib and vandetanib, have also been studied in phase II clinical trials, with varying response rates and comparable progression-free survival. Selective kinase inhibitors, including dabrafenib, vemurafenib, selumetinib and gefitinib, offer a more targeted approach and have also been studied in phase II clinical trials. While the emergence of these treatments has changed the landscape of management of advanced thyroid cancer, clinical challenges remain, and there are many areas of ongoing research.