For High-Definition, Click
Surgery followed by adjuvant treatment with radioactive iodine (RAI) is a highly effective treatment for a majority of patients diagnosed with differentiated thyroid cancer (DTC). However, RAI resistance occurs in approximately 10-20% of patients, making them eligible for targeted therapy. Certain histologic subtypes suggest more advanced disease, indicating a future need for targeted therapies, notes Gary L. Clayman, DMD, MD.
Until recently, there were few therapies available for patients with RAI-refractory thyroid cancer, notes Francis P. Worden, MD. For patients presenting with RAI-refractory disease, Worden recommends a clinical trial exploring TKIs. Studies are currently exploring the TKIs lenvatinib and vandetanib as treatments in DTC. Additionally, the TKI sorafenib was approved based on results from the phase III DECISION trial.
Although TKIs are impactful in DTC, they do not cure patients of the disease. As a result, Worden's preference is to begin with a clinical trial followed by sorafenib. In off-label situations, Worden notes having used mTOR inhibitors, such as rapamycin, in the past with success.