The role of external-beam radiotherapy for differentiated thyroid cancer.

The treatment options for differentiated thyroid cancer (DTC) are surgery, thyroid stimulating hormone suppression, radioactive iodine, and multitargeted tyrosine kinase inhibitors. The role of external-beam radiotherapy (EBRT) for DTC is controversial because of the lack of randomized controlled trials, but prospective single-arm studies and propensity score matching analyses have shown its efficacy and safety. This review discusses the role of EBRT after resection of gross disease, when there is a high risk of locoregional failure, as well as its role for locoregionally gross recurrent and unresectable disease. As in other tumor sites, EBRT has an important role in the palliative management and local control of patients with metastatic DTC, especially with bone and brain metastases.