External Beam Radiotherapy for Thyroid Malignancy

Although surgery is the mainstay of treatment in thyroid cancer (but not thyroid lymphoma), there is a role for external beam radiotherapy (EBRT). The evidence comes mainly from single institution retrospective data but is now supported by results of meta-analyses. These results are reviewed as are treatment guidelines describing the recommendations for EBRT. This chapter describes the evidence for adjuvant, unresectable, and palliative radiotherapy in differentiated thyroid cancer (DTC), medullary thyroid cancer (MTC), and anaplastic thyroid cancer (ATC). The role of EBRT in palliating symptoms from metastatic disease and the use of stereotactic radiotherapy is described as is the role of EBRT in the treatment of thyroid lymphoma. The technical aspect of delivering EBRT, including stereotactic radiation in metastatic disease and the potential side effects of EBRT, is also reviewed.