Diagnostic and Therapeutic Approaches to Radioactive Iodine Refractory Differentiated Thyroid Cancer / 대한이비인후과학회지

ABSTRACT

Unlike most thyroid cancers which have an excellent prognosis with standard treatments such as surgery and additional radioactive iodine therapy followed by long term TSH suppression, 15-20% of differentiated thyroid cancers are unresponsive, showing locally aggressive behavior or distant metastasis. It has been reported that the ability of iodine uptake among residual follicular cells is usually impaired in such unresponsive cases. As the general incidence of thyroid cancer increases, the number of this radioactive iodine refractory disease is also increasing. This becomes clinically challenging because iodine-based diagnostic and therapeutic approaches are not applicable anymore. Moreover, other conventional modalities including radiotherapy or cytotoxic chemotherapy is neither effective in this subset of thyroid cancer. So many researches are currently under way to find effective molecular targeted therapies, which will play a role in the treatment of these unresectable and advanced cases. This review discusses the recent research progress regarding the iodine avidity of follicular cells in thyroid cancer, and outcomes of clinical studies using targeted agents.