부산대학교 도서관

Radioiodine has been effectively applied for the management of hyperthyroidism and differentiated thyroid cancers in most countries of the world. The majority of thyroid cancers are differentiated thyroid cancer that has an overall excellent prognosis, which attributed to appropriate treatment of the disease including administration of radioiodine, I-131. I-131 therapy has usually been undertaken for the ablation of remnant tissue or adjuvant treatment after surgical resection of the thyroid. I-131 therapy was routinely recommended for patients with high-risk disease, and should be considered for intermediate-risk disease as an adjuvant purpose. Several latest studies refute worries of increase cancer risk with I-131 treatment for thyroid cancer. Thus, recent ATA guidelines have shifted toward a more individual and stratified approach, because of benign nature of the differentiated thyroid cancer as well as awareness of side effects including potential increasing incidence of second primary malignancy after I-131 treatment. While some retrospective studies also pointed out that potential increases in cancer development after I-131 treatment for hyperthyroidism recently. Treatment decisions regarding the use of radioiodine therapy should consider the balance of risks and benefits for individual patients with low risk differentiated thyroid cancer and hyperthyroidism, if it is true. Thus, we will review current understanding for the association of increased secondary malignancy and I-131 treatment of thyroid diseases.