Outcome of RAI131 Therapy in Patients With Differentiated Thyroid Cancer (Low and Intermediate Risk)

Thyroid cancer is a universally relatively rare neoplasm, accounting for nearly 1-5% of all female cancers and less than 2% of male cancers. In spite of this relatively low incidence, it occupies the first rank among the most common endocrinal malignancies, with a consistent male to female ratio of 1: 3 observed in nearly all ethnic groups and geographic areas.

Differentiated thyroid cancer (DTC) is rated as slowly growing disease with a fairly good outcome where the five-year survival rate for localized tumor is 99.8% Total thyroidectomy, the removal of the entire thyroid gland, is the most common surgical approach-especially for tumors larger than 1 cm, multifocal disease, or suspected lymph node involvement. Lobectomy may be considered for small, low-risk tumors (<1 cm) confined to a single lobe. If lymph node metastasis is evident clinically or radiologically, neck dissection is performed. Postoperative radioactive iodine (RAI) therapy is used to ablate residual tissue or treat recurrent disease, particularly in iodine-avid tumors and intermediate- to high-risk patients. It may not be necessary for small, low-risk tumors. Thyroid hormone suppression therapy with levothyroxine serves both to replace thyroid hormone and suppress TSH, which could stimulate cancer growth. Long-term monitoring includes serial thyroglobulin (Tg) levels (along with anti-Tg antibodies if needed), neck ultrasound, and, in some cases, additional imaging like RAI scans or PET/CT to detect recurrence