Prognostic Factors Affecting Iodine-131 Treatment Efficacy in Patients With Differentiated Thyroid Carcinoma: A Risk-Stratified Analysis

To analyze factors influencing iodine-131 (I-131) treatment efficacy in differentiated thyroid carcinoma (DTC). This retrospective study classified 299 patients with DTC into medium-low-risk and high-risk groups, assessing clinical data (preoperative stimulated thyroglobulin [ps-Tg], urinary iodine, gender, T stage, diet). Patients followed normal or iodine-restricted diets. Statistical analyses included t-tests, chi-squared tests and logistic regression. Medium-low risk and higher ps-Tg levels and urinary iodine concentrations correlated with less favorable outcomes (<i>p</i> < 0.001). High-risk patients showed significant differences in gender, T stage and ps-Tg level (<i>p</i> < 0.001). Multivariate analysis identified risk level, T stage and ps-Tg level as key prognostic factors (<i>p</i> < 0.001), with urinary iodine concentration having a minor effect (<i>p</i> = 0.003). Risk stratification, T stage and ps-Tg level were the primary prognostic determinants. Dietary interventions showed different effects in different risk-stratified patients, requiring individualized consideration. These findings emphasize the importance of comprehensive assessment in DTC management.