Radioactive iodine ablation therapy reduces the risk of recurrent disease in pediatric differentiated thyroid carcinoma

Background: While radioactive iodine (RAI) therapy in older adults with differentiated thyroid carcinoma (DTC) reduces recurrence, data in pediatrics remain limited. We conducted a meta-analysis to quantify outcomes and recurrence risk with RAI versus thyroidectomy alone in the pediatric population. Methods: Systematic literature review identified 34 retrospective studies including 2913 DTC patients under age 22 years (published 2005-2023). Meta-analysis calculated pooled rates of disease persistence and recurrence. Relative risk ratios compared odds of recurrence with RAI versus no RAI. Results: Patients had mean age 14.7 years (95 % CI, 14.2-15.2) and were 75.9% female (95% CI, 73.8-78.1 %). Majority (90.2 %) received RAI. Pooled persistence rate was 30.3 % (95 % CI, 21.7-39.5 %); higher with RAI (31.5 %; 95% CI, 22.4-41.3 %) than no RAI (4.5 %; 95% CI, 0.0-18.7 %) (OR 3.28; 95% CI,1.82-5.91; p < 0.001). Recurrence rate was 8.97 % (95 % CI, 4.78-14.3 %). Those with RAI had 53.1 % lower recurrence risk versus no RAI (RR 0.47; 95 % CI, 0.27-0.82; p = 0.007). Median follow-up was 7.2 years (95 % CI, 5.8-8.5 years), with no association between follow-up duration and recurrence (r =-0.053; p = 0.80). Conclusions: RAI therapy as an adjunct to thyroidectomy is associated with a significantly lower risk of long-term recurrence in pediatric DTC. These findings advocate for the use of RAI in preventing recurrence among high-risk pediatric patients with DTC.