Efficacy of Adjuvant Radioactive Iodine Therapy in Histological Variants of DTC: A Scoping Review.

Abstract

The efficacy of adjuvant radioactive iodine (RAI) therapy in intermediate- and high-risk differentiated thyroid carcinoma (DTC) remains unclear, particularly for papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC). This scoping review, following PRISMA-ScR guidelines, analyzed studies from PubMed, Scopus, and CINAHL through July 14, 2023. Data on demographics, cancer characteristics, treatment details, and clinical outcomes were extracted. A limited meta-analysis of continuous measures, proportions, and hazard ratios was performed. Nineteen studies were included, revealing significant variability across studies. Meta-analysis was limited to overall survival (OS) in intermediate-risk PTC due to methodological heterogeneity across studies. Kaplan-Meier survival curves were inconsistent, RAI activity was often unreported, and complications of RAI were rarely addressed. Methodological heterogeneity hinders the assessment of adjuvant RAI efficacy between histological variants. Further randomized trials with extended follow-up and improved reporting are needed to better compare the effects of adjuvant RAI in PTC and FTC.