Imaging Assessment and Management of Pediatric Thyroid Nodules: Emphasis on Application of 2021 K-TIRADS

Pediatric thyroid cancer exhibits different clinical characteristics from those in adults, requiring a tailored approach for imaging evaluation and management. Although thyroid nodules are less common in children, they carry a higher risk of malignancy and often present with cervical lymph node or distant metastases, while long-term outcomes remain favorable. The revised 2021 Korean Thyroid Imaging Reporting and Data System (K-TIRADS) aims to reduce unnecessary biopsies by refining the ultrasound lexicons and biopsy criteria. In pediatric patients, biopsy thresholds for high-suspicion nodules have been lowered, and a risk factor-based strategy has been adopted for intermediate-suspicion nodules. This review summarizes the clinical and molecular features of pediatric thyroid cancer, outlines key updates in the 2021 K-TIRADS, and discusses important considerations for its application in children, with the aim of supporting radiologists in appropriately applying adult-based risk stratification systems in pediatric practice.