Pediatric adaptions are needed to improve the diagnostic accuracy of thyroid ultrasound using TI-RADS.

Background/purpose: Thyroid Imaging Reporting and Data System (TI-RADS) is validated in adults but not yet in children. The purpose of this study was to determine the sensitivity, specificity, and accuracy of TI-RADS in predicting thyroid malignancy for pediatric nodules, and to compare the diagnostic accuracy to the current American Thyroid Association (ATA) guidelines.

Methods: A single institution retrospective review was performed of patients younger than 21 years who underwent thyroid nodule fine needle aspiration biopsy (FNAB). Two radiologists were blinded to the pathology and independently classified all biopsied thyroid nodules based on TI-RADS. ATA and TI-RADS guidelines were analyzed to determine the diagnostic sensitivity and specificity of both scoring systems.

Results: 115 patients (median age 15.5 years, 90 females) with 138 nodules were scored using TI-RADS. There was moderate inter-rater agreement between radiologists (Kappa = 0.51; p < 0.0001). Evaluating several potential TI-RADS criteria, 23.2%-68.1% of nodules were recommended for FNAB, compared to 82.6% of nodules using ATA guidelines. Using TI-RADS ≥ 3 (without size cutoff) as an indication for FNAB had 100% sensitivity with no missed suspicious or malignant nodules on cytology or pathology.

Conclusions: Using TI-RADS for diagnostic management of pediatric thyroid nodules improves accuracy in predicting malignancy.