Differentiating Benign and Malignant Thyroglossal Duct Cysts With Ultrasonography, CT, and PET/CT

ABSTRACT Background Purpose To determine if US, CT, and/or 18 F‐FDG PET/CT can differentiate benign and malignant thyroglossal duct cysts (TGDCs). Methods In this retrospective review, we identified 72 patients with cytologically proven benign TGDCs and 11 patients with cytologically proven malignant TGDCs. Patient demographics, US and CT features, and maximum standardized uptake value (SUVmax) on PET/CT were compared. On US, TGDCs were assigned a summary score with one point each for irregular margins, solid‐component appearance, vascular flow on Doppler US, and calcifications. Score performance in differentiating benign and malignant TGDCs was analyzed. Results Malignant TGDCs were detected at a younger age (optimal cut‐off, 43.5 years) ( p = 0.001) and were larger (optimal cut‐off, >1.9 cm) ( p = 0.041). Malignant TGDCs more frequently had irregular margins on US ( p