Purpose: To compare the value of Thyroid Imaging Reporting and Data Systems proposed by Kwak (KWAK-TIRADS) and ACR (ACR TI-RADS) and 2015 American Thyroid Association (ATA) guidelines in the diagnosis of surgically resected thyroid nodules.
Methods: From January 2015 to December 2015, 2544 thyroid nodules in 1758 patients who underwent thyroidectomy at our center were included. The KWAK-TIRADS category, ACR TI-RADS and ultrasound (US) pattern based on ATA guidelines were assigned to each thyroid nodule. Nodules were divided into groups according to their maximal diameter further.
Results: Of all the nodules, 863 (33.9%) were benign, whereas 1681 (66.1%) were malignant. The malignancy percentage of ACR TI-RADS category 1, 2, 3, 4, and 5 were 0%, 1.3%, 9.1%, 52.5%, and 88.8%, respectively. KWAK-TIRADS and ATA guidelines showed a better diagnostic efficiency than ACR TI-RADS (P < 0.01). ACR TI-RADS demonstrated a higher specificity (79.7%, P < 0.05), whereas the ATA US pattern had a higher sensitivity (95.5%, P < 0.01). The TIRADS (KWAK-TIRADS and ACR TI-RADS) category and ATA guidelines performed better in differentiating nodules >1 cm. KWAK-TIRADS showed better diagnostic efficiency than the other methods in differentiating nodules >1 cm (AUC: 0.92, P < 0.01).
Conclusions: KWAK-TIRADS and ATA guidelines provide a better diagnostic efficiency than ACR TI-RADS. The TIRADS (KWAK-TIRADS and ACR TI-RADS) category and ATA guidelines perform better in differentiating nodules >1 cm than nodules ≤1 cm. KWAK-TIRADS perform better in differentiating nodules >1 cm than other methods.
Keywords: 2015 American Thyroid Association management guideline; Thyroid Imaging Reporting and Data System; Thyroid nodules; Ultrasound.