Evaluation of thyroid nodules with coexistent Hashimoto's thyroiditis according to various ultrasound-based risk stratification systems: A retrospective research

Purposes: To investigate the efficiency of Thyroid Imaging Reporting and Data System (TI-RADS) proposed by KWAK, the American College of Radiology, and the 2015 American Thyroid Association (ATA) guidelines for thyroid nodules with Hashimoto's thyroiditis (HT) and to determine whether HT influence the diagnostic performance of these risk-stratification systems. Methods: A total of 101 nodules with HT and 101 nodules with non-HT were retrospectively analyzed by ultrasound-based diagnostic classifications and compared with histopathological results. The areas under the receiver operating characteristic curve (AUCs) were calculated for comparative analysis. Results: In the HT group, KWAK TI-RADS has the best sensitivity (91.67%), while ACR TI-RADS has the highest specificity (82.93%) and accuracy (81.19%). The AUCs of ACR TI-RADS, ATA guidelines, and KWAK TI-RADS were 0.844, 0.782, and 0.830, respectively. In the non-HT group, the sensitivity and specificity of three riskstratification systems had no significant difference. The AUCs of ACR TI-RADS, ATA guidelines, and KWAK TIRADS were 0.872, 0.839, and 0.874, respectively. No significant difference was found in diagnostic effectiveness of the same systems with both contexts. Conclusions: ACR TI-RADS performed the most effective for thyroid nodules in HT, whereas KWAK TI-RADS was the best for those in non-HT. Both of TI-RADS (ACR and KWAK) provided higher diagnostic effectiveness than ATA guidelines in HT or in non-HT. Moreover, HT could not affect the diagnostic performance of these riskstratification systems.