Markedly hypoechoic: a new definition improves the diagnostic performance of thyroid ultrasound

• Published in: European radiology 2023-11, Vol.33 (11), p.7857-7865
• Main Authors: Liu, Juan, Luo, Ting, Zhang, Hua, Liu, Hui, Gu, Ying, Chen, Xia, Shi, LiYing, Guan, Ling, Ni, XueJun, Zhang, XinDan, Zhang, RuiFang, Jia, XiaoHong, Dong, YiJie, Zhang, JingWen, Xu, WenWen, Zhou, JianQiao
• Format: Article
• Language: English
• Subjects: Criteria; Diagnostic Radiology; Diagnostic systems; Differential diagnosis; Effectiveness; Humans; Imaging; Internal Medicine; Interventional Radiology; Malignancy; Medical diagnosis; Medicine; Medicine & Public Health; Muscles; Neuroradiology; Nodules; Radiology; Retrospective Studies; Risk Assessment - methods; Sensitivity; Thyroid; Thyroid gland; Thyroid Neoplasms - pathology; Thyroid Nodule - pathology; Ultrasonic imaging; Ultrasonography - methods; Ultrasound
• ISSN: 1432-1084; 0938-7994; 1432-1084
• DOI: 10.1007/s00330-023-09828-1

Objectives To determine the contribution of a modified definition of markedly hypoechoic in the differential diagnosis of thyroid nodules. Methods A total of 1031 thyroid nodules were included in this retrospective multicenter study. All of the nodules were examined with US before surgery. The US features of the nodules were evaluated, in particular, the classical markedly hypoechoic and modified markedly hypoechoic (decreased or similar echogenicity relative to the adjacent strap muscles). The sensitivity, specificity, and AUC of classical/modified markedly hypoechoic and the corresponding ACR-TIRADS, EU-TIRADS, and C-TIRADS categories were calculated and compared. The inter- and intraobserver variability in the evaluation of the main US features of the nodules was assessed. Results There were 264 malignant nodules and 767 benign nodules. Compared with classical markedly hypoechoic as a diagnostic criterion for malignancy, using modified markedly hypoechoic as the criterion resulted in a significant increase in sensitivity (28.03% vs. 63.26%) and AUC (0.598 vs. 0.741), despite a significant decrease in specificity (91.53% vs. 84.88%) ( p   0.05 for both). There was substantial interobserver agreement ( κ  = 0.624) and perfect intraobserver agreement ( κ  = 0.828) for the modified markedly hypoechoic. Conclusion The modified definition of markedly hypoechoic resulted in a significantly improved diagnostic efficacy in determining malignant thyroid nodules and may improve the diagnostic performance of the C-TIRADS. Clinical relevance statement Our study found that, compared with the original definition, modified markedly hypoechoic significantly improved the diagnostic performance in differentiating malignant from benign thyroid nodules and the predictive efficacy of the risk stratification systems. Key Points • Compared with the classical markedly hypoechoic as a diagnostic criterion for malignancy, the modified markedly hypoechoic resulted in a significant increase in sensitivity and AUC. • The C-TIRADS with the modified markedly hypoechoic achieved higher AUC and specificity than that with the classical markedly hypoechoic (p = 0.01 and