Abstract
BACKGROUND: In China, the risk stratification system for thyroid nodules has not yet reached a uniform consensus. Therefore, the purpose of this study was to compare the effectiveness of the Chinese Thyroid Imaging Reporting and Data Systems (C-TIRADS), American College of Radiology TIRADS (ACR-TIRADS), European TIRADS (EU-TIRADS), and Korean TIRADS (K-TIRADS) in distinguishing benign from malignant thyroid nodules and guiding fine-needle aspiration (FNA). METHODS: A total of 1,174 thyroid nodules from 1,174 patients with an average age of 45.86±13.66 years were included in our study. Ultrasound features of the nodules were evaluated and categorized according to the four thyroid risk stratification systems. These TIRADSs were compared by using the area under the receiver operating characteristic curve (AUROC) and the optimal cut-off classification was determined from the four systems and the diagnostic performance of the corresponding recommended FNAs was compared. RESULTS: Out of the 1,174 thyroid nodules, 699 were benign, and 475 were malignant. The best diagnostic performance cut-off categories for each risk stratification system were C-TIRADS 4B [area under the curve (AUC) =0.864], ACR-TIRADS 5 (AUC =0.882), EU-TIRADS 5 (AUC =0.861) and K-TIRADS 5 (AUC =0.856). The AUROC of ACR-TIRADS 5 was significantly greater than those of C-TIRADS 4B, EU-TIRADS 5, and K-TIRADS 5 (vs. C-TIRADS 4B, P=0.0191; vs. EU-TIRADS 5, P=0.0031; vs. K-TIRADS 5, P=0.0001). Comparisons of the AUROCs of C-TIRADS 4B, EU-TIRADS 5, and K-TIRADS 5 revealed no statistically significant differences (C-TIRADS 4B vs. EU-TIRADS 5, P=0.4184; C-TIRADS 4B vs. K-TIRADS 5, P=0.2388; EU-TIRADS 5 vs. K-TIRADS 5, P=0.4659). The FNA recommendation of CI-TIRADS 4B showed the best FNA diagnostic performance, with an AUROC of 0.658. Compared with those of ACR-TIRADS 5, EU-TIRADS 5, and KI-TIRADS 5, the AUROC of the FNA recommendation of CI-TIRADS 4B was significantly better (all P<0.0001). CONCLUSIONS: All four thyroid risk stratification systems with different geographical settings have high diagnostic performance. FNAs based on C-TIRADS recommendations have significantly better diagnostic performance and may be more suitable for use in patients with thyroid nodules in China.