Abstract:Objective: To compare the diagnostic efficacy of C-TIRADS and ACR TIRADS for benign and malignant thyroid nodules. Methods: A retrospective analysis was performed on 321 thyroid nodules undergoing fine needle aspiration. The data of ultrasonographic image were collected. Ultrasonic physicians re-graded all nodules by C-TIRADS guideline and ACR TIRADS guideline. The receiver operating characteristic (ROC) curve of them was constructed, and the sensitivity, specificity and accuracy of C-TIRADS and ACR TIRADS were calculated and their diagnostic efficacy for thyroid nodules were compared. Results: By C-TIRADS guideline, the risks of malignant thyroid nodules were as follows: 0.0% (0/10) in category 2, 5.0% (1/20) in category 3, 17.3% (22/127) in category 4a, 44.3% (43/97) in category 4b, 74.4% (32/43) in category 4c, and 91.7% (22/24) in category 5. By ACR TIRADS: 4.3% (1/22) in category 2, 3.4% (2/58) in category 3, 35.9% (52/145) in category 4, and 64.6% (62/96) in category 5. The area under curve (AUC) of C-TIRADS and ACR TIRADS were 0.798 (95%CI=0.749–0.840) and 0.765 (95%CI=0.715–0.810) , respectively, without statistically significant difference (P=0.081) . The maximum value of the Youden index was 0.467 and 0.382, and the corresponding cutoff values were C-TIRADS 4a and ACR-TIRADS 4, respectively. The sensitivity, specificity and accuracy of C-TIRADS were 81.82%, 84.00%and 83.18%, respectively, and those of ACR TIRADS were 81.82%, 60.00%and 68.22%respectively. The specificity and accuracy of C-TIRADS were higher than those of ACR TIRADS, and the difference was statistically significant (P=0.000, P=0.000) , but there was no statistically significant difference in sensitivity (P=1.000) . Conclusion: C-TIRADS has better specificity and accuracy than ACR TIRADS in diagnosis of thyroid nodules.
