The Value of Chinese Thyroid Imaging Report and Data System Combined With Contrast‐Enhanced Ultrasound Scoring in Differential Diagnosis of Benign and Malignant Thyroid Nodules

Objectives To explore the diagnostic value of contrast‐enhanced ultrasound (CEUS) combined with the Chinese Thyroid Imaging Reporting and Data System (C‐TIRADS) for differentiation of benign and malignant thyroid nodules. Methods A retrospective analysis of the conventional ultrasound and CEUS data of 388 nodules in 355 patients who had undergone thyroid nodule resection was conducted. All nodules had clear pathological results. The CEUS observation indexes included the enhancement degree in the arterial phase (no enhancement, scant punctate‐linear enhancement, mild enhancement, moderate enhancement, and high enhancement) and wash‐out patterns (rapid wash‐out, slow wash‐out, and isochronous wash‐out). Chi‐square test between groups and receiver operating characteristic curves (ROC) were used to determine the malignant (+1 point) and benign (−1 point) observation indexes that were statistically significant for the differentiation between benign and malignant thyroid nodules. The CEUS and C‐TIRADS malignant and benign indexes were combined to score and draw the ROC curve, which was compared with the ROC curve scored by C‐TIRADS alone to compare the diagnostic efficacy of the two methods for differentiating between benign and malignant thyroid nodules. Results Among the CEUS observation indexes, mild enhancement and rapid wash‐out were malignant indexes, while isochronous wash‐out was a benign index. The best diagnostic cut‐off value for the differentiation of benign and malignant thyroid nodules using the C‐TIRADS score and the C‐TIRADS and CEUS combined score (C‐TIRADS + CEUS score) was 2. The sensitivity, specificity, positive predictive values (PPV), and negative predictive values (NPV) of the two methods were 79.97, 75.48, 82.9, 70.5%, and 89.7, 72.9, 83.3, 82.5%, respectively. The area under the curve values were 0.840 and 0.877 ( P < .001), respectively. Conclusions The CEUS feature of mild enhancement in the arterial phase and rapid wash‐out pattern are suggestive of malignancy and isochronous wash‐out pattern is suggestive of benignity. The C‐TIRADS + CEUS score has a higher value for distinguishing benign from malignant thyroid nodules than the C‐TIRADS score alone.