Clinical Application of C-TIRADS Category and Contrast-Enhanced Ultrasound in Differential Diagnosis of Solid Thyroid Nodules Measuring ≥1 cm.

BACKGROUND The aim of this study was to investigate the performance of Chinese Thyroid Imaging Reporting and Data System (C-TIRADS) category combined with contrast-enhanced ultrasound (CEUS) in diagnosing thyroid cancer. MATERIAL AND METHODS From October 2020 to March 2021, 116 thyroid nodules from 113 patients who underwent conventional ultrasound and CEUS examinations at the General Hospital of Northern Theater Command were reviewed. In the conventional ultrasound examination, thyroid nodules were categorized by C-TIRADS. The nodules were reclassified based on CEUS scoring, then a combined diagnosis was made. The pathological results were taken as the criterion standard. To compare the diagnostic performance of the 3 methods according to the receiver operating characteristic curves produced for thyroid nodules. RESULTS After chi-square test, the 7 characteristics of enhancement patterns, internal homogeneity, wash-in, wash-out, ring enhancement, morphology, and contrast agent retention characteristics (CAR) were statistically different between malignant and benign tumors; A high diagnostic performance was demonstrated by C-TIRADS combined with CEUS in diagnosing thyroid cancer. The area under the curve (AUC), the sensitivity, and the specificity of C-TIRADS combined with CEUS for diagnosing thyroid cancer were 0.918 (95% CI: 0.852-0.961), 80.9% (95% CI: 69.1-89.8%), and 90.6% (95% CI: 79.3-96.9%), respectively. The AUC of C-TIRADS alone was significantly lower than that of C-TIRADS combined with CEUS (P=0.0056), while there was no significant difference between CEUS and C-TIRADS combined with CEUS (P=0.59). CONCLUSIONS The combined method of C-TIRADS and CEUS, with reduced rate of thyroid nodule biopsy and clinical application value, has higher diagnostic accuracy than the single diagnosis method.