Diagnostic Values of Solid Features in Different Sizes Thyroid Nodules Based on C-TIRADS

Objective: As a positive features in C-TIRADS (Chinese Thyroid Imaging Reporting and Data System) guidelines, solid features represent the latest positive indicator, which differs from those in other guidelines. This study was to explore the diagnostic value of the solid features for thyroid nodules of different sizes. Methods: Between January 2022 and October 2023, a total of 1561 patients with 1790 thyroid nodules confirmed by surgical pathology were prospectively included in this study. These nodules were divided into three groups based on their maximum diameter: Group A 1 (≤ 10mm), Group A 2 (> 10mm, < 20mm), and Group A 3 (≥ 20mm). The component characteristics of thyroid nodules in each group were analyzed. Based on the surgical pathology results, Receiver Operating Characteristic (ROC) curves were constructed to evaluate the diagnostic efficiency of C-TIRADS solid features for thyroid nodules of different sizes. Results: As the size of thyroid nodules increased, the incidence of cystic changes in both benign and malignant nodules showed a linear increasing trend (Z-values of 46.251 and 156.586, respectively; P values < 0.001 for both). The occurrence rate of solid malignant nodules was higher than that of benign nodules in all groups, with Area Under Curve (AUC) values of 0.620, 0.723, and 0.767, respectively. Conclusion: With the increase in the size of thyroid nodules, the diagnostic value of solid features for thyroid cancer progressively increases. The specificity of thyroid nodule diagnosis also increases progressively. Which may have certain value in the evaluation process using C-TIRADS, particularly in the management of thyroid nodules in clinical settings. Keywords: C-TIRADS, ultrasound, thyroid nodule