TI-RADS Scoring in Surgical Decision-Making for Bethesda III Thyroid Nodules: A Retrospective Analysis

Objective: To evaluate the contribution of ACR TI-RADS scoring system to surgical decision-making in Bethesda category III thyroid nodules and investigate its role in malignancy risk stratification. Methods: This retrospective cross-sectional study evaluated 285 patients with 294 thyroid nodules classified twice as Bethesda category III who underwent thyroidectomy at a tertiary care center between 2018-2023. ACR TI-RADS scores were calculated based on standardized ultrasonographic features. Primary outcome was malignancy rate according to histopathological examination. Statistical analyses included chi-square test, Mann-Whitney U test, and logistic regression. Results: Among 294 nodules, malignancy was detected in 39.8% (n=117). TI-RADS categories showed progressive malignancy rates: TI-RADS 2 (26.9%), TI-RADS 3 (32.0%), TI-RADS 4 (41.5%), and TI-RADS 5 (82.8%). Logistic regression identified age (OR=0.95), hypoechogenicity (OR=2.92), and microcalcification (OR=3.65) as independent predictors. The scoring system demonstrated 57.0% sensitivity, 90.0% specificity, 82.8% positive predictive value, and 73.1% negative predictive value for TI-RADS 5 versus TI-RADS 2. Conclusion: ACR TI-RADS scoring system provides valuable contribution to surgical decision-making in Bethesda category III thyroid nodules through its high specificity and positive predictive value, particularly for TI-RADS 5 category.