Accuracy of Thyroid Imaging Reporting and Data System in the Detection of Malignancy Risk of Thyroid Nodules in Relation to Fine-needle Aspiration Bethesda System Findings: A Tertiary Center Experience

Objectives: This study aims to evaluate the accuracy of the thyroid imaging reporting and data system (TI-RADS) in predicting malignancy risk in thyroid nodules and to compare the TI-RADS findings with the fine-needle aspiration (FNA) Bethesda System in a tertiary center. Methods: A retrospective analysis was conducted on 1421 patients who underwent ultrasound-guided FNA between January 2021 and September 2023. Thyroid nodules were classified according to TI-RADS criteria and compared with cytological findings based on the Bethesda System. Sensitivity, specificity, and odds ratios (ORs) were calculated to evaluate the diagnostic performance of TI-RADS in forecasting thyroid malignancy. Results: The mean age of the studied population was 48.2 ± 14.2 years, with 82.1% females and 17.9% males. Malignant nodules were associated with significantly higher TI-RADS scores ( P < 0.001). TI-RADS 5 (highly suspicious) demonstrated the highest malignancy risk with an OR of 4.28 (95% confidence interval: 2.76–6.64) and an accuracy of 83.0% ( P < 0.001). Male gender, solitary nodules, taller-than-wide shape, very hypoechoic texture, and punctate echogenic foci were all significantly correlated with malignancy ( P < 0.001). Conclusion: TI-RADS, particularly when combined with FNA Bethesda System findings, provides a reliable tool for stratifying thyroid nodule malignancy risk. Its use in clinical decision-making can enhance diagnostic accuracy and improve the patient outcomes by minimizing unnecessary invasive procedures.