Effectiveness of the TI-RADS Classification in Differentiating Thyroid Nodules: A Sensitivity and Specificity Analysis

Abstract

Thyroid ultrasound provides valuable information about benign or malignant pathologies. The TI-RADS Committee (Thyroid Imaging Reporting and Data System) developed a risk stratification system to classify thyroid nodules based on their ultrasound characteristics. The aim of this study was to determine the diagnostic efficacy of the TI-RADS test in differentiating benign from malignant nodules, using the cytopathological/histopathological results according to the Bethesda anatomopathological classification.

This was a cross-sectional, retrospective, observational study. Based on the information available in the medical records of patients treated at the Hospital Italiano de Córdoba between 2022 and 2023, cases were included if they had both thyroid nodule ultrasound results (evaluated according to TI-RADS) and thyroid tissue biopsy results (classified according to Bethesda), involving individuals over 18 years old of both sexes. A final sample size of 74 cases was achieved.

Of these, 47 (63%) were classified as TI-RADS 4 and 5. Cytology results showed 9 (12%) malignant nodules: 8 (89%) were hypoechoic on ultrasound. The sensitivity of TI-RADS (considering 2 and 3 as benign and 4 and 5 as malignant, compared to Bethesda II as benign and IV, V, and VI as suspicious/malignant) was 88.9%, specificity was 45%, positive predictive value was 22.2%, and negative predictive value was 95.8%.

The TI-RADS classification is useful for the initial evaluation and risk categorization of thyroid nodules due to its high negative predictive value. Its limited specificity suggests the need for additional assessment. These findings support the application of the TI-RADS test in clinical practice, emphasizing the importance of a multidisciplinary approach in the management of thyroid nodules.