Correlation between Sonographic Features of Thyroid Nodules Based on Thyroid Imaging Reporting and Data System (TIRADS) Classification and Fine Needle Aspiration Cytology (FNAC) Results

Open Access

Abstract

Introduction: Thyroid nodules are common, with most being benign, but a small proportion carries a risk of malignancy. Accurate risk stratification is essential to guide management and avoid unnecessary invasive procedures. Fine-needle aspiration cytology (FNAC) is the gold standard for diagnosis, while the Thyroid Imaging Reporting and Data System (TIRADS) standardizes ultrasound evaluation and estimates malignancy risk. Methods & Materials: This cross-sectional observational study was conducted in the Department of Radiology & Imaging, Combined Military Hospital (CMH), Dhaka, over six months from January 2024 to June 2024. A total of 160 patients with thyroid nodules detected on ultrasonography (USG) were the study subjects. Data were analyzed using SPSS version 23.0. Result: Among 160 patients, most were female (80%) with a mean age of 41.6 ± 12.8 years, and the majority presented with painless neck swelling (82.5%). On ultrasonography, 25% of nodules were TIRADS 2, 30% TIRADS 3, 27.5% TIRADS 4, and 17.5% TIRADS 5. FNAC showed 67.5% benign, 8.8% indeterminate, 6.2% follicular neoplasm, 7.5% suspicious, and 10% malignant nodules. Malignancy risk increased with higher TIRADS grades, and TIRADS demonstrated high sensitivity (83.3%), specificity (81.2%), accuracy (81.9%), and NPV (94.7%), confirming its reliability for malignancy risk stratification. Conclusion: This study demonstrated a strong correlation between sonographic features of thyroid nodules, as classified by TIRADS, and FNAC results, with diagnostic performance showing high sensitivity, specificity, and negative predictive value. The malignancy risk increased with higher TIRADS grades, confirming the utility of TIRADS as a reliable, non-invasive risk stratification tool.