Objective:
To evaluate the efficacy of the ultrasound based Thyroid Imaging Reporting and Data System
(TIRADS)in estimating risk of malignancy in thyroid nodules by correlating it with Bethesda system of thyroid
cytopathology.
Methods:
A retrospective single center study was conducted in a specialty hospital in UAE from November 2017 to
November 2019 on 259 thyroid nodules which underwent ultrasound and fine needle aspiration cytology (FNAC). Thyroid
nodules were evaluated using American College of Radiology (ACR) TIRADS and categorized as benign (TR1), not
suspicious (TR2), mildly suspicious (TR3), moderately suspicious (TR4), or highly suspicious (TR5) for malignancy. The
risk of malignancy associated with each TIRADS category was evaluated by comparing it with the Bethesda system
classification of cytopathology.
Results:
Ultrasound and FNAC data of 259 nodules was reviewed. Out of these 33 (12.7%) nodules were excluded because
FNAC revealed atypia of undetermined significance or follicular lesion of undetermined significance. The estimated risk of
malignancy in TR 3 was 13.6%, in TR4 was 27% and TR5 was 63.6%. There was statistically significant correlation
between –TIRADS and Bethesda system using Chi-square test (p<0.001). The receiver operating curve (ROC) analysis
revealed specificity of 81.3 % [95% CI, 74.9-86.6%], NPV of 91 % [95% CI, 87.1–93.8%] and accuracy of 77.9% [95% CI,
71.9–83.1%] in differentiating benign from malignant nodules.
Conclusion:
The ultrasound based ACR- TIRADS scoring correlates well with the Bethesda cytopathology in thyroid
nodule risk stratification. Thus, it can be used as a simple and effective tool to decide further management and avoid
unnecessary FNAC and surgeries in thyroid nodules.
Interest of researchers in ultrasound systems for risk stratification of thyroid nodules (TIRADS): a systematic review
