|ECR 2019 / C-0774||
|Diagnostic accuracy of TIRADS in evaluation of thyroid nodules|
- When TIRADS 2 & 3 are considered benign and TIRADS 4A, 4B & 5 are considered malignant, TIRADS score had high negative predictive value (98.5%). Therefore, if a nodule was assigned a benign score of TIRADS 2/3, it is highly unlikely to be malignant, thus helping to avoid unnecessary FNAs and / or surgical excision.
- All nodules assigned as TIRADS 2 (benign) turned out to be benign.
- As the TIRADS score increases, the risk of malignancy increases.
- As echogenicity decreases, risk of malignancy increases.
- High specificity for detecting malignancy were noted for marked hypoechogenicity (94.8%), taller than wide shape (98.7%), irregular margin (97.4%) and presence of microcalcification (97.9%). Among these sonographic features, highest specificity was noted for taller than wide shape (98.7%).
- Statistically significant association was noted for the following parameters in detecting malignancy: moderate and marked hypoechogenicity, taller than wide shape, irregular margin, presence of microcalcification and lymph node without fatty hilum.
- Inspissated colloid can mimic microcalcification which can influence the diagnostic performance of TIRADS.
- On retrospective comparison of final pathological diagnosis with the assigned TIRADS score, it was found that majority of benign nodules were assigned benign TIRADS (2 & 3) and all malignancies except 1 were assigned malignant TIRADS score (4A, 4B & 5).
To conclude, using TIRADS, it is possible to assign benign status to nodules with good reliability, thereby avoiding unnecessary FNAs. TIRADS is also helpful to detect most thyroid malignancies and to guide management decisions.