Evaluation of correlation between TIRADS [Thyroid Imaging Reporting and Data System] and FNAC of thyroid nodules.

Abstract

Purpose:To characterize the thyroid nodules according to grey scale ultrasonographic features using TIRADS scoring system into various categories. Then correlate the results with the cytopathological examination findings.Materials and Method: The present study was carried out in 100 patients in the tertiary care institute. Patients were enrolled prospectively for the study after obtaining informed consent. These patients were subjected to high resolution ultrasonography and fine needle aspiration as per pre-decided protocol. All thyroid nodules were characterized according to the consistency, margin, echogenicity, evidence of calcification and shape. Each nodule was classified into TIRADS categories [2,3,4A,4B and 5] based on ultrasound features. The ultrasound findings were correlated with FNAC and data was analyzed statistically.Results: The sensitivity and specificity for irregular contours were 93.33 % and 94.12%, for taller than wide shape were 20.0% and 100%, for microcalcification were 53.33% and 94.29%, for marked hypoechogenicity were 73.33% and 60.89% and for solid consistency were 53.33% and 62.86%. The risk of malignancy was found to increase from TIRADS3 to TIRADS5 in the study. All the cases [100%] of TIRADS 5 turned out to be malignant on cytopathology.Conclusion:Sonographic features like irregular margins, marked hypoechogenicity, microcalcification and taller-than-wider shape were all associated with increased risk of malignancy. The risk of malignancy was found to increase from TIRADS 3 to TIRADS 5 when different TIRADS categories were confronted with results of pathology and risk of malignancy was calculated.