Correlation of ACR-TIRADS(thyroid imaging, reporting and data system)-2017 and cytological/ Histopathological (HPE) findings in evaluation of thyroid nodules

Abstract

Background: Thyroid nodules are one of the most common lesions in the daily practice of a radiologist. The frequency of thyroid nodules is also increasing with time as thyroid disorders are rising. As the Ultrasound technology is advancing, so is the detection of thyroid lesions, even if they are as small as few millimeters in size. While fine needle aspiration cytology(FNAC) is the standard procedure for thyroid nodules diagnosis; it involves risks and unnecessary costs. But a benefit that we cannot ignore is that ultrasound guided aspiration reduces the number of unnecessary thyroid surgeries. While individual characteristics which increase the suspiciousness of malignancy, have been studied repeatedly but are inconclusive, we therefore need a comprehensive system of stratifying thyroid nodules and characterizing them with confidence so that we can reduce the number of needless painful aspiration and biopsy procedures. But only 3-7% nodules have specific characteristics of malignancy. TheACR-TIRADS (American College of Radiology- Thyroid imaging reporting and data system)2017 is score-based and assigns points according to the composition, echogenicity, shape, margins, and echogenic foci of thyroid nodules on ultrasound, which makes it easy and reliable. Method: B-mode sonography and Doppler evaluation of 104 thyroid lesions was performed on Aloka Arietta S-60 equipped with a 5-13 MHz high frequency linear array transducer.Results: Individual characteristics like solid composition (P value0.001), hypo-echogenicity (P value <0.0001), irregular borders, taller than wide shape and micro-calcifications (P value 0.067) were highly predictive of malignancy.Conclusion: Our study shows that the ACR-TIRADS 2017 is a good predictor of malignancy with just 1 false positive in the TR-5 category and 0 false negatives in the TR-1 or 2 categories. Also, it can help in stratifying patients according to their size so that timely management of critical cases is possible and unnecessary invasive procedures can be avoided for a section of patients who are advised follow up.