Efficacy of shear wave elastography in malignity assessment of thyroid nodules with atypia of undetermined significance and comparison with TI-RADS

Aim: The aim of this study is to investigate the effectiveness of shear wave elastography (SWE) in the differentiation of benign-malignant thyroid nodules diagnosed with atypia of undetermined significance (AUS) and to compare with the American College of Radiology (ACR)-thyroid imaging reporting and data system (TIRADS). Material and Methods: This monocentric study comprised 52 patients (9 males; 43 females) who were diagnosed with AUS by thyroid FNAB. All patients included in the study had gray scale ultrasound (US) and SWE images. The mean SWE value was calculated for each nodule, and TIRADS scores were determined based on the US. The obtained data were compared based on the histopathological result in patients who had undergone surgical treatment, and based on the cytology result in patients followed-up by FNAB, for the differentiation of benign and malignant nodules. Results: Nineteen patients were found to have malignant nodules and 33 had benign nodules. The mean SWE was 2.89 +/- 0.51 (2.30-3.92) and 2.91 +/- 0.48 (2.16- 3.79) in the malignant and benign cases, respectively. The results of independent T-tests between the two groups were insignificant (p=0.89). TIRADS 2-3 (total 29 patients) nodules were considered possibly benign, and TIRADS 4-5 (total 23 patients) possibly malign, the sensitivity, specificity, positive predictive and negative predictive value of TIRADS were identified 100%, 87.9%, 82.6% and 100%, respectively, when compared with the pathology results. Discussion: There was no significant difference in SWE values in the differentiation of malignant-benign thyroid nodules with AUS. However, the ACR-TIRADS criteria still maintain their importance.