Evalution of thyroid nodules with atypia of undetermined significance according to bethesda classification by elastography, scintigraphy and postoperative pathology results

According to Bethesda classification, the malignancy rate of thyroid nodules of atypia of undeterminated significance is %10-30. The aim of this study was to determine whether imaging methods are useful in the diagnosis of malignancy and to determine the value of malignancy in our center. Between December 2018 and November 2019, 35 thyroid nodule biopsies were diagnosed as Bethesda classification atypia of undeterminated significance/ follicular lesion of undeterminate significance (AUS/FLUS) preoperative performed ultrasound elastography and scintigraphy. All patients were operated and pathology results were examined. Seventeen (48.6%) of the patients included in the study were benign and 18 (51.4%) were malignant. Seventeen (94.4%) of the malignants were female and 1 (5.6%) was male. The median value of Emax was 35,140 kPa (6,556 -162,416) in benign patients in ultrasound elastography and the median value in malignant patients was 58,624 kPa (19,083 - 109,073). Ten patients (47.6%) with hypoactive nodules / nodules were found to be benign and 11 patients (52.4%) with malignant scintigraphy. Three patients (60%) with hyperactive nodules / benigns were found to be benign and 2 patients (40%) were malignant. Malignancy was detected in 2 patients with hyperactive and hypoactive nodules. In scintigraphy, 2 patients with diffuse increased involvement were benign, 1 patient with minimal activity and 1 patient with subacute thyroiditis were benign (P = 0.364) In the literature, there are publications supporting the high malignancy value in our study for the group named as AUS/FLUS, suggesting that this group should be more careful in the management of treatment. This group of patients should be carefully monitored and it should be remembered that direct surgery can be performed according to the clinical and ultrasound findings. Key words: atypia of undetermined significance, Bethesda classification, sonoelastography, scintigraphy