Characterized as Atypia of Undetermined Significance or Follicular Lesion of Undetermined Significance and Correlation With Ultrasound Features and BRAFV600E Mutation Analysis

ules with a previous FNAB result of AUS/ FLUS, respectively [1, 2]. The risk of malig-nancy seems to be diverse, and there is dis-agreement among physicians and institutions about the optimal management for AUS/ FLUS thyroid nodules with regard to clini-cal observation, repeat FNAB, core needle biopsy, or surgery [4–16]. Thus, 70–84 % of patients with indeterminate thyroid nodules undergo surgical procedures and hormone replacement therapy despite the cost and in-convenience [13]. To overcome this limitation, several stud-ies have investigated clinical risk factors or ultrasound findings and revealed that men older than 40 years and a nodule diameter of 2 cm or larger are significantly associated with malignancy in thyroid nodules with in-determinate cytologic results [9, 10]