Prevalence of Atypia of Undetermined Significance (AUS) in Thyroid Fine Needle Aspirations; A Three-Year Single Institution Study

Document Type

Conference Proceeding

Publication Date

3-1-2024

Publication Title

Lab Invest

Abstract

Background: The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) now subclassifies AUS in to AUS -nuclear and AUS - other subcategories. There is limited data available on AUS rate and it varies among different laboratories from 1% to over 20%. TBSRTC provisional goal of limiting the rate of AUS to 7% was revised to 10% in second edition. Other quality indicators to limit the diagnostic rate of AUS also includes AUS/malignant ratio of less than three. Our objective is to determine the rate of AUS and AUS/malignant ratio. Design: A retrospective review of three-year thyroid FNAs from our center during the period of January 2020 to January 2023 was performed. We selected all cases with diagnoses of AUS/FLUS and all cases positive for any types of thyroid carcinoma. The AUS rate and AUS/malignant ratios are calculated. Results: We retrieved 3645 cases; 504 cases were diagnosed as AUS/FLUS; 97 cases were diagnosed as malignant. The overall three-year AUS rate is 13.8% and AUS/malignant is 5.1% (see table 1). Conclusions: We reported our three-year AUS rate and AUS/malignant ratio. Our results are slightly higher than TBSRTC recommended 10% and shows increasing trend. Continuous monitoring of AUS rate and AUS/malignant ratio are useful laboratory quality measures to limit AUS interpretations.

Volume

104

Issue

3

First Page

S380

Last Page

S381

Find It @ Sladen

Share

COinS