Risk of malignancy according to sub-classification of the atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) category in the Bethesda system for reporting thyroid cytopathology

摘要

Objective: According to the Bethesda System for Reporting Thyroid Cytopathology, atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) is a heterogeneous category that includes cases with architectural and/or nuclear atypia insufficient to warrant classification as malignant neoplasms. The ambiguous and descriptive characteristics of the AUS/FLUS category mean that the impact of the present guidelines on repeat fine needle aspiration (FNA) is unclear. The present study reclassified AUS/FLUS cases into four sub-categories and then correlated them with histological or cytological follow-up data to clarify the risk of malignancy.