Abstract
Thyroid nodules are a common finding in the adult population. Fine-needle aspiration biopsy (FNAB), when required, has an important role in the assessment of a thyroid nodule by assisting the triage of patients to surgery or surveillance. However, FNABs which are classified in the Bethesda category 3 (atypia of undetermined significance (AUS) or follicular lesion of undetermined significance (FLUS)) are difficult to manage because of the wide spectrum of cytopathologic findings in this category. While the Bethesda System for Reporting Thyroid Cytopathology recommends repeat FNAB for category 3, recent studies recommend molecular testing, if available. And also, surveillance or surgery is recommended especially if repeat FNAB cytology and/or molecular testing is not performed or inconclusive. In conclusion, unlike other categories in Bethesda classification, management of the AUS/FLUS category is still controversial.
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Ali Koç, M., Demirer, S., Kocaay, A.F. (2019). A Gray Zone in Thyroid Fine-Needle Aspiration Cytology: AUS-FLUS. In: Özülker, T., Adaş, M., Günay, S. (eds) Thyroid and Parathyroid Diseases. Springer, Cham. https://doi.org/10.1007/978-3-319-78476-2_18
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DOI: https://doi.org/10.1007/978-3-319-78476-2_18
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