Thyroid FNA: Challenges and Opportunities

This special issue of Acta Cytologica focuses on new insights into thyroid fine needle aspiration (FNA). With the adoption of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC), the terminology obstacle has been overcome, but challenges remain, not the least of which is the application of the new terminology in practice. This issue points the way forward. TBSRTC is reviewed, with salient observations on the distinctions between categories. Data are presented on the histologic outcomes associated with the categories used in the United Kingdom, which allow for concordance with TBSRTC. A European consortium discusses the merits of implementing TBSRTC in the European community. Several papers dig deeply into the AUS/FLUS category, examining the variables that influence its rate and associated histologic outcome. Another study examines the common approach of waiting a few months before repeating an aspirate in patients whose prior thyroid FNA was inconclusive. New data is presented on the management of the patient with a repeatedly nondiagnostic thyroid FNA. This issue also includes descriptions of the mucin-producing tumors of the thyroid and papillary thyroid carcinomas that arise within a follicular adenoma. Several studies delve into the unfolding interface between cytology and molecular diagnostics. Finally, investigators examine high-resolution magic angle spinning proton magnetic resonance spectroscopy as an adjunct to cytology. As a group, these papers provide a snapshot of the state of the art as well as a glimpse into the future of thyroid FNA.