Comparative analysis of United States and international thyroid fine-needle aspiration practices with an emphasis on molecular testing.

INTRODUCTION: Laboratory practices surrounding thyroid fine-needle aspiration (FNA) have shifted with the introduction of the Third Edition of The Bethesda System and the increasing utilization of molecular testing. The goal of this survey was to assess the current state of laboratory practices and ancillary molecular testing for thyroid FNA. MATERIAL AND METHODS: A 32 question online survey was developed by the Clinical Practice Committee of the American Society for Cytopathology (ASC) to assess thyroid FNA laboratory practices with an emphasis on ancillary molecular testing. The survey was distributed to the membership of the ASC and the International Academy of Cytology. Data was collected by SurveyMonkey, collated, and analyzed. RESULTS: A total of 220 responses were obtained with similar numbers of US and international participants. Utilization of rapid on-site evaluation (ROSE) for thyroid FNAs showed higher rates in the US, with nearly half of respondents evaluating adequacy on 76%-100% of FNAs, compared with 9% of international responses who reported similar rates. Molecular testing is offered by nearly all US-based respondents' laboratories whereas 38% of international respondents offered such testing. When molecular testing is performed, commercial assays designed to triage indeterminate results dominate US-based responses relative to international sites. CONCLUSIONS: Although there was good alignment between US and international responses around sample processing and reporting, distinct practice patterns surrounding ROSE and molecular testing were apparent, with notable opportunities to standardize or improve laboratory practices.