American Society of Cytopathology (ASC) study group recommendations for practicing ultrasound guided-fine needle aspiration (US-FNA).

Introduction: Ultrasound-guided fine needle aspiration (US-FNA) performed by cytopathologists is an expanding domain of effort; however, the clinical practice varies significantly across institutions and practitioners. To address this variability, a study group of the American Society of Cytopathology (ASC) Product Innovation Committee has initiated efforts to help bring consistency to US-FNA endeavors.

Materials and methods: In 2022, the ASC's Product Innovation Committee formed a study group as part of an initiative to standardize US-FNA practices. The group developed an online survey consisting of 32 questions related to US-FNA techniques and practices. The survey was distributed through the ASC and involved participation from several international cytopathology societies. The survey findings, combined with a literature review (spanning 50 articles over 36 years), on cytopathologist-performed US-FNA, served as the foundation for the group's recommendations.

Results: The literature review supports the contention that US-FNA performed by cytopathologists enhances diagnostic accuracy, specificity, and negative predictive value. The survey revealed significant variability in US-FNA activities (report in a separate manuscript entitled "Pathologist Performed Ultrasound Guided Fine Needle Aspiration: Current Status, Trends, and Insights from the American Society of Cytopathology Sponsored Survey"). Based on these findings, the ASC study group developed 10 key recommendations for cytopathologist-performed US-FNA regarding procedure, documentation, and quality control.

Conclusions: These recommendations are intended to provide a basis for evolving discussion among cytopathologists with the aim of creating consensus-driven practices in US-FNA.