Use of Recommendations of ASC Task Force During ROSE Validation with Emphasis on Importance of Including Case Mix for EUS and EBUS FNA Specimens

Summary: Introduction: The American Society of Cytopathology (ASC) recommends 60 total cases corresponding to the clinical setting be evaluated for ROSE telecytology WSI validation. EUS/EBUS FNA specimens represent the most diagnostically complex, invasively collected ROSE specimens (with potential for GI and respiratory tract contamination) that carry potential repercussions on repeat procedures. EUS/EBUS FNA specimens' differential diagnoses includes but is not limited to carcinoma, lymphoma, and neuroendocrine tumor that requires different ancillary testing specimens during ROSE for the correct diagnosis and adequacy determination. The retrospective validation case mix should include EUS/EBUS FNA specimens with these different categories to tremendously elevate the quality of care for primary diagnosis and staging for the deep-seated tumors where the role of telecytology is most critical to allow subspecialty care even in remote locations, though the literature is sparse on this inclusion. Materials and Methods: From the published guidelines, at a regional Veteran Affairs Medical Center (VAMC), a case mix of 60 FNA cases with an air-dried Diff Quik stained slide was evaluated on the Philips SG300 (Amsterdam, Netherlands) platform with addition of 10-20 cases from EUS/EBUS FNA for validation experience across the diagnostic spectrum. Results: There were 60 FNA cases including 17 EUS FNA cases, 3 EBUS FNA cases, 26 thyroid cases, 10 head and neck cases, and 4 other site cases. This ROSE telecytology case mix was validated successfully following published guidelines. Conclusions: In clinical settings with EUS/EBUS ROSE FNA cases, we recommend including 10-20 of these critical cases to prevent repercussions from the need for repeat FNA for diagnosis or ancillary samples due to lack of experience during validation.