Can Endoscopic Ultrasound-Guided Fine Needle Aspiration Offer Clinical Benefit for Tumors of the Ampulla of Vater? -An Initial Study

Objective: No previous studies have described endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) only for intraampullarylesions of the papilla of Vater. We aimed to examine whether EUS-FNA can be used to diagnose such lesions.Methods: This study included a subset of 10 consecutive patients in whom EUS-FNA targeted the ampulla of Vater. All thepatients underwent biopsy and/or brushing cytology under endoscopic retrograde cholangiopancreatography (ERCP) prior to EUSFNA.The final diagnosis was based on pathological examinations of specimens obtained by surgical resection or clinical follow-upmore than 1 year in case of evidence of benign lesions.Results: Tissues from the ampulla of Vater could be obtained by EUS-FNA for all 10 patients. The final diagnosis was papillitis (n= 7) and intra-ampullary carcinoma (n = 3). Carcinoma of the ampulla of Vater showed neither exposure on the duodenal mucosalsurface nor invasion to the pancreas. The diagnostic accuracy of surface biopsy with duodenoscopy, and intra-ampullary biopsyand/or brush cytology with ERCP and/or intra-ampullary biopsy after endoscopic sphincterotomy (EST) in distinguishing betweenbenign and malignancy was 70%. The diagnostic accuracy of EUS-FNA was 100%. No complications associated with EUS-FNAwere encountered in this study.Conclusion: EUS-FNA for ampulla of Vater may be safely and accurately performed, and should be considered as a diagnosticmodality before EST.