Mo1484 The Utility of Endoscopic Ultrasound (EUS)-Fine Needle Aspiration (FNA) for the Diagnosis of Pancreatic Cystic Neuroendocrine Tumors (PCNETs): a Decade of Single Center Experience

performance of EUS guided core biopsy. The yield of the core biopsy as compared to FNA with onsite cytopathologists is not known. Methods: All patients referred for EUS guided biopsy were considered for EUS guided core biopsy followed by EUS guided FNA between February 2011 and November 2012 at the Houston Veterans’ Affairs Medical Center. Patients were excluded if they had cystic lesions, small lesions ( 1cm) or if interposing vascular structures prevented the intervention. Study patients were evaluated with two core biopsies using 22 gauge needles followed by FNA guided by a bedside cytopathologist. Results of the core biopsy were reported by a second pathologist at a later date. The yield (percent accurate diagnosis) was compared between the two groups. The agreement between the 2 approached was examined using the Kappa (K) statistic. The final diagnosis was defined using a conglomerate of surgical pathology, follow-up studies, and clinical course. Results: Twenty six patients were included in the final analysis, of which 96% were male and 61% were Caucasian. 69.2% had pancreatic lesions and 30.8% had other upper GI lesions including lymph nodes and subepithelial lesions. The mean number of passes was 3.2 for FNA, and the mean procedure time was 39.4 minutes. The final diagnosis was malignant in 92.3% and benign in 7.7%. Sensitivity and specificity were 83% and 100% respectively for FNA, and 71% and 100% respectively for core biopsy. Diagnostic accuracy was 84.6% for FNA and 73.1% for core biopsy. The two approaches yield was in agreement in 88.4% with a kappa statistic of 0.66 (95% CI: 0.33 0.99) indicating substantial agreement. Conclusions: The diagnostic yield of two passes with a 22 gauge core biopsy needle is comparable to the current gold standard of FNA with a bedside cytopathologist. Performance of two core biopsies could represent a time efficient and widely available alternative to FNA with a bedside cytopathologist.