Tu1303 Risk of Adenocarcinoma in Resected Intraductal Papillary Mucinous Neoplasm (IPMN) With Involvement of the Main Pancreatic Duct (MD)

Background & Aims: Endoscopic ultrasound (EUS) is often used as the gold standard to diagnose chronic pancreatitis (CP) despite concerns about its intra-operator reliability and validity. We sought to determine the benefit of repeat EUS in patients suspected of having CP but having an equivocal or negative initial EUS exam for CP. Methods: Patients who underwent at least two EUS exams at our medical center to evaluate for CP from 20012012 were identified. Demographic, procedural and etiologic factors were abstracted via chart review. Specifically, EUS minimal standard criteria (MST) for CP (hyperechoic foci, hyperechoic strands, lobularity, cysts, ectatic duct, hyperechoic ductal wall, dilated side branches, ductal stones, ductal dilation) were abstracted for all exams. Diagnosis of CP was based on physician impression following each EUS. Results: Between the first and second EUS exams, the number of patients diagnosed with CP increased from 49% to 76% (p<0.01). Additionally, the number of patients with an indeterminate diagnosis after the first exam decreased significantly after the second exam (41% vs 21%, p<0.01). The presence of hyperechoic foci increased on the second exam (50% vs. 68%, p=0.04), but no other parenchymal or duct features were found to reliably increase. On subgroup analysis, significant increases in hyperechoic foci identified on repeat EUS were found in women (43% vs 67%, p=0.03), patients under the age of 50 (47% vs 74%, p<0.02) and patients in whom recurrent acute pancreatitis is the etiology of their CP (18% vs 73%, p=0.03). Conclusions: Serial EUS exams are valuable in patients with indeterminate prior EUS exams in whom the diagnosis of CP is not secure. In particular, women and those <50 years old appear to benefit the most from serial evaluation.