Mixed-type intraductal papillary mucinous neoplasm in a patient with pancreas divisum: pancreatoscopy through the Santorini duct with direct intraductal biopsy

Abstract

View Large Image Figure ViewerDownload Hi-res image Download (PPT)A 72-year-old man with abdominal pain, hyperamylasemia/lipasemia, and dilatated main pancreatic duct shown by CT underwent MRCP (A, top left) that suggested a mixed-type intraductal papillary mucinous neoplasm (IPMN) with ectasia of multiple branch pancreatic ducts (A, top right) and of the entire dorsal duct (Santorini, 8 mm), draining the dorsal part of the pancreas through minor papilla (A, bottom left), with an incomplete ventral duct (Wirsung, A, bottom right), consistent with pancreas divisum (PD). EUS showed echoic material inside branch duct dilatations (B). Endoscopy showed a typical “fish-mouth” appearance of the minor papilla, draining mucus (C, top left). Pancreatography through the minor papilla confirmed dilatation of the Santorini duct (C, top right). Peroral pancreatoscopy through the minor papilla, with use of the SpyGlass system (Boston Scientific, Boston, Mass, USA), confirmed diffuse dorsal duct dilatation with mucinous material and papillary projections from the intraductal epithelium (C, bottom left). Histologic analysis of targeted intraductal biopsy specimens obtained with SpyBite forceps (Boston Scientific) (C, bottom right) demonstrated a mucin-producing papillary neoplasm with severely atypical cells, suggestive of malignancy (D, left: H&E, orig. mag. ×25). The patient underwent total pancreatectomy (D, middle); final pathologic examination demonstrated malignant IPMN (D, right: H&E, orig. mag. ×50). Patients with PD are at risk for the development of pancreaticobiliary tumors, including IPMN. In patients with PD and dorsal duct dilatation, the coexistence of main-duct IPMN should be considered. Our advice is to perform dorsal duct pancreatoscopy and direct biopsies to reach a final diagnosis. All authors disclosed no financial relationships. Commentary In 2020, most readers of Gastrointestinal Endoscopy should be familiar with the clinical manifestations of intraductal papillary mucinous tumors. Peroral pancreatoscopy with the use of ERCP has been performed in this setting for many years, both to confirm the diagnosis by imaging and perform biopsies and to quantify the extent of disease. Peroral pancreatoscopy can thus help to determine whether a patient would benefit most from a distal pancreatectomy, a pancreaticoduodenectomy, or a total pancreatectomy (as this patient underwent). This patient had pancreas divisum, which allowed peroral pancreatoscopy to be performed through the minor papilla, making the case even more interesting. It should be recognized that peroral pancreatoscopy carries the risk of causing post-ERCP pancreatitis, even in experienced hands, and appropriate steps should be taken to minimize the risk to the patient. Douglas G. Adler, MD, FASGE, GIE Senior Associate Editor, University of Utah School of Medicine, Salt Lake City, Utah Mohamed O. Othman, MD, Associate Editor for Focal Points