Direct peroral pancreatoscopy with a pediatric gastroscope for preoperative evaluation of the pancreatic duct in a patient with pancreatic intraductal papillary mucinous neoplasm.

Intraductal papillary mucinous neoplasms (IPMNs) are one of several types of mucinous tumors of the pancreas. They are uncommon ductal epithelial tumors, comprising approximately 10% to 15% of cystic pancreatic neoplasms. IPMNs can be classified into three types – main pancreatic duct IPMN (MD-IPMN), branch duct IPMN (BD-IPMN), and mixed – based on imaging studies (computed tomography or magnetic resonance imaging [MRI] with magnetic resonance cholangiopancreatography [MRCP]) and/or histological examination with endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) [1–5]. MD-IPMN is characterized by segmental or diffuse dilatation of the main pancreatic duct (MPD) of more than 5mm without other causes of obstruction [2]. A 70-year-old man was transferred to our department on an emergency basis with abdominal pain and fever up to 40°C that had lasted for 1 week. Computed tomography and MRI showed the pancreatic duct dilated to 40mm (●" Fig.1a). In the tail, the dilatation was to 60mm (●" Fig.1b). On endoscopic retrograde cholangiopancreatography (ERCP), mucinous material was seen to bulge out from the dilated ampulla of Vater – an uncommon but essentially pathognomonic sign of IPMN (●" Fig.2). After inspection of the MPD with an extraction balloon, mucinous material and pus were evacuated (●" Fig.3). We placed a 9-Fr nasopancreatic drain and withdrew aspirate for microbiological and cytological examination, which showed the presence of polymorphonuclear leukocytes, Gram-negative Pseudomonas aeruginosa, and Gram-positive Enterococcus faecalis. We tried to drain the pancreatic duct, but the mucinous material was too thick, and the procedure was ineffective. After we had stabilized the patient’s condition, on day 5 we performed a second endoscopic procedure – pancreatic sphincterotomy and peroral pancreatoscopy (POPS) – with a pediatric gastroscope. Polypoid structures were noted in the distal 30mm of the MPD (●" Fig.4a. ●" Fig.4b). At the level of the corpus and Fig.4 Peroral pancreatoscopy. a Polypoid structures in the pancreatic duct. b Polypoid structures in the pancreatic duct with pus. Fig.1 a Computed tomography shows extreme dilatation of the pancreatic duct to 40mm in a 70-year-old man presenting with abdominal pain and fever of 1 week’s duration. b In the tail, the duct is dilated to 60mm. Fig.3 After inspection of the MPD with an extraction balloon, mucinous material and pus are evacuated. Fig.2 Mucinous material bulging out from the dilated ampulla of Vater. Cases and Techniques Library (CTL) E598