The features of early intraductal papillary mucinous neoplasms and postoperative sutures under high-definition pancreatoscopy and EUS (with video).

A 65-year-old man underwent distal pancreatectomy for the suspected IPMNs in the pancreas tail 2 years ago. The postoperative pathology result turned out to be IPMN with obvious moderate dysplasia lesion in the main pancreatic duct (PD), and the excision site was lesion-free. This patient was followed up with magnetic resonance cholangiopancreatography once every 6 months, and the remnant PD grew wider gradually [Figure 1]. Moreover, an obvious hyperechoic mass was found in the dilated PD close to the excision site under the latest EUS examination [Figure 2A].Figure 1: Postoperative MRCP showed that the remnant PD broadened obviously. MRCP, magnetic resonance cholangiopancreatography; PD, pancreatic duct.Figure 2: An obvious hyperechoic mass was found in the dilated PD close to the excision site under EUS (A), and some postoperative sutures were found in the same location under pancreatoscopy unexpectedly (B). PD, pancreatic duct.Therefore, we performed endoscopic retrograde cholangiopancreatography and high-definition pancreatoscopy inspection (eyeMAX, 9F; Micro-Tech, Nanjing, China) for the patient. First, typical fish-eye sign was found on the main papilla [Figure 3], and pancreatography confirmed the obviously dilated proximal PD. Subsequently, the pancreatoscopy was inserted into the PD, and some postoperative sutures, which presented a hyperechoic mass under EUS, were found in the excision site of distal PD unexpectedly [Figure 2B]. Moreover, a lot of white translucent papillary lesions were found growing from the wall of PD or floating in the pancreatic liquid [Figure 4]. Finally, biopsy was conducted under pancreatoscopy, and the pathology result turned out to be papillary tissue covered with mucoid epithelium [Figure 5], consistent with IPMN.Figure 3: Typical fish-eye sign was found on the main papilla under duodenoscope.Figure 4: A lot of white translucent papillary lesions were found growing from the wall of PD (A) or floating in the pancreatic liquid (B). PD, pancreatic duct.Figure 5: The pathology result turned out to be papillary tissue covered with mucoid epithelium, consistent with IPMN. IPMN, intraductal papillary mucinous neoplasm.Previous studies have confirmed that pancreatoscopy was helpful for the diagnosis of suspected IPMN.[1,2] However, the appearance of early IPMN under pancreatoscopy was not known to endoscopists. This study presented the features of early IPMN using a high-definition pancreatoscopy. On the other hand, this case also confirmed that early IPMN might not present obvious signs under EUS. Moreover, a hyperechoic mass in the PD under EUS turned out to be postoperative sutures under direct vision. Therefore, we presented this rare case to provide reference for endoscopists in the field of endoscopic retrograde cholangiopancreatography and EUS.