Role of SpyGlass-DStm in the preoperative assessment of pancreatic intraductal papillary mucinous neoplasm involving the main pancreatic duct

It is often difficult to determine an adequate resection line during pancreatectomy for intraductal papillary mucinous neoplasm involving the main pancreatic duct during partial pancreatectomy. The aim of this study was to evaluate the usefulness of improved peroral pancreatoscopy using SpyGlass-DStm in the preoperative assessment of intraductal papillary mucinous neoplasm involving the main pancreatic duct. We collected and retrospectively analyzed clinicopathological data from seven consecutive patients who underwent preoperative assessment of intraductal papillary mucinous neoplasm involving the main duct using SpyGlass-DStm. Good imaging quality of the intraductal protruding lesion was obtained in all seven patients, and only one adverse event was noted wherein a patient had mild pancreatitis. Six patients underwent pancreatectomy. In one patient, masked-type concomitant pancreatic ductal adenocarcinoma and low-length dysplastic lesion was found near the surgical margin, which was not detected by preoperative imaging modalities including SpyGlass-DStm. The sensitivity of targeting biopsy during SpyGlass-DStm to diagnose high-grade dysplasia was 0%. SpyGlass-DStm can be safely performed in patients with intraductal papillary mucinous neoplasm involving the main duct, and has excellent visualization of the target lesion. However, challenges include poor diagnostic ability of targeting biopsy, and, therefore, intraoperative frozen section is still needed to obtain negative surgical margins.