Investigating branch duct intraductal papillary mucinous neoplasms: Is large-volume lavage cytology the wave of the future?

摘要

Like autoimmune pancreatitis, there was a time when intraductal papillary mucinous neoplasm (IPMN) was considered a "Japanese disease"; little of it was seen in the West. But ever since 4 cases were described by Ohashi et al in 1982, reports of this odd pancreatic tumor have increased worldwide. In the early days of ERCP, a diffusely dilated main pancreatic duct (PD) was assumed to be the result of obstruction at the level of the ampulla, and a dilated side branch was usually ignored or dismissed as a manifestation of chronic pancreatitis. We know better now: IPMNs are tumors of the pancreas arising from the ductal epithelium that range from benign to malignant, with a spectrum of dysplasia along the way. IPMNs are broadly divided into main duct and branch duct varieties, with infrequent mixed types that combine features of both. The classic main duct IPMN generates a large amount of mucus that causes the duodenal papilla to gape open, an almost pathognomonic appearance ("almost," because rare, mucus-secreting tumors of the bile duct can produce the same appearance).