Intraductal papillary mucinous neoplasm (IPMN) is an exocrine neoplasm of the pancreas consisting of epithelial cells growing within the pancreatic ducts (main pancreatic duct or its major branches) and producing mucin. IPMN is a mucin-producing pancreatic cystic tumor. IPMN contains epithelial cells that can create papillary projections.