What IPMN Represents
IPMN is a distinct pancreatic neoplasm characterized by papillary proliferation of mucin-producing epithelial cells within dilated pancreatic ducts. 3, 4
Key Defining Features
Intraductal growth pattern: The neoplasm grows within the pancreatic duct system rather than forming a separate mass outside the ducts 4
Papillary architecture: Friable papillary projections develop within the mucin-filled, dilated ducts 2
Mucin production: Copious mucin secretion is a hallmark feature, leading to characteristic ductal dilation 5, 6
Cystic dilatation: The excessive mucin production causes visible cystic expansion of the main pancreatic duct and/or branch ducts 5, 7
Clinical Significance
IPMNs represent precursor lesions with malignant potential, exhibiting a spectrum from benign adenoma to invasive carcinoma. 5, 6 The American College of Surgeons emphasizes that these neoplasms show an adenoma-carcinoma sequence with varying degrees of dysplasia 2
Approximately 40% of IPMNs develop invasive carcinoma, which critically worsens prognosis. 4 However, when completely resected before invasion occurs, the 5-year survival approaches 100% 6