Background
Intraductal papillary mucinous neoplasm (IPMN) is a premalignant epithelial tumor commonly arising from the pancreatic head with cystic appearance due to excessive tenacious mucin production. These cystic neoplasms can be divided into three types based on branch pattern: main duct (MD-IPMN), branch duct (BD-IPMN), and mixed-type IPMN. These tumors are found incidentally in asymptomatic patients, with a slightly higher percentage of tumors found in men, averaging age 65. CT findings characterize MD-IPMN as communicating with the main pancreatic duct, tortuous and dilated measuring > 5 mm in diameter. BD-IPMN are more variable cystic lesions that arise from branches of the main duct that communicate with main ductal system. Mixed-typed IPMN shares imaging features of both MD-IPMN and BD-IPMN. MR findings, particularly MRCP show T2-hyperintense cysts (unilocular or multicystic) with main duct communication or its branches. Fukuoka consensus guidelines recommend surveillance versus treatment based upon high-risk stigmata and clinical presentation. All types of IPMN have malignant potential, so knowledge of IPMN imaging patterns and presentations is required to avoid delay in diagnosis.
Educational Goals / Teaching Points
This educational exhibit will review typical and atypical cross-sectional imaging patterns of pancreatic IPMN with an emphasis on epidemiological, CT, MRI findings, and pathological correlation. 1. Review of epidemiology and clinical features of IPMN. 2. Identify relevant CT, MRI, and pathologic features of IPMN.
Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
MR findings, particularly MRCP, show T2-hyperintense cysts (unilocular or multicystic) with main duct communication or its branches. Microscopic pathology shows papillary projections with mucinous dilation of the duct.
Conclusion
All types of IPMN have malignant potential, so knowledge of IPMN imaging patterns and presentations is required to avoid delay in diagnosis.
