Imaging pitfalls of pancreatic serous cystic neoplasm and its potential mimickers

Figure 8 A 74-year-old female with microcystic serous cystic neoplasm and intraductal papillary mucinous neoplasm. A: Magnetic resonance cholangiopancr -eatography (MRCP) shows a cystic mass (arrow) in the pancreatic head with mild upstream main pancreatic duct (MPD) dilatation; B: Follow-up MRCP 5 years after Figure 8A shows interval increase in size of the cystic lesion (arrow) with fusiform dilatation of the upstream MPD (arrowhaed) and cystic dilatation of multiple branch ducts. In retrospect, the cystic lesion in the pancreatic head appears microcystic without downstream MPD dilatation; C: The portal venous phase of an axial contrast enhanced-computed tomography shows an enhancing component (arrow) within the cystic lesion. Intraductal papillary mucinous neoplasm (IPMN) with solid component was suspected; D: Endoscopic retrograde pancreatography shows extrinsic compression of the MPD due to the cystic lesion in the pancreatic head (arrow) without cyst opacification, although fusiform dilatation of the upstream MPD (arrowhead) is demonstrated; E: Resected specimen shows the cystic mass in the pancreatic head consisting of microcysts. The enhancing component eventually represented fibrosis (arrow) within microcystic serous cystic neoplasm. In addition, the fusiform dilatation of the MPD turned out to be IPMN.