A Case of Hemosuccus Pancreaticus Due to the Rupture of a Pseudoaneurysm That Developed in an Intraductal Papillary Mucinous Neoplasm.

A 76-year-old woman with branch duct intraductal papillary mucinous neoplasm (IPMN) was admitted with epigastric pain and vomiting. She had received warfarin due to a history of deep vein thrombosis. A blood test showed decreased serum hemoglobin and elevated serum amylase. Contrast-enhanced computed tomography revealed acute pancreatitis and formation of a pseudoaneurysm in the IPMN. We suspected rupture of a pseudoaneurysm and performed trans-catheter angiography. Angiography showed extravasation from the posterior superior pancreaticoduodenal artery, and coil embolization was performed. It is important to be alert for the formation of pseudoaneurysm in patients with cystic neoplasms.