Hemosuccus pancreaticus from superior mesenteric artery pseudoaneurysm within perceived pancreatic mass.

Bleeding from the pancreatic duct is a rare source of gastrointestinal hemorrhage and is referred to as hemosuccus pancreaticus. Often a result of pseudoaneurysm formation from chronic pancreatitis, hemosuccus pancreaticus is a difficult diagnosis due to its peculiar clinical presentation. This is a case of a 51-year-old male with a history of chronic pancreatitis, who initially presented with a pancreatic mass found on CT scan. The mass was found to be inconclusive for malignancy on endoscopic ultrasound-guided fine needle aspiration. The patient subsequently was lost to follow-up and returned with melena and evidence of a superior mesenteric pseudoaneurysm in the previous mass on CT angiography. The pseudoaneurysm was successfully treated with endovascular embolization. Diagnosis of hemosuccus pancreaticus can be challenging due to the intermittent nature of hemorrhage and the variable clinical presentation-which initially appeared as a pancreatic neoplasm in our patient. Repeat imaging and angiography are invaluable for both the diagnosis and treatment of gastrointestinal bleeding from an unknown source in the setting of chronic pancreatitis.