Superior Mesenteric Vein Pseudoaneurysm Presenting as a Pancreatic Mass: 1060

Introduction: A 67-year-old man with a past history of hypertension and long-standing alcohol abuse was admitted for shortness of breath secondary to new-onset heart failure. His hospital course was complicated by hypertensive emergency and delirium tremens requiring intubation and midazolam drip. An ultrasound of the abdomen was performed to evaluate for cirrhosis and revealed a questionable mass in the uncinate process of the pancreas and a dilated pancreatic duct to 6 mm in the head. At this time GI was consulted for further evaluation. A palpable epigastric mass was noted on physical exam and labs revealed a low albumin, 2.5 g/dL. Liver function tests, amylase, lipase, and coagulation studies were otherwise normal. CT scan of the abdomen demonstrated a 2.8 x 3.2 x 2.8 cm enhancing lesion concerning for a tumor in the area of the pancreatic head and superior mesenteric vein (SMV). Endoscopic ultrasound (EUS) was performed and revealed a dilated SMV to 25 x 21 mm with pseudoaneurysm formation. The EUS also revealed multiple criteria to establish a diagnosis of chronic pancreatitis. Arteriogram was performed and did not show an arteriovenous malformation. The patient was diagnosed with a SMV pseudoaneurysm and discharged in stable condition, remaining asymptomatic upon outpatient follow-up. Pseudoaneurysms are a rare complication of chronic pancreatitis. It is theorized that pancreatic enzymes may erode the peripancreatic vessels and result in the formation of a pseudoaneurysm. Vessels commonly affected include the splenic, hepatic, gastroduodenal, and cystic arteries. Eighty-nine percent of patients with a pseudoaneurysm complain of abdominal pain and complications include thrombosis and bleeding. When bleeding occurs, surgery is complicated and is associated with a high morbidity and mortality. Conservative management with serial abdominal imaging, usually ultrasound, is generally recommended, as 94% of pseudoaneurysms remain stable and a much smaller percentage regress. We found no published cases of SMV pseudoaneurysms mimicking pancreatic cancer. We present a unique case of an asymptomatic patient with SMV pseudoaneurysm from chronic alcoholic pancreatitis masquerading as pancreatic cancer. Vascular pseudoaneurysms must be considered in the setting of chronic pancreatitis, especially when a mass-like lesion is discovered.Figure 1