Arteriovenous malformation in pancreas mimicking hypervascular tumor.

Arteriovenous malformation (AVM) is defined as a disease that causes blood flow abnormality due to anastomoses of the arteries and veins. AVM can occur in any gastrointestinal tract, but pancreatic AVM (P-AVM) is very rare. Previous reports demonstrated that contrast-enhanced CT (CECT) typically showed abnormal vascular network in pancreas. We present a 58-year old man with a history of acute pancreatitis. He was referred to our hospital for examination of pancreatic mass. CECT showed a round-shaped hypervascular lesion with a diameter of 8 mm in the head of the pancreas. Selective angiography showed vascular network and early visualization of superior mesenteric vein. We finally diagnosed this case as P-AVM. He underwent duodenum preserving pancreatic head resection. Histological findings confirmed the preoperative diagnosis of P-AVM.