A case of cancer of the major duodenal papilla that developed 4 years after intraductal papillary mucinous neoplasm of the main pancreatic duct

An 87-year-old woman was found to have dilation of the main pancreatic duct on endoscopic therapy for choledocholithiasic cholangitis and a small protrusion in the main pancreatic duct on peroral pancreatoscopy. We made a diagnosis of benign main-duct intraductal papillary mucinous neoplasm (IPMN) and decided to follow up using abdominal ultrasonography. After 4 years, the patient returned and was found to have obstructive jaundice and increased diameter of the main pancreatic duct. Abdominal computed tomography revealed ring enhancement around the major duodenal papilla and endoscopic retrograde cholangiopancreatography showed enlargement of the major duodenal papilla; thus, cancer of the major duodenal papilla was diagnosed. Endoscopic biliary stenting using 10-Fr DLS was performed. She was discharged under the policy of best supportive care due to old age. IPMN in the main pancreatic duct is associated with other organ cancer in 20-30% of cases; routine follow-up examination is crucial.