[Pancreatic serous cystadenoma resected after repeated biliary hemorrhage due to perforation into the common bile duct:a case report].

An 86-year-old woman was under follow-up at the Breast Surgery Department of our hospital for postoperative treatment for right breast cancer. During this period, a 22-mm cystic mass was identified in the pancreatic head. Its size gradually increased, and she was eventually referred to our department. Abdominal computed tomography revealed a cystic mass with a faintly enhanced septum in the pancreatic head as well as stenosis and dilation of the hepatic bile duct. Imaging suggested a serous cystic neoplasm (SCN);however, considering that the mass was growing and the patient had periodic liver dysfunction and abdominal pain, which were indicative of cholangitis, further assessment was required. The patient declined surgery, and endoscopic ultrasonography-guided tissue acquisition was performed for a definitive diagnosis of SCN. Cholangitis episodes were infrequent and resolved spontaneously, and the patient was monitored through follow-up. After 2 years, cholangitis occurred more frequently, and the SCN showed further growth. Moreover, the patient developed obstructive jaundice. The patient refused surgery again despite our recommendation. As a result, endoscopic retrograde cholangiopancreatography (ERCP) was performed, and a covered metallic stent was placed in the common bile duct to resolve bile duct stricture. Three years after diagnosis, the patient was hospitalized for recurrent orbital pain. ERCP revealed a filling defect in the stent and upper bile duct with proximal bile duct dilation. Balloon curettage resulted in the drainage of bile sludge and thrombus. The patient presented with cholangitis complicated by biliary hemorrhage, and an endoscopic nasobiliary drainage (ENBD) tube was placed to relieve obstruction caused by the thrombus. However, frequent bleeding from the ENBD tube suggested recurrent biliary hemorrhage, probably due to SCN, thereby requiring surgical intervention. At the request of the patient and her family, a pylorus-preserving pancreaticoduodenectomy was performed. The resected specimen was a large, 50-mm nodular lesion in the pancreatic head, extending from the pancreatic parenchyma to the bile duct, with stent compression and scarring from previous drainage. The lesion had a lobulated surface with cysts ranging from <1mm to 15mm, some of which exhibited hemorrhage. Surgical resection is the preferred treatment for symptomatic SCN. Although this patient eventually required surgery due to repeated biliary bleeding, the possibility that stent placement contributed to the hemorrhage suggests that surgical resection should remain the first-line treatment for SCN with obstructive jaundice.