Pancreatobiliary fistula associated with intraductal papillary mucinous carcinoma accompanying obstructive jaundice: A case report.

INTRODUCTION:Intraductal papillary mucinous neoplasms (IPMNs) occasionally involve formation of fistulas with other adjacent organs. Pancreatobiliary fistulas associated with IPMNs are rare, but affected patients often develop obstructive jaundice and cholangitis. PRESENTATION OF CASE:A 79-year-old man was referred to our hospital for evaluation of abnormal biliary enzymes. Contrast-enhanced computed tomography and endoscopic retrograde cholangiopancreatography demonstrated multiple cystic lesions with septa in the pancreatic head and fistulas between the cystic lesions and common bile duct. The clinical diagnosis was pancreatobiliary fistula associated with a mixed-type IPMN and accompanying obstructive jaundice. The patient underwent subtotal stomach-preserving pancreaticoduodenectomy. The resected specimen showed fistulas between the cystic lesions and common bile duct. Histopathological examination showed that the main and branch ducts of the pancreatic head were dilated and filled with mucus. The epithelia of the pancreatic ducts revealed papillary proliferation and an invasive adenocarcinoma arising from an intraductal neoplasm. Immunohistochemistry examination showed CDX2- and MUC2-positive reactions. The final diagnosis was an intraductal papillary mucinous carcinoma of the intestinal-type. The patient remained disease-free for 9 months postoperatively. DISCUSSION:The causes of death in patients who have pancreatobiliary fistulas associated with IPMNs without resection are cholangitis or hepatic insufficiency. Nonoperative treatment is limited for cases with obstructive jaundice. It is necessary to prevent obstructive jaundice and cholangitis due to a large quantity of mucinous material. CONCLUSIONS:Surgical resection should be considered, if possible, in patients with pancreatobiliary fistulas associated with IPMNs. A better prognosis is expected with prevention of obstructive jaundice or cholangitis.