Choledochal cyst,pancreatobiliary malunion,and cancer

A review of the clinical features of biliary cancer with choledochal cyst and pancreatobiliary malunion is presented, together with a recent case report. Biliary cancer develops in about 25% of patients with choledochal cyst and pancreatobiliary malunion, and usually occurs in younger patients (usually those in their 40s) than does biliary carcinoma in the general population. The risk of malignancy in the retained cyst with internal drainage is higher than that in the primary cyst. Early excision of the retained cyst should be performed as quickly as possible, even if the patient is symptomless. Some bile acid fractions and refluxed pancreatic enzymes in bile are possibly responsible for carcinogenesis. Carcinoma generally develops in the extrahepatic bile duct and gallbladder, and rarely in the intrahepatic bile duct. In cystic dilatation, cancer usually occurs in the common bile duct, while in diffuse or non-dilated type, it develops in the gallbladder. Multicentric carcinomas develop in the bile duct either synchronously or metachronously. The prognosis of biliary cancer is usually dismal. However, aggressive procedures are now gaining better results than conventional approaches. The procedure of choice for choledochal cyst or malunion is to prevent the development of cancer by performing an early excision. Removal of the entire extrahepatic bile duct is necessary, even in patients with malunion and no biliary dilatation. Carcinoma rarely arises in the intrahepatic bile duct after excisional surgery, probably due to the long-standing stricture of the bile duct. Capacious anastomosis and/or ductoplasty is essential. Carcinoma may also develop in the remnant bile duct. Excision of the distal duct extending into the pancreas is also necessary.