Pancreato-biliary maljunctions and congenital cystic dilatation of the bile ducts in adults

Pancreato-biliary maljunctions (PBM) in adults are defined by the presence of an abnormally long common pancreato-biliary duct (more than 15 mm long) formed outside the duodenal wall and/or by high amylase level in the bile. The high amylase level in the bile is the functional expression of a chroni c toxic reflux of pancreatic juices into the biliary tree. The presence of the PBM have two basic consequences: (i) formation of congenital cystic dil atations of the bile duct (CCBD) during embryogenesis and (ii) cancerous de generation of extrahepatic bile ducts including the gall bladder. CCBD are commonly found in Southeast of Asia and in Japan where more than two-thirds of the worldwide cases are reported. Women are more frequently touched. Th e main manifestations are pain, cholangitis and acute pancreatitis. Cancero us degeneration mainly due to chronic pancreatico-biliary reflux consecutiv e to the presence of PBM is the most serious complication of CCBD. Its glob al incidence is about 16% and increases by age and after cysto-digestive de rivations widely performed in the past. In 80% of the cases a cholangiocarc inoma involving the extrahepatic portion of the biliary tree including dila ted segments such as the gall bladder and/or cystic wall is found. The trea tment of choice of most common types of CCBD with PMD is complete excision of most of the sites where cancer may arise and should interrupt the pancre ato-biliary reflux. This treatment significantly reduces the incidence of b ile duct cancer to 0.7%. However, despite the absence of mortality, the ove rall morbidity rates reach from 20% to 40%. In the complete excision, the e ntire common bile duct from porta hepatis to the intrapancreatic portion of the choledochus and the gall bladder are resected. The bile continuity is assured by a hepatico-jejunal Y anastomosis. When there is no CCBD, the hig h risk of gall bladder cancer in the presence of a PBM justifies by itself a preventive cholecystectomy even if no biliary stone is present.