Postoperative hepatolithiasis in pancreaticobiliary maljunction and congenital biliary dilatation

Pancreaticobiliary maljunction (PBM) is a congenital malformation in which the pancreatic duct and the bile duct join outside of the duodenal wall. Due to the reciprocating flow of the pancreatic juices and bile, various complications can develop in the biliary tree system and the pancreas. Therefore, in cases with con- genital biliary dilatation, resection of the dilated extrahepatic biliary duct followed by hepaticojejunostomy (so-called flow diversion surgery) is considered to be a standard treatment. Despite being well-established as the standard treatment, com- plication characteristics of this disease, such as carcinogenesis and hepatolithiasis in the remnant bile duct, often develop long after the operation. In some cases, intrahepatic calculi are detected diffusely in both lobes. For the treatment of hepa-tolithiasis, complete removal of the calculi is recommended. However, even if the calculi are completely removed, it is not uncommon for patients to experience a recurrence. In postoperative hepatolithiasis, the percutaneous transhepatic and per- oral endoscopic approaches are considered the first choices of the treatment. In cases where endoscopic therapy has been unsuccessful or liver atrophy is observed during the course of treatment, surgery is required. Combining hepatectomy with endoscopic treatment may be effective for complete removal of the intrahepatic calculi. However, there is a need for development of a consensus on the indication, timing, and the selection of the optimal surgical procedure.