Left hepatic trisectionectomy for hilar cholangiocarcinoma presenting with an aberrant biliary duct of segment 5: a case report

INTRODUCTION: Management of the biliary ducts during liver resection is one of the most important challenges for hepatobiliary surgeons. Here, we report the case of a left hepatic trisectionectomy for hilar cholangiocarcinoma with a rare aberrant biliary duct of segment 5, which, to the best of our knowledge, has never been reported in previous literature. CASE PRESENTATION: A 56-year-old Asian female initially presented with intrahepatic bile duct dilatation in the left lateral sector, left paramedian sector, and right paramedian sector. Simultaneous cholangiography from a percutaneous transhepatic biliary drainage tube in biliary duct of segment 8 and endoscopic nasobiliary drainage tube in biliary duct of segment 3 revealed drainage of the right lateral sectoral branch into the common hepatic duct and the aberrant drainage of segment 5 into the right lateral sectoral branch. The left hepatic duct, right paramedian sectoral duct, and the confluence of the right lateral sectoral duct were narrowed. Left hepatic trisectionectomy was successfully performed with careful dissection and division of the aberrant biliary duct of segment 5. CONCLUSION: For safe liver resection, it is important to perform a detailed anatomic evaluation of the intrahepatic ducts, both preoperatively and intraoperatively.