Surgical treatment of hilar cholangiocarcinoma Currently, the most effective treatment for extrahepatic cholangiocarcinoma is still surgical resection, but the biological behavior of cholangiocarcinoma determines its clinical characteristics of low resection rate. In particular, because of its extrahepatic bile duct and special location, cholangiocarcinoma of the hilar region is often at an advanced stage once diagnosed, so surgical resection is more difficult. The literature reports that about 5% to 50% of bile duct cancers can be surgically resected, with an average of 20%. Preoperative preparation: Because of the wide scope of resection for cholangiocarcinoma of the porta hepatis, in many cases, simultaneous lobectomy is required, and patients often have severe jaundice, malnutrition and immune deficiency, and patients with cholangiocarcinoma are generally older, so good preoperative preparation is very important. Liver preservation therapy: For patients with long time and severe jaundice, especially for those who may undergo extensive hepatic, biliary and pancreatic resection, preoperative assessment of liver function and liver preservation therapy are very important. Some lesions with local conditions that are still resectable are overwhelmed by the inadequate reserve state of the liver and the opportunity for surgery is lost. Patients with adequate preoperative preparation, some with complex, long and extensive surgeries, can still pass through the perioperative period smoothly. Preoperative preparation is a prerequisite to ensure the safety of surgical performance and to reduce complications and morbidity and mortality rates. The following conditions indicate poor liver function and contraindication to combined liver surgery, especially contraindication to hepatic or pancreatic resection of more than half of the liver: A. Total serum bilirubin above 256 μmol/L; B. Human albumin below 35 g/L; C. Prothrombin activity below 60%, time prolongation greater than 6s, and difficult to correct after 1 week of vitamin K injection. ④ Indocyanine green contour test (indigocyanogreentest) was abnormal. Preoperative CT was applied to measure the volume of the whole liver and the volume of the liver to be resected, and calculate the volume of the preserved liver, which can help to assess liver function in the proposed radical resection of enlarged hilar cholangiocarcinoma. In addition, glucose tolerance test and prealbumin (preprotein) measurement are helpful for estimation of liver function of patients. Preoperative hepatoprotective therapy is necessary, but if biliary obstruction cannot be released, relying on pharmacological hepatoprotective therapy alone is not effective. Currently, commonly used drugs aim to lower transaminases, replenish energy, and increase nutrition. Hypertonic glucose, human albumin, branched-chain amino acids, glucuronolactone (glucuronide), pantodecalinone (coenzyme Q10), vitamin K, and high-dose vitamin C are commonly used. Preoperative hepatoprotective therapy should also take care to avoid drugs that are damaging to the liver. Judging the possibility of lesion resection: it is an important part of preoperative preparation for hilar cholangiocarcinoma, which is helpful to formulate a feasible surgical plan and reduce blindness. It is mainly based on imaging examinations, but it is very difficult to achieve accurate judgment before surgery, and sometimes it is necessary to confirm after dissection, so the mutual complement of multiple examination modalities should be emphasized. Judgment of the possibility of surgical resection of bile duct cancer can generally be initially estimated based on preoperative PTC, CT and SCAG, but finally, it still needs to rely on intraoperative views and intraoperative ultrasound, and intraoperative transhepatic percutaneous cholangiography can also be used for judgment.