Due to the unique anatomical and biological characteristics of hilar cholangiocarcinoma, most patients are already in the middle to late stage when diagnosed, and the overall treatment effect is not satisfactory. Radical resection is an extremely complex and difficult operation, involving a series of complex issues, including determination of the extent of lesion involvement and resection, treatment of the invaded vessels in the hepatic portal area, reconstruction and reconstruction of the bile ducts in the residual liver section, and contouring of the regional lymph nodes and nerve plexus. It is clinically proven that the involvement of hepatoduodenal ligament, hepatic artery, portal vein, lymph nodes and nerve fibers is often the main cause of tumor recurrence and affects the outcome of radical surgery, among which the contouring scope of lymph and nerve plexus is particularly worthy of attention and discussion, but no unanimous consensus has been reached yet. Lymph node metastasis is one of the major metastases of hilar cholangiocarcinoma, and previous studies have shown that more than 30% of hilar cholangiocarcinoma has lymph node metastasis at the time of surgery, and the incidence of lymph node metastasis is often underestimated by routine pathological testing. The incidence of lymph node metastasis is directly proportional to the depth of local infiltration of cholangiocarcinoma, and the rate of lymph node metastasis in stage pT3 is significantly higher than that in stage pT2 tumors according to TNM staging criteria. According to the American Cancer Society (AJCC) staging criteria for cholangiocarcinoma (6th edition, 2002), regional lymph nodes include the cystic duct, paracolic duct, hilar region, paraportal vein, paraduodenal, posterior pancreatic head, celiac trunk and superior mesenteric lymph nodes; the para-abdominal aortic lymph nodes are non-regional lymph nodes. The AJCC/UICC staging criteria for cholangiocarcinoma, 7th edition (2010), also classifies the celiac trunk and superior mesenteric lymph nodes as non-regional lymph nodes, and stipulates that in order to obtain accurate TNM staging of tumors, at least three lymph nodes should be taken for pathological examination during surgery for hilar cholangiocarcinoma to clarify the lymphatic metastasis. Japanese scholars have found that the paracolic lymph node is the most critical station in the lymphatic metastasis pathway in patients with hilar cholangiocarcinoma, and the main lymphatic metastasis pathway is from this lymph node to the paraportal vein, paracolic artery and peripancreatic head lymph nodes, and then to the parietal aortic lymph node. In addition, the tumor may also metastasize directly to the para-aortic lymph nodes via the lymph nodes in the hepatoduodenal ligament; the involvement rate of the lymph nodes in the celiac trunk and superior mesenteric artery was even lower than that of the para-aortic lymph nodes; and no jumping metastasis was found in hilar cholangiocarcinoma. Therefore, according to the above metastasis pattern, they divided the lymph node metastasis of hilar cholangiocarcinoma into three stations (JSBS staging): N1, N2 and N3. N1: hepatoduodenal ligament lymph nodes (12 groups), which were divided into paracolic (12b group), posterior portal vein (12p group), and paracolic intrinsic hepatic artery (12a group) according to the surrounding relationship. n2: posterior pancreatic (13 groups) and along the paracolic common hepatic artery lymph nodes (group 8). n3: abdominal aorta (group 16), celiac trunk (group 9), superior mesenteric (group 14) or prepancreatic (group 17) and posterior inferior pancreatic (group 13b) lymph nodes. It is generally accepted that to achieve R0 resection a standardized regional lymph node dissection must be performed, which should include both station N1 and station N2 lymph nodes. Among them, “skeletonization” of hepatoduodenal ligament is the focus of radical surgery, and the scope is from the hepatic hilum to the superior margin of the pancreas, requiring preservation of hepatic artery and portal vein within the hepatoduodenal ligament, and emphasizing whole block resection including extrahepatic bile ducts, nerves, lymph nodes, fat, fibrous tissue and other tissues that may be invaded by the tumor. It is well recognized that patients with lymph node metastasis at station N1 can still achieve R0 resection after debulking, but some scholars still question whether R0 resection can be achieved after debulking lymph node metastasis at station N2. There is a consensus that if negative surgical margins can be achieved, lymph node contouring should not be abandoned because the regional lymph nodes have metastasized, and local lymph node metastasis should not be considered a contraindication to surgery. Since the prognosis of patients with definite abdominal aortic lymph node metastases is poor even with extended debulking, the 16 groups of lymph nodes are mainly used to determine the prognosis, i.e., the biopsy is more significant than the contouring itself. Therefore, whether it is necessary to perform an extensive clearance of 16 groups of lymph nodes in the strict sense or including other N3 lymph nodes should be treated carefully and individually according to the patient’s specific situation. In addition to direct infiltration metastasis, implant metastasis, lymphovascular and hematologic metastasis, perineural infiltration plays an important role in the progression of the disease as an independent mode of tumor cell metastasis and is an important factor affecting the postoperative survival of patients with biliary cholangiocarcinoma, with a higher incidence than lymph node metastasis, ranging from 76.3% to 100%. Tumor cells often spread around the nerve tissue and can grow in a “jumping” manner inside the nerve fibers and develop distant metastasis, which is one of the important reasons for local recurrence after surgery. The incidence of perineural metastasis is not related to the location of cholangiocarcinoma, tumor size, or the presence of lymph node metastasis, but to the pathological staging of the tumor, which is significantly higher in the nodal infiltrative type and infiltrative type than in the nodal carcinoma and papillary carcinoma. Cancer cells may infiltrate through the perineural gap around the bile duct in the proximal or distal direction. Cancer metastasis in the connective tissue of the hepatoduodenal ligament may be achieved by cancer cells spreading through the perineural gap. Academician Huang believes that metastasis of hepatoportal bile duct cancer through the neural route is more serious than the vascular and lymphatic routes. The nerve plexus on the hepatoduodenal ligament is mostly around the hepatic artery and close to the portal vein. Therefore, when completely removing the cancerous tissues, especially when “skeletonizing” the Glisson sheath where the hepatoduodenal ligament and the first and second bile ducts are located, the nerve fibers between the bile ducts and the hepatic artery and portal vein should be carefully peeled off and removed in whole pieces close to the outer membrane of the vessels. However, care should be taken not to damage the outer membrane of the artery. In conclusion, due to the complexity of hepatoportal cholangiocarcinoma, there are still many controversies in clinical diagnosis and treatment, but it is undeniable that contouring of lymph nodes and nerve plexus is an integral part of radical surgery and an important way to improve surgical results. The author’s specific approach is to routinely clear the N1 and N2 lymph nodes and their surrounding neural connective tissue, so as to “skeletonize” the vessels in the hepatoportal area and reveal them in a “bridge-like” manner. The lymph nodes of the cavernous trunk (No.9), although they belong to N3, are often included in the contouring scope because the peri-abdominal artery plexus is easily invaded by the tumor and is sometimes cleared, which is often accompanied by clearing group 5 and group 7 lymph nodes; in some cases, for example, if extended surgery is really needed, clearance of the superior mesenteric lymph nodes and peri-abdominal aortic lymph nodes can be considered. However, it should be emphasized that extensive overdissection of the plexus may cause severe gastrointestinal dysfunction and affect the patient’s quality of life, and should be cautioned against.