1.Basic principles of hepatectomy: ①Thoroughness, maximum complete resection of tumor, so that there is no residual tumor on the cutting edge; ②Safety, maximum preservation of normal liver tissue, reducing the surgical mortality and surgical complications. 2. Classification of hepatectomy methods. Hepatectomy includes radical resection and palliative resection. It is generally believed that the criteria for radical resection of hepatocellular carcinoma can be divided into 3 levels according to the degree of surgical perfection. Grade I: complete resection of the tumor seen by the naked eye and no residual cancer at the cut edge. Grade Ⅱ criteria: 4 conditions are added to the grade Ⅰ criteria: (1) the number of tumors is ≤ 2; (2) no cancer thrombus in the main portal vein and primary branches, the common hepatic duct and primary branches, the main hepatic vein and inferior vena cava; (3) no metastasis in the hilar lymph nodes; (4) no extra-hepatic metastasis. Grade III criteria: On the basis of grade II criteria, the condition of negative postoperative follow-up results should be added, that is, for those with increased serum AFP before surgery, the AFP should be reduced to normal and no residual tumor should be seen on imaging within 2 months after surgery. 3. Indications for hepatectomy. (1) Basic conditions of patients: mainly the general condition can tolerate the operation; the liver lesion can be removed; the reserved liver function can be fully compensated. Specific conditions include: good general condition, no obvious organic lesions of important organs such as heart, lungs and kidneys; normal liver function, or only mild impairment (Child-Pugh grade A), or liver function grading is grade B, which is restored to grade A after short-term liver protection treatment; liver reserve function (such as ICGR15) is basically within the normal range; no unresectable extrahepatic metastatic tumor. It is generally considered that ICG15 <14% can be used as the threshold for safely performing major hepatectomy with low chance of liver failure. (2) Local lesions for radical hepatectomy must meet the following conditions: ① single hepatocellular carcinoma with smooth surface, clear surrounding boundaries or pseudo-envelope formation, and <30% of liver tissue destroyed by tumor; or >30% of liver tissue destroyed by tumor, but the tumor-free side of the liver has obvious compensatory enlargement, reaching more than 50% of the standard liver volume; ② multiple tumors with <3 nodes and confined to one segment or one lobe of the liver. one segment or within one lobe. For multiple hepatocellular carcinoma, studies have shown that patients with multiple hepatocellular carcinoma with <3 tumors can benefit significantly from surgery if the conditions for surgery are met; if the number of tumors is >3, the outcome is not better than non-surgical treatment such as hepatic artery interventional embolization, even if surgical resection has been performed. (3) Laparoscopic hepatectomy: Currently, laparoscopic hepatectomy for hepatocellular carcinoma is increasingly performed, and its main indications are isolated cancer foci, <5 cm, located in 2-6 liver segments; it has the advantages of small trauma, low blood loss and operative mortality. Therefore, some scholars believe that laparoscopic hepatectomy performs better for well-positioned hepatocellular carcinoma, especially for early-stage hepatocellular carcinoma; however, prospective comparative studies with traditional open surgery are still needed. (4) Local lesions for palliative hepatectomy must meet the following conditions: ① 3-5 multiple tumors beyond half of the liver with multiple limited resections; ② tumors confined to 2-3 adjacent liver segments or half of the liver with significant compensatory enlargement of tumor-free liver tissue to more than 50% of the standard liver volume; ③ hepatocellular carcinoma in the central region of the liver (middle lobe or segments IV, V, VIII) with significant compensatory enlargement of tumor-free liver tissue (3) Hepatocellular carcinoma in the central region of the liver (middle lobe or segments IV and V and VIII) with significant compensatory enlargement of tumor-free liver tissue, reaching more than 50% of the standard liver volume (5) Palliative hepatectomy also involves the following cases: hepatocellular carcinoma combined with portal vein thrombosis (PVTT) and/or vena cava thrombosis, hepatocellular carcinoma combined with bile duct thrombosis, hepatocellular carcinoma combined with cirrhotic portal hypertension, and resection of difficult-to-cut hepatocellular carcinoma. Each of these conditions has its corresponding indications for surgical treatment (see Table 3). Hepatocellular carcinoma with portal vein carcinoma thrombosis is a common presentation of intermediate to advanced HCC. In this group of patients, if the tumor is limited to half of the liver and the embolus is expected to be removed intraoperatively, surgical resection of the tumor and removal of the embolus through the portal vein can be considered, followed by interventional embolization and portal vein chemotherapy. It is also common for hepatocellular carcinoma to invade the bile ducts and form bile duct emboli, resulting in obvious jaundice. For obstructive jaundice formed by cancer embolus, if the tumor can be surgically resected and the embolus can be removed, jaundice can be relieved quickly, so jaundice is not an obvious contraindication to surgery. In addition, for hepatocellular carcinoma that is not suitable for palliative resection, palliative non-resective surgical treatment should be considered, such as intraoperative hepatic artery ligation and/or hepatic artery and portal vein cannulation chemotherapy. For the treatment of microscopic intrahepatic lesions deserves attention. Some microscopic lesions are not detected by imaging or intraoperative exploration, resulting in a higher recurrence rate after hepatic resection. If incomplete resection is suspected, then postoperative TACE is the ideal choice, which has the significance of checking residual cancer foci in addition to the significance of treatment. If there are residual cancer foci, timely remedial measures should be taken. In addition, postoperative cases should be examined for hepatitis viral load (HBV DNA and/or HCV RNA); if indicated, antiviral treatment should be actively carried out to reduce the possibility of recurrence of liver cancer. 4. Improve surgical techniques. In principle, hepatectomy should be considered for single tumor with sufficient liver reserve function and no extrahepatic metastasis, large vessel invasion or portal vein thrombosis; hepatectomy should also be considered for multiple tumors that are technically feasible and meet the above conditions. However, the surgical complexity and radical resection rate of intermediate and advanced hepatocellular carcinoma, especially giant or multiple tumors, are still relatively low. The means to improve the resectability of liver tumors include: preoperative chemoembolization via hepatic artery can shrink the tumor in some patients and then resect it; embolization of the liver lobe where the main tumor is located via portal vein can compensate for the enlargement of the remaining liver and then resect it, which is clinically reported to have few toxic side effects and is safer and more effective. For large tumors, an anterior approach to hepatectomy without freeing the periportal ligament can be used to directly separate the liver parenchyma and intrahepatic ducts, and then free the ligament and remove the tumor. For multiple tumors, surgical resection combined with intraoperative ablation (e.g., intraoperative radiofrequency) can be used to treat the tumors at the margins of the liver and radiofrequency to treat the deeper tumors. For portal vein or hepatic vein embolism, portal vein embolization should be performed by blocking the portal vein flow on the healthy side to prevent the spread of the embolism. For hepatic vein embolism, whole liver blood flow can be blocked and the embolism can be removed as much as possible. For hepatocellular carcinoma with bile duct embolism, if the tumor has partially invaded the bile duct wall while removing the embolism, the affected bile duct should be removed and the bile duct should be reconstructed at the same time to reduce the local recurrence rate. 5.Preventing postoperative metastasis recurrence. The high rate of recurrence and metastasis after surgical resection of middle and late stage hepatocellular carcinoma is related to the existence of microscopic disseminated foci or multicenter occurrence before surgery. Once recurrence occurs, it is often difficult to have another chance of resection. Local non-surgical treatment and systemic treatment can be adopted to control tumor development and prolong patients' survival. For high-risk recurrences, clinical studies have confirmed the effectiveness of postoperative prophylactic interventional embolization to detect and control postoperative microscopic intrahepatic residual cancer. Although there are randomized clinical studies suggesting that alpha interferon can prevent recurrence, its effect on the long-term recurrence rate and different types of hepatitis patients is still controversial, and it is not a recognized standard treatment for recurrence prevention. 6. Contraindications to surgery: (1) poor cardiopulmonary function or combined with serious diseases of other important organ systems that cannot tolerate surgery; (2) severe cirrhosis and poor liver function Child-Pugh grade C; (3) extrahepatic metastases already exist.