Since Mouret performed the first laparoscopic cholecystectomy in 1987, laparoscopic techniques have been widely used in the fields of gastrointestinal surgery, obstetrics and gynecology, and urology for 20 years, and have achieved excellent results. With the accumulation of experience in laparoscopic liver surgery, the improvement of operating skills, and the emergence of new laparoscopic-specific instruments and equipment, the application of laparoscopic hepatectomy (LH) in the treatment of primary liver cancer has developed rapidly and shown good efficacy. It provides a new approach to both physicians’ treatment tools and patients’ treatment options. Although laparoscopic hepatectomy has been performed for ten years in the Department of Surgical Oncology, Beijing Hospital of Traditional Chinese Medicine, Lu Yiping
Although laparoscopic hepatocellular carcinoma resection has been performed for ten years, the application of this technology has been promoted rather slowly, mainly because of the differences in its therapeutic effects, especially the superiority of recent efficacy and the certainty of long-term efficacy.
1.What kind of cases are suitable for laparoscopic hepatic cancer resection
Feasibility is the main evaluation index of surgical technique, i.e., it is at least as safe and feasible as standard surgical open surgery. What can be determined is that laparoscopic hepatectomy can be performed as safely as open surgery under certain conditions. The anatomical and physiological characteristics of the liver make laparoscopic hepatectomy more difficult than open surgery, mainly in these aspects [1]: ① the liver has a dual blood supply of hepatic artery and portal vein, which is rich in blood flow and prone to bleeding during resection and difficult to control effectively intraoperatively; ② the intraoperative field of view is limited, exposure is difficult, and operation is more difficult; ③ it is difficult to apply laparoscopic techniques of open surgery for hepatectomy, such as blocking the hepatic portal, using hand flexible compression of the hepatic section to stop bleeding, suturing to stop bleeding, etc.; ④ the lack of ideal laparoscopic liver resection instruments and equipment. Therefore, the indications for laparoscopic hepatectomy are relatively narrower than those for open liver resection, and the lesion site is a key factor in whether laparoscopic hepatectomy can be performed.
There are relatively consistent views on the indications for laparoscopic hepatectomy for primary liver cancer: ① superficial hepatic occupying lesions in segments II, III, IVa, V and VI, especially marginal hepatic lesions located in the left outer lobe of the liver and the anterior segment of the right liver, are the best indications; ② tumor size should not exceed 7cm-10cm, too large tumor is difficult to operate, and too large liver section may cause uncontrollable (3) no intrahepatic metastasis and other distant organ metastasis; (4) no portal vein cancer embolism; (5) no history of upper abdominal surgery; (6) normal function of heart, lung, kidney and other important organs; (7) reserve status of liver function is an important factor in case selection, requiring liver function Child grade A or B.
2.Characteristics of laparoscopic hepatectomy for hepatocellular carcinoma
Laparoscopic hepatectomy has the characteristics of adopting different surgical methods for lesions of different locations and scopes: laparoscopic hepatectomy for hepatocellular carcinoma can be divided into laparoscopic partial hepatectomy, subhepatic segmental resection or hepatic segmental resection, lobectomy, hemihepatectomy and extended hemihepatectomy according to the different locations of tumors and different surgical methods and scopes. For tumors located in the left hepatic parenchyma, laparoscopic left hepatic lobectomy can be safely performed with the available surgical instruments and without blocking the blood flow to the whole liver. For tumors located on the surface of the right liver or at the edge of the liver, partial hepatectomy is chosen [13], without dissecting the chordae structures of the first and second hepatic hilum, and the liver can be dissected more than 1 cm from the edge of the tumor by the above-mentioned method of dissection of the liver parenchyma after freeing the liver. The application of intraoperative laparoscopic ultrasound (LUS) provides a certain guarantee for the correct assessment of the liver in the operation itself as well as the accuracy and safety of the operation. LUS can accurately determine the location and boundary of the tumor and avoid sub-total resection of the tumor; at the same time, LUS can clarify the course and relationship of the tumor adjacent to the intrahepatic vessels and bile ducts to guide liver resection and reduce the risk of sudden microscopic uncontrollable hemorrhage.
Technical features of liver dissection: successful and effective liver dissection and hemostasis is the key to laparoscopic hepatectomy. Current liver resection methods include suturing, water jet-cutter, ultrasonic scalpel, Argon-beam coagulator, microwave coagulator, and laparoscopic coagulator. coagulator), laparoscopic cutting anastomosis (ENDO-GIA), laparoscopic multifunctional surgical dissector (PMOD), ultrasonic surgical aspirator (CUSA), etc. The above methods and devices have their own advantages and disadvantages, and they are not widely accepted at present. The ideal laparoscopic liver dissection instrument should have the functions of cutting, separation, hemostasis and attraction, and should have the advantages of fast cutting speed, good hemostasis and little tissue damage, etc. The Tissuelink radiofrequency knife proposed in recent years integrates the functions of tissue hemostasis, dissection and permanent closure of the duct, with reliable hemostasis and low temperature tip, which can realize bloodless hepatectomy without blocking the hepatic portal. Summarizing the experience of various treatment units shows that 30-degree laparoscopy, low-flow pneumoperitoneal perfusion, and dedicated operating techniques, including laparoscopic ultrasound and ultrasonic knife, are necessary for surgery. If necessary, blocking techniques of the three hepatic hilar ducts can be used
3.Common complications and their preventive measures
Bleeding from the hepatic section: the liver is rich in blood flow, and coupled with the difficulty of laparoscopic application of open hepatotomy techniques such as blocking the hepatic hilum, flexible hand compression of the hepatic section to stop bleeding, and suture hemostasis, it is difficult to control bleeding effectively intraoperatively. The key to prevent hemorrhage is to pay attention to the course of large vessels during hepatectomy, and to correctly determine whether the vessels are completely clamped before cutting them off; thicker portal veins are safer to be disconnected with ENDO-GIA. Controlling central venous pressure below 5 cmH2O during surgery has been shown to be a simple and effective method to reduce intraoperative bleeding. Selective application of inflow blockade to the liver significantly reduces intraoperative bleeding, while avoiding uncontrollable hemorrhage during the procedure and intermediate open abdomen.
CO2 embolism: Very rare because CO2 is extremely soluble, CO2 embolism usually occurs when the hepatic vein or portal vein is injured and high pressure CO2 gas enters the heart in large quantities with the vein, which is the greatest cause of death during laparoscopic hepatectomy. Clamping the hepatic vein by dissecting it outside the liver prior to hepatectomy can prevent the formation of gas emboli in the hepatic vein. If intraoperative venous injury is suspected, the patient should be immediately placed in a head-down position and CO2 delivery should be discontinued to prevent air embolism. Intraoperative control of intra-abdominal pressure to less than 10 mmHg or the use of pneumoperitoneum-free laparoscopy may prevent pneumothorax.
Bile leak: often due to unclamped small bile ducts in the liver section and undetected intraoperative obstruction by blood clots, bile leak occurs postoperatively. Proper intraoperative treatment of the liver section, titanium clamping of the bile ducts and postoperative placement of drains in the liver section can prevent and manage bile leaks.
Liver function damage: It mainly occurs in cases with cirrhosis. Due to the surgical traumatic blow and large intraoperative bleeding, postoperative liver function damage is caused, manifested as ascites, jaundice, elevated transaminases and prolonged prothrombin time. The key to prevention is to strictly grasp the indications. Severe hepatic sclerosis and severe portal hypertension should be listed as contraindications to surgery.
Tumor implantation in abdominal cavity and abdominal wall: The main reason is that the tumor of hepatocellular carcinoma ruptures and overflows during surgery or removal from the abdominal cavity, resulting in implantation and metastasis in the abdominal cavity or abdominal wall incision. The key to prevention is to prevent tumor rupture, the incision line should be more than 1cm away from the edge of tumor during resection, and the resected tumor should be placed in plastic bag to extend the abdominal wall incision to avoid squeezing the tumor.
4. Feasibility and safety of laparoscopic hepatectomy for hepatocellular carcinoma
Several liver surgery centers at home and abroad applied retrospective survey methods to evaluate the feasibility and safety of laparoscopic hepatectomy. In terms of operation time, intraoperative bleeding, blood transfusion rate, postoperative complication rate, survival rate and tumor-free survival rate, there was no significant difference between laparoscopic treatment group and open surgery treatment group, while the former had significantly less hospitalization time than the latter. The reasons for less ascites and liver failure after laparoscopic liver malignancy resection than open surgery may be as follows: (1) laparoscopy does not have a large abdominal wall incision and does not cut the abdominal wall veins and round ligaments, thus ensuring effective collateral circulation; (2) intraoperative turning and touching of the liver is reduced, thus reducing the resulting damage to the liver; (3) laparoscopy can reduce ligation and cutting of lymphatic vessels, thus (3) laparoscopy reduces ligation and dissection of lymphatic vessels, thus ensuring effective lymphatic return; (4) other reasons include reduced postoperative infusion and avoidance of intra-abdominal organ exposure. As the patient recovers quickly, other treatments, such as chemotherapy or radiotherapy, can be administered to the patient earlier after surgery. The fact that laparoscopy is less intrusive to the abdominal cavity and has less postoperative intra-abdominal adhesions is beneficial to the intraoperative management of reoperation. 90% of patients with hepatocellular carcinoma have chronic liver disease and traditional open hepatectomy has a high mortality and recurrence rate. The overall 3-year survival rate and tumor-free 3-year survival rate were 93% and 64%, respectively. This group of data indicates that laparoscopic hepatectomy is not only safe and feasible, but also may replace traditional open surgery for patients with chronic liver disease, tumor located at the liver margin and tumor diameter ≤5 cm.
5.How much do patients benefit from laparoscopic hepatectomy for hepatocellular carcinoma and its development prospect
Surgical resection still plays the most important role in improving the prognosis of hepatocellular carcinoma. The widespread use and advancement of minimally invasive surgical techniques have had a great impact on traditional hepatectomy, making it challenging to improve safety and reduce invasiveness. As patients with hepatocellular carcinoma often face concomitant cirrhosis. Local excision of smaller lesions has shown to be minimally invasive, and extensive hepatectomy should be performed with caution. This is because in the case of more severe cirrhosis, the liver tissue is harder to dissect and difficult to separate, and the ultrasonic knife has poor hemostasis with more bleeding and oozing. There are still many problems that cannot be handled under laparoscopy, such as portal vein trunk with cancer embolus or bile duct cancer embolus, which can be removed by open surgery portal vein or bile duct dissection, but laparoscopy cannot do this yet. Some studies have shown that the bleeding, transfusion rate, complication rate, and mortality rate of LH are comparable to those of open hepatectomy (OH); it is significantly better than OH in terms of time to exhaustion and feeding, use of analgesics, length of hospital stay, return to work, and satisfaction, while the operation time is slightly longer and the cost of surgery is significantly higher than that of open surgery. However, its long-term efficacy needs to be further validated in a randomized controlled study with traditional open surgery in a large number of cases.
The current long-term observation shows that after laparoscopic hepatectomy, patients recovered quickly in general, especially in terms of mental and physical strength, and some of them returned to work in one month after surgery. As for the long-term efficacy of laparoscopic hepatocellular carcinoma resection, more attention is paid to the outcome of tumor-free survival. For benign liver lesions, only the surgical excision of the lesion is required, usually by marginal resection, while for malignant liver lesions, the principles of oncological treatment should be followed and the scope of resection should be the same as that of open surgery. With regard to tumor implantation and metastasis, the question of whether laparoscopic resection of hepatocellular carcinoma is ideal and whether there is an increased chance of intra-abdominal or incisional implantation after surgery is often considered. As to whether laparoscopic resection of hepatocellular carcinoma has a greater chance of intra-abdominal or incisional implantation than open surgery, preliminary results indicate that there is no significant difference between laparoscopic resection of hepatocellular carcinoma and open surgery, and the outcome is satisfactory. Due to the concept of small hepatocellular carcinoma, surgical biology of tumor, and the use of minimally invasive techniques, the surgical treatment of hepatocellular carcinoma has gradually evolved to local resection, i.e., single-segment, multi-segment, or irregular resection based on liver segments, and its long-term efficacy is no less than that of “regular” lobectomy. Complications are reduced. This is an early manifestation of the concept of minimally invasive surgery in hepatectomy. In retrospective analysis of laparoscopic hepatectomy reported in recent years, the mortality rate of laparoscopic hepatectomy has been maintained at a low level of 1% to 5% due to the improvement of hepatectomy techniques.
In summary, laparoscopic hepatectomy has the following advantages: (1) small incision in the abdominal wall and less injury. (2) Less postoperative pain, which is conducive to early activity; less impact on intestinal function, which allows early feeding, earlier recovery and shorter hospital stay. ③Postoperative hepatocellular carcinoma often requires sequential treatment, including PEI, TACE or re-operation, etc., while intra-abdominal adhesions caused by traditional open surgery can affect the next step of treatment. Laparoscopic surgery forms fewer adhesions and can provide better conditions for postoperative treatment. ④Little impact on immune function after laparoscopy, especially on cellular immunity with anti-tumor effect, which can be adjuvantly treated earlier. ⑤ For patients with combined cirrhotic portal hypertension, the incidence of postoperative ascites and liver failure is significantly reduced.
Laparoscopic hepatectomy for hepatocellular carcinoma embodies the concept of minimally invasive surgery, i.e. “eliminating tumor while maximizing preservation of the organism”. Laparoscopic hepatectomy can avoid some unfavorable factors of traditional open hepatectomy and minimize the trauma to patients if the indications are judged according to tumor site, size and preoperative liver function. However, not all cases are suitable for laparoscopic hepatectomy. Under the current conditions, laparoscopic hepatectomy is not suitable for the following cases: ① lesions located in segments I, VII and VIII, which are not easily exposed due to their special anatomical location and are adjacent to the major blood vessels of the liver, so forced surgery may lead to uncontrollable hemorrhage; ② lesions larger than 10 cm or located deep in the liver parenchyma or more than 3 liver segments need to be removed at the same time (3) hepatocellular carcinoma with more than 3 lesions, or lesions that are not large but cannot guarantee the requirement of no cancer infiltration at the cut edge; (4) lesions that have invaded the inferior vena cava and hepatic vein root, making microscopic exposure difficult and not easy to control bleeding; (5) combined with intrahepatic metastases and other distant organ metastases, portal vein cancer embolism, metastasis of hilar lymph nodes or unclear tumor boundary; (6) liver function grade Child C or other important organ insufficiency; (7) History of upper abdominal surgery with severe intra-abdominal adhesions, severe cirrhosis, and portal hypertension are relative contraindications.
With the continuous development of laparoscopic technology and special instruments, laparoscopic hepatectomy will become a new way of hepatocellular carcinoma treatment, and it is foreseeable that the number of hospitals and surgical cases choosing laparoscopic hepatectomy will increase.