Specification for local ablation treatment of hepatocellular carcinoma (guidelines) Part III.
Specification for local ablation treatment of open liver cancer (Draft)
(Interventional Ultrasound Group, Ultrasound Medicine Branch, Chinese Medical Association, July 2011, written by Yuehua Wang, Minhua Chen) Yuehua Wang, Department of General Surgery, Xuanwu Hospital, Capital Medical University
Preface: (Commonality)
Primary hepatocellular carcinoma (hereafter referred to as liver cancer) is a common malignant tumor in China. Although surgery used to be the only treatment that could be expected to cure liver cancer, the overall surgical resection rate is only about 15% due to the fact that most liver cancer cases are accompanied by serious liver diseases such as hepatitis and cirrhosis. For liver cancers that are not suitable for surgical resection, research on local ablation and destruction, represented by radiofrequency ablation, has emerged in the past 20 years, which has played an active role in the treatment of liver cancer and has achieved better efficacy. There are three routes of local ablation treatment: percutaneous, trans-laparoscopic and trans-open surgery. The indications and contraindications of local ablative therapy, operation technique specification and treatment prognosis of each route have both common features and many differences. In order to express them clearly, the specifications (guidelines) for local ablation treatment of liver cancer by different routes are planned in general, formulated separately and set up as independent chapters.
I. General technical description (technical introduction, principles, classification)
1.1
Local ablation techniques (commonality)
Local ablation therapy represented by radiofrequency ablation is to target and locate the tumor with the guidance of imaging technology and selectively induce tumor necrosis by physical or chemical methods. The imaging guidance techniques include ultrasound, CT and MRI; the treatment routes are percutaneous, trans-laparoscopic and trans-open surgery. The characteristics of radiofrequency ablation therapy are firstly, it acts directly on the tumor, which has the advantage of high efficiency and rapidity; secondly, the treatment scope is limited to the tumor and its surrounding tissues, which has little impact on the body and can be applied repeatedly. In the past decade or so, local ablation therapy has gained rapid development, and because of its precise efficacy, especially in the treatment of small hepatocellular carcinoma, the efficacy of radiofrequency ablation has been similar to that of surgical resection, so it is considered as one of the local radical treatments for small hepatocellular carcinoma besides surgical resection.
1.2
Principles and classification of local ablation therapy (commonality)
Tumor-induced necrosis can be achieved by direct contact of tumor with specific chemical substances or changing its temperature. Local ablative therapy can be classified into chemical ablative therapy and physical ablative therapy according to the principle. Chemical ablation refers to the dehydration, necrosis and disintegration of local tissue cells by chemical methods (i.e. injection of chemical substances into the lesion, such as anhydrous alcohol, acetic acid, etc.), so as to achieve the purpose of inactivating the tumor lesion. percutaneous acetic acid injection (PAI), etc. Physical ablation is a treatment method to inactivate tumor lesions by heating local tissues or freezing local tissues, mainly radiofrequency ablation (RFA), microwave coagulation therapy (MCT), cryoablation, and high intensity focused ultrasound (HFE). high-intensity focused ultrasound (HIFU)
focused ultrasound (HIFU), laser ablation therapy, etc. The following part of this specification is represented by radiofrequency ablation, which is suitable for microwave curing and can be used as reference for other local ablation treatment methods.
1.3 Selection of radiofrequency ablation treatment routes for hepatocellular carcinoma (commonality)
Since various routes of radiofrequency ablation have their own characteristics, advantages and disadvantages, the principle of choosing the route of radiofrequency ablation treatment should be based on safety, effectiveness and combined treatment, and the advantages of various routes should be brought into play. Generally speaking, percutaneous radiofrequency ablation is used for single tumor in the liver with maximum diameter ≤5cm; or the number of tumors ≤3 with maximum diameter ≤3cm. Trans-laparoscopic radiofrequency ablation is suitable for tumors located under the liver envelope, or adjacent to the gallbladder, gastrointestinal, etc., or where ultrasound/CT does not show clearly or where percutaneous puncture is difficult. Open radiofrequency ablation therapy is suitable for those whose tumors are difficult to be performed by the above 2 methods, or whose tumors are found to be unresectable by surgical exploration and for adjuvant surgery. For tumors in high-risk areas, including those adjacent to the gallbladder, gastrointestinal tract, bile duct, diaphragm or located in the hilar region or subhepatic peritoneum, ablation should be performed under direct vision (some can be trans-laparoscopic) using open surgery as much as possible in order to isolate and protect adjacent organs. The specific indications and contraindications for radiofrequency ablation by various routes need to be referred to the relevant details in each section.
1.4 Characteristics of radiofrequency ablation of open liver cancer
Open surgical exploration can make a comprehensive observation of the main lesion, surrounding subfoci and perihepatic invasion or metastasis, and intraoperative ultrasound can detect some small lesions that cannot be detected by preoperative imaging. Open radiofrequency ablation can simultaneously perform resection of the primary lesion or larger tumors in the liver, and can perform hepatic portal blood flow blockage to increase the extent of tumor necrosis. For some tumors adjacent to other important organs such as diaphragm and gastrointestine, the liver can be adequately freed and isolated with gauze pads to avoid causing accidental injury to the adjacent organs. For patients with poor coagulation function and easy bleeding, bleeding can be effectively controlled. At the same time of radiofrequency ablation of hepatocellular carcinoma, the gallbladder adjacent to the tumor or the gallbladder with gallbladder stones can be removed. Radiofrequency ablation of hepatocellular carcinoma in open abdomen can improve the rate of complete ablation of tumor and reduce the rate of local recurrence.
Selection of radiofrequency ablation treatment for open liver cancer (treatment purpose and principles, indications and contraindications)
2.1
Treatment purpose (commonality)
Radiofrequency ablation for hepatocellular carcinoma has evolved from a local treatment method for hepatocellular carcinoma not suitable for surgical resection to an alternative treatment method for those who can be surgically resected, or as an adjuvant treatment to hepatectomy, and is an extension of surgical treatment technology. The treatment purpose of radiofrequency ablation is to perform radical tumor ablation for those who have the conditions for radical treatment and palliative treatment for those who do not.
2.2 Treatment principles (commonality)
The basic principle of radiofrequency ablation treatment is to insist on safe, effective and combined treatment, including the following.
(1) The patient’s condition and tumor biological behavior must be fully evaluated before radiofrequency treatment, to predict the feasibility and effect of radiofrequency ablation, and to determine the treatment and combined treatment measures and steps.
(2) Adequate imaging assessment before treatment, formulation of treatment plan and strategy according to the extent and location of tumor infiltration, ensuring sufficient safety range and obtaining one-time, conformal and complete ablation treatment as far as possible.
(3) Selecting suitable imaging-guided pathways and monitoring the treatment process.
(4) Appropriate comprehensive treatment plan and scientific and reasonable follow-up plan.
2.3 Indications and contraindications of radiofrequency ablation for open liver cancer
2.3.1 Applicable scope
(1) For those who are suspected to have cancer cells remaining in the tumor cut edge after resection of hepatocellular carcinoma, local ablation treatment can be performed on the residual liver section.
(2) After resection of the main lesion, local ablation treatment can be performed on the residual lesion in the liver found by intraoperative ultrasound examination, which not only reduces the residual cancer and makes the treatment more complete, but also preserves the normal liver tissue to the greatest extent.
(3) Those whose tumors cannot be resected by surgical exploration, or those who are preoperatively evaluated to be inoperable and not suitable for percutaneous puncture or laparoscopic radiofrequency ablation.
(4) patients who are preoperatively evaluated as capable of surgical resection but are unwilling to accept alternative methods of surgical resection and are not suitable for percutaneous puncture or trans-laparoscopic radiofrequency ablation
(5) Recurrent hepatocellular carcinoma after hepatectomy, which is not suitable for re-hepatectomy and not suitable for percutaneous puncture or trans-laparoscopic radiofrequency ablation.
(6) For unresectable massive hepatocellular carcinoma, local ablation should be used in combination with hepatic artery cannulation after embolization chemotherapy.
2.3.2 General conditions of patients
The general requirements of hepatectomy are the same.
(1) Patients are in good general condition without significant organic lesions of important organs such as heart, lung and kidney.
(2) Normal liver function, or only mild impairment, which is grade A according to liver function grading; or liver function grading is grade B, and liver function is restored to grade A after short-term liver protection treatment (Child-Pugh liver function grading).
(3) Liver reserve function (such as ICGR15) is basically within the normal range.
2.3.3 Local condition of tumor
With reference to the requirements of surgical liver resection, the reserve of remaining liver function after radiofrequency ablation should meet the needs.
(1) single tumor with maximum diameter ≤ 5 cm; or number of tumors ≤ 3 with maximum diameter ≤ 3
cm; radical ablation can be performed in the absence of vascular cancer thrombus and adjacent organ invasion.
(2) For single tumors >5 cm in diameter or multiple tumors >3 cm in maximum diameter that cannot be surgically resected, radiofrequency ablation can be used as part of palliative treatment or combined treatment.
(3) Special cases: combined with portal vein cancer tethering, suitable for portal vein trunk dissection to remove the cancer embolus and simultaneous palliative liver tumor ablation. Primary liver cancer combined with bile duct cancer embolism is suitable for bile duct dissection and removal of cancer embolism, T-tube drainage and palliative liver tumor ablation at the same time. Liver cancer invading gallbladder is suitable for gallbladder resection and palliative liver tumor ablation at the same time.
2.3.4 Contraindications
Patients with poor general condition, Child-Pugh C liver function, which cannot be improved by liver care treatment; patients with ruptured esophageal (fundic) varices bleeding within 1 month before treatment; patients with uncorrectable coagulation dysfunction and severe blood abnormalities, those with severe bleeding tendency; patients with severe liver, kidney, heart, lung, brain and other major organ failure; patients with impaired consciousness or unable to cooperate with postoperative rehabilitation; and patients who are expected to have a better quality of life and survival after RF ablation. Patients whose quality of life and survival are not significantly improved after the treatment. However, the presence of extrahepatic metastases alone should not be considered a contraindication, and radiofrequency ablation can still be used to control intrahepatic lesions in the absence of the aforementioned contraindications.
Patients whose general condition cannot meet the general requirements of open surgery are also not suitable for open radiofrequency ablation.
Conditions for open radiofrequency ablation (equipment and technical conditions, operators)
3.1 Basic equipment conditions and requirements (refer to the part of percutaneous radiofrequency ablation + open abdominal surgery conditions)
3.1.1 Hospital department conditions
Basic conditions of general surgery or hepatobiliary surgery, with qualifications to perform liver surgery and radiofrequency ablation treatment and related departmental settings.
Anesthesiology operating room: with the basic equipment and conditions for performing liver surgery.
3.1.2 Instruments and equipment
Radiofrequency ablation instrument and intraoperative ultrasound image guidance equipment that meet the relevant standards.
3.2 Operator conditions (access system, training system)
3.2.1
Access system
In accordance with the requirements of the health department.
3.2.2
Training system
Systematic training of radiofrequency ablation technology for general surgeons or hepatobiliary surgeons who are qualified to perform liver surgery.
Corresponding training will be given to surgical auxiliary staff and postoperative nursing staff.
IV. Pre-treatment preparation (patient conditions, treatment plan and expectations)
4.1 Patient conditions (commonality)
(1) Understand the medical history (containing no history of bleeding, history of abdominal surgery, history of infection, diabetes, pacemaker, etc.).
(2) Improve pre-treatment investigations: routine blood, biochemical routine, coagulation function, tumor markers, ECG, chest X-ray, ultrasound, imaging such as liver CEUS/CT/MR, and cardiopulmonary function tests if necessary.
(3) Disease assessment: assessment of tumor status based on US/CEUS/CT/MR and other imaging examinations; assessment of TNM stage (imaging); assessment of liver function Child-Pugh classification.
4.2
Treatment prognosis and strategy (commonality)
(1) Determine the treatment mode and expectation: determine whether adjuvant ablation, simple ablation or combined radiofrequency ablation and interventional chemoembolization (TACE); expect to do radical ablation or palliative ablation.
(2) Ablation strategy: image guidance, real-time monitoring , range of safe ablation margins. Ultrasound (try to choose ultrasonography if possible), three stage CT/MRI of the liver to evaluate the tumor condition and select reasonable guidance and ablation treatment instruments.
(3) Preparation of radiofrequency ablation instruments: check whether the radiofrequency ablation treatment instruments are in working condition, whether they can work normally, whether the electrodes or lines are ready before treatment.
(4) Sign the informed consent form: The operator should carefully explain the advantages and limitations of the procedure, the treatment plan and alternatives, the basic procedure, the risks and possible complications, the postoperative treatment and follow-up, etc. to the patients and their families to obtain their understanding and support, and ask each patient or family member to sign the informed consent form.
V. Procedure of radiofrequency ablation for open liver cancer (treatment procedures, operation points, precautions, complications and prevention)
5.1 Treatment procedure
(1) The preoperative preparation is the same as that required for hepatectomy.
(2) Anesthesia mode: general anesthesia with tracheal intubation.
(3) Routine open abdominal exploration to clarify the diagnosis and perform puncture biopsy if necessary (diagnostic criteria refer to the diagnostic criteria formulated by the Hepatocellular Carcinoma Professional Committee of the Chinese Anti-Cancer Association in 2001).
Intraoperative ultrasound
(4) Radiofrequency ablation, see operation points for details.
(5) Placement of abdominal drainage tube after completion of radiofrequency ablation and closure of abdomen.
(6) Routine postoperative fasting and monitoring of vital signs, as in hepatectomy. Pay attention to the monitoring of blood routine, liver and kidney function, etc. And give treatment of liver protection, infection prevention, analgesia, hemostasis, etc. to prevent complications; complications should be actively dealt with.
5.2 Operation points
(1) Free the perihepatic ligament to expose the tumor and protect the surrounding normal tissues and organs.
(2) Intraoperative ultrasound, determine the needle entry point, needle entry angle and needle deployment plan. (2) Insert the electrode needle into the tumor, arrange the needle according to the predetermined plan and ablate the treatment; try to choose to pass through part of the normal liver first before entering the tumor.
(3) Referring to the requirements of the instructions of the ablation therapy instrument used, ablation therapy was performed, point by point. To ensure the effect of ablation treatment, the ablation range should strive to reach the safe boundary of 0.5 cm. The overlapping ablation mode of multiple needles and multiple points can expand the ablation range and reduce the occurrence of leakage; after the ablation is completed, strive to perform needle tract ablation when dialing the needle to prevent postoperative bleeding and tumor implantation along the needle tract.
(4) Before the end of treatment, ultrasound scan the liver again comprehensively to make sure that the ablation range has completely covered the tumor and strive for a safe ablation boundary of 0.5~1.0 cm to exclude the possibility of complications such as tumor rupture, bleeding, (hem)pneumothorax and adjacent organ damage.
5.3 Prevention and management of complications
Adequate preoperative preparation, strict adherence to the operation specification during the operation, accurate positioning of ablation, and protection of perihepatic tissues and organs are important methods to reduce the incidence of complications. The serious complications of open radiofrequency ablation mainly include intra-abdominal bleeding, bile leakage, infection, tumor implantation, liver failure, and gastrointestinal bleeding.
(1) Intra-abdominal bleeding: mostly caused by multiple tumor punctures during surgery, incomplete needle tract ablation, bleeding from tumor puncture points, incomplete hemostasis during surgery or poor coagulation function of patients. Prevention: strictly grasp the indications, and for patients with poor coagulation function in cirrhosis, correct it before treatment. Treatment: detect vital signs, actively dilate, infuse fluids, stop bleeding, transfuse and raise blood pressure, etc., and then surgically explore and stop bleeding or combine with interventional hepatic artery embolization if necessary.
(2) Bile leak: often caused by intraoperative puncture into the larger bile duct injury. Prevention: Avoid puncturing to thick bile ducts during the operation, and after the completion of ablation, besides checking whether there is bleeding from the puncture needle tract, we should also pay attention to whether there is bile leakage, and if bile leakage is found, it should be treated appropriately.
(3) Infection: mainly liver abscess, subphrenic effusion, etc. Prevention: strict aseptic operation, postoperative placement of abdominal drainage, postoperative antibiotics can be applied to prevent infection.
(4) Tumor implantation: mainly caused by repeated punctures. Prevention: Puncture should be accurately positioned and repeated punctures should be avoided; if the needle is too deep, the electrode needle should not be returned directly, but should be ablated in situ and then returned for repositioning.
(5) Liver failure: The main reason is the heavy degree of cirrhosis and poor liver function before treatment; or the occurrence of serious complications (such as infection, bleeding, etc.). Prevention and treatment: Strictly grasp the indications, cases with Child-Pugh grade C liver function, large amount of ascites and severe jaundice are contraindications; pay attention to the prevention of other complications after the operation, prevention of infection and active liver protection treatment. At the same time, it is necessary to avoid too large an ablation area around the tumor.
(6) Damage to adjacent organs: If the tumor is adjacent to the gallbladder, gastrointestinal tract, bile duct, diaphragm, etc. or located in the first hepatic portal area, the adjacent organs need to be isolated and protected.
(7) Gastrointestinal bleeding: The main causes are bleeding from varices in the lower esophagus or bleeding from stress ulcers. Prevention and treatment: Patients with severe portal hypertension should be treated for portal hypertension before surgery; postoperative acid control agents should be routinely used to prevent stress ulcer bleeding. Post-hemorrhage treatment: detect vital signs, fasting, active volume expansion, fluid administration, hemostasis, blood transfusion, acid control, and pressure elevation, etc., and endoscopic hemostasis if necessary.
(8) Post-ablation syndrome: The main manifestations are fever and pain, etc. Rarely, there are hematuria and chills, etc. The specific causes are unknown. The main treatment is to strengthen postoperative monitoring, infusion, pain relief, symptomatic treatment, regular testing of liver and kidney function, and corresponding treatment.
(9) Skin burns caused by negative electrode plate: Radiofrequency ablation of larger tumors takes longer time and more heat is transferred through the negative electrode plate, which may occasionally cause skin burns at the negative electrode plate. In the process of radiofrequency ablation, ice bag can be placed at the negative electrode plate to cool down the temperature to prevent burns. Once the skin burn occurs, it should be treated as burn injury in time.
VI. Evaluation of prognosis (intraoperative evaluation, postoperative evaluation, treatment limitations and remedial measures, follow-up long term evaluation)
6.1 Intraoperative evaluation
After the completion of intraoperative radiofrequency ablation treatment, there should be a clear judgment of this radiofrequency ablation treatment by intraoperative ultrasound, that is, whether the treatment expectation is achieved, and whether complete ablation or palliative ablation is achieved.
6.2 Postoperative evaluation (commonality)
The liver was reexamined 1 month after treatment with either a three-stage CT/MRI, or ultrasonography, to evaluate the ablation efficacy of.
(1) Complete ablation (complete
(1) Complete ablation (response, CR): If the tumor is hypointense in the area of the tumor (hyperechoic on ultrasound) and no enhancement is seen in the arterial phase, and the safety margin reaches 0.5~1.0 cm on CT/MR or ultrasonography follow-up.
(2) Incomplete ablation (incomplete
(2) Incomplete ablation (ICR): If there is still tumor residue after two ablations, it is determined that the ablation treatment has failed and other treatment means should be used.
(3) Basic complete ablation: In actual situation, we can encounter those who have completely ablated the tumor area, but the safety margin is less than 0.5~1.0cm. (How to define this situation needs further study)
6.3 Treatment limitations and remedial measures (commonality)
It should be fully recognized that the treatment of hepatocellular carcinoma requires multidisciplinary and comprehensive treatment. The efficacy of tumor ablation has three conditions: complete ablation, incomplete ablation and basic complete ablation. For the latter two conditions, it is recommended to combine other treatment methods and implement remedial treatment and preventive treatment before recurrence or metastasis.
6.4 Follow-up long term evaluation (commonality)
The liver was reviewed monthly for the first 2 months after the operation with triphasic CT/MRI, or ultrasonography, as well as liver function and tumor markers, to observe the necrosis of lesions and changes in tumor markers. After that, tumor markers, ultrasonography, or liver triple CT/MRI were reviewed every 2 to 3 months (ultrasonography and CT/MRI were spaced apart). Tumor markers, ultrasonography, or liver triple CT/MRI (ultrasonography and CT/MRI spaced apart) were reviewed every 3 to 6 months after two years. Tumor recurrence and progression were judged according to the follow-up results as follows.
(1) Local tumor progression (local
tumor progression): after complete ablation of the tumor, new lesions appear at the edge of the ablation site, and the new lesions are connected to the ablation site.
(2) New lesion(new
(2) new lesion: a new lesion occurring in other parts of the liver.
(3) distant metastasis (distant
(3) distant metastases (recurrence): metastases outside the liver.
VII. Medical record recording and management (commonality)
Detailed recording of case information, RF ablation form is the same as the surgical record, the items and contents of the record should meet the need of comparative study with other routes of RF ablation or surgical resection.
(1) Detailed records of what is seen on surgical exploration, treatment procedures and intraoperative abnormalities.
(2) Record intraoperative complications and resuscitation management (including medication).
(3) Confirm that there is no significant bleeding immediately after treatment, obtain consent from the anesthesiologist to send the patient back to the ward, and hand over the shift to the ward or patient.
(4) Detailed explanation of postoperative precautions, with textual explanation (forms may be attached)
(5) Both the operator and the anesthesiologist should sign.
VIII. Documentation (evidence of the basis and validity of this guideline)
Reference basis (omitted)