Liver cancer is the “king of cancer” and one of the most common malignant tumors in clinical practice. The global incidence rate is increasing year by year and has exceeded 626,000/year, ranking 5th among malignant tumors; death is close to 600,000/year, ranking 3rd among tumor-related deaths. Liver cancer is highly prevalent in China, and currently, the number of incidences in China accounts for about 55% of the global incidence; it ranks second after lung cancer in tumor-related deaths. The number of deaths due to liver cancer exceeds 100,000 each year. The surgical resection rate of middle and late stage liver cancer is only about 5%-10%, and the surgical mortality rate is over 10%. Patients need to suffer a lot of surgical pain and cost in treatment. With the rapid development of imaging technology, percutaneous imaging-guided tumor ablation (PIGTA), as a minimally invasive tumor treatment method, has been developing rapidly in recent years at home and abroad, and has gradually become one of the common means of non-surgical tumor treatment. PIGTA is a minimally invasive tumor treatment method that has been developed rapidly at home and abroad in recent years. Commonly used local ablation techniques: radio-frequency ablation, microwave ablation, laser ablation, cryoablation, chemical ablation (ethanol, ethanol-acetate ablation) and ultrasound ablation (high intensity ablation). and High intensity focused ultrasound (HIFU).
I. What are the principles and characteristics of microwave ablation for liver cancer?
Using the clear image of CT, non-invasive and radiation-free and real-time direct monitoring, a special treatment needle (microwave antenna or microwave “tip”) is used to enter the liver tumor through skin puncture for treatment. The thermal effect of microwave needle is actually using the same principle of microwave oven to make liver cancer tissues reach a local temperature of over 70℃ within a few minutes, causing coagulative necrosis of tumor target tissues with little or no damage to surrounding tissues, thus achieving the purpose of “burning” tumor cells. The most important feature of this minimally invasive treatment is that it is less invasive and has less impact on the patient’s whole body. Microwave ablation treatment not only has no side effects such as hair loss, weakness, anorexia and decrease of white blood cells caused by radiotherapy and chemotherapy, but also has the effect of increasing the immunity of the body. Therefore, while treating the cancer, we should emphasize the protection of the liver and the safety of the treatment method and the tolerability of the patient’s organism. Moreover, some patients with special long liver cancer sites, multiple as well as liver metastases are often inoperable, or the cancer foci cannot be completely removed. However, microwave ablation therapy can still achieve good results, or at least reduce the tumor load, so as to live with cancer, prolong life and improve life quality. Secondly, the minimally invasive ablation treatment also greatly reduces the pain of patients and is easily accepted by them. It is not a dream but a reality that liver cancer can be cured without surgery.
Which liver cancer patients are suitable for microwave ablation treatment?
1.Single lesion ≤ 5 cm.
2.Multiple lesions with less than 3 lesions and the largest lesion diameter ≤ 4 cm.
3.No portal vein cancer thrombosis or extrahepatic metastasis.
What are the contraindications of microwave ablation treatment?
1.Where the ultrasound channel (puncture path) is unclear and ambiguous.
2.Severe impairment of liver function, large amount of ascites; severe impairment of kidney function; severe cardiac insufficiency.
3, Those with fever caused by infection and too poor general condition.
4.Persons with abnormal coagulation system mechanism and bleeding tendency.
5.Patients with diffuse hepatocellular carcinoma.
6.Patients with cancer who cannot cooperate with each other.
What are the advantages of microwave ablation treatment for liver cancer?
1.Minimally invasive, the treatment only uses “needle” (microwave antenna or microwave “tip” – 2mm in diameter) to enter the tumor precisely under ultrasonic guidance, and the skin only has a needle eye of less than 3mm, no scar, no suture, avoiding the damage to the whole body caused by major surgery. “It avoids the harm of major surgery to the whole body.
2.Short treatment time and high efficacy. Tumors with single lesion ≤5 cm can be inactivated at one time under local anesthesia or general anesthesia, and one treatment time only takes about 15 minutes.
Conformal ablation can be performed, which is based on the shape of the tumor, which can improve the efficacy and reduce recurrence.
4.Wide indications, for liver cancer that cannot be resected surgically, invalidated by vascular embolization or with poor liver function, ultrasonic intervention can still be used for treatment, which can achieve tumor reduction, palliative treatment, alleviate pain, prolong life and improve life quality.
5.It can be widely combined with other treatments, such as transhepatic artery embolization chemotherapy (TACE) will help to strengthen the effective control of microwave ablation tumor and expand its indications.
6.It can be repeatedly treated for many times.
7.The cost is cheap, compared with the cost of surgery, only less than one-third of the former.
V. What is the advantage of microwave ablation compared with radiofrequency ablation?
1.Microwave ablation (MWA) is an active ablation, while RF ablation is a passive ablation. In the living body, the conduction of microwave does not depend on the electrical conductivity of the tissue, and is less affected by tissue charring and dehydration, so the ablation range of microwave ablation is larger, and the temperature inside the tumor is high enough for shorter ablation time and more complete tumor inactivation.
Compared with radiofrequency ablation, microwave ablation is less affected by the cooling effect caused by blood perfusion, and can achieve uniform inactivation for tumor target areas near blood vessels.
3.Multiple microwave energy sources can be applied at the same time, so that there is no mutual interference in the process of RF ablation, and thus a larger ablation range can be achieved in a short time.
What is the efficacy of microwave ablation in treating liver cancer?
At present, microwave ablation therapy is rapidly emerging all over the world, and tens of thousands of patients with liver cancer have been reported to have achieved therapeutic efficacy comparable to that of surgery. A group of domestic reports: 288 liver cancer patients with 477 tumors underwent microwave ablation therapy. The cumulative survival rate of patients from 1 to 5 years reached 93%, 82%, 72%, 63% and 51%, respectively, among which the long-term survival rate of patients with tumor diameter < 4 cm and cirrhosis Child A grade was higher, and the local recurrence of tumor only accounted for 8%.
What are the complications and side effects of microwave ablation?
The complications of microwave ablation are similar to those of radiofrequency ablation. The side effects include mild pain, post-ablation syndrome and asymptomatic pleural effusion. The post-ablation syndrome is often characterized by low-grade fever and general malaise, the duration of which is related to the volume of tissue necrosis caused by microwave ablation and the patient’s general condition, and usually lasts about 3 days. These side effects are often self-limiting and usually do not require treatment. Serious complications include bile duct stricture, hemorrhage, liver abscess, skin burns, tumor implantation, etc., but the incidence is low.
What other solid tumors can be treated by microwave ablation?
In addition to liver cancer, liver hemangioma, thyroid tumor, peripheral lung tumor, kidney tumor, uterine fibroid tumor, etc. can be treated by microwave ablation.