Primary hepatocellular carcinoma refers to the cancer that occurs from hepatocytes or intrahepatic bile duct cells. It is one of the common malignant tumors in China, and its mortality rate ranks the third among the malignant tumors of digestive system, after stomach cancer and esophageal cancer. About 200,000 people die of liver cancer in China every year, accounting for 45% of global liver cancer deaths.
The treatment of liver cancer has been an important issue for medical practitioners in China for many years. The traditional treatment method is surgical resection, but the majority of liver cancer patients have a history of cirrhosis and poor liver function, and the surgical resection rate is less than 20% due to the influence of tumor location, number, patient’s general condition and other factors. Microwave ablation is a fast developing thermal ablation technique for tumor treatment in the last decade or so. The microwave is used to produce heat actively under the action of electromagnetic field through two mechanisms: dipole and ion heating, and reaches high temperature rapidly in a short period of time.
It has the advantages common to thermal ablation techniques, such as easy to operate, less invasive, reproducible and can achieve complete local necrosis. Compared with radiofrequency and laser ablation, microwave ablation also has the characteristics of rapid warming, strong coagulation ability, less influence by blood flow factors, simultaneous action of multiple needles, large and stable coagulation range, etc. It has become a very promising and promising treatment tool in thermal ablation therapy.
Indications and contraindications
1.Indications.
(1) Microwave ablation (or radiofrequency) is the best alternative to surgery for patients with single tumor with diameter ≤125px or multiple nodules with maximum diameter ≤75px, without vascular or bile duct invasion or distant metastasis, and early stage liver cancer with liver function Child grade A or B. For small hepatocellular carcinoma with single tumor diameter ≤75px, radical ablation can mostly be obtained.
(2) Small hepatocellular carcinoma without serious organ dysfunction such as liver, kidney, heart and brain, normal or near normal coagulation function, unwilling to receive surgical treatment and deep or central small hepatocellular carcinoma;
(3) Liver cancer that cannot be surgically resected for various reasons such as recurrence after surgical resection or mid- to late-stage cancer;
(4) Ablation therapy can be adopted for liver metastatic tumors after chemotherapy, patients waiting for liver transplantation before controlling tumor growth and recurrence of metastasis after transplantation.
(5) The distance of the tumor from the common hepatic duct, right and left hepatic ducts of the hepatic portal is at least 5 mm.
(6) For tumors adjacent to the heart, diaphragm and gastrointestinal canal, microwave ablation combined with anhydrous alcohol injection can be used;
(7) For multiple lesions or tumors >125px, according to the patient’s liver function, hepatic artery chemoembolization (TACE or TAE) can be adopted followed by microwave ablation;
(8) Liver metastatic cancer, no matter single or multiple tumors, needs to be combined with systemic chemotherapy or endocrine therapy (for endocrine-dependent tumors such as prostate cancer or breast cancer), etc., and attention should always be paid to the primary foci.
(9) For those patients with large and numerous tumors that cannot be treated surgically and other methods such as hepatic artery chemoembolization have no significant effect. The purpose of treatment is to reduce the tumor load to slow down the disease, reduce pain and prolong life.
2. Contraindications
(1) Diffuse hepatocellular carcinoma, combined with portal trunk to secondary branches or hepatic vein thrombosis;
(2) Child Pugh grade C liver function, TNM stage IV or infiltrative tumor;
(3) Significant atrophy of the liver, tumor is too large and the ablation area should be more than 1/3 of the liver volume;
(4) Tumors located on the visceral surface of the liver, with more than 1/3 of them being exposed;
(5) Recent bleeding from ruptured esophagogastric fundic varices;
(6) Severe functional failure of major organs;
(7) Active infection, especially inflammation of the biliary system, etc;
(8) Uncorrectable coagulation dysfunction (platelets < 30×109/L, prothrombin time >30s, prothrombin activity <40%) and hematological disorders with severe abnormalities in the blood picture;
(9) intractable massive ascites, impaired consciousness or cachexia.