Comparison of the progression-free survival, overall survival, local progression rates, complete ablation rates and the complications rate of MSA and traditional MWA in the treatment of single hepatocellular carcinoma with a diameter of ≤5cm.

HCC is a serious threat to the health of people，Early treatment of HCC results in a good prognosis for patients. Microwave ablation (MWA) is an important method for the treatment of early HCC. The traditional MWA technology has a long diameter of the ablation foci which is much larger than the transverse diameter, so in order to obtain a sufficient transverse diameter, the long diameter is often too large beyond the tumor boundary. That will cause too much normal liver tissue is unnecessarily damaged, especially for patients with severe liver cirrhosis or patients with liver cirrhosis who have undergone liver resection. In addition, it is easy to cause damage to adjacent vital tissues and organs. Changes in tissue properties during ablation affect the stability of the microwave field, resulting in unpredictable ablation shapes, which may cause omissions during tumor ablation, especially in multiple overlapping ablation, resulting in incomplete ablation, or increasing the risk of local tumor progression after treatment. Microwave spherical ablation (MSA) technology is a new MWA technology. With the help of temperature control technology, field control technology and wave control technology, a single needle can produce predictable spherical ablation lesions. Theoretically, MSA can improve the controllability of the ablation foci, which is suitable for the purpose of conformal ablation of large tumors in clinical practice, thereby minimizing the damage of local thermal ablation to liver tissue and adjacent important organs. However, there are few reports on the comparison of the therapeutic effect of MSA and traditional MWA. This study intends to conduct a prospective randomized controlled study based on the two mature microwave treatment methods of MSA and traditional MWA ablation to explore the effectiveness and safety of MSA in clinical application, providing evidence-based medical evidence for the clinical application of MSA.

Inclusion Criteria:

1. Patient has high risk factors for HCC and was first diagnosed of HCC by by contrast-enhanced imaging (CECT/CEMRI/CEUS) and/or pathology ;
2. Age range 18 to 75 years old;
3. Single lesion with tumor diameter ≤5cm;
4. Patient refuses surgery and determines to undergo microwave ablation
5. Liver function Child Pugh A or B;
6. No extrahepatic metastasis or portal invasion;
7. Patient signs the informed consent.

Exclusion Criteria:

1. The lesion has received treatment, including local ablation therapy and TACE therapy, etc;
2. With portal vein invasion or extrahepatic metastases;
3. Patient is with severe cardiopulmonary insufficiency.
4. Patient is a pregnant or breastfeeding women.
5. Patient is considered to be unsuitable to participate in the study