Ablation is derived from the English word “ablation”, which roughly means “excision”, “elimination” and so on. Tumor ablation is defined as the direct application of chemotherapy or heat therapy to a tumor (or several tumors) in order to destroy or completely destroy the tumor, so that the entire tumor, including its peripheral normal tissue of about 0.5-2 cm, is completely coagulated and necrotic and inactive, so that the tumor and the surrounding tissue of a certain thickness are completely inactive, forming a coagulated and necrotic spherical body that completely envelops the entire tumor. The inactivated tumor is located in it. The inactivated tumor is located in it, and the effect of removing the tumor is equivalent to that of surgical lumpectomy, but with minimal trauma. It is an efficient, minimally invasive and promising technique for in situ tumor inactivation. It is directly aimed at differentiating it from oral, intravascular, or peripheral intravenous routes of drug administration. The concept of image guidance is emphasized from an imaging perspective, and impact guidance is highlighted as the key to the success of these treatments. The most commonly used tumor ablation modalities in current clinical practice should be divided into two main categories: chemical ablation and temperature ablation. Their common feature is the in situ destruction of tumors by chemical or physical methods through various ways of entering the tumor and injecting chemical drugs or introducing cold and heat source generators under imaging guidance. Because of the clear target and strong effect of ablation and no clear toxic side effects on normal tissues, some people even call such in situ inactivation techniques as “knives” that do not need to operate, such as chemical knife, radiofrequency knife, laser knife, Helio knife, superconducting argon helium knife and so on. The treatment method is similar to the effect of surgical resection. Chemical ablation: These treatments are based on the injection of recognized chemical drugs directly into the tumor to dehydrate the tumor and the surrounding local tissue cells, cause intracellular protein coagulation, necrosis and disintegration, while the formation of intravascular thrombus in the tumor further promotes the necrosis of tumor cells and fibrosis of necrotic foci to induce tumor coagulation and necrosis to achieve the inactivation of tumor foci and make tumor ablation; such as anhydrous alcohol, glacial acetic acid, hydrochloric acid, etc. Temperature ablation: This kind of treatment destroys tumor with the energy generated by temperature, including heat and freezing; Heat: It generates heat energy through equipment and instruments with different principles, and heats up the tissue by thermalization effect, the accumulation of heat energy exceeds the tolerance of cells and causes protein denaturation in cells, lipid layer dissolution, cell membrane destruction and coagulative necrosis of tissue cells, when the heat reaches 80-90℃, it can effectively kill local tumor cells quickly. When the heat reaches 80-90℃, it can effectively and quickly kill the local tumor cells, and at the same time, it can make the vascular tissue around the tumor coagulate to form a reaction zone, so that it cannot continue to supply blood to the tumor and help prevent the tumor metastasis. Such as radiofrequency, laser, microwave, ultrasound focusing, etc. Cryopreservation: It is the process of low temperature, freezing and thermal thawing to make ice crystals form in tumor cells, triggering expansion and deformation, cell dehydration and cell membrane structure change to destroy tumor; such as liquid nitrogen direct freezing, superconducting argon helium knife freezing, etc. Various in situ ablation techniques cause irreversible coagulative necrosis of tumor cells, and the antigenic change of tumor cells after necrosis becomes antigen to stimulate the body’s immune system, especially the coagulative necrosis caused by high temperature in tumor target tissues can play the role of high temperature solidification of retained tumor vaccine, enhance the body’s humoral and cellular immunity, and generate anti-tumor immune response.