According to the treatment area, tumor thermotherapy is mainly divided into systemic thermotherapy and local thermotherapy. Systemic thermotherapy is seldom used in clinical practice because of its complicated procedures, many complications and large damage to patients. Local heat therapy is also divided into microwave heat therapy, ultrasonic heat therapy and radiofrequency heat therapy according to its principle. At present, the deep tumor phased-array thermal therapy system (BSD2000, USA), high-energy ultrasonic focused tumor treatment system (HIFUNIT9000, China) and tumor radiofrequency therapy machine (RITA1500X, USA) owned by the Department of Oncology of Beijing Hospital of Traditional Chinese Medicine all belong to local thermal therapy, and the main roles and characteristics of these three thermal therapies are compared. 1. Similarities They all belong to physical therapy, and all of them treat tumor by heating method. These three methods can be treated alone or combined with radiotherapy, chemotherapy and interventional therapy to play a synergistic effect. (1) Different ways of heat energy generation HIFU uses ultrasound as the energy source and utilizes its penetrating and focusable nature to focus low-energy ultrasound outside the body on the lesion in the body and generate instant high temperature at the focal point to kill tumor tissues. BSD2000 deep heat therapy uses electromagnetic wave as energy source, which penetrates the body through radiation and focuses on the tumor site in the body to generate heat. Tumor RF generates heat by causing ions in tumor tissues to oscillate and rub through alternating current. (2) The temperature of treatment target area (tumor lesion) is different BSD2000 deep heat therapy can make the temperature of tumor target area reach 41.5℃~43.5℃. The temperature of HIFU treatment area is ≥65℃. The temperature of radiofrequency treatment area is between 90~100℃. (3) Different ways and effects of tumor destruction BSD2000 deep heat therapy can inhibit tumor cell proliferation activity and induce tumor cell apoptosis, and its therapeutic effect is not completely reflected in the recent changes of tumor size and texture, but mainly in the improvement of symptoms and the stability and improvement of quality of life; it has a sensitizing effect in combination with radiotherapy and can enhance the killing effect of the latter on tumor. HIFU can cause coagulative necrosis of tumor tissues, and echogenic changes of tumor and reduction of intra-tumor blood vessels can be observed after treatment. Radiofrequency treatment can cause irreversible necrosis of tumor cells, and the recent effect is the reduction of tumor density and blood flow in the tumor, and the tumor shrinkage or even disappearance can be observed in the long term. (4) Different trauma to human body Among the above three thermal therapy modalities, BSD2000 deep thermal therapy and HIFU are non-invasive treatments with less side effects on patients and can be performed in outpatient clinics. Radiofrequency therapy is minimally invasive and requires percutaneous puncture under CT or ultrasound guidance after local anesthesia, but the risk is significantly lower than that of surgery, and most patients tolerate it well and can generally be discharged after 1~3 days of postoperative observation. (5) Different Applicable Population In theory, tumor patients with combined heart, liver, kidney, brain, lung and other organ failure or with coagulation mechanism disorders and those who cannot cooperate with treatment are not suitable for thermal therapy. BSD2000 deep heat therapy and HIFU are suitable for patients with advanced recurrent metastases or inoperable tumors, either alone or in combination with radiotherapy and chemotherapy. Among them, the following conditions should be listed as contraindications for HIFU treatment: ① tumors for which the built-in ultrasound probe cannot complete localization; ② the water bladder membrane of the treatment machine cannot adequately couple with the skin of the treatment site; ③ there are metals or other objects on the treatment channel that make the ultrasound waves cannot pass through. However, the BSD2000 deep heat therapy can still be applied. Therefore, the latter is more widely adapted to the population. Radiofrequency therapy is suitable for tumors with high requirements for treatment precision and treatment effect, so both advanced and early stage tumors are its indications. Its destructive effect on tumors is the best among the three means, and for some small liver cancers and peripheral lung cancers, it can even achieve the effect of surgical radical treatment.