Medical scientists have found that normal tissues of the human body dilate blood vessels, accelerate blood flow and dissipate heat faster when the body temperature rises. Due to this regulatory effect of the body, it is guaranteed that when the body temperature rises, even when the body temperature reaches 41.5-43℃, the tissue damage is not big and can be repaired. However, this is not the case with tumor tissue, where blood vessels within the tumor have abnormal morphology, are messy and twisted, easily deformed by pressure, and form thrombi or embolism. In addition, the blood vessels within the tumor are mostly composed of monolayer cells, which are fragile and easily broken. As these neovascularization is underdeveloped and malformed blood vessels, they lose self-regulation after being heated, and the veins can not accelerate reflux, local blood stagnation in the tumor, and the blood flow is only 1% to 15% of normal tissue, resulting in difficulty in heat dissipation of tumor tissues, and the temperature rises. The temperature of malignant tumor tissue is often higher than the temperature of adjacent normal tissue by 8~10℃. For the same local heating, if the temperature of normal tissue rises to 40°C, then the temperature inside the tumor can rise to about 48°C, which is hot enough to make the tumor cells die, while the normal tissue is not damaged. In general, the larger the tumor, the lower the blood flow, and the better the results of thermal therapy.
A large number of experiments and clinical trials have proved that tumor cells are inhibited in 39℃ and 40℃, and their activity is inhibited, and the tendency of apoptosis is increased; in 40℃～42℃, the tumor cells will be seriously damaged, and can die in a relatively short period of time. Tumor thermotherapy instrument uses the working principle of microwave dipole lens antenna, which gathers the weak directional electromagnetic wave of radiation source into sharp directional electromagnetic wave beam, so as to increase the power density of incident microwave and cluster the microwave, so as to increase the effective heating depth of microwave during the treatment, and it can raise the body temperature to the effective therapeutic temperature in a shorter period of time, and when the radiator irradiates on the position of containing tumor tissues, the temperature of the normal tissues reaches When the radiator irradiates on the location containing tumor tissue, the temperature of normal tissue reaches 41℃-43℃ and maintains for a certain period of time. Due to the difference in vascular structure and microcirculation between normal tissue and tumor tissue, the temperature of tumor tissue is higher than that of the surrounding normal tissue by 3~7℃ when heated. Due to the difference in vascular structure and microcirculation between normal tissues and tumor tissues, the temperature of tumor tissues is 3~7℃ higher than that of the surrounding normal tissues when heated. Therefore, while killing the tumor cells, it will not cause damage to the normal tissues around the tumors, so as to achieve the purpose of treating the tumors without any damage, side effects and pain. Tumor thermotherapy instrument is based on this principle and was born.