What does radiotherapy mean?
Radiotherapy is one of the three major treatments for cancer. It is a treatment method that irradiates the tumor with various kinds of different energies
to inhibit and kill cancer cells. Radiotherapy can be used alone or in conjunction with surgery and chemotherapy as part of comprehensive treatment to
improve the cure rate of cancer. A period of radiotherapy before surgery can reduce the size of the tumor
so that the patients who cannot be operated can have a chance to be operated.
For advanced cancer, palliative radiotherapy can be used to relieve compression and pain.
Radiotherapy can be divided into radical radiotherapy and palliative radiotherapy. The former has a higher dose and more thorough irradiation, and is used in early and partially advanced patients to eliminate primary
foci, possible residual foci after surgery, and some metastatic foci. The latter is used in late-stage patients and is mostly a stopgap measure. Doses are given as tolerated to improve symptoms, reduce pain, and prolong life. Individuals can also achieve radical results.
The total dose is determined by the doctor according to the nature of the tumor, its location, the stage of the disease, and the general condition.
The total dose is divided into 20 to 30 doses. The total dose is divided into 20-30 sessions, which are completed within 4-6 weeks. After accurate
positioning, markings are drawn on the body surface and the tumor is irradiated through the body surface. Therefore, the positioning markings such as the frame drawn on the body surface
should not be scrubbed off by yourself.
With the increasing incidence of tumors, more and more people have heard of radiotherapy, or there are people around who are undergoing radiotherapy. But most people don't know much about radiotherapy, what is radiotherapy?
Madame Curie is no stranger to everyone, it is because of the famous Nobel Prize in Physics winner discovered the radioactive element "radium", which began the precedent of radiotherapy, after countless physicists, medical scientists for more than a hundred years of continuous exploration and research, radiation therapy to make great strides in the development of the formation of a set of oncology, radiation physics, radiation biology, radiobiology, radiology, radiology, radiotherapy, radiotherapy, radiotherapy, radiotherapy, radiotherapy, radiotherapy, radiotherapy and radiotherapy, After more than one hundred years of continuous exploration and research by numerous physicists and medical doctors, radiotherapy has been greatly developed, forming a radiotherapy science integrating oncology, radiophysics, radiobiology and radiobiology, and it has become one of the three major methods of modern tumor treatment. 70% of the tumors need radiotherapy intervention, and radiotherapy is the first choice of many tumors, such as nasopharyngeal carcinoma, early laryngeal carcinoma, head and neck lymphoma, and basal cell carcinoma of the skin, etc, with remarkable curative effects.
Radiotherapy is the use of rays to kill tumor cells so as to achieve the purpose of curing tumors. Modern radiation therapy has a very high technological content, far from what people think "drawing lines" is so simple, not to mention what some people think "physical therapy". After the tumor is diagnosed and radiotherapy is needed, first of all, we need to do the pre-radiotherapy preparation, including CT, MRI examination, liver and kidney function, blood routine, ultrasound, chest X-ray, etc. The doctor will determine the scope of radiotherapy according to the imaging examination, clinical examination and pathological examination, select the type of rays and irradiation dose, and use the radiotherapy treatment planning system to formulate the radiotherapy plan, such as the angle and direction of ray projection, to make sure that the irradiated target area is included within 90% of the isodose line, and at the same time, the irradiated target area is included within the 90% of the isodose line. 90% of the dose line, and at the same time try to make the important tissues and organs are not or less damaged by the radiation. The technician then delivers the radiation, and in the course of treatment, the treatment plan is continuously improved according to the tumor regression. The designation of the radiation treatment plan for implementation often involves knowledge of oncology, imaging, physics and biology, and the equipment required is highly sophisticated, such as simulators, computerized radiation treatment planning systems, network systems, linear gas pedals, Co60 treatment machines, X-ray treatment machines, and so on. Any tissue and organs have a specific tolerance to radiation, the radiation dose exceeds its tolerance, it will trigger a series of radiation complications, and radiation late damage can occur after decades, seriously affecting the quality of life of the patient, so the determination of the radiation dose must be carried out under the guidance of radiation therapy professionals.
2. The mechanism of radiotherapy
What is radiotherapy Radiotherapy is radiation therapy, which refers to the use of rays to eliminate lesions. Radiotherapy, as an important means of treating malignant tumors, can produce good results for many cancers.
However, radiotherapy can produce many toxic side effects such as radiation dermatitis, radiation esophagitis, and loss of appetite, nausea, vomiting, abdominal pain, diarrhea, or constipation, etc. The use of traditional Chinese medicine and chemotherapy can not only effectively eliminate these toxic side effects, but also increase the radiosensitivity of the cancer cells, and help the radiation to completely kill the cancer cells. Radiotherapy is physical therapy.
Since the discovery of X-rays and radium at the end of the 19th century, the treatment of malignant tumors with radioactivity has had a remarkable development. At present, the commonly used radiotherapy can be divided into two kinds: external and internal; the former applies X-ray therapy machine, cobalt 60 therapy machine or neutron gas pedal for treatment, and the latter applies radionuclide for treatment.
Radiotherapy is to irradiate the cancerous tissues with X-ray, γ-ray, electron ray and other radiations, which can kill and destroy the cancerous tissues in the largest amount due to the biological effect of the radiations and make them shrink. This kind of therapy, which utilizes the lethal effect of radiation on cancer cells, is the same as surgical therapy as local therapy because the sufficient radiation dose only has therapeutic effect on the irradiated area.
Since radiotherapy is the best expected outcome for cancer treatment, improvement of symptoms, and prolongation of life, it is self-evident that it is also an indication for radiotherapy. It is clear that the sensitivity of cells to radiation is highest during the division phase and lowest during the DNA synthesis phase.
Radiotherapy does not so much damage the surrounding normal tissues, but only gives a large number of killings to the abnormally proliferating cancer to make it shrink, while the organism once again exerts the greatest possible regulatory function. Recently, in order to affect the surrounding normal tissues as little as possible, the method of irradiating the lesion from multiple directions has been adopted; this therapy is divided into radical irradiation, palliative irradiation, and radiation therapy combined with surgery.
Currently, in addition to the use of high-energy X-rays and gamma rays, high-energy particle rays are being used for cancer radiotherapy. It is expected that this method will play a more important role in radiation therapy in the future.
The development of radiation therapy has a history of only 80 years, but it is developing rapidly, from X-ray machines to ultrahigh-pressure devices, and the current acceleration is constantly improving and updating, and the emergence of proton rays, negative π mesons and other special radiotherapy. Current radiotherapy techniques: external irradiation, intracavitary and intertissue irradiation for brachytherapy, stereotactic radiation, and "metabolic" irradiation.
External irradiation: X-ray machines, the original therapeutic technique of radiotherapy, are still used to a small extent. Drill and brilliant radiation therapy machines are used to treat tumors with rays produced by the decay of radionuclides.
Linear gas pedals, which produce high-energy X-rays and electron rays are available to treat different tumors. Fast neutron rays, negative meson and proton gas pedals, which are more specialized in terms of therapeutic techniques and biological effects.
Brachytherapy: Radionuclides that can produce rays are used in different ways to get as close as possible to the tumor to increase the tumor dose. Stereotactic radiation: γ-knife, X-knife through the computerized treatment planning and control of multi-directional rotational radiation to improve the dose of the treatment area.
Radiotherapy is a complex, broad-based knowledge of the discipline, the basis of which includes: radiophysics, radiobiology, oncology, clinical radiotherapy technology, known as the four pillars, intended to be indispensable. In addition to this, all clinical disciplines have knowledge closely related to oncology.
Radiotherapy has been one of the indispensable means of tumor treatment. In all malignant tumors, radiotherapy is needed in 60%~70% of patients, and many tumors are cured by radiotherapy, such as: oropharynx, root of tongue, tonsil cancer is cured by radiotherapy in 37%~53%, maxillary sinus, nasal sieve sinus cancer is cured in 38%~40%, early tongue, nasopharyngeal, and cervical cancers are cured in 86%~94%, early esophageal cancers are cured in 80%~16%, early rectal and laryngeal cancers in 8~16%, and early rectal and laryngeal cancers are cured in 80~97%, and early rectal and laryngeal cancers in 8~16%, abroad. In the early stage of esophageal cancer, 80% and middle and late stage of esophageal cancer, 8%~16%, and in the early stage of rectal cancer and laryngeal cancer in foreign countries, 80%~97%, etc. Therefore, radiotherapy has an important value in the treatment of tumor.
The scope of radiotherapy: (1) purely curative tumors: nasopharyngeal cancer, early laryngeal cancer, early oral cancer, paranasal sinus cancer, Hodgkin's disease, medulloblastoma, basal cell carcinoma, lung cancer, esophageal cancer and so on. (2) Combining with chemotherapy to treat tumors: small cell lung cancer, middle and advanced malignant lymphoma, etc.
(3) Combined treatment with surgery: maxillary sinus, ear, nose and throat cancer, glial neuroblastoma, lung cancer, thymoma, gastrointestinal tract cancer, soft tissue sarcoma and so on. There are planned preoperative radiotherapy, intraoperative radiotherapy and postoperative radiotherapy.
(4) Palliative radiotherapy: pain-relieving radiotherapy for bone metastases, radiotherapy for brain metastases, and treatment of palliative effects of severe local comorbidities caused by advanced tumors. Due to the early years of radiotherapy service without experience in the early stage, the radiation dose, the biological effect is not good to grasp, and caused by radiation damage such as ulcers, radiation sickness, reaction to the heavy, so to many people left a radiation on the human body contact with the fear, has been so far some people still harbor this kind of mentality.
At present, radiotherapy has been developed to the stage of molecular biology research, and the extensive use of computer-controlled high-tech therapeutic equipments. A large amount of experience has become a standardized theory, and the reaction of radiotherapy in the early years seldom occurs, and it is possible to fully anticipate the degree of side effects of the given treatment volume and scope, so the therapeutic contribution of radiotherapy to the tumors and the control of the side effects do not have to be taken into account. Possibility of retreatment for recurrent cancer: For example, if laryngeal cancer or esophageal cancer recurs after treatment, surgery should be chosen as much as possible to avoid the aggravating damage of retreatment with radiotherapy.
And most of the tumors recur after treatment, the chance of surgery is very little, so radiotherapy can be done in a small range for the tumor, which can still alleviate the condition, such as nasopharyngeal carcinoma, there is still a small part of it can be cured in the second course of treatment. However, the principle of the second course of radiotherapy should be different from the scope of the first course of treatment, i.e., it is no longer irradiation for prevention in a large area, and it is only for the main purpose of radiotherapy for the tumor area, and the dose should not be too high. The second course of radiotherapy can also be used with surgical local excision, which can reduce the amount of radiation, or external irradiation of a part of the tumor plus a certain amount of brachytherapy to reduce the dose to normal tissues and avoid damage to normal tissues.
[Side effects of radiotherapy Although radiotherapy and chemotherapy have many advantages, there are also many disadvantages. Radiotherapy can not reduce the toxic effects of chemotherapy, chemotherapy can not reduce the damaging effects of radiotherapy, such as chemotherapy inhibition of the whole body of the bone marrow, radiotherapy also produces local myelosuppression, the patient is often due to myelosuppression of the blood phase is low and can not continue the treatment.
When doing radiotherapy for thoracic tumors, patients with radiation pneumonitis or pulmonary fibrosis after chemotherapy.
3. What is radiotherapy
Radiotherapy is radiation therapy, which refers to the use of rays to eliminate lesions. Radiotherapy, as an important means of treating malignant tumors, can produce good results for many cancers.
However, radiotherapy can produce many toxic side effects such as radiation dermatitis, radiation esophagitis, and loss of appetite, nausea, vomiting, abdominal pain, diarrhea, or constipation, etc. The use of traditional Chinese medicine in conjunction with chemotherapy can not only effectively eliminate these toxic side effects, but also increase the radiosensitivity of cancer cells, and help the radiation to completely kill the cancer cells. Radiotherapy is physical therapy.
Since the discovery of X-rays and radium at the end of the 19th century, the treatment of malignant tumors with radioactivity has had a remarkable development. At present, the commonly used radiotherapy can be divided into two kinds, in vitro and in vivo, the former applying X-ray treatment machine, cobalt 60 treatment machine or neutron gas pedal for treatment, and the latter applying radionuclide for treatment.
Radiotherapy is to irradiate the cancerous tissues with X-ray, γ-ray, electron ray and other radiations, which can kill and destroy the cancerous tissues in the largest amount due to the biological effect of the radiations and make them shrink. This kind of therapy, which utilizes the lethal effect of radiation on cancer cells, is the same as surgical therapy as local therapy because the sufficient radiation dose only has therapeutic effect on the irradiated area.
Since radiotherapy is the best expected outcome for cancer treatment, improvement of symptoms, and prolongation of life, it is self-evident that it is also an indication for radiotherapy. It is clear that the sensitivity of cells to radiation is highest during the division phase and lowest during the DNA synthesis phase.
Radiotherapy does not so much damage the surrounding normal tissues, but only gives a large number of killings to the abnormally proliferating cancer to make it shrink, while the organism once again exerts the greatest possible regulatory function. Recently, in order to affect the surrounding normal tissues as little as possible, the method of irradiating the lesion from multiple directions has been adopted; this therapy is divided into radical irradiation, palliative irradiation, and radiation therapy combined with surgery.
Currently, in addition to the use of high-energy X-rays and gamma rays, high-energy particle rays are being used for cancer radiotherapy. It is expected that this method will play a more important role in radiation therapy in the future.
The development of radiation therapy has a history of only 80 years, but it is developing rapidly, from X-ray machines to ultrahigh-pressure devices, and the current acceleration is constantly improving and updating, and the emergence of proton rays, negative π mesons and other special radiotherapy. Current radiotherapy techniques: external irradiation, intracavitary and intertissue irradiation for brachytherapy, stereotactic radiation, and "metabolic" irradiation.
External irradiation: X-ray machines, the original therapeutic technique of radiotherapy, are still used to a small extent. Drill and brilliant radiation therapy machines are used to treat tumors with rays produced by the decay of radionuclides.
Linear gas pedals, which produce high-energy X-rays and electron rays are available to treat different tumors. Fast neutron rays, negative meson and proton gas pedals, which are more specialized in terms of therapeutic techniques and biological effects.
Brachytherapy: Radionuclides that can produce rays are used in different ways to get as close as possible to the tumor to increase the tumor dose. Stereotactic radiation: γ-knife, X-knife through the computerized treatment planning and control of multi-directional rotational radiation to improve the dose of the treatment area.
Radiotherapy is a complex, broad-based knowledge of the discipline, the basis of which includes: radiophysics, radiobiology, oncology, clinical radiotherapy technology, known as the four pillars, intended to be indispensable. In addition to this, all clinical disciplines have knowledge closely related to oncology.
Radiotherapy has been one of the indispensable means of tumor treatment. In all malignant tumors, radiotherapy is needed in 60%~70% of patients, and many tumors are cured by radiotherapy, such as: oropharynx, root of tongue, tonsil cancer is cured by radiotherapy in 37%~53%, maxillary sinus, nasal sieve sinus cancer is cured in 38%~40%, early tongue, nasopharyngeal, and cervical cancers are cured in 86%~94%, early esophageal cancers are cured in 80%~16%, early rectal and laryngeal cancers in 8~16%, and early rectal and laryngeal cancers are cured in 80~97%, and early rectal and laryngeal cancers in 8~16%, abroad. In the early stage of esophageal cancer, 80% and middle and late stage of esophageal cancer, 8%~16%, and in the early stage of rectal cancer and laryngeal cancer in foreign countries, 80%~97%, etc. Therefore, radiotherapy has an important value in the treatment of tumor.
The scope of radiotherapy: (1) purely curative tumors: nasopharyngeal cancer, early laryngeal cancer, early oral cancer, paranasal sinus cancer, Hodgkin's disease, medulloblastoma, basal cell carcinoma, lung cancer, esophageal cancer and so on. (2) Combining with chemotherapy to treat tumors: small cell lung cancer, middle and advanced malignant lymphoma, etc.
(3) Combined treatment with surgery: maxillary sinus, ear, nose and throat cancer, glial neuroblastoma, lung cancer, thymoma, gastrointestinal tract cancer, soft tissue sarcoma and so on. There are planned preoperative radiotherapy, intraoperative radiotherapy and postoperative radiotherapy.
(4) Palliative radiotherapy: pain-relieving radiotherapy for bone metastases, radiotherapy for brain metastases, and treatment of palliative effects of severe local comorbidities caused by advanced tumors. Due to the inexperience of radiotherapy in the early years of the early stage, the radiation dose, the biological effect is not good to grasp, and caused by radiation damage such as ulcers, radiation sickness, reaction to the heavy, so that many people left a radiation on the human body contact fear, has been so far some people still harbor this kind of psychology.
At present, radiotherapy has been developed to the stage of molecular biology research, and the extensive use of computer-controlled high-tech therapeutic equipments. A large amount of experience has become a standardized theory, and the reaction of radiotherapy in the early years seldom occurs, and it is possible to fully anticipate the degree of side effects of the given treatment volume and scope, so the therapeutic contribution of radiotherapy to the tumors and the control of the side effects do not have to be taken into account. Possibility of retreatment for recurrent cancer: For example, if laryngeal cancer or esophageal cancer recurs after treatment, surgery should be chosen as much as possible to avoid the aggravating damage of retreatment with radiotherapy.
And most of the tumors recur after treatment, the chance of surgery is very little, so radiotherapy can be done in a small range for the tumor, which can still alleviate the condition, such as nasopharyngeal carcinoma, there is still a small part of it can be cured in the second course of treatment. However, the principle of the second course of radiotherapy should be different from the scope of the first course of treatment, i.e., it is no longer irradiation for prevention in a large area, and it is only for the main purpose of radiotherapy for the tumor area, and the dose should not be too high. The second course of radiotherapy can also be used with surgical local excision, which can reduce the amount of radiation, or external irradiation of a part of the tumor plus a certain amount of brachytherapy to reduce the dose to normal tissues and avoid damage to normal tissues.
[edit]Side effects of radiotherapy Although radiotherapy and chemotherapy have a lot of advantages, but there are also many disadvantages. Radiotherapy can not reduce the toxic effects of chemotherapy, chemotherapy can not reduce the damaging effects of radiotherapy, such as chemotherapy inhibit the whole body of the bone marrow, radiotherapy also produces local myelosuppression, the patient is often due to myelosuppression of the blood phase is low and can not continue the treatment.
When doing radiotherapy for chest tumors, patients after chemotherapy had radiation pneumonitis or pulmonary fibrosis, radioactivity.
4. Radiotherapy is
What is chemotherapy? Chemotherapy is a therapeutic way to use chemical drugs to kill tumor cells, inhibit the growth and reproduction of tumor cells and promote the differentiation of tumor cells. It is a systemic treatment for primary foci, metastatic foci and subclinical metastatic foci.
The disadvantage is the poor selectivity of chemotherapeutic drugs, in the therapeutic effect, often appear different degrees of toxic side effects; chemotherapy process of physical debility, mental depression, sweating, white blood cells and platelets drop, or even red blood cells, blood pigment drop ensue, and even force patients to stop treatment, the use of traditional Chinese medicine and chemotherapy with the treatment can be effective in eliminating these toxic side effects, and at the same time, with chemotherapy to form a synergistic effect, increase the chemotherapy, and the chemotherapy can be effective in eliminating these toxic side effects. The use of Chinese medicine with chemotherapy can effectively eliminate these toxic side effects, and at the same time, form a synergistic effect with chemotherapy, increasing the therapeutic effect of chemotherapy. What is radiotherapy? Radiotherapy is one of the three major treatments for cancer.
Radiotherapy is a treatment that uses different kinds of energy to irradiate tumors in order to inhibit and kill cancer cells. Radiotherapy can be used alone or in combination with surgery and chemotherapy as part of a comprehensive treatment to improve the cure rate of cancer.
A period of radiotherapy before surgery can reduce the size of the tumor, and then patients who could not be operated on can have the opportunity to be operated on. For advanced cancer, palliative radiotherapy can be used to relieve pressure and pain.
Radiotherapy can be divided into radical radiotherapy and palliative radiotherapy. The former has a higher dose and more thorough irradiation, and is suitable for early and some advanced patients to eliminate the primary foci, possible residual foci after surgery, and some metastatic foci.
The latter is for advanced patients and is mostly a stopgap measure. Doses are given as tolerated to improve symptoms, reduce pain, and prolong life.
Individuals can also achieve radical results. The total dose is determined by the doctor according to the nature of the tumor, its location, the stage of the disease and the general condition.
The total dose is divided into 20-30 sessions, which are completed within 4-6 weeks. After accurate positioning and marking of the body surface, the tumor is irradiated through the body surface.
Therefore, do not scrub off the positioning markings such as the frame drawn on the body surface.
5. What is precision radiotherapy
The progress of radiotherapy has achieved a milestone in the last 20 years, which is highlighted by the popularization of precision radiotherapy in clinical practice.
Precision radiotherapy is a concrete result of the application of modern technology in the treatment of tumors. It involves new imaging technologies, such as CT, PET/CT, and magnetic **** vibration data, which allow doctors to accurately outline the boundaries of the tumor, the location of metastatic lymph nodes, and the boundaries of the surrounding normal tissues.
This is a very demanding task for the radiotherapist, who must not miss tumor tissue or damage too much normal tissue. These images are entered into a computerized treatment planning system (TPS), which is actually an advanced electronic computer system.
The radiotherapist then determines how much of the tumor should be irradiated, in how many doses, and how much normal lung tissue, heart, and spinal cord will be harmed to further optimize the treatment plan, and can modify any part of the plan that is not satisfactory. The radiotherapist has to carefully consider the movement of the tumor in the body with breathing and heartbeat during radiotherapy, as well as the y-error of each treatment ***, so that there can be no "centimeter-level" error in these parts of the treatment.
^ The patient needs a special air cushion device to hold the *** in place, and the laser is positioned on the skin before irradiation. So it's very precise, it's called precision radiotherapy.
Without the progress of imaging equipment, without the innovation of electronic computer functions, without the development and progress of radiotherapy machines and equipment, to achieve precision radiotherapy can only be a pipe dream. At present, the three-dimensional conformal radiotherapy (3D~CRT), X-knife or 7-knife, conformal intensity-modulated radiotherapy (IMRT), spiral tomotherapy (TOMO), image-guided radiotherapy (IGRT), radio wave knife and other technologies commonly used in the clinic belong to the precision radiotherapy.
The core technology is that the tumor target area is irradiated with appropriate dose, while the dose to the surrounding tissues, especially the vital organs and tissues, is below the safety line. Therefore, precision radiotherapy is the latest progress of modern radiotherapy and the development trend of radiotherapy both at home and abroad.