Overview of radiation oncology:Radiation oncology is an independent discipline which combines many subjects with high technology. About 70%
Overview of radiation oncology:
Radiation oncology is an independent discipline which combines many subjects with high technology. About 70% of cancer patients need to be treated with radiation therapy to achieve the purpose of cure or relieve symptoms and improve quality of life. At present, laryngeal cancer, rectal cancer and nasopharyngeal carcinoma early stage or tumor after radiotherapy after five years, the cure rate reached more than 80-95%, each stage of nasopharyngeal carcinoma, cervical cancer, He Jie Hodgkin's lymphoma and prostate cancer five years survival rate of up to 40-50%. Radiotherapy combined with surgery, chemotherapy and other therapies, can make 40% of all types of cancer for clinical cure. The remission rate of refractory pain caused by radiotherapy for malignant tumor can reach 80-90%, and it can achieve the purpose of local control of tumor in varying degrees. In recent years, with the theory of comprehensive treatment of tumor view is identification and clinical implementation, development and improvement of equipment and technology of radiotherapy and radiotherapy, especially conformal intensity-modulated radiotherapy clinical application of three-dimensional technology, further expand the range of indications of radiotherapy, more improve the efficacy of radiotherapy. Radiation therapy has become one of the most important and effective means in the treatment and control of tumors.
Radiation oncology, like all other disciplines, is constantly evolving and improving, and will continue to contribute to the maintenance of human health for a long time to come.
Objective of tumor radiotherapy technology
To maximize the radiation dose to lesion (target area), at the same time to kill tumor cells and the surrounding normal tissues and organs less susceptible to or from unnecessary radiation, so as to be protected, this is the pursuit of the goal of tumor radiotherapy.
Technical classification of radiotherapy:
Characteristics of conventional radiotherapy:
1 the irregular shape of the radiation field in the two-dimensional direction is obtained by using a regular shape or a lead mode occlusion method.
2 the dose distribution in each field was uniform
Advantages: equipment, technical requirements are low, the operation is relatively simple, mostly used for preoperative and postoperative radiotherapy of malignant tumors.
Lack of irradiation and tumor shape: shape in three-dimensional direction of the radiation field is not entirely consistent, including the normal tissue is more sensitive to tissue and vital organs surrounding the tumor cases is not suitable.
Two, precision radiotherapy (IMRT)
Technical characteristics of precision radiotherapy:
1 what is conformal? In the three-dimensional direction, a plurality of irradiation fields and a plurality of angles are used for irradiation, and the cross section shape of each irradiation field is consistent with the shape of the corresponding section of the tumor.
2 what is intensity? According to the situation of the tumor, the CT scan, the reverse three dimensional treatment planning system was designed to change the dose distribution in order to make the surface of the tumor and the internal points evenly distributed.
Advantages: it can improve the radiation dose to the tumor, effectively kill tumor cells, but also can more effectively protect the normal tissues and organs, improve the curative effect, improve the quality of life, and to expand the scope of indications of radiotherapy.
Disadvantages: it is necessary to use spiral CT scanning three-dimensional imaging, simulation positioning system and reverse three-dimensional treatment planning system, the cost is more expensive, complex technology, strict body repetition, the operation is difficult.