Radiation therapy is the specialty of nuclear medicine that uses ionizing radiation to treat malignant tumors. Without a doubt, one of the main advantages of the development of nuclear energy.
When non-encapsulated radioactive sources are used, we talk about metabolic radiotherapy, which consists of injecting or having a relatively large dose of a radioactive substance in liquid form, so that it accumulates in the organ to be treated, where it acts by means of the radiation emitted on the tissues in contact with it, producing the desired effects of destruction of the tumor cells.
This type of therapy is used for the treatment of hyperthyroidism, thyroid cancer, bone metastases of prostate and breast tumors, and can be used alone or in association with other therapeutic means of medicine such as surgery or chemotherapy.
In the case of thyroid cancer, iodine-131 is used, because it is a gamma emitter, the patient is admitted to special units that have radio protection units and specialized medical staff. Once the patient has been discharged, a dosimetric control is carried out periodically to monitor and verify that, due to its low doses of gamma radiation, the patient can live with his family and the rest of the population.
Among the applications of radiotherapy can be mentioned the tele-therapy and brachytherapy
What is teletherapy ?
Teletherapy is a nuclear medicine radiotherapy technique in which the radioactive source is not in direct contact with the tumor being treated.
Among the gamma emitting sources used, the encapsulated source of cobalt-60, contained in the so-called cobalt pump, stands out, which prevents radiation from escaping except for an orifice that provides directed radiation.
Teletherapy produces high energy radiation (1.2 MeV) capable of irradiating large deep-located tumors. Teletherapy can also be administered with emitting sources of electronic and neutron beams.
Purpose of treatment by teletherapy
There are different nuclear medicine treatments using teletherapy focused on achieving different objectives:
- Radical or curative treatment. In radical therapy, the purpose of treatment is to destroy the tumor and cure the patient.
- Palliative medical treatment. The purpose of palliative care is mainly to reduce the signs of the tumor induced by the disease (pain relief, bleeding related to the tumor), although we know that the disease is no longer curable. The essential purpose of palliative care is mainly to allow patients to live as long as possible and with a good quality of life, although cancer cannot be destroyed.
- Preoperative treatment. The purpose of preoperative irradiation is to irradiate in order to reduce the tumor before the surgery itself.
Brachytherapy is a nuclear medicine radiotherapy technique in which the radioactive source is in direct contact with the tumor.
When the radioactive material plates are placed on the tumor area, it is called superficial brachytherapy, if this source is temporarily introduced into the patient, in natural cavities, it is referred to as intracavitary brachytherapy and encapsulated sources of cesium-137 are usually used, and if they are placed Radioactive sources in certain tissues is known as interstitial brachytherapy.
One of the problems of this therapy, also known as Curietherapy, is the possible unnecessary exposure of the patient and the healthcare staff to radiation from the sources, so the source will be placed in the correct position in the patient, and the staff The utility will use remote control controls to prepare, transport and handle radioactive sources.