Radiotherapy uses ionizing radiation - forming free radicals in the tissue through which it passes. The effectiveness of therapy is based on the harmful effects of radiation on cells and cell nuclei.
X-rays, radium or cobalt are rarely used to fight cancer (chloniaki) cells, and more often radiation generated by so-called linear accelerators.
The total dose of radiation that destroys cancer cells is given in many sessions (so-called fractionated doses) to protect the healthy ones as much as possible.
- Before starting radiation therapy, based on diagnostic tests: computed tomography, magnetic resonance imaging or positron emission tomography combined with computed tomography (PET-CT), the doctor determines the irradiation area, i.e. the tumor and, if necessary, adjacent lymph node packs.
Then, the medical physicist using computer systems selects the method of treatment for a given patient, but also radiation energy to ensure that the assigned dose is deposited in the indicated area, and at the same time to maximally protect other healthy organs - explains Dr. Phys. Marcin Dybek from Affidea International Center of Oncology.
The use of radiation therapy in cancer
So what is the point of such treatment? In healthy and diseased cells exposed to radiation, there are great changes in their structure and functioning. So-called radiation toxins that destroy the proteins that each cell is made of.
All this leads to their annihilation - regardless of whether they are healthy or cancerous cells. But between radiation sessions, healthy cells can regenerate and repair damage that occurs in them.
Cancer cells can't do it as well as healthy. When they get another dose of rays, they die. This is a simplified mechanism of cancer treatment by radiation therapy.
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