Synonyms
- Radiooncology
- Irradiation
- Tumour irradiation
High-energy photon and particle radiation belong to the category of ionizing radiation. When such radiation hits matter, such as water, energy from the radiation is transferred to the atoms or molecules of the water, where it leads to ionization. The resulting charged particles are in turn very reactive and can change neighboring molecules.
The types of radiation differ greatly in the way the energy is transferred and can be used therapeutically to a greater or lesser extent through these properties. The most commonly used rays in the therapeutic field are high-energy X-rays and electron beams. After entering the tissue, for high-energy X-rays the energy output in the tissue increases to a certain depth and then slowly decreases.
In the case of electron radiation, the area of maximum energy transfer is very close to the surface and drops rapidly at depth. Electron beams are therefore more suitable for the treatment of processes close to the surface and high-energy X-rays for deeper layers. The aim of radiation therapy in humans is to damage the existing tumor cells through the energy transfer in such a way that they subsequently die.
The resulting reactive water molecules lead to changes or damage to the DNA of the cell. The DNA contains the information for controlling the metabolic processes of the cell. If critical damage occurs in this molecule, the tumor cell can no longer control its vital processes and can no longer divide.
Ultimately, this leads to the death of the tumor cell and, ideally, the entire tumor. The goal of any radiation therapy must therefore be to transfer the highest energy transfer of the radiation into the area of the tumor. In order to achieve this, modern computer-controlled treatment facilities are used today.
These help to obtain a very precise prediction of the dose distribution in the body. Would you like to know which effects can occur as a long-term effect after radiation?