Thanks to modern technologies, radiotherapy is becoming more precise, i.e. more effective and more gentle. Radiotherapy is a collective term for a host of different irradiation methods. Thus, percutaneous radiotherapy, intraoperative radiotherapy, brachytherapy or Cyberknife can be used, for example.
Radiotherapy is an important treatment method for cancer. Cancer cells and malignant tumours can be specifically targeted and killed off by administering localised x-ray radiotherapy, gamma radiotherapy or partial radiotherapy (electons, protons, neutrons). The principle of the different types of radiotherapy is the same: the atoms and molecules in the tumour cells are changed (ionised) by the radiotherapy. This is designed to kill off the cells. Radiotherapy is used on half of all cancers. Radiotherapy is often combined with other treatment methods such as chemotherapy and immunotherapy.
What preparations are carried out before the procedure?
Firstly, evaluations are made to determine which radiation method is the most suitable form of treatment. The stage of the cancer is also recorded and the cancer cells are examined to determine whether they are sensitive to radiation. These evaluations are undertaken by an interdisciplinary team consisting of oncologists and radiologists.
The dosage of the radiotherapy is precisely calculated before the actual radiotherapy takes place. The trick is to find the minimum dose which conclusively destroys the tumour cells but is as gentle as possible on the healthy tissue. The correct position for the radiotherapy is determined with the help of x-ray images. A support mattress is often used so that the patient can undergo every radiotherapy session in exactly the same position. It is a mattress which adjusts itself to the person's body position. When the correct position is found, the mattress is fixed with the body imprint. Thus, the patient can always put him or herself into the absolutely correct position.
How is the procedure performed?
Several sessions are usually necessary for the radiotherapy to be successful. The first session takes longer because the required adjustments are made. Depending on the type of tumour and cancer, one of the following types of radiotherapy is administered: percutaneous radiation, stereotactical radiotherapy, brachytherapy, intraoperative radiotherapy.
Percutaneous radiotherapy is the most common radiotherapy procedure. In the process, the radiotherapy is applied from outside the body through the skin into the tumour. With the modern instruments (linear accelerators), electrically powered parts are accelerated and focused exactly on the tumour. This radiotherapy procedure is used to combat breast cancer, for example.
Stereotactic radiotherapy is also known as Cyberknife. It is an extremely precise, robot-assisted percutaneous radiotherapy procedure. A compact, small radiotherapy instrument is mounted on a robotic arm which can always precisely focused with the help of x-ray and computer tomography images. With this technology, the radiotherapy can be undertaken at over one thousand different angles. Thanks to the robotic control, the exact radiotherapy position can be maintained continuously, even if the patient is breathing. The Cyberknife is used primarily patients with brain tumours and bone marrow tumours, as well as on those with pulmonary and liver metastases.
Brachytherapy is an radiotherapy procedure in which radioactive particles are inserted into the body. A distinction is made between the seed implantation procedure and the afterloading procedure.
During the seed implantation procedure, the radioactive particles are administered in the vicinity of the tumour under general anaesthetic, using a hollow needle. They remain in the body and have an effect as long as they remain radioactive. After around 20 days, half of the radiation dose is dispensed.
During the afterloading procedure, a needle or a tube (applicator) is inserted into the tumour tissue and fixed there. The irradiation device is attached to the needle or the tube. A thin wire is fed into the tumour tissue through the applicator and emits the required radiation dose for a short period. This procedure can be repeated many times and the patient can get up between each of the sessions. Brachytherapy is used primarily in patients with prostate cancer.
Intraoperative radiotherapy with an intrabeam offers an opportunity to irradiate the tumour while an operation is taking place. This technology is used primarily in patients with small cancerous tumours of the breast. After the surgical removal of the tumour, the surrounding tissue is directly irradiated. This makes targeted radiotherapy possible. As the radiotherapy does not take place through the skin, the rays do not damage the skin.
What is the success rate of this procedure?
Radiotherapy is an effective treatment for many cancers. The success rates depend on the stage of the cancer and the type of tumour. The risk of metastisation or the reoccurence of the tumour can often be reduced with the irradiation. Sometimes tumours which are too large for the surgery can be reduced in size with radiotherapy, making surgery possible.
What are the possible complications and risks of this procedure?
Despite the fact that radiotherapy is becoming progressively more precise and more gentle, the irradiation itself should not be underestimated. Damage can appear locally in healthy tissue in the area where the radiotherapy was applied. In the process, certain organs react more sensitively than others. It can lead to redness on the skin, similar to that of a sunburn. If the head is irradiated, this can cause the patient's hair to fall out. However, it usually regrows after the radiotherapy. If radiotherapy is administered to the abdominal area, this can lead to digestive disorders, diarrhoea, nausea and a general feeling of discomfort. If radiation is administered in the area of the testicles or the ovaries, this can affect the recipient's ability to have children.
What happens after the treatment?
There is usually further treatment after the radiotherapy. Depending on the cancer, this can be chemotherapy, immunotherapy or hormone therapy. The progression of the cancer will be closely monitored and the success rate with regular check-ups.