What is radiotherapy?
Radiotherapy is a locoregional cancer treatment. It consists of using high frequency radiation to stop cancerous cells from multiplying. Irradiating cells has to be as precise as possible in order to spare nearby healthy tissues from the radiation as much as possible.
Radiotheraphy can be used on its own or often in combination with other methods, such as chemotherapy and surgery.
There are several radiotherapy techniques. External radiotheraphy is used the most often. The source of radiation is surrounds the patient externally. A machine near to the patient emits the rays, which go through the skin to reach the tumour. For smaller tumours, curietherapy can be employed. Here, the source of the rays is implanted directly inside the body. It introduces a large amount of ranium in the tumour, releasing radioactive rays over a short distance.
Finally, metabolic radiotherapy consists of administering a radioactive substance which sticks to cancerous cells to destroy them, either orally or through an intravenous injection.
Carrying out a radiotherapy session
The first radiotherapy session is dedicated to locating the area which needs targeting and calculating the required doses of radiation. A mark is tatooed on the skin which helps radiotherapists to identify the crucial point to target. During this session, the duration and frequency of future sessions is planned out.
Treatment sessions are usually quite short, between a quarter and half an hour. In general, routines follow one session per day for four or five days, over several weeks. Irradiation is invisible and painless for the patient. The treatment usually no longer requires hospitalisation and is carried out in an outpatient surgery.
Side effects of radiotherapy
Radiotherapy side effects are very common but often disappear at the end of a course of treatment. They vary depending on the patient, the irradiation area as well as the type and quantity of rays that are administered. Amongst some of the most common side effects there are:
- tiredness (asthenia) accompanied by a state of depression or loss of appetite
- headaches (cephalgia), nausea and vomiting
- sexual problems and fertility issues
- skin problems: red patchy skin, dryness and itching
- inflammatory reactions: oedema (swelling around the affected area) can appear over the course of treatment
- hair loss
- blood infections: this can occur when radiotherapy is combined with chemotherapy. This can happen because of a reduction in the number of white blood cells, red blood cells or platelets.
Some side effects are said to be delayed because they can appear several months after the end of treatment: reduced skin suppleness, mucus inflammation, lack of saliva, pains around the affected area and rosacea.