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Radiotherapy treatment

Radiotherapy treatment


The first consultation

Physical stage
What happens during a radiation session?
The long and agonising wait
After treatment
Transport and accommodation
Answers to your questions


Before the first visit, your file will be discussed and analysed at a multi-disciplinary meeting, which your radiotherapist-oncologist will attend. Otherwise, your data will be sent to your radiotherapist-oncologist to give him the information necessary to determine your course of treatment, in discussion with your treating physician and the other specialists taking care of you. The radiotherapist-oncologist will ask you about your health problems and those of your immediate family and your lifestyle, in order to discuss the most suitable treatment with you. If you agree to the treatment in principle, the doctor will explain things to you in detail.



The timetable suggested to you at the start of your treatment is very important, both for you and for the team taking care of you. It is not a good idea to alter the pattern. If anything unexpected occurs, you must inform your doctors as soon as possible. Interruptions to your treatment must be avoided as far as possible, and must in any case be approved by your radiotherapist-oncologist. Of course if an X-ray machine breaks down, for example, the treatment will have to be temporarily interrupted. It is currently believed that interruptions of no more than 4-5 days will not reduce the efficacy of the treatment, but this will vary greatly depending on the type of tumour treated. Do not hesitate to ask your doctor on this subject.



Simulation is the first stage of your treatment. It is prepared using a “simulator”, which allows us to mark out and clearly define the part of the body requiring the treatment. The reference points are drawn on your skin with a special red fuchsin dye, although sometimes, small tattooing points are used.
A CT-scan or PET CT is often necessary, to determine the region to be treated and ensure added precision. During this examination, extremely accurate X-ray plates of the region to be treated are taken, in a position identical to that of your treatment. Usually, this examination is carried out at a separate appointment.
A second simulation will follow 7-10 days later, to confirm the reference points marked out on the skin, before the treatment proper is started.
Simulation is essential to make your treatment proceed smoothly. Usually, it lasts 30 minutes to 1 hour, although this can sometimes seem long. You will always be informed if simulation is not required for any particular reason, or if we use certain accessories during the simulation process. Your treatment will begin shortly afterwards, under the supervision of the radiotherapist-oncologist.



Computers analyse and calculate the data obtained during simulation. The radiotherapist-oncologist and radiation physicist will work together to plan your treatment, the distribution of radiation doses, the size of the areas to be irradiated, and their number and position in space. They then use the computer to verify whether the treatment plan is suitable for your personal situation.



The treatment may last for anything between 1 day and 7 weeks. Its duration varies depending on how your condition progresses, and depends on your reactions. You should not worry if the specialists decide to alter the duration of your treatment. They may also decide to carry out a new simulation during the treatment, in which case, they will explain their reasons for doing this.



You do not have to have an empty stomach. Your position on the treatment table will be the same as on the simulator table, generally on your back, but sometimes on your stomach or side. The part of the body to be irradiated is stripped. Certain areas within the radiation beam and not requiring treatment will be protected. On some devices, these areas are protected by metal plates positioned on a platform between machine and patient (and therefore not on the body).
You must remain still throughout the irradiation process, to prevent the rays from attacking parts of the body that do not require treatment. All you should do is keep breathing calmly. During the irradiation process, the beam is pointed directly at the diseased part. The machines revolve and make noise. Even though you remain alone in the treatment room, you remain in communication via microphone with the carers, who watch you through two video cameras. The irradiation process lasts a few minutes for each irradiation field, totalling about 15 minutes per day. You do not become radioactive yourself after the irradiation sessions.
During your treatment, you may make an appointment with a radiotherapist-oncologist at any time. This will give you a chance to ask questions. The treatment is sometimes adapted according to changes in your personal situation. A machine different to the one with which you started the treatment may be used.
The radiotherapist-oncologist will determine which examinations and medicines may be necessary during the treatment.


You may have to wait your turn for an irradiation session or consultation. We do everything we can to limit waiting times. Delays are usually caused by adjustments to machines, emergencies, difficulties encountered in positioning another patient, or requests from other doctors for information on their patients. Your care team will do all it can to explain the reasons for the wait. Please do not hesitate to ask for an explanation, especially if you do not understand the appointment system.



Other treatments may be offered to you after irradiation. The radiotherapist-oncologist, in agreement with the referring doctor and the other specialists, will examine you regularly in order to assess your situation.
Secondary effects will reduce progressively over the weeks after the treatment finishes. A feeling of tiredness is normal, and will disappear slowly.



Strictly, you do not need to stay in hospital while receiving irradiation treatment. A stay in hospital may be envisaged if you have to be treated far from home, if your treatment is combined with chemotherapy, or if your situation requires it. We will discuss with you the means of transport best suited to your situation.
If you use your own vehicle, your own mutual insurance company will help you. Otherwise, you may be transported, each day or on several occasions per week, by taxi or ambulance. The choice of transport will depend on your state of health. If you have questions on this subject, please contact the social affairs department.



Like all treatments, radiotherapy can sometimes produce side effects. They vary significantly from one patient to another and depend on the dose of radiation given, the body part treated and each patient’s individual reaction. Numerous patients feel few or no side effects. Of course, treatment of these side effects will be adapted according to your problems and difficulties.
The doctor will inform you of the reactions that may affect you, and will offer you the treatment best suited to your state of health. You must report any reactions to the care team and the doctor.


Common reactions


Tiredness Regular rest, short walks and light exercise. Calorie and protein supplements, vitamins and trace elements.
Headache Medicine prescribed by the radiotherapist-oncologist.
Diarrhoea Medicine prescribed by the radiotherapist-oncologist and a diet low in residues.
Loss of appetite Eat more frequently and in smaller quantities. Consult a dietician if you wish
Anxiety and depression Talk about it. Your condition will improve if you obtain the help of a psychologist, make contact with other patients and friends and use the appropriate medicines.
Skin irritation, itching Never use any product without discussing it with your doctor. The radiotherapist-oncologist may prescribe you pomades and suitable localised care.
Hair loss Irradiation of a haired area can lead to loss of phaneras (scalp, beard, pubic hair, armpits etc). The hair will usually grow back in 2-3 months, depending on the dose of radiation received. Some types of chemotherapy can also trigger hair loss.
Inflammation of mucous membranes (nose, mouth, larynx, oesophagus, stomach, intestines, rectum, anus etc) The radiotherapist-oncologist can prescribe suitable medicines.
Cystitis (inflammation of the bladder) Drink plenty. The radiotherapist-oncologist can prescribe suitable medicines.





Why is there a long wait before my treatment begins?

In some cases (following surgery), the start of treatment should be delayed to allow a healthy scar to form.


Should I stop work?

The law states that you are entitled to full work incapacity benefit. Effects of radiotherapy can vary significantly from one person to another. Some people manage better if they can carry on working, either fully or in part. Your employer can also adapt your working hours.


Can I interrupt my treatment?

This is not advisable and should only be done with the consent of your doctor.


Why do I feel tired?

Tiredness may be linked not only to irradiation, but also to stress, disturbed sleep patterns and depression. The advice given to you will vary depending on the cause. If you have disturbed sleep patterns, avoid taking naps; if you are depressed, do not sleep longer than is normal. Generally speaking, it is better to maintain some level of physical activity than to rest more than usual.
During irradiation, your body consumes a great deal of energy. The feeling of tiredness or weakness reduces slowly after the treatment stops. To minimise tiredness after treatment, it is best not to work too hard. Try to sleep longer, and if possible, take short afternoon naps.


How can I avoid nausea?

Your doctor can prescribe you a suitable medicine. A light meal before irradiation can sometimes bring relief.


Should I follow a diet or avoid certain foods?

Your diet must be varied and balanced. In some circumstances, you may be asked to alter your eating habits. It is best to eat slowly and avoid fatty foods, spicy, acidic or very hot food, or food containing alcohol. It is best to eat small quantities. The radiotherapist-oncologist and a dietician will be able to advise you.


What if I lose my appetite?

To resist disease, your body requires a surplus of calories. Even a minimum of physical activity can stimulate your appetite. Eat as you feel inclined, and little and often. Where necessary, consult your doctor or a dietician.


Should I continue by blood pressure, cholesterol and diabetes treatment?

During the first consultation with the radiotherapist-oncologist, you must advise him what medicines you are taking. He will then decide whether your treatment needs to be changed. Normally, there is no need to interrupt the treatment that your GP or specialist has set up. If there is a problem, the radiotherapist-oncologist and your treating physician will discuss a suitable solution.


How should I dress?

Normally. Clothing that is too tight, or made of synthetic material, may irritate the skin. We recommend that you wear loose cotton clothing. Remember that during the treatment, the dye used to mark out the treatment area on your skin may stain your clothes.


Are there specific skin care treatments?

This depends on the part of the body treated, and specific creams or pomades may be prescribed. Normally, we recommend the use of mild, detergent-free cosmetic products.


Does the treatment alter sexual behaviour?

A number of patients experience changes in sexual desire and sexual relations during the treatment. In case of difficulty, do not hesitate to talk about this with people who can help you. For women whose pelvic area is irradiated, we usually recommend avoiding of sexual relations during and immediately after treatment. Irritation of mucous membranes can make sexual relations painful.


Can radiotherapy make you sterile?

Pelvic irradiation can cause temporary or permanent sterility. Women should generally wait until periods stop and other signs of menopause appear. Specific types of treatment may be offered. In men, irradiation of the sexual organs can reduce sperm cell production and fertility. If you want to have children but fear that the treatment could make you sterile, you can store frozen sperm before starting the treatment. For women, frozen eggs may also be stored.


I am also undergoing chemotherapy. Why?

Radiotherapy is just one form of localised treatment, acting only on an irradiated area. Chemotherapy acts on the whole body to prevent the spread of malignant cells. If chemotherapy is prescribed, it may begin before, during or after the radiation treatment. If it starts together with the radiation treatment, the dose of each treatment may be adapted as necessary.


Why have I been called back a few weeks after the end of my treatment?

Medical observation does not stop with irradiation. We assess the results and possible reactions to the treatment, and provide additional types of treatment where necessary. Specific examinations (X-rays, blood tests etc) may be necessary. The checks are conducted with the assistance of other doctors monitoring your condition.


Can I go on holiday?

Yes, provided radiotherapy is finished. Your GP or the radiotherapist-oncologist will give you a set of precautions to follow. If necessary, they may contact a doctor resident in the area in which you are on holiday. If you plan to visit a hot country, you must not expose the irradiated region to the sun, especially in the first year after irradiation. If you are travelling abroad, we recommend that you obtain advice on levels of cover provided by your insurance company, mutual fund etc


This file is based on a brochure by the SFRO (French Radiotherapy and Oncology Society).
The ABRO (Belgian Radiotherapy and Oncology Association) thanks the SFRO for allowing it to use this information.


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