Chloes Chemoo Cows


What is radiotherapy?


Radiotherapy is used to treat conditions such as cancer, thyroid disorders and some blood disorders.


The word 'Radiotherapy' comes from two words:


Radio 'radiation’


Therapy 'treatment'


Radiotherapy treats cancer by using high-energy rays which destroy the abnormal cells, whilst doing as little harm as possible to normal cells.


Radiotherapy can be a frightening experience for both children and their parents, but once everyone understands what is involved this fear can be reduced. The radiotherapy staff are used to treating children and they can offer help and support.


Although you won't be able to stay in the radiotherapy room during your child's treatment, you can watch through the window or on the TV screen.


Only some children will receive this type of treatment as its use depends upon the type of cancer they have and where it is in the body. When treating brain tumours for example, radiotherapy is now avoided, if at all possible, for children under three to help minimise any long-term side effects.


How does radiotherapy work?


All human cells contain DNA, the instruction code which tells the cell what it is and what it is to do. Radiotherapy (or the radiation it contains) destroys this DNA within the cancer cell. This causes the cell to die and shrinks the size of the tumour.


Radiotherapy is often given with the aim of destroying a tumour and curing the cancer. Radiotherapy given in this way is described as curative or radical radiotherapy.


Radiotherapy may be used on its own or may be given before or after surgery or chemotherapy. Chemotherapy is the use of anti-cancer drugs to destroy cancer cells. If radiotherapy and chemotherapy are given at the same time, this treatment is known as chemoradiation.


For some types of curative radiotherapy treatment, you may need to go to the hospital each weekday for between two and seven weeks. In this situation, a small dose of radiotherapy is given each time. This is because as well as damaging cancer cells, radiotherapy can also cause damage to healthy cells in the treatment area. If a very high dose of treatment is given in one go it can cause too much damage to the healthy cells, so small doses are given to allow them to recover in between.


The treatment is not painful and lasts a few minutes. The procedure is a bit like having an X-ray taken and the child has to lie very still.


The length of treatment will vary from child to child. The treatment is planned carefully and may involve a scan or X-ray to accurately pinpoint which areas is to be treated.


A mark is drawn on the child's skin so that the treatment is given to the same spot each time.


Staying still


It is vital that the child stays still during treatment. Because of this, the doctor may give a very young child a sedative or even general anaesthetic to help them relax or sleep.


The nurses will look after the child until they wake up, usually after 20 minutes to an hour. You will then both be able to go home, unless your child is an inpatient, in which case a nurse will take them back to the ward.


Older children may take a while to get used to the size and sound of the machines, but this should get easier once they get to know the staff and the surroundings.


Mask or Shells


A clear plastic mould will be made to immobilise the area that is to be treated. These devices, also known as masks or shells have to be made for each individual child to use during treatment. The child lies on the treatment table and the mask or shell fixes over them and onto the treatment table. This stops them moving.




There are always side effects. Some of the side effects happen immediately, some after treatment and some take longer to show.



Some children develop a skin reaction to the radiotherapy after a few weeks. The area of skin that is exposed to the radiotherapy can become sore, red and itchy. The radiotherapist will be looking for signs of this reaction, which can look like sunburn.


Sights, sounds and smells

Radiotherapy to the brain can cause unique and strange side effects. Occasionally patients report seeing, hearing or smelling strange things.


Radiotherapy can sometimes cause some long-term side effects. These do not happen to every child and vary in how severe they are.



Radiotherapy to the brain often results in swelling, usually at its greatest about ten days into treatment. If swelling causes problems small doses of steroids are used to reduce symptoms.


Hair Loss

Radiotherapy to the brain usually results in hair loss in the area being treated. It starts to fall out after about two weeks of treatment and is usually gone by the end. It usually starts to grow back about three months after treatment, however sometimes hair can grow back thin and patchy or not grow back at all. This is usually the case in areas that receive high doses of radiation.



A long course of radiotherapy makes patients tired. This is at its worst near the end of the treatment and just afterwards.


Long-term side effects

Most children will not have any problems as a result of their illness. But there are some long-term problems associated with cancer treatment. These vary depending upon the type of cancer and treatment the child has had.


Attendance at a follow-up clinic will help identify and manage any long-term side effects. Not all children treated in the same way will have the same long-term side effects. It is difficult to accurately predict who will be affected and today's new treatment regimes aim to reduce the incidence of such side effects.


Below is a list of potential long-term side effects that are known to be caused by certain cancer treatments. Parents can ask their child’s Consultant about these in more detail.



Radiotherapy to the brain, abdomen or pelvis (including the testicles or ovaries) can affect puberty. Certain chemotherapy drugs and operations can also do this.


In some children the start of puberty may be delayed because of changes to the way their body produces hormones.


The child will be monitored at the follow-up clinic for signs of puberty. If it is delayed hormone therapy can be given so that it occurs.



Cancer treatment can affect a child's ability to have children of their own in the future. This is hard to determine until puberty. If the child being treated has already reached puberty they will have hormone tests to see if there is a problem.


Boys who have gone through puberty can be given the option of banking their sperm before treatment.


Growth and development

Radiotherapy can have effects on growth and development. There are two main ways that this can happen.


Growth hormone is produced by the pituitary gland in the brain. If a child was given radiotherapy to the brain, the production of growth hormone may be affected.


The child may therefore not grow properly and may need artificial growth hormone.


Radiotherapy may also affect the growth of bones treated by radiotherapy. This may lead to one leg or arm being shorter than the other. A Consultant can give a better idea of what to expect in this situation.


Intellectual development

The majority of children returning to school after treatment experience no long-term problems. An exception is children who have been treated for a brain tumour. Their treatment means they are more likely to have 'developed' learning difficulties, which call for special help at school.


It has been suggested that up to 50% of children treated for brain tumours will need some sort of special support when returning to school. Today, if possible, many children under the age of three do not receive radiotherapy if they have a brain tumour. This is because their brains are rapidly developing and are therefore more vulnerable to long term side effects. Medical professionals are keen to avoid these side effects as much as possible.


Heart and lungs

Both chemotherapy and radiotherapy can alter the way the heart and lungs work. This can continue for some time after treatment and is monitored at the follow-up clinic.


Kidney function

Certain types of chemotherapy drugs can affect the kidneys, but this is not usually severe.


Secondary cancer

It is possible, although rare, for a child to develop a different cancer later in life because of their initial treatment. The risk of this happening is very low but is more likely with certain types of treatment. Parents can talk to their child's Consultant for further information.




Clic Sargent


Chloes Chemoo Cows