Radiotherapy for children

When your child is diagnosed with a brain tumour, they may be given radiotherapy as a treatment. This uses controlled and targeted doses of high energy beams of charged particles to destroy the tumour cells, whilst causing as little damage as possible to surrounding healthy cells.

Not all children diagnosed with a brain tumour will be able to receive radiotherapy as a treatment option.

Will my child have radiotherapy?

The decision to give radiotherapy will be based on a number of factors:

  • your child's age
  • location of their tumour
  • type and size of their tumour.
  • other factors e.g. whether the tumour is growing or causing symptoms.

If your child is under three years old, it is unlikely that they will be given radiotherapy. Radiotherapy can be damaging to very young children, having a long-term impact on cognition, growth and hormone levels.

However, some tumour types e.g. ependymoma, may be treated with radiotherapy in younger children, if the tumour is in the posterior fossa (the back of the skull).

How is radiotherapy given?


Your child's radiotherapy treatment is very carefully planned by a team of medical specialists to ensure that it reaches as many tumour cells as possible, whilst avoiding as much healthy tissue as possible.

Usually an additional CT scan, and sometimes an MRI scan, is needed to create a three-dimensional image of your child's brain and tumour to allow more precise planning of the treatment.

It is important that your child lies very still during treatment, so that the radiotherapy is directed to the correct part of the brain. A treatment mask is made specifically to fit your child's face and head. This mask fixes to the treatment couch to keep their head still each time they have treatment.

There are different types of masks, made from different materials. They are made by smoothing the warmed material onto your child's face, so that the final mask is an exact replication of the size and shape of their head. Gaps are left for the eyes, nose and mouth, so your child is always able to breathe easily.

Thermoplastic radiotherapy mask being made (there are other types of masks).

A play therapist may work with your child to make wearing the mask less daunting.

Images reproduced with the kind permission of Cambridge
University Hospitals NHS Foundation Trust.


Your child will lie on the treatment couch and staff will take some time positioning them. Before the radiotherapy machine is switched on, the staff will leave the room, but remain nearby. They will be able to see, hear and speak to your child, should they need them.

Your child won't be able to see or feel the radiotherapy beams nor feel any heat from it. They will be able to hear the machine.

If your child is very young or extremely anxious and won't keep still, a short general anaesthetic may be given.

How long will treatment take?

Treatment can take anywhere from a few seconds to a few minutes. Craniospinal radiotherapy can take a bit longer.

Your child's treatment is planned to suit their individual needs. A typical plan is daily treatments, Monday to Friday with a break at the weekends. Each treatment is called a 'fraction'.

Your child will have commonly have radiotherapy for around 4 to 6 weeks.

After treatment

If your child is having radiotherapy as an outpatient, they will be able to go home after each session. If they need to remain in hospital for another treatment, a nurse will take them back to their ward.

Your child will NOT be radioactive after treatment. It is safe for them to be around people, including other children.

After the whole course of treatment, your child will have regular check-ups to monitor the effects of the radiotherapy.

What are the side-effects of radiotherapy?

Short-term side-effects

  • Tiredness - this can continue for a number of weeks after treatment
  • Hair loss - this can be permanent, but see the Resources section below for help with this
  • Skin sensitivity - take extra care in the sun or strong winds or when swimming
  • Feeling nauseous- your child may be given anti-sickness tablets
  • Reduced appetite - giving them several smaller, healthy snacks may be better than three regular meals
  • Growth and development
  • Puberty
  • Intellectual development and cognitive impairment
  • Emotional difficulties

Long-term side effects

Unfortunately, because a child's central nervous system is still developing, radiotherapy can cause some long-term effects with:

  • Growth and development
  • Puberty
  • Intellectual development and cognitive impairment
  • Emotional difficulties

Your child's health team will talk through any side-effects with you before treatment, and can help you with any effects your child develops.

Page last reviewed: 02/2014
Next review due: currently under review

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