Radiotherapy for children

Radiotherapy is a treatment that uses high-energy X-rays to kill cancer cells.

What is radiotherapy?

Radiotherapy is a painless treatment using high-energy X-rays that go deep inside the body to kill cancer cells.  It may be given:

  • To cure  

    Some treatment protocols may include a course of radiotherapy to shrink a tumour before surgery or to kill any cancer cells that remain after surgery to stop cancer spreading and cure the disease. 
  • To irradiate the whole body (total body irradiation) 

    This form of radiotherapy is often given to children who are having a bone marrow transplant. 
  •  To relieve symptoms (palliative) 

    Radiotherapy may also be given to relieve symptoms of the disease. Often a short course, sometimes only a single treatment, is needed.

Radiotherapy must be carefully planned so that the highest dose is given to the tumour area and as little as possible to the nearby cells. As part of the preparation, your child will have a planning CT scan.  

For younger children, the play specialist can prepare your child in advance.

Having radiotherapy

Your child will have their radiotherapy at St Luke’s Hospital or St James’s Hospital in Dublin. 

Having radiotherapy is a bit like having an X-ray. They will lie on a treatment table and the radiotherapy machine will move around them. It doesn’t hurt, but your child might feel nervous or scared while having treatment. 

You will not be able to stay in the room with your child during radiotherapy treatment, but you will be able to see your child through a glass window or on a monitor at all times.

The radiotherapy staff are used to dealing with children and can offer great help and support. 

Young children 

Young children, usually under 3 years of age, will have radiotherapy under a light general anaesthetic.

Older children 

Older children may take some time to get used to the size and noise of the machines. But this should get easier once they get to know the staff and their surroundings. 

How much radiotherapy will my child need?

Everyone’s treatment is different and individually planned. 

The dose of radiation your child needs will be decided and divided up into a number of treatment sessions. Treatment could last up to 6 weeks. 

Radiotherapy is usually given as one session each day for 5 days, with a rest at the weekend. 

What are the side-effects of radiotherapy?

Any side-effects tend to affect the area being treated. How severe these side-effects are will vary from person to person, depending on the amount of treatment received. 

Most side-effects develop during or shortly after treatment and get better within a few weeks. Late side-effects may develop some time after treatment. Some side-effects are long-term or may even be permanent. They may include:

  • Fatigue (extreme tiredness): Your child may feel very tired during treatment and for a few weeks afterwards. It may take a few months until your child’s energy levels get back to normal.
  • Nausea and vomiting: Radiotherapy to the brain or the tummy area can cause nausea and vomiting. It can also  sometimes lead to loss of appetite and weight loss. Your child's doctor and dietitian can advise and help with this.
  • Skin reaction in the treated area: The skin the treated area may become red and sore or itchy. The radiotherapy staff will give advice about skin care.

Read more about coping with side-effects.

Proton beam therapy

This is a type of radiotherapy that uses protons instead of X-rays to treat tumours. It does not improve the chance of cure, but it might reduce the risk of long-term side-effects.

It is not available in Ireland, but the HSE funds proton therapy in Essen in Germany for patients that are most likely to benefit from this option. Ask the medical social worker about charities and groups who may be able to support your family if your child is having this type of treatment.

Guide for families of children receiving proton beam therapy
Guide for families of children receiving proton beam therapy
Booklet 13 pages 7.24 MB
This leaflet will tell you all you need to know if your child is going to have proton beam therapy abroad. Available to download only.

Coping with radiotherapy

Usually children have radiotherapy every week day with a break at the weekend. 

For most children there is no need to stay in hospital when they’re having radiotherapy. This means you may need to travel to the hospital every day or stay overnight in Dublin if you live too far away. This can be tiring and or expensive. 

If you are travelling to the hospital from your home every day or paying for accommodation, ask the medical social worker about applying for the Travel2Care grant and our Children’s Fund.

Travel2Care is a fund made available by the National Cancer Control Programme (NCCP) and managed by the Irish Cancer Society. It is for patients who are having difficulty getting to and from their treatments while attending one of the national centres of excellence. Patients can apply if they are travelling over 50km one way to a national designated cancer centre or approved satellite centre.

The Irish Cancer Society’s Children’s Fund offers financial support to the parents of children diagnosed with cancer. This is to help them with the unexpected expenses that a diagnosis brings, such as travel expenses to cancer treatment appointments, heating bills, childcare costs and home help. This is a one-off grant of €3,000. It is not means tested. 

To qualify for the Children’s Fund, the child: 

  • Must be under the age of 18
  • Must have been diagnosed with cancer and is currently receiving treatment
  • Must live permanently in Ireland

For more information on these and other services available, call our Support Line on 1800 200 700.


We're here to help

Our range of free services is here for you.

Children's Fund
We provide a grant of €3,000 for families of children under 18 diagnosed with cancer, supporting families with the cost of a cancer diagnosis.
Julie Wren Complementary therapies
The Irish Cancer Society funds a haven on St John’s Ward in Children’s Health Ireland (CHI) at Crumlin, which provides massage, reflexology, mindfulness and meditation to children.
CAYA counselling and psychological support services
Free counselling for families affected by childhood cancer.

Talk to a Cancer Nurse

Support Line

Support Line

Our Cancer Nurses offer confidential advice, support and information for anyone affected by cancer. Call or email supportline@irishcancer.ie. Video calls available. Mon-Fri: 9am-5pm
Support Line

In-hospital support

The Irish Cancer Society's Children’s Cancer Nurse at Children’s Health Ireland at Crumlin Hospital one day per week provides free, confidential advice, support and information to anyone affected by a child’s cancer.
In-hospital support