Radiation therapy is a way of treating cancers using X-rays or other types of radiation. It is also known as radiotherapy.
The two main types of radiation therapy are external beam radiation therapy (EBRT) and brachytherapy.
What you need to know
Radiation therapy for bowel cancer
Radiation therapy is used to treat some bowel cancers. It can be given:
- before surgery to help shrink the cancer so it is easier to remove
- after surgery to kill any remaining cancer cells
- during surgery, called intraoperative radiotherapy
- with chemotherapy if surgery is not possible
- in advanced cancers to help relieve symptoms.
Not everyone who has surgery will have radiation therapy. Your doctors will tell you whether they recommend radiation therapy for you.
Most radiation therapy for bowel cancer is external beam radiation therapy (EBRT), although brachytherapy can also be used.
External beam radiation therapy (EBRT)
External beam radiation therapy (EBRT) uses beams of X-rays or other radiation to treat cancer from outside the body. The beams are produced by a large machine called a linear accelerator.
There are several different types of EBRT. Most involve having treatment 5 days a week for a number of weeks. Others only need a small number of treatments.
Before starting radiation therapy you will go to a simulation or planning session to work out how you will be positioned for treatment.
When you go for each treatment, most of the time is used to set you up in the right position. The actual radiation beam is only on for a few minutes.
EBRT is not painful and you won’t feel anything during the treatment. You will hear some buzzing noises and the machine will move around you but it won’t touch you. The radiation therapist can see and hear you throughout the treatment.
Brachytherapy treats cancers by using small radiation sources inside the body, or on or near the skin. Each source is slightly smaller than a grain of rice. When brachytherapy is used inside the body, it is sometimes called internal radiation therapy.
For some patients, the radiation source is put in place for a short time and then removed. For others, the radiation sources are put in the body and left there permanently. These patients can go home once the sources are in position.
The radiation oncology team
Health professionals who work as part of the radiation oncology team include:
- radiation oncologist
- radiation therapist
- radiation oncology nurse
- medical physicist.
What to ask or talk about
Side effects of radiation therapy for bowel cancer
Most people get some side effects when having radiation therapy for bowel cancer.
These can include:
- bowel problems - possible diarrhoea, incontinence or blockage
- redness and other skin changes
- hair loss in the treatment area
- bladder problems
- tiredness (fatigue)
- nausea and vomiting
- fertility and sexual problems.
Will I be radioactive?
External beam radiation therapy (EBRT) does not make patients radioactive.
Brachytherapy patients can be radioactive while they are receiving treatment. Those who go home with radioactive sources in their body will give out a very small amount of radiation which reduces over time.
Some other types of radiation therapy can also make patients radioactive for a time after treatment.
Preparing for radiation therapy
Before radiation therapy, you will need to sign a consent form. It is important you understand what you are consenting to and the possible side effects.
Some things you should know are:
- whether you need any tests before starting radiation therapy
- if you need to change your diet or medications
- when you have to be there
- if you need to have time off work
- if you will be able to drive after radiation therapy.