Radiation therapy (also called radiotherapy) uses radiation, such as x-ray beams, to kill or damage cancer cells. The radiation is targeted at the treatment site to reduce the risk of damage to healthy cells. The treatment itself is painless, though you may experience side effects afterwards.
|Radiation therapy is usually combined with chemotherapy for the treatment of glioblastomas (grade 4 tumours). Compared with radiation therapy alone, this combination leads to better outcomes.|
Learn more about:
- How treatment is planned
- Stereotactic radiosurgery
- Stereotactic radiation therapy (SRT)
- Proton therapy
- Wearing a face mask
- Side effects of radiation therapy
- Video: What is radiation therapy?
How treatment is planned
Before radiation therapy begins, you will go to a planning or simulation appointment to plan the treatment. A radiation therapist will take measurements of your body and do a CT or MRI scan to work out the precise area to be treated. If you are having radiation therapy for a spinal cord tumour, some small tattoos may be marked on your skin to indicate the treatment area. If you are having radiation therapy for a brain tumour, you will probably need to use a face mask or head frame.
Radiation therapy is usually given once daily, from Monday to Friday, for several weeks. However, how often you have the treatment will depend on the size and type of tumour.
Stereotactic radiosurgery (SRS) is a special type of radiation therapy, not a type of surgery, so no cuts are made in the skull. It is used to treat some small brain tumours. A high dose of radiation is targeted precisely at the tumour, with very little reaching surrounding areas of healthy brain tissue.
Radiosurgery may be offered when neurosurgery is not possible or as an alternative to neurosurgery. It is most commonly used for metastatic cancers that have spread to the brain from another part of the body. It is also used for some meningiomas, pituitary tumours, and schwannomas, and is occasionally used for gliomas that have come back after other treatment.
Often, only 1−3 doses of SRS are needed. A treatment session may last between 15 minutes and two hours, depending on the type of radiosurgery given, and you will need to wear a face mask during the treatment. You will usually be able to return home afterwards.
Stereotactic radiation therapy (SRT)
A stereotactic radiosurgery machine may also be used to deliver a longer course of radiation, particularly for benign brain tumours. This is called stereotactic radiation therapy. The same precise system is used, but multiple small daily treatments are given.
Also known as proton beam therapy, this uses radiation from protons rather than x-rays. Protons are tiny parts of atoms with a positive charge that release most of their radiation within the cancer. This can be important near sensitive areas, such as the brain stem or spinal cord. Special machines, known as cyclotrons and synchrotrons, are used to generate and deliver the protons.
Proton therapy is not yet available in Australia. In specific circumstances, financial assistance may be available from the Australian Government to travel overseas for proton therapy.
Wearing a face mask
For radiation therapy to the brain, a plastic face mask may be made during the planning sessions. This is known as an immobilisation mask. It will help keep your head still and ensure the radiation is targeted at the same area during each session.
The mask is made of a tight-fitting mesh, but you will wear it for only about 10 minutes at a time. You can see and breathe through the mask, but it may feel strange and claustrophobic at first. The radiation therapist can suggest ways to help you adjust to the mask, so let them know if it is making you feel anxious or uncomfortable.
During treatment, you will lie on a table under a machine called a linear accelerator. Radiation therapy itself is painless.
Side effects of radiation therapy
Radiation therapy side effects generally occur in the treatment area and are usually temporary, but some may be permanent or last for a few months or years. The side effects vary depending on whether the tumour is in the brain or spinal cord. They may include:
- nausea – often occurs during the course of treatment
- headaches – often occur during the course of treatment
- tiredness or fatigue – worse at the end of treatment, can continue to build after treatment, but usually fades over time
- red, sore, inflamed or flaky skin – may occur in the treatment area, usually happens at the end of treatment and often worsens before improving
- hair loss – may occur in the brain tumour treatment area and may be permanent
- dulled hearing – may occur if fluid builds up in the middle ear
- swallowing problems (dysphagia) – may occur following treatment for spinal cord tumours
- diarrhoea – may occur after treatment for spinal cord tumours.
A small number of adults who have had radiation therapy to the brain have side effects that appear months or years later. These are called late effects and can include symptoms such as poor memory, confusion, personality changes and headaches. Rehabilitation therapies or medicines can help with managing late effects. Young children are more likely to have long-term effects from radiation therapy because their nervous system is still developing, so other treatments are used where possible.
Radiation therapy that affects the pituitary gland can lead to it producing too much or too little of particular hormones. If this is a risk for you, your treatment team will monitor the hormone levels in your pituitary gland. See Radiation therapy for more information.
Video: Radiation therapy
Learn more about what radiation therapy is, the types of radiation therapy, common side effects, and managing those side effects.