What is radiation treatment?
Radiation treatment is the use of high-energy radiation to destroy cancer cells or prevent them from reproducing.
Radiation treatment only affects the part of the body at which the beam(s) is aimed, so is very localised.
About half of all people with cancer need radiation treatment at some point in their illness. For some types of cancer this is the main treatment. It might also be used in combination with surgery, chemotherapy or hormone therapy.
Types of radiation treatment
Radiation treatment can be given in two ways: from outside the body or inside the body.
External beam radiation treatment is the most common method. This is where a radiation beam is focused from a machine outside the body onto the area affected by the cancer.
With internal radiation treatment (brachytherapy), radioactive material is put into your body, on or near the cancer. In some cases, a combination of both forms of radiation treatment is used.
Why is radiation used to treat cancer?
- To cure cancers, often in addition to other cancer treatment.
- To shrink a tumour so that surgery is more effective (neoadjuvant radiation treatment).
- To treat any cancer cells remaining after surgery (adjuvant radiation treatment).
- To control cancers – to keep cancer at bay for a long time.
- To relieve symptoms; for example, to reduce pain or a cough. This is called palliative treatment.
How does radiation treatment work?
Radiation treatment attacks cancer cells that are dividing. It also affects dividing cells of normal tissue. The damage to normal cells is what causes side effects. For each patient receiving radiation a decision has to be made about how much treatment to give while limiting damage to normal tissue. Different tissues have different tolerance levels to radiation.