What is Radiation Therapy?
Cancer is a generic name given to a group of diseases that involve uncontrolled multiplication of abnormal cells. The cells grow in size, affecting the original and adjacent organs and tissues. Radiation therapy uses radiation to kill or damage these abnormal cells and stop them from growing and multiplying.
Cancerous cells are more susceptible to radiation than healthy, non-cancerous cells because of their abnormal and unstable nature. Healthy, non-cancerous cells are much better at recovering from exposure to radiation and will normally repair themselves, but the cancerous cells cannot recover.
To use the difference between normal and cancerous cells most effectively, radiation therapy is usually delivered in daily intervals called ‘fractions’. This allows time between treatments for the healthy cells to repair and the cancer cells to die off.
Radiation therapy requires a complicated planning process because Radiation Oncologists will optimise the radiation dose to treat the cancer, while minimising (and where possible avoiding) dose to healthy organs and tissues surrounding the cancer.
How is radiation therapy delivered?
There are two main types of radiation therapy: External Beam Radiation Therapy (EBRT) and Brachytherapy:
- EBRT - During external beam radiotherapy, the radiation oncology team uses a machine called a linear accelerator (Linac) to direct high-energy X-rays at the cancer.
- Brachytherapy - Otherwise known as Internal radiotherapy, this involves placing radioactive sources (radioactive seeds) inside the bod