Radiotherapy is a method of using radiation to kill cancer cells.

Types of Radiation Used:

1. Alpha Emitters

• Alpha radiation is very strongly ionising, meaning it can do a lot of damage to the tumour cells it's placed near.
• Alpha particles have a short range, so they only affect nearby tissue, limiting damage to healthy cells around the tumour. Example: Injecting an alpha emitter near a tumour to kill cancer cells while sparing nearby healthy tissue.

2. Beta Emitters:

• Beta radiation is used in implants placed inside or next to the tumour.
• Beta particles can travel further than alpha particles, which means they can damage cancer cells beyond the immediate area of the implant.
• These emitters are useful because they can penetrate through the casing of the implant to reach and damage cancer cells, but they can also harm cells further away.

Gamma rays are used because they can penetrate deep into the body, reaching the tumour even if it is located in a hard-to-reach place.

• The radiation is carefully focused on the tumour to limit damage to healthy cells, but some harm to surrounding tissues is unavoidable.
• Shielding can be placed on other parts of the body to protect healthy areas from radiation exposure.