In medicine, high energy waves known as radiation are used to diagnose and treat various medical conditions.
X-rays use low levels of radiation to create images of the body. These images help your doctor diagnose your condition accurately.
Ionising radiation can also be used to treat cancer.This is known as radiotherapy. During radiotherapy, high-energy photons (X-rays or gamma rays) or particles (neutrons, protons and electrons) are used to destroy the DNA in cancer cells which helps stop the cancer from growing.
To understand how radiation works, it may help to know that normal cells grow and divide in a cycle. This happens in all cells and is happening all the time. The cell cycle is normally tightly controlled; however, this regulation may be lost in cells that are cancerous, leading to rapid cell division and uncontrolled growth.
Radiotherapy damages the cell’s DNA at the point during the cell cycle when the cell divides. Rapidly dividing cells are the most sensitive to radiation – so it destroys these cells first. This can hinder the cell cycle to prevent cell proliferation and tumour growth, however it can also affect the cells of normal tissues that are dividing at a slower rate. Radiotherapy is therefore commonly targeted only at cancer cells to reduce side effects.
Radiotherapy in early breast cancer
Radiotherapy in metastatic breast cancer
For example:
In breast cancer, radiotherapy is commonly given by a machine that emits beams of radiation directly at the area where the tumour is located (external beam radiation).
Various types of radiotherapy may be offered. These include whole breast radiotherapy or partial breast radiotherapy. Your doctor will talk to you about which method is most suited to your type of breast cancer.
The radiotherapy schedules for metastatic breast cancer are different from those you may have experienced already. If you need radiotherapy, you will have to visit the radiotherapy department at the hospital.
You might have one treatment a day for a few days or over a couple of weeks. Each treatment is called a fraction and takes a few minutes.
Radiotherapy can cause side effects. These may vary from person to person and will depend on the type of radiotherapy and target organs.
Talk to your doctor about the potential effects of radiotherapy and the best treatment options for you.
PP-UNP-IRL-0796. Date of preparation: July 2024