Two women having a conversation

What to expect from your breast cancer radiation therapy

Many patients with breast cancer will receive radiation therapy (or sometimes referred to as radiotherapy) at some point in their treatment course. It is often used to decrease the risk of your breast cancer recurring after surgery.  

Many patients with breast cancer who are receiving radiation therapy may have had prior therapies for their cancer e.g. a lumpectomy or mastectomy, chemotherapy, or endocrine (hormone-based) therapy. 

How does radiation therapy work?

Radiation therapy uses carefully controlled, high-energy particles such as X-rays or protons to destroy or damage cancer cells. The radiation is painless and invisible and you will not be radioactive after your treatment.  

By precisely targeting the breast and lymph nodes, the goal of radiation therapy is to stop the growth or spread of the breast cancer cells while minimising side effects and preserving surrounding healthy tissues. 

The radiation therapy is often delivered in ‘fractions’ which are daily intervals or doses. Delivering radiation doses in fractions allows time for the healthy cells that are exposed to the radiation to repair between treatments while allowing the cancer cells to die. 

What type of radiation therapy is used for breast cancer?

The most common type of radiation therapy for breast cancer is external beam radiation. This uses high-energy radiation beams delivered by a linear accelerator (or LINAC) machine to deliver radiation from outside your body to destroy cancer cells in the breast. Advanced techniques are used to deliver the radiation therapy at a precise dose to the targeted treatment area.

What happens before radiation therapy begins?

Before treatment starts, your radiation oncologist will review your health record, talk about your general health and diagnosis, and explain the treatment process, options, and potential side effects.  

Arrangements will also be made for a CT simulation appointment where the radiation therapists scan you. Your radiation therapist will help to position you for a CT scan. Your position will vary depending on the exact area of the breast you are having treated (e.g. with your arms above your head, on your chest or by your side).  

Marks may be drawn directly onto your skin to outline the treatment area using a special skin marker and, these will come off quite easily. Using images obtained from your CT scan, together with any additional scans, a personalised treatment plan will be devised to treat your cancer with radiation therapy. 

What happens at a first radiation therapy appointment?

You will be positioned on the treatment bed in the same position as your CT scan. The treatment machine delivers your radiation treatment from several different angles. The skin markings and individual treatment plan are used to deliver the prescribed treatment.

Radiation therapy is usually delivered in small daily doses called ‘fractions’ over five consecutive days in a 3–6week period. Each individual session takes about 10–20 minutes to complete. When the dose is being delivered, the radiation therapists will monitor you from another room, but you will always be able to communicate with the therapists through an intercom during your treatment and they can pause the treatment if required.

While you’re receiving treatment, listening to music can help you relax, and it is possible to bring your own music to listen to, or organise a playlist with your radiation therapist.

After a treatment session most people can continue to carry out their usual daily activities including work. However, if you are unable to carry on your normal activities, please discuss this with your treatment team. The nursing team are always available and will provide you with information on how best to manage any side effects that you may experience, such as skin changes around your breast and managing fatigue.

You will not be radioactive during or after external beam radiotherapy treatment. You can safely mix with other people, including children and pregnant women, at any time during and after your treatment.

What happens after I finish my radiation therapy treatment course?

Once your treatment course is completed, you will have a follow-up appointment with your radiation oncologist. This is often 1–3 months after completing your therapy, and you and your doctor will monitor your progress, assess any late side effects, and check to see how you responded to treatment. Your nurse will also follow-up with you to monitor and advise you on how to manage any side effects that you may experience.