Radiotherapy for breast cancer can cause side effects. These can happen during treatment, soon after, or much later after treatment has finished. Early (sometimes called acute) side effects happen during and soon after radiotherapy. Everyone is different so it is not possible to say exactly when side effects will start, end, or how severe they will be. The best advice is to talk to your team if you are concerned about anything at all.
You might have side effects or symptoms not listed here, because everyone and every treatment is different. They may also be caused by a different part of your cancer treatment. Research and support for side effects and late effects of radiotherapy is growing.
Joining a support group can be a positive way to share your experiences, feel less alone, and come to terms with the physical and emotional impact of treatment. Ask your treatment or clinical team if you need more support or have any side effects at all.
This page looks at early side effects.
How likely am I to get early side effects?
Before treatment you will discuss and sign a consent form with your clinical oncologist or therapeutic radiographer. They will tell you what your chances are of getting early or late side effects and you can ask any questions you might have.
You can read different radiotherapy consent forms (HERE) based on the specific area being treated. These consent forms are packed with useful information about early and late side effects.(1)
When you consent to treatment, you are saying you understand that you have a chance of getting early and late side effects. Your team will use words like Expected, Common, Less Common and Rare.
This table shows what these words mean.
| Wording on the consent form | % chance of side or late effect | How many patients will get this? |
|---|---|---|
| Expected | 50 to 100% | Between half and all patients |
| Common | 10 to 50% | Up to half of all patients |
| Less common | Less than 10% | Fewer than one in ten patients |
| Rare | Less than 1% | Fewer than one in 100 patients |
Early side effects (during or soon after treatment)
- Feeling very tired or fatigued: You might feel very tired during and after your treatment. It’s important to get plenty of rest but sometimes you will still feel really tired, even with lots of sleep. Some tiredness can be caused by having cancer and having cancer treatment, and some can be caused by travelling to and from hospital every day for treatment.
- Skin reactions: You might notice a change in colour, swelling, itching, or changes in the texture of your skin where you’re treated. For people with lighter skin tones these changes can be pink, red or darker than the surrounding area. People with brown and black skin tones might have colour changes such as maroon, purple, yellow or grey pigment changes. Or the skin can look darker than the surrounding area. These changes usually improve after treatment, but this can take 4 to 6 weeks in some cases.
- Hair loss: you might lose hair in the area where you are treated. For example, the armpit close to where you have treatment. Often, this grows back over time.
- Swelling: you might have some swelling where you are treated, known as Lymphoedema. It can last for several weeks or longer. Speak to your team if this happens to you.
- Breast changes: Sometimes the breast can feel heavy and warm to touch during treatment and the texture may change. This can be normal but can also indicate an infection so tell your treatment team of any changes.
- Sore throat: If the treatment is close to your throat it may cause soreness.
- Lung inflammation: This is rare but can lead to a cough or feeling out of breath.
- Pain in breast area: You might have some pain where you are treated, and around the scar area if you’ve had surgery. You might have nerve pain, tightness or tingling in the breast or down your arm that can cause problems with arm movement.
How to feel better during or soon after treatment
Here are some ideas you can try to make you feel better.
- Resting: Get lots of sleep and take breaks if you feel tired. You need to take this side effect seriously and listen to your body when you feel like this.
- Medication: if you have pain in and around where you are treated, your treatment or clinical team can prescribe medicine that helps manage this.
- Drinking fluids: Drinking plenty of fluids such as water, juice and squash can help with fatigue and tiredness caused by your treatment. It can also help flush out toxins in your body caused by treatment. You can try diluted juice if you don’t like water.
- Skin reactions: Your treatment team can suggest creams to calm your skin. Sometimes, extra care is needed if the skin breaks down in the treatment area. Talk to your team about washing, shaving and caring for your skin in your treatment area. You might have to change your normal routine during treatment and for a short time after, especially if you have a radiation skin reaction.
- Mobility exercises: Difficulties with arm movement after surgery is common. This can often be worse during and after radiotherapy treatment. There are exercises that can help with this, ask your team or find some good resources with examples at the bottom of this page. It can be helpful to do these exercises even before your treatment starts.
- Keeping active: Gentle movement can help you feel better, both during and after treatment. Your treatment team can tell you what is safe for you to do.
- Alcohol use: Please follow the NHS guidelines on safe drinking levels and any instructions you get from your team on what is right for you, your diagnosis and your treatment. If in doubt, please ask your team.
- Sexual changes: Talk to your team if you are experiencing issues with sex and cancer and they can offer advice.
- Stop smoking: If you are looking to stop or reduce smoking, there are services available to help you.
Click here to learn more about late effects.
Further information
Touch, Look, Check | Breast Cancer Now
Learn more about radiotherapy consent forms here:
https://www.rcr.ac.uk/our-services/management-service-delivery/national-radiotherapy-consent-forms/
Mobility exercises
