You have been given this leaflet because you have had surgery for breast cancer and have been recommended to have radiotherapy treatment to your chest wall and lymph nodes. This is called adjuvant treatment.

After a mastectomy there remains a risk of a cancer returning in the chest wall and lymph nodes. Research has shown that radiotherapy to the chest wall reduces the chance of the cancer returning. It also improves survival by a small amount. If chemotherapy is also recommended, the radiotherapy is usually given after the chemotherapy has been completed. The extent of surgery carried out in the armpit area varies with each person. When tests show that the cancer has spread to the lymph glands removed during surgery, there may be a need to treat the remaining lymph glands with radiotherapy. The aim of this treatment is to prevent the recurrence of the cancer in any of the lymph glands which remain.
During your radiotherapy treatment you will need to lie on a special piece of equipment called a breast board. This is used to help you remain still and be positioned in the same way each day for treatment. We will also need to mark your skin with small permanent tattoos. These are each the size of a full stop. These tattoos are used to place you in the correct position each time you have treatment.


Radiotherapy treatment is painless. However, it does have some side effects and you may notice one or more of them gradually developing over the course of treatment.
Please note that it is rare to experience all of these side effects.

You are likely to experience some skin changes in the area being treated. This can vary from mild darkening to quite marked peeling and blistering. For most people, the irritation is mild and can be effectively eased with the use of one of our recommended creams.

You may feel tired, especially toward the end of a course of treatment. Listen to your body and, if necessary, allow yourself extra time to rest. You can continue working if you feel able to. Gentle exercise and drinking more fluids can also help reduce the tiredness. It will wear off over a few weeks, once the treatment ends.

Some people experience discomfort or describe their chest wall and treatment area as feeling different. Occasionally it can become swollen during treatment. You may also experience sharp shooting pains and twinges, which can be related to the re-growth of nerves. If this happens, the pain is usually minimal and can be treated with mild painkillers if needed.

Nausea (feeling sick)
It is very rare to experience nausea during this treatment, but if it happens it is usually mild. You may wish to try eating and drinking small amounts, little and often.

Any side effects that you experience during treatment will continue to worsen up to approximately two weeks after treatment. They then usually slowly settle during the following few weeks. Please do not worry as this is quite normal. During this time, you should continue to follow the advice you have been given during your treatment. Continue to take any prescribed medication for the side effects until they settle down.


Long term side effects (‘late effects’) can occur months to years after radiotherapy. These side effects are hard to predict and, if they do occur, they can be permanent. In most people, these effects are mild and do not interfere with everyday activities. However, a small proportion of people develop more marked effects which can be troublesome. It is extremely rare for someone to develop several side effects. We plan the treatment to avoid the surrounding areas as much as possible, to reduce these side effects.

Your chest wall may become swollen, tender, and warmer to touch, several months after treatment. This is known as edema. If this happens, continue using moisturizing cream on your chest wall every day. Edema can be associated with pain, discomfort, short shooting pains and twinges. If your chest wall becomes swollen, please contact your oncologist or GP.

Long term, persistent pain in your chest wall area may occur. If you experience this, please speak to your GP, or consultant.

Shoulder movement
Some restriction in the range of your shoulder movement may occur on the side which has been treated. Some gentle exercises and using your arm normally, will help keep your shoulder more flexible. Take note, however, do not carry heavy loads or your handbag on that arm. Avoid injuries of any kind to the arm.

Swelling of your arm (lymphoedema) may occur. It is caused by scar tissue, which may form after an operation in the armpit or radiotherapy to the armpit. Lymphoedema can be managed with combinations of exercise and massage, as advised by your oncologist or physiotherapist.

Rare side effects

You may notice dilated capillaries (tiny blood vessels) under your skin in the area that has been treated. These marks are called telangiectasia. They can look unpleasant but do not cause problems.

Lung fibrosis
Radiotherapy can cause scarring (fibrosis) of a small area of lung tissue, which can (rarely) cause some degree of breathlessness. If this happens, please contact the center or go to the nearest emergency department to you for attention. Every effort is made to limit the amount of lung included in the treatment area, to minimize this risk.

Radiotherapy can make bones brittle and more likely to break. With chest radiotherapy, the bones at risk are your ribs. Rib fracture is very rare but is painful. A fracture usually heals without any treatment. You should speak to your doctor if you feel you have damaged a rib in some way or if your rib pain continues.

Radiotherapy to the chest wall may affect a small amount of heart tissue and make you more susceptible to heart disease. Breast cancer radiotherapy increases the risk of heart disease by less than 2%. If you experience any symptoms, please contact the center or go to your nearest Emergency department. Every effort is made to exclude the heart from the treatment area, to minimize this risk.

Second malignancy
Radiotherapy is associated with a small risk of developing a second cancer many years later, as a result of the radiotherapy. In non-smokers, this risk is usually less than 1%, which is much less than the risk of not treating the chest wall. If you are a long-term smoker, the risk is larger (around 2-5%), but you can greatly reduce this risk by stopping smoking.

Nerve damage
Damage to the nerves supplying your arm (brachial plexus neuropathy) is a rare and serious side-effect. It can cause pins and needles, numbness, pain and weakness (paralysis) in your arm and hand. If this happens, please contact the center to see your doctor.

If you have any questions during your radiotherapy, please speak to one of the RT therapists or your doctor when you come in for treatment.

Sebeccly Cancer Support: 0808 711 1629
Cancer Aware: 0810 557 5164
* Please note the NLCC is not affiliated with; and does not endorse any of the listed organizations.