After radiotherapy for breast cancer

Radiotherapy to the breast can sometimes lead to long-term side effects, but most of these are rare.

How the breast looks and feels  Back to top

After radiotherapy, small blood vessels in the skin can be damaged causing red ‘spidery’ marks (telangiectasia). These affect how the breast looks but are harmless. Your skin may also have a slightly darker tone. It’s not unusual for the breast to feel firmer, and over months or years it may shrink slightly in size. If you’re unhappy with the shape of the breast or if it isn’t the same volume as your other breast, discuss this with your doctors. There are usually techniques, such as reducing the size of your other breast, that can be done to improve the appearance.

Other late effects Back to top

Rarely, a few months after radiotherapy some women develop breathlessness| due to the effect of radiotherapy on the lung. It usually gets better within 2–4 weeks without any treatment or it may be treated with a short course of steroids. Radiotherapy rarely causes any long-term damage to the lungs.

Women may worry about the effects of radiotherapy on the heart. Radiotherapy is now very carefully planned to avoid including the heart in the treatment area. It very rarely causes heart problems and only women who have cancer in their left breast are at risk. You can read more about how lifestyle changes can help you look after your heart 

Rarely, radiotherapy weakens the ribs in the treated area, making them more likely to fracture (break) than normal.

These side effects are uncommon. If you’re worried about the risk of developing particular side effects from radiotherapy, talk to your cancer specialist.

We have more information about the possible long-term side effects| of radiotherapy for breast cancer.