Radiation burn: radiotherapy skin reactions, care and recovery

Radiotherapy uses high-energy rays to treat cancer, and the beams pass through the skin on their way to the area being treated. Healthy skin cells in the treated area can be affected too. The result is a skin reaction that people often call a radiation burn. It is not a burn in the sense of a heat injury, but it can look and feel like sunburn.

The NHS lists skin soreness as one of the side effects of radiotherapy and explains that side effects vary from person to person and depend on factors such as the part of the body being treated and the type of radiotherapy. It adds that many side effects can be treated or prevented and most go away after treatment stops, and that in some cases side effects only develop months or even years after treatment starts.

The Gloucestershire Hospitals leaflet describes a skin reaction as something you may develop during radiotherapy and for a while afterwards, in the area being treated. It is local: it affects the skin in the treated area rather than the whole body.

Most people have some degree of skin change. Many have only mild changes that are managed with moisturiser and gentle care, while a smaller number have more troublesome blistering or peeling that needs dressings and pain relief.

The Gloucestershire leaflet describes the skin in the treated area gradually becoming pinker or darker, depending on skin tone, feeling dry or tight and sore, or developing a rash and itching. The NHS describes the skin becoming sore, changing colour (red, lighter or darker than your usual skin tone), or dry and itchy, and sometimes blistering and peeling.

Both sources describe the colour change in relation to your usual skin tone, so it may look darker or lighter rather than red. Soreness, tightness and itching are also part of the picture.

• Pinker, redder or darker skin in the treated area.

• Dryness, tightness or soreness.

• Itching or a rash.

• In more severe reactions, blisters or peeling skin, especially in skin folds.

• Skin that is slightly darker or lighter than before once it has healed.

The sources give slightly different timings, which reflects the fact that reactions vary. The NHS says changes tend to start 1 to 2 weeks after treatment begins. The Gloucestershire leaflet says a reaction usually begins about 10 days after starting treatment, may appear at any time and continues after radiotherapy is completed.

The skin may get worse before it gets better. The leaflet says your skin reaction may worsen for 7 to 14 days after finishing radiotherapy, then gradually improve, and that most patients find their skin has healed by about a month after treatment finishes, although if the skin has broken, healing may take longer. The NHS says skin problems usually settle within 2 to 4 weeks of treatment finishing, though sometimes your skin might stay slightly darker or lighter than before.

The Gloucestershire leaflet lists several things that can make a skin reaction worse. Having treatment to areas with skin folds, such as the groin, breast, anal or rectal area or armpit, can worsen it because these areas can be warm, moist and rub together, and the skin may develop blisters or peel. Treatment to the head and neck can result in a more severe reaction because the skin in this area receives a higher dose due to the position of the tumour.

Systemic anti-cancer treatments such as chemotherapy given alongside radiotherapy can increase the sensitivity of the treated area. Smoking will make a skin reaction worse, and a reaction is also more likely if you are overweight or have other conditions such as heart disease or diabetes. The leaflet advises asking your treatment team for help to stop smoking.

The NHS and the Gloucestershire leaflet give broadly similar skin care advice, and your own radiotherapy team may give you more specific instructions that take priority. The advice applies to the skin in the treated area.

The NHS advises telling your care team if you notice any soreness or changes to your skin, and to stop using any products on your skin if it breaks. The Gloucestershire leaflet explains that if the skin blisters or peels, the team will be able to help with dressings and pain relief.

Contact your radiotherapy team or review radiographer straight away if the skin becomes very sore, breaks open, weeps, smells or looks infected. The Gloucestershire leaflet notes that you can contact the team after the end of radiotherapy for advice by telephone or in a face-to-face appointment, and that contact details are given at the end of the course.

Always ask your team before applying creams or dressings that were not recommended to you, because some products can irritate the skin or affect treatment.

Treated skin stays more sensitive to the sun for a long time. The NHS recommends continuing sunscreen for at least a year after treatment ends, and the leaflet advises being careful in the sun for at least a year after finishing.

Treated skin may stay slightly darker or lighter, as the NHS notes. The NHS also says that radiotherapy side effects can occasionally appear months or years after treatment, so tell your GP or cancer team about any new skin changes in a previously treated area.

Radiotherapy in the NHS is delivered through hospital cancer centres. Skin care advice may vary between centres, so keep to the instructions you were given at your own centre.