Actinic keratoses are common lesions that develop on your skin as a result of cumulative life-long exposure to the sun. The lesions develop when your skin can’t repair the damage that has been caused by ultraviolet (UV) light. In the UK, about one in four people over 60 have actinic keratoses.
At first, you may notice small, rough spots on areas of your skin that are frequently exposed to sunlight, such as the skin on your face, ears, forearms and hands. These lesions can, however, develop anywhere on your body that is repeatedly exposed to the sun. The spots usually have no other symptoms but feel rough and are sometimes like sandpaper. They may also come and go without treatment.
Most actinic keratoses are about 5 to 10mm wide. Over time, the spots may get bigger (up to about 20mm) and usually become red and scaly. However, their appearance can differ hugely. For example, they may be skin coloured, pink or brown. Also, they can become raised, hardened and wart-like and may even develop a small horn-like growth. Equally, they can remain soft or flat. The skin surrounding the actinic keratoses often looks sun-damaged, for example, blotchy and wrinkled.
If you have any of these symptoms, see your GP.
Actinic keratoses are usually harmless but show that the skin cells have been significantly damaged (dysplasia). If the damage progresses, the cells can develop into a type of skin cancer called squamous cell carcinoma, but this is rare, happening to less than six in 100 people with actinic keratoses. If your actinic keratoses lesions become tender or form a nodule with crusting on your skin, see your GP as this can be an early sign of skin cancer.
Treatment can be effective if the cancerous changes in your skin are diagnosed early. See our skin cancer factsheet for more information.
Actinic keratoses are caused by repeated exposure to UV radiation from the sun. The more time you have spent in the sun throughout your life, the more likely you are to develop the condition. Because of this, people living in sunny countries, such as Australia, have a higher risk of developing actinic keratoses.
You may also be more at risk of developing actinic keratoses if you:
There are also certain genetic conditions, such as xeroderma pigmentosum (where your skin is unusually sensitive to the sun) or albinism (where you have no pigment in your skin, hair and eyes), which will also increase your risk of developing actinic keratoses. However, these types of conditions are very rare.
Your GP will ask about your symptoms and examine your skin. The appearance and distribution of the actinic keratoses on your body is usually enough to confirm a diagnosis.
If your lesions become tender, grow or bleed, you may be referred to a dermatologist (a doctor who specialises in identifying and treating skin conditions). He or she may take a sample of your skin (known as a biopsy) under a local anaesthetic, to check for skin cancer. This will be sent to a laboratory for testing.
Depending on the severity of your condition, your GP will be able to advise you about which treatment is most suitable. Sometimes, actinic keratoses can disappear on their own without treatment. If you have been diagnosed with actinic keratoses, you should always take extra care in the sun (see Prevention).
Your GP may prescribe one of the following topical medicines to treat actinic keratoses. A topical treatment is a medicine you apply directly to your skin.
These treatments can cause side-effects such as itching, redness and rashes. Always ask your GP for advice and read the patient information leaflet that comes with your medicine.
This involves freezing your actinic keratoses lesions with liquid nitrogen. Cryotherapy is less likely to leave a scar than surgery, but it can sometimes leave a pale mark. Cryotherapy can be quite uncomfortable, so it's usually used when there are only a few small actinic keratoses, or if you have the more scaly type of lesions that are known to respond less well to topical treatments.
This uses a cream to sensitise the actinic keratoses to light. Shining a light on the affected area will cause the sensitised skin cells to become inflamed and be replaced by healthy cells. Your doctor will prepare your skin by scraping off the crusted surface of your actinic keratoses lesions and applying a special cream, which contains a chemical that is only absorbed by sun-damaged cells. A special light is then shone on the area to activate the chemical and destroy the sun-damaged cells. If necessary, the treatment can be repeated. However, this treatment can be quite painful.
If you have thickened and horn-like actinic keratoses lesions, your GP or dermatologist may advise that they are surgically removed. This is done under a local anaesthetic and you will stay awake during the procedure. You may find the anaesthetic injections uncomfortable but pain from the areas will be completely blocked.
The actinic keratoses lesions can be scraped off with an instrument called a curette or may be cut out if your doctor suspects that skin cancer may have developed. All these procedures will leave a scar. Samples can be taken from the actinic keratoses to send to a laboratory for testing. This can confirm your diagnosis and determine whether there are any signs of skin cancer.
Developing actinic keratoses is a sign that your skin is ageing and has been damaged by the sun. You can reduce your risk of developing actinic keratoses, or prevent your condition from becoming any worse, by following the advice below.
If you already have actinic keratoses, keep an eye on your skin every few months for any changes, such as a lesion getting larger or sore. If this happens, see your GP.
Produced by Louise Abbott, Bupa Health Information Team, October 2012.
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