An actinic keratosis (pronounced ak-tin-ik ker-uh-toe-sis) is a scaly, rough patch of skin that has been damaged from years of sun exposure. It's a very common skin condition, but there's a small chance these dry patches could become skin cancer. This article will explain potential causes, treatments, when to see a doctor and how to prevent further skin damage.
Actinic Keratosis Treating sun damaged skin
What is an actinic keratosis?
Actinic keratoses are crusty patches of skin caused by sustained sun damage. The condition is also known as solar keratosis because the terms actinic and solar are from Greek and Latin, respectively, for 'sunlight-induced', with keratosis meaning thickened skin. An actinic keratosis may be singular but there are usually multiple keratoses. It is not contagious.
These patches of sun damaged skin are most commonly found on sites frequently exposed to sunlight, such as the face, scalp, lips, ears, neck, back of the hands and forearms. A solar keratosis can take years to develop, slowly enlarging from a small spot that is easier to feel than see, into a more noticeable, irritable patch.
Actinic keratosis symptoms
While the appearance can vary, actinic keratosis symptoms and signs include:
- Rough, dry or scaly patches of skin, similar to sandpaper
- A flat or slightly raised plaque on the top layer of skin between 1cm to 2cm in size
- Colour as varied as pink, red, brown, white, yellow, skin-toned or a combination of colours
- Itchy, sore or burning feeling in the affected area
- For some patients, a hard, warty surface
When to seek medical advice
Actinic keratoses are not cancerous themselves and only 5-10% turn into skin cancer. However these patches can develop into squamous cell carcinoma, which is the second most common type of skin cancer.
Though the likelihood of cancer is low, you should be extra careful and see your doctor if you think you have a solar keratosis. It's best to get them diagnosed and treated early, especially if the lesion is on the head or neck, where skin cancers can be more aggressive.
You should also get them examined if you notice patches hardening, bleeding, rapidly enlarging, changing colour, feeling tender or developing into a lump.
Actinic keratosis vs seborrheic keratosis
Though they have a similar name, there is a big difference between seborrheic keratosis and actinic keratosis. Seborrheic keratosis is a common sign of skin ageing in the form of a harmless, warty spot that isn’t known to develop into skin cancer and is not necessarily a sign of sun damaged skin. Actinic keratosis, on the other hand, has the potential of becoming cancerous. Dermatologists should be able to distinguish between the two quite easily.
Actinic keratosis causes
Solar keratosis is caused by cumulative exposure to ultraviolet rays from the sun and/or tanning beds over many years. If you already have an actinic keratosis you're likely to develop more keratoses in the future.
While anybody can suffer from actinic keratoses, lesions are more likely to appear if you
- are aged 40 and over
- have lived in hot climates
- usually freckle or sunburn easily
- are fair or red-haired with blue or light-coloured eyes
- show other signs of photoaging skin
- spend long hours outdoors
- suffer from human papilloma virus
- have a defective immune system due to chemotherapy, leukemia, AIDS or organ transplant medications
While they are not hereditary some of the risk factors for developing solar keratoses do run in families – for instance if a person has red or fair hair and a tendency to burn easily instead of tanning.
Actinic keratosis treatment
On some occasions actinic keratosis treatment is not required because small patches will disappear without treatment, but the majority remain. Solar keratoses are normally removed due to the risk of skin cancer developing, or because they are painful, itchy or unsightly. Your doctor may refer you to a skin specialist, who could recommend one of the following actinic keratosis treatments:
- Cryosurgery: Liquid nitrogen is applied to freeze off the growth using a spray gun or cotton swab. This can be repeated if necessary, and varies according to lesion location. Healing can take 5-10 days on the face, 3-4 weeks on the hands and 6 weeks or more on the legs.
- Electrocautery and curettage: With the area numbed before the procedure, a surgeon applies an electric current to cauterise (burn) the growth and kill the affected skin cells. For curettage, the burnt growth is then scraped off using a curette, a scoop-like surgical instrument. A specimen is then sent for pathological examination. Depending on the growth location, healing can take several weeks or longer.
- Excision: This involves cutting the lesion from the skin, and your doctor may choose to remove extra tissue around or under the growth to ensure the actinic keratosis has been removed. Stitches may be required, depending on the size of the wound, in which case the procedure leaves a permanent scar.
- Creams: In some cases, prescription gels or creams can be prescribed for actinic keratosis treatment and areas of sun damage. These are most effective on facial skin. Pretreatment with keratolytics (like urea cream, salicylic acid ointment or topical retinoid), and thorough skin cleansing improves this solar keratosis treatment.
Actinic keratosis prevention
Solar keratoses are prevented by strict sun protection. Learn more about the effect of sun on your body with our dedicated sun protection article.
If you already have actinic keratoses you must avoid further sun damage to lower your chances of developing skin cancer. To prevent more patches from appearing, follow these tips:
- Before going out into the sun, apply a sunscreen with an SPF factor of at least 30 and reapply regularly to avoid sunburn
- Limit your time in the sun, especially when the sun is at its hottest between 11am-3pm, and seek shade to protect your skin against UV exposure, even when it’s cloudy
- Wear a hat or clothing that covers your legs and arms when in the sunlight
- Do not use sunbeds or sunlamps
- Check your skin regularly and report any changes to your doctor