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Diseases and Conditions
Special to CNN.com
Actinic keratosis is a skin condition characterized by rough, scaly patches on the skin of your face, lips, ears, back of your hands, forearms, scalp and neck. It's caused by frequent or intense exposure to ultraviolet (UV) rays, typically from the sun. Many doctors consider actinic keratosis to be precancerous because it may develop into skin cancer.
Actinic keratoses, also known as solar keratoses, grow slowly and usually cause no signs or symptoms other than patches or small spots on the skin. These lesions take years to develop, usually first appearing in older adults. Left untreated, about one in 10 cases of actinic keratoses develop into squamous cell carcinoma, a serious form of skin cancer.
You can reduce your risk of actinic keratosis by minimizing your sun exposure and protecting your skin from UV rays.
Signs and symptoms
The signs and symptoms of actinic keratosis include:
- Flat to slightly raised, scaly patches on the top layer of your skin
- Lesions on your skin ranging in color from pink to red to brown, or flesh-colored
Patches or lesions caused by actinic keratosis usually are 1 inch or less in diameter and primarily are found on areas exposed to the sun, including your face, lips, ears, back of your hands, forearms, scalp and neck. There may be a single lesion or more. Later, lesions can develop a hard, wart-like surface.
If you have a skin lesion that persists, grows or bleeds, see your doctor.
You're most likely to develop actinic keratosis if you have one or more of these risk factors:
- A history of frequent or intense sun exposure or sunburn
- Pale skin
- Blond or red hair, especially when coupled with blue, hazel or green eyes
- A tendency to freckle or burn when exposed to sunlight
- A weak immune system as a result of chemotherapy, AIDS or an organ transplant
Actinic keratosis may be the first sign of skin cancer. If treated early, almost all actinic keratoses can be eliminated before developing into skin cancer. However, if left untreated these spots or patches may progress to squamous cell carcinoma, a serious form of skin cancer. Actinic keratosis may be the earliest form of squamous cell carcinoma. This type of cancer usually isn't life-threatening if detected and treated early. However, actinic keratoses can grow to be large and invade surrounding tissues, some spreading (metastasizing) to other parts of your body. The more keratoses you have, the greater your chance of developing skin cancer.
It's impossible to tell exactly which patches or lesions will develop into skin cancer. Your doctor or a dermatologist can discuss with you which treatment is appropriate for you.
Treatment options may include:
- Freezing (cryotherapy). An extremely cold substance, such as liquid nitrogen, is applied to skin lesions. The substance freezes the surface skin, causing blistering or peeling. As your skin heals, the lesions slough off, allowing new skin to appear. This is the most common treatment, takes only a few minutes, and can be performed in your doctor's office.
- Creams or ointments. Some topical medications contain fluorouracil, a chemotherapy drug. The medication destroys actinic keratosis cells by blocking essential reactions within them. Another treatment option is imiquimod (Aldara), a topical cream that modifies the skin's immune system to stimulate your body's own rejection of precancerous cells.
- Chemical peeling. This involves applying one or more chemical solutions (trichloroacetic acid, or TCA, for example) to the lesions. The chemicals cause your skin to blister and eventually peel, allowing new skin to form. This procedure may not be covered by insurance, because it's considered cosmetic.
- Scraping (curettage). In this procedure, your surgeon uses a device called a curet to scrape off damaged cells. Scraping may be followed by electrosurgery, in which a pencil-shaped instrument is used to cut and destroy the affected tissue with an electric current.
- Photodynamic therapy. With this procedure, an agent that makes your damaged skin cells sensitive to light (photosensitizing agent) is either injected or applied topically. Your skin is then exposed to intense laser light to destroy the damaged skin cells.
- Retinoids. One drug in this class — the oral drug isotretinoin — is effective in preventing actinic keratosis. However, it's recommended only in high-risk cases because it may cause significant side effects, such as eye and lip inflammation, bone spurs and hair loss, and birth defects if taken during pregnancy. Researchers are investigating two topical retinoids — adapalene and tretinoin — to determine if they may be effective in both treating and preventing the condition.
Talk to your doctor about your treatment options. The procedures have various advantages and disadvantages, including side effects, risk of scarring, and the number of treatment sessions required. Actinic keratosis is usually very responsive to treatment. Afterward you'll likely have regular follow-up visits to check for new patches or lesions.
Prevention of actinic keratosis is important. The condition can be precancerous or an early form of skin cancer. Sun safety is necessary to help prevent development and recurrence of patches and lesions caused by actinic keratosis.
Take these steps to protect your skin from the sun:
- Limit your time in the sun. Avoid staying in the sun so long that you get a sunburn or a suntan. Both result in skin damage that can increase your risk of developing actinic keratosis and skin cancer. Sun exposure accumulated over time also may cause actinic keratosis. In addition to minimizing your time in the sun, set time limits when at the pool or beach or when you're spending time outdoors in the winter. Snow, water and ice all reflect and intensify the sun's harmful rays, and ultraviolet rays are strongest between 10 a.m. and 4 p.m. Clouds block only a small portion of UV rays.
- Use sunscreen. Before spending time outdoors, apply a broad-spectrum sunscreen with a sun protection factor (SPF) of at least 15. Some sunscreens contain substances that block ultraviolet A (UVA) as well as ultraviolet B (UVB) rays. UVA rays penetrate into the deeper layers of your skin and can weaken your skin's immune system; UVB rays cause sunburn and play a significant role in superficial skin cancers. To identify UVA-blocking creams, look on the ingredient labels for avobenzone, titanium, dioxide, and transparent or microdispersed zinc oxide. Use sunscreen on all exposed skin, including your lips. Apply sunscreen 30 minutes before sun exposure, and reapply it every few hours or more often if you swim or sweat. Apply sunscreen to infants or young children before going outdoors and teach older children and teens how to use sunscreen to protect themselves. Keep a bottle of sunscreen in your car, your boat, with your gardening tools, and with your sports and camping gear to remind yourself and your family to use it.
- Cover up. For extra protection from the sun, wear tightly woven clothing that covers your arms and legs and a broad-brimmed hat, which provides more protection than does a baseball cap or golf visor. You might also consider wearing clothing or outdoor gear specially designed to provide sun protection.
- Avoid tanning beds and tan-accelerating agents. Tanning beds emit UVA rays, which are often touted as less dangerous than UVB rays. But UVA light penetrates deeper into your skin, causes actinic keratosis and increases your risk of skin cancer. As for suntan-accelerating products, the Food and Drug Administration warns against their use. Bronzing lotions that produce a tanned look without any sun exposure are a safe choice.
- Be aware of sun-sensitizing medications. Some common prescription and over-the-counter drugs can make your skin more sensitive to sunlight. These include antibiotics; certain cholesterol, high blood pressure and diabetes medications; birth control pills; nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (Advil, Motrin, others); and the acne medicine isotretinoin (Accutane). Ask your doctor or pharmacist about the side effects of any medications you take. If they increase your sensitivity to sunlight, be sure to take extra precautions.
- Check your skin regularly and report changes to your doctor. Examine your skin regularly, looking for the development of new skin growths or changes in existing moles, freckles, bumps and birthmarks. With the help of mirrors, check your face, neck, ears and scalp. Examine the tops and undersides of your arms and hands.