An actinic keratosis (plural: actinic keratoses) is a common skin growth. In fact, AK treatment is one of the most common reasons that people visit the dermatologist.
AKs are caused by years of unprotected exposure to ultraviolet radiation from the sun or indoor tanning beds.
AKs are considered precancerous growths. If left untreated, they may turn into a type of skin cancer called squamous cell carcinoma, the second most common form of skin cancer. When detected early, SCC is highly treatable.
It is important to see a board-certified dermatologist if you suspect you have an AK.
WHAT DO AKs LOOK LIKE?
AKs may range in size from as small as a pinhead to larger than a quarter. While many AKs share common qualities, not all AKs look the same. They may appear on the skin as:
- Dry, scaly, rough patches.
- Skin-colored patches that feel gritty, like sandpaper. (It may be easier to feel this type of AK than to see it.)
- Red bumps.
- Thick, red, scaly patches or growths.
- Crusted growths that can vary in color from red to brown to yellowish black. AKs can be itchy, tender or painful. They may bleed, but this is uncommon.
Sometimes an AK grows rapidly upward, resulting in a growth that resembles the horn of an animal. When this happens, the AK is called a "cutaneous horn." Horns can vary in size from that of a pinhead to that of a pencil eraser or even larger. Some horns grow straight, while others curve. Cutaneous horns often form on the ears, face and the backs of the hands.
When AKs develop, they tend to appear on skin that receives a lot of sun exposure, including the:
- Forehead, neck, chest and ears.
- Scalp, especially a bald scalp.
- Arms and hands.
- Lower legs, especially in women.
AKs also commonly form on or at the border of the lips. Known as "actinic cheilitis," this type of AK looks like a white or grayish scaly patch, and it can make the distinction between the pink part of the lip and the surrounding skin become blurred. Lips affected by actinic cheilitis also may appear dry or cracked.
AKs may seem to disappear for weeks or months and then return. Left untreated, the damaged cells can continue to grow and may develop into skin cancer. This makes treatment important.
WHO GETS AKs?
Most AKs appear in adults older than 40. However, people who use indoor tanning beds or live in sunny areas, like Florida or California, may develop AKs on their skin even earlier. Individuals with fair skin, light-colored hair and light- colored eyes have a higher risk of getting AKs than the general population, as do individuals with weak immune systems or those with conditions that make them sensitive to the sun’s UV rays.
HOW DOES A DERMATOLOGIST DIAGNOSE AKs?
A board-certified dermatologist can diagnose most AKs simply by examining the skin. Sometimes AKs are barely visible and are noticed earlier by touch. Some dermatologists may use a magnifying light called a dermatoscope to examine the suspected AK.
In some cases, a biopsy may be needed to ensure that skin cancer has not developed.
Your dermatologist can perform a biopsy during an office visit. Using local anesthesia, the doctor will remove all or part of the suspected AK. The removed tissue will be examined under a microscope.
HOW DOES A DERMATOLOGIST TREAT AKs?
When detected early, AKs are highly treatable. A board-certified dermatologist may use more than one type of therapy to treat AKs, and regular visits to your dermatologist may be required.
Treatments that a board-certified dermatologist can perform in his or her office include:
- Cryotherapy, during which the doctor destroys AKs by freezing them with liquid nitrogen. This is the most common treatment for AKs.
- Curettage, which involves removing AKs via cutting or scraping. This may be combined with electrosurgery, which uses electric current to generate heat that destroys these precancerous skin cells.
- Photodynamic therapy, during which the doctor applies a light-sensitive solution to the skin and exposes it to a special light to destroy AKs.
- Chemical peels, which involve the application of a chemical solution that penetrates the skin to destroy AKs.
- Laser skin resurfacing, which utilizes a laser to remove AKs.
Your dermatologist also may prescribe one of the following medications for you to apply to your skin at home. Some treatments may need to be repeated if the AK recurs or if there is a lot of sun damage.
- 5-fluorouraciL: After you apply this chemotherapy cream to your AKs, the skin will become raw and irritated, and healthy skin will appear as it heals.
- Imiquimod cream: This immunotherapy medication works with your body’s immune system to destroy AK cells. It may cause redness, irritation and swelling, which will go away as the skin heals.
- Ingenol mebutate gel: This medication boosts the immune system while also providing chemotherapy treatment. It may cause redness, irritation and swelling, which will go away as the skin heals.
- Diclofenac sodium gel: This nonsteroidal anti-inflammatory medication is used to treat skin with many AKs, which usually fade about 30 days after treatment is complete.
Additional in-office treatments may be necessary after treatment with topical medication, especially for thicker AKs. Research into other potential AK treatments is ongoing. No one treatment works on all AKs.
Actinic keratoses on the scalp
HOW CAN I PREVENT AKs?
You can help prevent AKs and reduce their risk of returning after treatment by protecting your skin from exposure to UV light:
- Seek shade when appropriate, remembering that the sun’s rays are strongest between 10 a.m. and 2 p.m. If your shadow is shorter than you are, seek shade.
- Wear protective clothing, such as a lightweight long-sleeved shirt, pants, a wide-brimmed hat and sunglasses, when possible.
Generously apply a broad-spectrum, water-resistant sunscreen with an SPF of 30 or higher.
Broad-spectrum sunscreen provides protection from both UVA and UVB rays.
- Use sunscreen whenever you are going to be outside, even on cloudy days.
- Apply enough sunscreen to cover all exposed skin. Most adults need about 1 ounce – or enough to fill a shot glass – to fully cover their body.
- Don’t forget to apply to the tops of your feet, your neck, your ears and the top of your head.
- Reapply sunscreen every two hours when outdoors, or after swimming or sweating.
- Protect your lips by applying a lip balm with an SPF of 30 or higher.
- Take care around water, snow and sand. These reflect and intensify the sun’s damaging rays.
- Avoid tanning beds. UV light from tanning beds can cause skin cancer and early skin aging.
- Consider using a self-tanning product if you want to look tan, but continue to use sunscreen with it. It’s also important to perform regular skin self-exams to look for new or suspicious spots on your skin.
See a board-certified dermatologist if you notice any growth that:
- Starts to itch or bleed.
- Becomes noticeably thicker.
- Changes in size, shape, or color.
- Remains or recurs after treatment.
A board-certified dermatologist is a medical doctor who specializes in the diagnosis and medical, surgical and cosmetic treatment of skin, hair and nail conditions. To learn more about actinic keratoses or to find a board-certified dermatologist in your area, visit www.aad.org/AKs or call toll-free (888) 462-DERM (3376).
Visit the AAD website SpotSkinCancer.org to:
- Learn how to perform a skin self-exam.
- Download a body mole map for tracking changes on your skin.
- Find free SPOTme® skin cancer screenings in your area.
- Share your skin cancer story, if you or a loved one has been affected by skin cancer.
- Download free educational materials to share with your family and friends, or in your community.
All content solely developed by the American Academy of Dermatology.
Copyright © by the American Academy of Dermatology and the American Academy of Dermatology Association.
Images used with permission of the American Academy of Dermatology National Library of Dermatologic Teaching Slides
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