Actinic keratosis (AK) is a precancerous condition that affects the skin, usually on areas of the body that are frequently exposed to sunlight, such as the face, scalp, neck, and hands. It is caused by long-term exposure to ultraviolet (UV) radiation from the sun, which leads to the abnormal growth of cells in the epidermis, the outermost layer of the skin.
AK typically appears as a small, scaly or crusty patch of skin that can be pink, red, brown, or flesh-colored. The lesion may be flat or raised, and can feel rough or itchy. AKs are usually harmless, but in some cases they can progress to become squamous cell carcinoma, a type of skin cancer.
Risk factors for developing AKs include:
- Age: AKs are more common in older adults, especially those over the age of 60.
- Skin type: People with fair skin, light hair, and blue or green eyes are more susceptible to AKs.
- Sun exposure: Prolonged exposure to sunlight or artificial sources of UV radiation, such as tanning beds, increases the risk of developing AKs.
- History of skin cancer: People who have had skin cancer in the past are more likely to develop AKs.
Treatment for AKs typically involves the removal of the affected skin cells. This can be done through a variety of methods, including cryotherapy (freezing the lesion with liquid nitrogen), topical medications, curettage (scraping off the lesion with a sharp tool), or photodynamic therapy (using light to activate a medication that destroys the abnormal cells).
Prevention of AKs involves protecting the skin from excessive sun exposure. This can be achieved by wearing protective clothing, including hats and long-sleeved shirts, using sunscreen with a high SPF, and avoiding excessive exposure to the sun during peak UV radiation hours (10am-4pm).