Actinic keratosis (AK), also known as solar keratosis, is one of the most common precancerous lesions of the epidermis (outer layer of skin). It is caused by long-term exposure to sunlight.
Chronic sunlight exposure alters the keratinocytes (cells that make up the majority of the epidermis) and causes areas of your skin to become scaly, rough, discolored, and sometimes tender to the touch. AKs grow slowly and are usually benign (non-cancerous).
Look for areas of your skin that become scaly, rough, discolored, and sometimes tender to the touch.
AKs are most commonly found on sun-exposed areas such as the face, lips, ears, neck, scalp, forearms, and backs of hands.
Chronic exposure to sunlight alters the cells that make up the majority of the epidermis, which can lead to AKs. People who have fair skin and light-colored hair and eyes are at greatest risk.
Individuals who are immunosuppressed, either by cancer chemotherapy treatments or organ transplants, or who have an immunodeficiency disorder, are also considered high risk.
AKs are not life-threatening as long as they are diagnosed and treated in the early stages. Left untreated, aggressive AKs may progress into squamous cell carcinoma, a serious type of skin cancer.
Source: American Cancer Society, 2020
Doctors often diagnose and treat AKs based on clinical appearance alone though sometimes a skin biopsy is needed. If a dermatologist assesses your skin tissue and determines the lesion is an AK, they will discuss several treatment options with you and help you decide which is best.
Common treatment options for actinic keratosis include:
Your treatment may vary based on the number of AKs you have developed, their location, and size. Your age and general health will also be taken into consideration.
To protect yourself from actinic keratosis, the most important prevention measure you can take is to avoid overexposure to sunlight.
You should also inspect your entire body regularly for any skin changes, and routinely visit your physician for a skin examination.
Learn more about recommended prevention and protection techniques from Spot the Spot.
Review information on actinic keratosis or other skin disorders with your dermatologist. Download or print these brochures and bring them to your next appointment.
Source: Skin Cancer Foundation
This is the most common form of skin cancer and usually occurs on sun-exposed areas of the body.
This major cancer arises from the outer layer of the skin and mucous membranes.
The best way to prevent skin cancer is to protect your skin from sun exposure and tanning bulbs.
Practice the ABCDEs and the 5-step self-check to examine your skin for suspicious lesions.
Each type of skin condition looks a bit different. Learn to identify potentially dangerous spots.
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