Actinic keratosis is a small, rough, raised area found on skin that has been in the sun for a long period of time. Some actinic keratoses may develop into a type of skin cancer.
An actinic keratosis is a scaly or crusty bump that forms on the skin surface. They are also called solar keratosis, sun spots, or precancerous spots. Dermatologists call them “AK’s” for short. They range in size from as small as a pinhead to over an inch across. They may be light or dark, tan, pink, red, a combination of these, or the same color as ones skin. The scale or crust is horn-like, dry, and rough, and is often recognized easier by touch rather than sight. Occasionally they itch or produce a pricking or tender sensation, especially after being in the sun. They may disappear only to reappear later. Half of the keratosis will go away on their own if one avoid all sun for a few years. One often sees several actinic keratoses show up at the same time. Keratoses are most likely to appear on sun exposed areas: face, ears, bald scalp, neck, backs of hands and forearms, and lips. They may be flat or raised on appearance.
Why is it dangerous? Actinic keratosis can be the first step in the development of skin cancer, and, therefore, is a precursor of cancer or a precancer. It is estimated that 10 to 15 percent of active lesions, which are redder and more tender than the rest will take the next step and progress to squamous cell carcinomas. These cancers are usually not life threatening, provided they are detected and treated in the early stages.
Causes, incidence, and risk factors
Actinic keratosis is caused by being in sunlight. You are more likely to develop this if you:
- Have fair skin, blue or green eyes, or blond or red hair
- Had a kidney or other transplant
- Take medicines that suppress the immune system
- Spend a lot of time each day in the sun (for example, if you work outdoors)
- Had many, severe sunburns early in life
- Are older
- Actinic keratosis is usually found on the face, scalp, back of the hands, chest, or other sun-exposed areas.
- They begin as flat and scaly areas.
- The color may be gray, pink, red, or the same color as the skin.
- Often, it has a white or yellow crusty “scale” on top.
- Later it develops a hard and wart-like or gritty, rough, surface.
- It may be easier to feel than see.