Actinic keratoses (AK’s) are considered the earliest stage in the development of skin cancer. They are common lesions of the epidermis (outermost layer of the skin), and are caused by long-term exposure to sunlight. AK’s are most likely to appear after age 40, but may be found in persons as young as the teens and twenties. The most significant predisposing factors to AK’s are fair skin and long-term sun exposure.
AK’s are caused by changes in keratinocytes (skin cells) and the skin becomes rough, scaly, or mottled; and occasionally, the skin may develop bumps or small horn-like growths. Further changes in cell growth can turn AK’s into squamous cell carcinoma, a type of skin cancer.
AK’s are found on sun-exposed skin, most commonly on a fair-skinned person, middle-aged or older. They can be found on the face, sides of the forehead, the ears, the scalp of bald men, and the backs of the hands. The typical AK is a dry, scaly, rough textured, skin-colored to reddish-brown patch, or slightly elevated bump. An AK may range from the size of a pinhead to larger than a quarter. Skin-colored AK’s may be easier to feel than to see and may be noticed more by touch because they have a sharp, hard scale and feel like sandpaper. They may be sensitive or tender. Wrinkling, furrowing, and other signs of sun damage may be present with an AK. An AK at any location may seem to disappear at times for weeks or months, and return at the same place. If they are picked off, they grow back. An AK can also appear as a diffuse, scaling lesion on the lower lip that dries and cracks open. Prevention of AK’s should begin early in life. Sun damage to unprotected skin begins in childhood and puts the child at risk for actinic keratoses and skin cancer later in life. However, it is never too late to initiate prevention of new actinic keratosis lesions in adulthood.
The basics of prevention are:
- Avoid excessive exposure to sunlight during peak sunlight hours (10 AM to 4 PM).
- Wear clothing that covers arms and legs, and wear a wide brimmed hat with at least a 4-inch brim.
- Use a sunscreen moisturizer with a sun protection factor (SPF) of 15 or higher daily, and apply at least 20 minutes prior to sun exposure for maximum sun protection.
- Select a broad-spectrum sunscreen that provides both UVA and UVB protection, and reapply sunscreen every 1 hours when swimming or sweating or every 1.5 hours when outdoors, even on cloudy days.
Treatment of Actinic Keratoses
Liquid nitrogen is used for the treatment of actinic keratoses. This is a cold cryosurgery spray procedure that freezes the top layer of atypical cells, which flake off and are replaced by new skin. Patients may experience a short-lived stinging or burning sensation after the treatment. Although short-term skin redness is the chief side effect, flat white spots may occasionally occur. Makeup may be used to cover up the redness. Patients may wash your face and swim afterwards; no special aftercare is required. If blistering occurs, this may be treated with Vaseline.