An actinic keratosis, also known as a solar keratosis, is a common premalignant skin lesion. An actinic keratosis occurs when the cells that comprise 90 percent of the epidermis, the keratinocytes, change their size, shape or organization in a process called cutaneous dysplasia. This alters the texture of the skin surface and may extend deeper, into the dermis.
Causes of an Actinic Keratosis
Such a lesion is typically caused by chronic exposure to sunlight, particularly ultraviolet light and is therefore mainly found on areas of the body most frequently exposed to the sun. While not a skin cancer, an actinic keratosis, left untreated, may develop into a squamous cell carcinoma, a form of skin cancer capable of metastasizing and even resulting in death. Although not dangerous in itself, an actinic keratosis must always be taken seriously and examined and treated by a dermatologist.
Symptoms of an Actinic Keratosis
An actinic keratosis appears as a scaly reddish or tan lesion on the epidermis, or surface layer of the skin. It may manifest as rough or scaly skin, bumps, mottled patterns, or protrusions called cutaneous horns. Actinic keratoses usually appear on the face, including the ears and lips, or on the neck, arms and hands. The lesions may range in size from a pinpoint to several centimeters in diameter and may be yellow, brown, red or violet in color, and smooth, wrinkled or furrowed in texture.
Risk Factors for an Actinic Keratosis
Fair-skinned individuals, aged 40 to 50 years of age, are more prone to actinic keratosis. Nonetheless, individuals of any age may develop such lesions, particularly in warm, sunny climates. Teenagers are often diagnosed with the condition. Actinic keratosis is also more likely to occur in individuals who spend a great deal of time in the sun, or who frequent tanning parlors.
Diagnosis of an Actinic Keratosis
A dermatologist should always be consulted about any suspicious lesion on the skin. Unless such a lesion is immediately identifiable by the physician as benign, a surgical biopsy may be performed to determine whether it is premalignant or cancerous. The biopsy procedure is small and painless and takes place in the doctor's office. A pathology report will be available in a week or two to determine whether further treatment is necessary.
Treatment of an Actinic Keratosis
Depending on the location and severity of the lesion, an actinic keratosis may be treated in a number of ways. The patient and doctor will decide on methodology in consultation. These may include:
- Cryotherapy, or freezing
- Curettage, or scraping
- Application of cream or ointment
- Chemical peeling
- Photodynamic therapy using laser light
Prevention of Actinic Keratosis
Because individuals who have had an actinic keratosis are more likely to have another lesion of this type and are also at greater risk of developing a squamous cell carcinoma, they should always opt to have full body checks with their dermatologist at regular intervals. Patients who have been treated for this condition should also avoid sunlight as much as possible. When they are exposed to the sun, they should be careful to wear adequate protection, including sunscreen with an SPF of 30 or higher, protective sunglasses, long sleeves and long pants whenever possible, and wide-brimmed hats. They should also, of course, avoid tanning parlors.