Alternative Names: Solar keratosis; Sun-induced skin changes - keratosis; Keratosis - actinic (solar)

Causes, incidence, and risk factors:

Actinic keratosis occurs most commonly in fair skin, especially in the elderly and in young individuals with light complexions. The growths occur in sun-exposed skin areas. The growths begin as flat, scaly areas that later develop a hard wart-like surface.

They are classified as precancerous growths. If left untreated, approximately 1% of actinic keratoses develop into squamous cell carcinoma.

Symptoms:

• Rough and dry textured skin lesion
• A macule, patch, or growth on the skin
  • Limited to a discrete area (localized)
  • Located on the face, scalp, back of the hands, chest or other sun-exposed areas
  • Gray, pink, red (erythematous), or the same color as the skin
  • Initially flat and scaly on the surface, becoming slightly raised
  • Becoming hard and wart-like or gritty, rough, and "sandpapery" -- may develop a horn-like texture from overgrowth of skin keratin layer (hyperkeratosis)

The skin lesion may be easier to feel than to see.

Signs and tests:

The health care provider bases the diagnosis on the appearance of the skin growth. A skin biopsy could reveal signs of cancerous changes, if present.

Treatment:

Because actinic keratoses represent precancerous changes, have them examined promptly, and follow the health care provider's advice for treatment.

Growths may be removed by cryotherapy (freezing), electrical cautery (burning), or surgery. Growths may also be treated with topical medications that cause peeling or skin removal, such as topical 5-fluorouracil or imiquimod.

Support Groups:

Expectations (prognosis):

Actinic keratosis itself is benign, but it may develop into skin cancer. Removal of the growth is usually effective.

Complications:

• Squamous cell carcinoma
• Irritation and discomfort of the skin growth

Calling your health care provider:

Call for an appointment with your health care provider if areas of persistent roughness or scaliness develop in sun-exposed skin.

Prevention:

Minimize sun exposure and protect skin from the sun. Wear protective clothing such as hats, long-sleeved shirts, long skirts, or pants. Ultraviolet light is most intense midday, so try to avoid exposure during these hours.

Use high-quality sunscreens, preferably with SPF (sun protection factor) ratings of at least 15. Pick a sunscreen that blocks both UBA and UVB light. Apply sunscreen at least half an hour before exposure, and reapply frequently.

Use sunscreen for winter exposure also.