Actinic Keratoses

Actinic keratoses typically appear as rough, scaly patches on sun-exposed areas of the skin, such as the face, scalp, ears, neck, backs of the hands, and forearms. When such changes present on the lips, it is called actinic cheilitis. Actinic keratoses are usually red or pink in color and may feel rough or sandpaper-like to the touch. In their early stages, thin actinic keratoses are often easier to feel than to see.

Actinic keratoses develop primarily as a result of prolonged or repeated exposure to UV radiation from the sun or artificial sources such as tanning beds. UV radiation damages the DNA in skin cells, leading to genetic mutations that disrupt normal cell growth and differentiation processes. Several factors contribute to the development of actinic keratoses:

• Sun Exposure: Chronic exposure to sunlight, especially during peak UV radiation hours (typically between 10 a.m. and 4 p.m.), is the primary risk factor for actinic keratoses.
• Fair Skin: People with fair skin, light-colored eyes, and blond or red hair are more susceptible to sun damage and have an increased risk of developing actinic keratoses. This is because fair skin has less melanin, the pigment that provides natural protection against UV radiation.
• Age: Actinic keratoses become more common with age, as the cumulative effects of sun exposure over a lifetime increase the likelihood of developing these lesions. Older individuals are more likely to have actinic keratoses.
• History of Sunburns: A history of sunburns, particularly during childhood or adolescence, significantly increases the risk of developing actinic keratoses later in life.
• Weakened Immune System: Individuals with a weakened immune system, such as organ transplant recipients, HIV/AIDS patients, or those taking immunosuppressive medications, are at higher risk of developing actinic keratoses due to impaired immune surveillance and decreased DNA repair mechanisms in the skin.

Actinic keratoses are usually diagnosed through a medical history and physical exam. Touching the skin closely to feel for rough patches can help early diagnosis. If there is a concern for progression to a squamous cell carcinoma, a biopsy may be recommended. During a skin biopsy, a small sample of tissue is removed from the suspicious lesion under local anesthesia (numbing) and sent to a laboratory for analysis. The tissue is examined under a microscope to confirm the diagnosis of actinic keratosis or evaluate for early signs of squamous cell carcinoma.

While actinic keratoses themselves are not cancerous, they should be evaluated and treated by a dermatologist to reduce the risk of progression to skin cancer. Preventive measures to reduce the risk of developing actinic keratoses and other sun-related skin damage include avoiding prolonged sun exposure, using broad-spectrum sunscreen with a high sun protection factor (SPF), wearing protective clothing and hats, seeking shade during peak sun hours, and avoiding indoor tanning beds.

Dedicated treatment options for actinic keratoses include:

• Cryotherapy (freezing one or multiple actinic keratoses with liquid nitrogen)
• Curettage (scraping off the actinic keratosis, especially for very thick lesions)
• Topical medications (such as fluorouracil, imiquimod, or diclofenac)
• Chemical peel
• Photodynamic therapy (using a photosensitizing agent and light to destroy abnormal cells): This treatment is effective when there are too many actinic keratoses to treat individually.
  • Topical medications, chemical peels, or photodynamic therapy can be used as a field therapy to comprehensively treat larger fields of precancers and areas of significant sun damage and avoid multiple localized curettage or cryotherapy procedures.