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Updated August 05, 2015.

An actinic keratosis (AK) is a skin growth that develops as a result of sun exposure over many years. AK is the second most common condition treated by dermatologists and is the most common in the Medicare population. Actinic keratoses are of concern because a percentage of them turns into squamous cell carcinoma, the second most common form of skin cancer. It is very difficult to distinguish between benign skin growths and cancerous ones, so it’s always best to see a dermatologist whenever you notice any changes in your skin.

What is actinic keratosis?

An actinic keratosis is a scaly, rough growth on the skin that enlarges slowly and is not typically associated with any other signs or symptoms. These lesions can become painful, inflamed or itchy, and can bleed as they progress to invasive carcinoma. The growth may be flesh-colored or range in color from pink to red to brown. They most often appear on parts of the body that are frequently exposed to the sun, such as the face, scalp, neck, back of hands, and forearms. Most people who develop these growths will have several of them present.

Cause

Actinic keratoses form when the skin has been badly damaged by ultraviolet rays from the sun or indoor tanning beds. These growths tend to grow slowly over many years.

Symptoms

Actinic keratoses vary greatly in appearance. The characteristics of an actinic keratosis may include:

• A patch of skin typically less than 1 inch in diameter that is dry, scaly or rough in appearance
• Flat or slightly raised area on the epidermis (top layer of the skin)

• Itching or burning sensation in or around the growth
• Hard, wart-like texture

In some cases, an actinic keratosis does not look very different from the surrounding area and may be mistaken for a dry patch of skin or other skin problem. For this reason, it’s important to consult with a dermatologist whenever a change in skin texture or appearance is observed. Early detection and treatment of an actinic keratosis can prevent skin cancer from forming.

Risk factors

Anyone who is exposed to ultraviolet rays can develop an actinic keratosis. Some people, however, are more likely to develop the condition. The risk factors for developing actinic keratoses include:

• Being over the age of 40
• Living in a sunny climate
• Having an occupation where most of the day is spent outdoors
• Being frequently exposed to the sun or having a history of sunburns
• Having a tendency to burn easily or get freckles when exposed to sunlight
• Having pale skin, light-colored eyes, and red or blond hair
• Having a history of skin cancer or an actinic keratosis

Diagnosis

An experienced dermatologist is typically able to diagnose an actinic keratosis through visual examination alone. In some cases, the doctor may choose to perform a skin biopsy to confirm the diagnosis. This involves taking a small sample from the affected area and sending it to a lab for analysis. Biopsies are typically performed using a local anesthetic to prevent discomfort.

Dermatologists also recommend that all individuals conduct regular skin self-exams so they are able to detect any changes in skin condition, such as the appearance of an actinic keratosis, and seek treatment promptly. 

Treatments

There is no way to determine whether or not an actinic keratosis will develop into squamous cell carcinoma, so most dermatologists recommend prompt treatment of any actinic keratosis as precaution against later developing skin cancer. There are a variety of methods available for treating or removing actinic keratoses. The treatment recommended depends upon the location of the actinic keratoses and the number of growths present.

Removal procedures

If only a few growths are present, doctors typically recommend individual removal of the actinic keratoses. The two most common removal methods are cryotherapy and curettage. Cryotherapy involves applying a very cold substance to the surface of the lesion. Within a few days, the skin will begin to blister and peel, causing the lesion to slough off and allowing new, healthy skin to form in its place. During a curettage procedure, the doctor will use a special device called a curette to carefully scrape away the actinic keratosis. This specimen may then be sent to the lab to ensure that the lesion isn’t cancerous.

Topical medication

If a patient has several growths, a topical medication may be prescribed to treat the entire area. The topical medications most frequently prescribed to treat actinic keratoses include:

• Ingenol mebutate gel
• Diclofenac gel
• Fluorouracil cream
• Imiquimod cream

The use of these topical creams usually causes the ares to become red and inflamed. Some patients may even experience crusting, skin breakdown and pain. These symptoms usually subside within two weeks after application.

Photodynamic therapy

This relatively new and promising therapy uses a laser to destroy affected skin cells. During the procedure, the doctor will first apply a photosensitizing solution to the actinic keratosis. Next, a laser will be used to destroy the targeted area. Several treatments may be required to fully remove the actinic keratosis.

 AK are extremely common and are one of the most preventable diseases treated by dermatologists. Treating these lesions early is key to preventing their development into invasive skin cancer.