Actinic Keratosis

Actinic keratosis is a pre-malignant skin disease. Here's how to prevent it and improve your quality of life.

Written and verified by la médico Sandra Golfetto Miskiewicz.

Last update: 16 August, 2021

Actinic keratosis is a skin disease that occurs in areas of skin exposed to the chronic sun, creating an abnormal intraepidermal proliferation of keratinocytes. These are the cells that predominate in the most superficial layer of the skin.

For this reason, it’s most often seen on the face, the back of the neck, and on the hands and forearms. It’s the third most frequently treated skin disease by dermatologists.

Although it doesn’t represent a risk to life, if it isn’t treated it can evolve into a malignant lesion known as squamous cell carcinoma. The greater the number of skin lesions, the greater the risk of developing into cancer.

Symptoms and risk factors of actinic keratosis

This skin disease manifests as lesions that are observed in regions of the body exposed to the sun and have the following characteristics:

• They’re dry, flaky, or rough.
• They’re between 1 and 2 centimeters in size.
• The color is similar to that of the surrounding skin, reddish or brown.
• They can cause itching, pain or bleeding in minor cuts such as when shaving.

The evolution of this disease is variable. Some studies show how they can disappear spontaneously (25% of cases), how they can persist without developing into cancer (15 to 53%) or even advance to squamous cell carcinoma.

Known risk factors include the following:

• Age over 60 years
• Male gender
• Fitzpatrick phototype I and II white skin
• Exposure to ultraviolet (UV) rays
• History of actinic keratosis in the past or skin cancer
• Genetic diseases such as xeroderma, Rothmund’s or Bloom’s syndrome

Actinic keratosis diagnosis

If there are skin lesions with the aforementioned characteristics, a dermatologist should be consulted. The doctor will ask questions about your medical history and degree of sun exposure.

They’ll then perform a complete and detailed physical examination of the lesions, paying particular attention to the number, size, and distribution. Sometimes you can use a dermatoscope, which allows you to appreciate the depth and extent of the spots.

A shave or punch biopsy will be considered. This decision is reserved for the following cases:

• Uncertain diagnosis
• Patients without response to treatment
• To assess whether actinic keratosis has progressed to squamous cell carcinoma

There are variants or types of actinic keratosis that can be differentiated clinically by the doctor. These are hyperkeratotic, atrophic, pigmented, and lichenoid actinic keratoses.

Differential diagnostics

Although the diagnosis is made clinically, sometimes the lesions can resemble other skin conditions. Here are some of the similar conditions:

• Seborrheic keratosis
• Bowen’s disease
• Basal cell carcinoma of the skin
• Discoid lupus erythematosus
• Solar lentigo

Treatment of actinic keratosis

There are two main groups of treatments: treatment for isolated lesions and also for cancerization. The first form treats lesions individually, while the second addresses keratosis when it has spread with multiple lesions.

For the treatment of isolated lesions the options are the following:

• Cryotherapy: Freezing of lesions using liquid nitrogen.
• Curettage or scraping: Removing the lesion.
• Surgery: The removal of the lesion for the histopathological study if the diagnosis is unclear or if squamous cell carcinoma is suspected.

Instead, to apply a field of cancerization, the following are available:

• Dermabrasion: The use of abrasive material to remove superficial layers.
• Ablative laser peel: The removal of the outer layer of the skin and warms the underlying skin, stimulating the growth of new collagen fibers.
• Chemical peel: Topical use of a caustic agent, such as trichloroacetic acid.
• Photodynamic therapy: Topical use of a photosensitizing substance that is exposed to a specific wavelength of light.
• Topical medications: 5-fluorouracil (5-FU), imiquimod (IMQ), ingenol mebutate (IM).

What can you do if actinic keratosis has already been diagnosed?

To prevent the progression and worsening of symptoms, the Skin Cancer Foundation proposes some recommendations:

• A complete physical checkup once a month. This consists of routinely examining yourself once a month in front of a mirror to evaluate the appearance of new spots. If you find something abnormal, you’ll need to go to the dermatologist. Some doctors recommend taking photos periodically to follow the evolution of injuries.
• Annual visit with the dermatologist: An evaluation by an expert is also important. Annual consultations with a dermatologist shouldn’t be forgotten, despite not observing changes in the actinic keratosis lesions.
• Apply prevention habits: The best way to prevent and treat actinic keratosis is to reduce sun exposure by using sunscreen with at least 30 SPF (sun protection factor). Wear long-sleeved clothing that covers most of the skin, as well as hats and sunglasses.

Don’t ignore the warning signs

Actinic keratosis is a common pre-malignant skin lesion. Even if it doesn’t progress, it has a great impact on the quality of life of people who suffer from it, due to the burning sensation, itching, and bleeding that sometimes accompanies the spots.

Everyone who has the condition should be in contact with a dermatologist. In addition, it’s a priority to reduce exposure to UV rays.