Actinic Keratoses (Precancers) - Western SummaryWestern Medicine Summary

Western Medicine

Western Summary

Actinic keratoses, also known as solar keratoses, are rough lesions that develop as a result of chronic sun overexposure. The Western approach to actinic keratoses involves destruction of the lesions either through the use local treatment or the use of field therapy. 

Treatment Philosophy

The goal with treatment is to eliminate the risk of cancer from developing from the AK. There are many different ways to accomplish this including topical medications or procedures in a healthcare professional’s office. Whether a patient has developed one or many AKs, all patients should use sun protection to avoid developing additional lesions. The use of sunscreen, avoidance of the sun during the most direct sunlight, and wearing clothing to cover the skin are great sun protective measures that will significantly decrease the likelihood of developing AKs and skin cancer.

Symptoms

They often start as a rough, scaly papule on the skin that can be difficult to see and described as feeling like sandpaper. Often times, people will simply notice a rough patch that does not seem to go away with time, moisturizers, or picking. As they progress, they become more visible and can develop redness and a thicker scaly surface. They can be asymptomatic, or can be associated with itch, pain and bleeding.

Causes

Sun exposure causes mutations in superficial skin cells (known as keratinocytes). Normally, keratinocytes have several defenses to repair this damage and prevent the mutation from overtaking the cells. Unfortunately, with excessive sun exposure and damage, these mutations become too much for the cell’s repair systems to keep up. This leads to the formation of AKs. Although they are not considered a skin cancer, they are considered pre-cancer lesions that can progress into squamous cell carcinoma, one type of a skin cancer. The risk for any one AK to progress to a squamous cell carcinoma skin cancer has been estimated to range from a low of 0.1% to a high of 20% if left untreated.[1]

Risk Factors

Your body 

  • Age: The incidence of skin cancer increases as you age due to greater accumulated sun exposure.
  • Suppressed immune system: If you have a medical condition or take medication that decreases the strength of your immune system, this can also potentially increase your risk of actinic keratoses. We know that people who have had organ transplants are at particularly high risk.
  • Genetics: Fair skin and certain genetic risk factors can also put you at an increased risk for UV exposure and the development of actinic keratosis.

Environment 

  • Exposures: Certain exposures such as radiation and other chemicals have been associated with an increased incidence of squamous cell carcinoma and its precursor, actinic keratoses.
  • Ultraviolet (UV) Light: Ultraviolet light from the sun and indoor tanning bed use both increase the chance of developing actinic keratoses and skin cancer.

Treatments

A physician has many tools to help eradicate an actinic keratosis. The choice of treatment often depends on how many actinic keratoses are present and over what surface area that determines the best type of treatment. 

Medications

  • Sunscreens: Physical blockers such as titanium dioxide and zinc are preferred to chemical based sunscreens, but the use of ANY sunscreen on repeated basis throughout the day is better than not using anything.
  • Topical medications: Topical medications like 5-fluororacil, imiquimod, and ingenol mebutate, to name just a few, can be used alone or in combination with one of the other treatments discussed.

Procedures and surgery

  • Cryotherapy: Cryotherapy uses liquid nitrogen to freeze the small growth off the skin. Physicians can use a metal container to spray the lesion or may use a Q-tip to apply the liquid nitrogen.
  • Curretage: Curretage is the act of scraping off a portion of the skin. A physician may use a sharp blade to remove an actinic keratosis.
  • General facial resurfacing: Chemical peels, laser resurfacing, and photodynamic therapy can help treat the entire face at once.

Lifestyle changes

  • Lifestyle: Photoprotection is the best thing you can do on a daily basis to help prevent the occurrence of actinic keratoses and other skin cancers. This includes the use of sunscreen and photo-protective clothing such as long sleeves and hats. Avoid the use of tanning beds. If possible, avoid direct sunlight between the hours of 10am and 4pm as this is when the UV rays are most significant—walk in the shade or stay indoors.
  1. Costa C, Scalvenzi M, Ayala F, et al. How to treat actinic keratosis? An update. J Dermatol Case Rep.2015;9(2):29-35; PMID: 26236409 Link to research.