What is an Actinic Keratosis?
An actinic keratosis (AK), also known as a solar keratosis, is a precancerous lesion of the outer layer of the skin (epidermis) that is caused by long-term exposure to sunlight. AK’s are most commonly found on sun-exposed areas of the face, ears, lips, chest, back, arms and hands. Patients with fair skin and light-colored eyes and hair are at greatest risk for developing AK’s. Individuals who are chronically Immunosuppressed by organ transplantation, chemotherapy, or chronic immune-deficiency disorders, are at heightened risk for developing AK’s.
What causes an Actinic Keratosis?
AK’s are caused by chronic exposure to ultraviolet radiation, typically from sunlight. Frequent, long-term tanning bed use can also cause these lesions. Ultraviolet radiation damages the DNA of the keratinocytes (the cells that make up most of the epidermis), altering their normal life cycle. This results in the development of scaly, rough, discolored, painful lesions on the skin. The body’s DNA repair mechanism weakens as patients age, resulting in damaged keratinocytes that escape the immune system’s normal surveillance. AK’s are not life threatening, but if left untreated, have the potential to progress into a squamous cell carcinoma. Squamous cell carcinomas are serious cancers that possess a small potential to metastasis. It is estimated that, if left untreated, approximately 10% of actinic keratoses will develop into a squamous cell carcinoma.
The mainstay of treatment for actinic keratoses is proper sun protection and avoiding excessive sun-exposure. Avoiding outdoor activities between the hours of 11:00 am and 4:00 pm help to prevent development of AK’s. Patients at high risk should make it a daily practice to wear a broad spectrum sunscreen, rated at least SPF-30, on exposed areas of the skin. Sunscreens should be reapplied every two hours during outdoor activities. We recommend purchasing a sunscreen with either Titanium Dioxide or Zinc oxide. Frequent use of sun-protective hats, shades, eyeglasses and clothing also minimize AK development. There are myriad of treatment options including cryotherapy (freezing lesion with liquid nitrogen), curettage, topical chemotherapy (Efudex, Carac, etc…), topical immune modulating therapy, Photodynamic Therapy (PDT), chemical peels and laser resurfacing. We look forward to sharing our expertise and determining to best treatment option for you.