Actinic keratoses are small scaly precancerous lesions that develop from chronic sun exposure. They are extremely common and many treatment options exist for them.
What to expect?
Because AKs have the potential to develop into squamous cell carcinoma, most doctors will choose to treat them. Treatment choice often depends on the number of lesions present, tolerability of the treatment, and the age of the patient.
Treatment options
Destructive Therapy
- Cryotherapy is the most commonly used modality for the treatment of AKs, since it is both quick and effective. Liquid nitrogen is used to freeze the lesion, causing the area of skin to die. A bruise may develop initially, but scarring does not occur.
- Electrodesiccation and curretage is used when other treatments do not work. First the skin will be numbed using a small injection of lidocaine. The lesion will be cut out from the skin and then a tool will be used to stop the bleeding by sending an electric current through the skin. This may be repeated up to 3 times.
- Excision may also be done if other treatment options do not work or if the doctor is concerned that the lesion may be cancerous.
Medical Therapy
- 5-fluorouracil is a topical medication that comes in both a cream and solution form and is used in patients with multiple AKs. It works by destroying the cells in the lesion. The most common formula is 5% cream applied twice daily for a month. This treatment causes inflammation at the site of the lesions, so the AKs may get worse before they get better. In addition, at the start of treatment, you may notice “new” AKs that were not visible before. This will improve as you continue treatment.
- Imiquimod is a topical agent that activates the inflammatory cells in your body so they can destroy the lesion. Imiquimod 5% cream is often applied 2-3 times a week. If you cannot tolerate the inflammation induced by the treatment, you can apply it less often. Recently, a 3.75% formulation was also approved. Similar to 5-fluorouracil, lesions will get worse before they get better.
- Diclofenac sodium 3% gel is a nonsteroidal anti-inflammatory drug used topically for the treatment of AKs. It is applied two times a day for 3 months. This therapy can also be used in combination with cryotherapy.
Prevention
Prevention is very important, especially in those with risk factors or with a history of AKs. The #1 way to reduce the development of AKs is to PROTECT YOUR SKIN with protective clothing (i.e. hats, shirts) and sunscreen with an SPF of at least 30. Sun avoidance between the hours of 10:00 am and 2:00 pm is also recommended.
REFERENCES:
Marks JG, Miller JJ. Actinic Keratosis. In: Lookingbill & Marks’ Principles of Dermatology. 4th ed. Elsevier Inc; 2006:60-62.
Spencer J, Bastile, AL. Actinic Keratosis. eMedicine from WebMD. Updated February 18, 2009. Available at: http://emedicine.medscape.com/article/1099775-overview
Berman B, Amini S, Valins W, Block S. Pharmacotherapy of actinic keratosis. Expert Opin Pharmacother. 2009 Dec;10(18):3015-31.