By Debra Jaliman, MD
Actinic keratosis is the most common precursor to skin cancer. These lesions are most typically found in fair-skinned individuals, and they can appear anywhere on the body or face, even on bald scalps. They are caused by sun exposure and severe sunburns, but they can take years to become apparent. They look like red, scaly patches, and they feel like sandpaper.
Many people shrug it off, thinking it are just a mild cosmetic problem, but actinic keratosis should be treated promptly, because the kesions can turn into squamous cell skin cancer at any moment. The usual treatment is cryosurgery, which uses liquid nitrogen to freeze the lesions, which then typically scab and fall off in a couple of days. Most cases require two sessions of cryotherapy, spaced two weeks apart. It’s a mostly painless procedure, although it may burn a bit.
Topical treatments with prescription creams that patients apply at home are another alternative and are especially useful when there are multiple sites to treat. One of them, 5-FU (5-fluorouracil), is a heavy-duty cream that is actually considered a topical chemotherapy. It’s effective, but it must be applied for several weeks. A common side effect is red and swollen skin, and many people report a burning sensation. Aldara (Imiquimod) is an immune-response modifier which basically stimulates the immune system to kill pre-cancerous cells. It irritates the skin less than 5-FU, but it also takes several weeks. To lessen the chances of irritating the skin, some doctors prefer intermittent Aldara therapy, where patients use it two week on, two weeks off for three cycles. Aldara is frequently used in conjunction with cryotherapy to cover all bases and make sure the lesions are completely eradicated.
All these treatments work, but they do take time—so much time that patients often fail to complete them. Now a new gel may work far faster. I’m proud to say that researchers at Mount Sinai School of Medicine, where I have taught for more than 25 years, have just published a study showing that ingenol mebutate topical gel can take just two or three days, as opposed to weeks, to clear these pre-malignant skin lesions. The interesting thing is that ingenol mebutate is derived from a weed commonly found in Europe and Asia, where it is a traditional folk remedy for skin lesions.
This new topical gel has been approved by the FDA and is sold as Picato, a prescription only medication. Even though some people with multiple lesions may have to use it for a week instead of a couple of days, it seems to irritate the skin far less than Aldara and 5-FU. All in all, it’s an exciting development in dermatology.
Bottom line: A new topical gel may make it far easier to treat actinic keratosis, so don’t put off that visit to your dermatologist.