NEW YORKActinic keratoses
should be treated or removed, according to the consensus of the
American Academy of Dermatology, American Cancer Society, and Skin
Cancer Foundation. It is not merely a cosmetic issue,
said Jeffrey Callen, MD, chief of the Division of Dermatology,
University of Louisville. Because of their potential to develop into
skin cancer, these lesions should be regarded as a serious health
problem, he said at a media briefing sponsored by the Academy as part
of its Melanoma/Skin Cancer Detection and Prevention Month.
Dr. Callen said that p53 gene mutations present in actinic keratoses
are similar to those found in squamous cell carcinoma. Forty
percent of squamous cell carcinomas begin as actinic keratoses, but
most people do not seek treatment for these skin lesions, he said.
He said that physicians need to raise awareness of the connection
between actinic keratoses and squamous cell carcinoma and to treat
the sun-induced scaly patches early.
Although it is possible to diagnose an actinic keratosis on the
basis of clinical appearance, it can be difficult to distinguish an
actinic keratosis from a squamous cell carcinoma without a biopsy.
Since some actinic keratoses will progress to squamous cell
carcinoma, patients should see a dermatologist when they or their
primary caregivers are in doubt, Dr. Callen said.
Those at greatest risk for progression are the elderly and those with
compromised immune systems, including people with HIV disease, organ
transplant patients, and others on immunosuppressive therapies. As
individuals in these risk groups live longer, their impaired immune
surveillance may not handle actinic keratoses as effectively as those
in whom the immune system is intact. Actinic keratoses may also be a
marker for other cancers, Dr. Callen pointed out.
There is a wide selection of treatments available for actinic
keratoses, ranging from destruction with liquid nitrogen and chemical
or cryogenic peels; chemotherapy with such agents as fluorouracil,
tretinoin, interferon, and calcitriol; and removal through curettage
(with or without electrosurgery), dermabrasion, and lasers. A new
treatment pending FDA approval involves photodynamic therapy.
Dr. Callen declined to recommend a particular therapy, stating that
physician and patient must decide which is the most appropriate
treatment for a given lesion. Location, number, and patient lifestyle
are among factors to be considered.
Actinic keratoses are typically found on sun-exposed areas in older
people, the result of cumulative sun exposure over many years. Sun
avoidance and protection with sunscreens and protective clothing may
prevent new lesions and delay progression to invasive disease, since
UV radiation has been shown to impair immune surveillance, Dr. Callen said.