Reversing the damage
When my father was 11, his family uprooted itself from Burlington, Vt., and moved to Southern California. The reason was straightforward: My father suffered from psoriasis and his doctors said that lots and lots of sunshine was what he needed. For 60 years, he was diligent about following their advice, sunbathing whenever he had the opportunity.
His psoriasis improved, but the years of sun exposure ultimately took their toll. Rough, scaly patches developed on his face and arms -- lesions that were diagnosed as actinic keratoses, an early stage of skin cancer called squamous cell carcinoma.
For nearly a decade, he went regularly to a dermatologist to have them checked, but -- like many people with actinic keratoses -- allowed them to go untreated.
This approach may sound cavalier, but it’s not entirely irrational. Not all actinic keratoses become cancerous. In fact, only about 3% to 5% evolve into more invasive lesions. Those that do progress are relatively slow-growing and do not spread to other parts of the body quickly. Overall, squamous cell skin cancers are rarely life-threatening, provided they are detected and treated in the early stages.
But most dermatologists do make a compelling case for treating actinic keratoses sooner rather than later. “You want to protect against invasive cancers,” says Dr. Han Lee, director of dermatologic surgery at the USC University Hospital.
Patients who have hundreds of them have a high risk of developing cancer. Someone with 100 lesions could easily develop three or more squamous cell cancers; someone with 200 lesions might conceivably develop upward of 10. “Unfortunately, you can’t tell which lesions are going to progress simply by looking at someone,” Lee says.
Delaying therapy can complicate treatment and require more aggressive interventions. Squamous cell cancers typically need to be surgically removed, which can cause scarring. Because they frequently develop on the face, the results can be disfiguring.
Treatment of actinic keratosis not only reduces cancer risk but produces immediate cosmetic benefits too. “These lesions are rough and scaly; they can actually bleed when they’re bumped,” says Dr. Robert Brodell, a dermatology professor at Northeastern Ohio Universities College of Medicine. “They’re bothersome to anyone who has them.”
Selecting the best treatment method depends on a variety of factors. Among the most important is the number of lesions. Someone with a few isolated actinic keratoses is probably best off having each of them simply frozen off using cryotherapy.
Cryotherapy doesn’t make sense for individuals with more extensive disease. A chemotherapeutic medication called 5-fluorouracil (5-FU) is most commonly used in these cases. 5-FU is applied directly on the skin and attacks the rapidly dividing cells of actinic keratoses.
The newest medication to be approved for the treatment of actinic keratosis -- imiquimod -- also works well on individuals with multiple lesions. Imiquimod cream, which is applied topically, stimulates the body’s immune system to recognize and destroy the abnormal keratotic cells.
The drug appears to offer longer-lasting results than other therapies. Because the sun damage that causes actinic keratoses can’t be undone, new lesions frequently crop up following therapy. The immune boost provided by imiquimod, however, seems to persist, preventing additional actinic keratoses and squamous cell cancers from developing.
There is a downside, however: Imiquimod does not work for everyone, particularly people with compromised immune systems. “Only about 70% of people respond to it,” Brodell says. “There are some patients who get no reaction whatsoever.”
To work, 5-FU and imiquimod must be used regularly for several weeks, with both treatments producing significant inflammation, redness and crusting of the skin. Some people have difficulty complying with the therapy for this length of time; others are unwilling or unable to tolerate the side effects. For them, photodynamic therapy is an option. The skin is treated with a medication that makes it more sensitive to light; exposure to an intense light then selectively kills the keratotic cells. Although quicker than other approaches, photodynamic therapy also tends to be more expensive.
Finally, people looking for the best cosmetic result can turn to procedures such as dermabrasion, chemical peels and laser therapy. They successfully treat actinic keratoses and offer the additional advantage of reducing fine lines and eliminating irregularities in pigmentation. These procedures are not usually covered by insurance.
Four skin cancers later, my father finally elected to try 5-fluorouracil. After two weeks of daily therapy, he looked worse than he had before treatment. A month later, however, his skin is smoother than it has been in years and, presumably, his risk of skin cancer is substantially lower.
Now, his primary goal is to prevent further sun damage to his skin. Although he can’t kick the sunbathing habit altogether, he doesn’t head for the chaise lounge until after 5 in the afternoon. Although pleased about the results of his treatment, he’s not thrilled about his new confinement. “It’s killing me to stay inside all day,” he says.
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Dr. Valerie Ulene is a board-certified specialist in preventive medicine practicing in Los Angeles. She can be reached at themd@att.net. The MD appears the first Monday of the month.
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The types of skin cancers
Basal cell carcinoma
* Accounts for more than 80% of all skin cancers in the United States.
* A slow-growing cancer that almost never metastasizes, or spreads, to other parts of the body.
* Develops on sun-exposed areas of the body, such as the face, ears, neck and the backs of the hands.
* Exposure to ultraviolet light increases risk.
* Treatments: surgical excision, liquid nitrogen freezing, topical chemotherapy.
Squamous cell carcinoma
* Makes up approximately 16% of skin cancers overall.
* Rarely metastasizes when caught early but the potential for spread exists.
* Develops on sun-exposed areas of the body, such as the face, ears, neck and the backs of the hands
* Roughly 40% arise from actinic keratoses.
* Exposure to ultraviolet light increases risk.
* Treatment: surgical excision, liquid nitrogen freezing, topical chemotherapy, immune therapy, photodynamic therapy.
Melanoma
* Accounts for roughly 4% of all skin cancers.
* More aggressive than basal and squamous cell carcinomas and once metastases occur, treatment effectiveness is poor.
* Can arise anywhere on the body but frequently seen on the back, buttocks, legs, scalp and neck. Between 20% and 40% arise from an atypical mole.
* Exposure to ultraviolet light increases risk; a family history of melanoma is also a risk factor.
* Treatment: surgical excision (may also require radiation and chemotherapy).
For more information about skin cancer and what to look for in a self-examination (specific signs and symptoms of skin cancer), go to www.skincarephysicians.com/skincancernet/index.html.
-- Valerie Ulene
