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By Judi Bailey
Learn more about identifying this disorder and helping clients who demonstrate its symptoms.
Fair-skinned people who yearn for a suntan -- even though they know it's hopeless and unhealthy -- may one day have cause for celebration.
Harvard scientists have discovered new information about how the skin tans or -- in the case of fair-skinned people -- stubbornly refuses to tan due to a genetic defect. Using a skin treatment, they have turned pale skin dark, while also protecting it from ultraviolet-induced.
"Darkening a person's skin may mimic the protective benefit seen in people who otherwise make a large amount of pigment," says researcher David E. Fisher, MD, PhD, director of the Melanoma Program at Dana Farber Cancer Institute in Boston. And that could translate into a reduction in the toll of the potentially deadly skin cancer melanoma, expected to be diagnosed this year in 62,000 people in the U.S. and to result in 8,000 deaths, according to American Cancer Society projections.
The study appears in the Sept. 21 edition of the journal Nature. Fisher cautions that the study was done only in animals. Using a topical cream instead of the sun's rays, Fisher's team was able to switch on the tanning mechanism in the skin cells of fair-skinned mice, turning them into olive-skinned animals. "This has not been demonstrated in people and there is a lot that needs to be proven before it's ready for even a first attempt in clinical subjects," Fisher says.
Even so, the study was called intriguing by Meenhard Herlyn, DVM, PhD, a tumor biologist at The Wistar Institute, a research center on the campus of the University of Pennsylvania. "What he clearly has shown is ... you can induce a pigmentation, tanning, and the purpose is that people who are very susceptible to skin cancer, including melanoma, can be protected."
By Kathleen Doheny, WebMD, September 20, 2006
Rates of eczema and hay fever in the United Kingdom appear to have stabilized, after charting a steady rise over recent decades.
However, the study also found that rates of systemic allergic reactions -- including the severe condition known as anaphylaxis -- have surged in the past 20 years.
The researchers analyzed data gathered from numerous sources: national surveys, primary care doctors, prescription and hospital admission records, and death records.
Over the past three decades, diagnoses of allergic rhinitis and eczema in children have tripled, but there appears to have been a recent decrease in the prevalence of symptoms. Hospital admissions for eczema have stabilized since 1995, the researchers found, while admissions for allergic rhinitis have decreased to about 40 percent of their 1990 levels.
Between 1971 and 1991, the number of consultations with family doctors about hay fever increased by 260 percent and by 150 percent for eczema. However, these rates have stabilized in the past 10 years, the study said.
Hospital admissions for anaphylaxis have soared by 700 percent, for food allergy by 500 percent, and for the skin allergy urticaria by 100 percent.
Prescriptions for all types of allergies have increased since 1991.
The researchers said that some of the trends could be related to changes in medical practice and care but could also be explained by changes in the sources of allergic disease.
The study was published in the current issue of Thorax.
HealthDay News, September 7, 2006
The Cosmetic, Toiletry, and Fragrance Association (CTFA) is requesting public comments by September 25, 2006, on a new Safety Evaluation Guideline addressing the topic of Skin Absorption.
The guideline describes in vitro test methods for evaluating skin absorption.
The CTFA Safety Evaluation Guidelines provide manufacturers with guidance regarding the use of preclinical and clinical safety testing as a means to substantiate the safety of both ingredients and finished cosmetic products. They are part of the CTFA Technical Guidelines series.
Each Guideline undergoes an extensive development and review process by CTFA technical committees and staff, as well as public review by CTFA member companies, nonmember companies, federal government agencies, and scientific professional societies.
An electronic copy of the draft guidelines is available from the CTFA Public Affairs Department by contacting Lisa Powers, (202) 446-0489 or email at firstname.lastname@example.org.
The FDA is seeking to ban over-the-counter sales of skin bleaching drug products.
The FDA cites the possible risk ofand skin discoloration from hydroquinone typically found in these products.
However, those cancer studies were done on rats, not people.
"The actual risk to humans from use of hydroquinone has yet to be fully determined," the FDA states in its proposal, published in the U.S. government's Federal Register.
The type of skin discoloration noted by the FDA is called exogenous ochronosis, a darkening of the skin. The FDA cites research linking the condition to hydroquinone use.
The FDA isn't proposing a ban on prescription skin bleaching drug products. But all such products would need to submit a new drug application for the FDA's review.
Not all skin lighteners contain hydroquinone. The FDA knows of 200 products containing hydroquinone in strengths from 0.4% to 5%, about two-thirds of which "appear to be marketed as OTC [over-the-counter] drugs," says the FDA.
The FDA is taking comments on its proposal until Dec. 27.
WebMD spoke with dermatologist Susan Taylor, MD, of Society Hill Dermatology in Philadelphia, and the Skin of Color Center in New York about the FDA's proposal.
"I feel that hydroquinones are safe and effective treatment for pigmentary disorders," Taylor says. "I feel comfortable recommending that my patients continue to use hydroquinones if they have a pigmentary disorder."
"I think the evidence is quite weak with the link between hydroquinones and cancer," Taylor tells WebMD.
"Data on rats and mice cannot necessarily be extrapolated to human data," she says.
"In Africa, people have used hyrdoquinones for long periods of time ... meaning years, 10, 20, 30, years ... and at high concentrations," Taylor says. "We've not seen a proliferation of various types of cancers reported from that population.
Exogenous ochronosis is rare in the U.S., Taylor notes.
"If you look at the case reports, it's probably less than 200," Taylor says. "So it's really not a significant problem here in the United States."
Millions of Users
Taylor points out that "many patients have disorders that are truly disfiguring and devastating. And these conditions can be improved significantly with hydroquinone products."
"It's important therapy and it's used by millions and millions of people," Taylor says.
She says hydroquinone products are primarily used to lighten dark areas of the skin due to conditions including injury,, , and sun damage.
"So there are real problems and this is a real solution," Taylor says. She adds that filing new drug applications can cost millions of dollars.
"My concern is that we could lose prescription products that we have," Taylor says. "That would have major consequences, I think."
"It's safe, effective; it's the gold standard, and I think our patients would benefit from continued use for these problems. I think those three points sum it up for me," Taylor says.
SOURCES: U.S. Government Printing Office, Federal Register, Aug. 29, 2006; vol 71: pp 51146-51155. Susan Taylor, MD, Society Hill Dermatology, Philadelphia, Skin of Color Center, New York.
By Miranda Hitti, WebMD, August 30, 2006
By Howard Murad, MD
Find out how spa professionals can combat cultural stress in today's society.
Unless it's continuously reapplied, sunscreen can actually attack the skin and leave it vulnerable to ultraviolet (UV) radiation, concludes a University of California, Riverside study.
The researchers found that, over time, molecules in sunscreen that block UV radiation can penetrate into the skin and leave the outer layer susceptible to UV, CBC News reported.
The study appears in an upcoming issue of the journal Free Radical Biology & Medicine.
"Sunscreens do an excellent job protecting against sunburn when used correctly," Kerry Hanson, a research scientist in the university's department of chemistry, said in a prepared statement.
"This means using a sunscreen with a high sun protection factor and applying it uniformly on the skin. Our data show, however, that if coverage at the skin surface is low, the UV filters in sunscreens that have penetrated into the epidermis can potentially do more harm than good," he said.
HealthNews Day, 8/29/06
Acid skin peel, laser resurfacing, and a chemotherapy cream all remove precancerous skin growths and slow-- but patients prefer the peel.
Precancerous growths, small areas of discrete roughness to the skin, come from too much sun, note VA researcher Basil M. Hantash, MD, PhD, and colleagues. Particularly when a person has a lot of them, they tend to become squamous cell carcinomas:.
Doctors often burn off these growths, called actinic keratoses, with liquid nitrogen. But there's evidence other ways of removing them work at least as well.
Also, the other techniques appear to do another very important thing: They slow the development of cancer.
Hantash, of Palo Alto, Calif., and colleagues compared three of these techniques in 24 men. The patients had an average age of 73; all but three had previously had skin cancers removed. Five similar patients served as an untreated comparison group.
Before treatment, the 24 men had dozens of precancerous facial growths.
The researchers treated the men with laser resurfacing, an acid skin peel, or a topical cream containing fluorouracil, a chemotherapy drug.
All treatments worked, reducing the number of precancerous skin growths by 83% (chemo cream), 89% (skin peel), and 92% (laser).
Preventing New Cancers
The treatments also seemed to slow the development of new skin cancers.
Left untreated, the patients would be expected to develop 1.7 new facial skin cancers a year.
That's pretty close to what happened in the untreated comparison group. But the treated patients had only 0.04 to 0.22 new skin cancers per year.
"In the ... acid peel arm, one cancer per 26.1 years would be expected, compared with 1 cancer per 6.79 and 4.77 years in the [laser] and [chemo cream] arms, respectively," Hantash and colleagues report.
The untreated comparison group, they calculated, had 1.57 new cancers per year: that is, one new cancer every eight months.
The patients who got the acid peel were much more compliant with treatment, and had fewer side effects than those treated with laser or chemo cream.
Hantash and colleagues note that repeated treatments may be needed. In any case, patients with precancerous facial growths must get careful follow-up care.
Because the study had several limitations -- including its small size, infrequent use of sunscreen, and a control group that was not randomly picked -- the researchers warn that their findings must be confirmed in larger studies.
Hantash and colleagues report their research in the August issue of the Archives of Dermatology.
By Daniel DeNoon, WebMD, 8/21/2006
Overexposure to the sun's harmful ultraviolet radiation (UVR) kills 60,000 people a year, but most of these deaths are almost entirely preventable through simple protective measures, according to the World Health Organization.
UVR causes sunburn, triggers cold sores and ages the skin, according to its report, the first to outline the global health burden of sun exposure. Simple measures, such as covering up when in the sun, could cut the deaths, the BBC reported on Thursday. "We all need some sun, but too much sun can be dangerous -- and even deadly," said Dr Maria Neira, Director for Public Health and the Environment at WHO.
Of the 60,000 deaths, 48,000 are caused by malignant melanomas and 12,000 by other skin cancers, the report found. Small amounts of UVR are needed for good health and play an essential role in the production of vitamin D by the skin.
HealthDay News, 6/27/2006
Simply asking patients to map their moles on a drawing of their back after a monthly skin self-exam is an easy, low-cost way of reducing melanoma deaths, researchers report.
Melanoma is the deadliest form of skin cancer. It has a 95 percent survival rate if it's detected early but only a 16 percent survival rate if it's detected after it has begun to spread.
One of the best methods of detecting melanoma and other skin cancers is for patients to conduct monthly skin self-exams. However, it can be difficult for patients to accurately examine their skin without a method of remembering the location and size of existing moles, the study noted.
"Most melanomas are discovered by patients. So, we looked for a way to improve the accuracy of skin self-exams. Conducting the skin self-exam with the help of a diagram showing the location of moles, scars and other marks on the skin can help a person more easily notice any changes or new lesions, which are important warning signs for melanoma," study co-author Dr. Martin A. Weinstock, of Veterans Affairs Medical Center in Providence, R.I., said in a prepared statement.
The study, published in the August issue of the Journal of the American Academy of Dermatology, included 88 people who were educated about skin cancer and skin self-examination. The researchers took digital photos of the patients' upper and lower backs and instructed the patients to perform a self-exam before their next visit.
The patients were randomly selected to receive either a blank piece of paper (46 patients) or a "mole-mapping diagram" (42 patients). Those who received the diagram were told to draw their moles on it before their return appointment.
Between the patients' initial and return visits, the researchers randomly altered the photographs of the patients' backs, adding the image of a lesion. On their return visit, the patients were asked to indicate any changes on their photos.
Of the patients who received the mole-mapping diagrams, more than half were able to identify the changes made to their photos.
"The results suggest that asking the participants to create a mole-mapping diagram may improve the accuracy of skin self-exam, particularly identifying a new lesion," Weinstock said.
HealthDay News, 7/20/06