Rise in skin cancer rates reported.

Rise in skin cancer rates reported

New data show that more people than ever before are getting melanoma, the most serious form of skin cancer.

"The growth in the number of cases since 1980 has been 93 percent in the United States," says Darrell S. Rigel of the New York University Medical School in New York City. While some scientists believe the rise is a statistical artifact due to increased early diagnosis of the disease, Rigel's data indicate there are simply more melanoma cases -- and the problem is not restricted to the United States. "This rate of increase is roughly the same as the rate found in 21 studies in 16 other nations," Rigel notes.

Those blistering, peeling burns that beachgoers got from unprotected sun exposure in the 1960s nd 1970s may be part of the problem. Doctors believe melanoma is caused not by chronic sun exposure but by binge sunbathing. In the United States, a person who gets one blistering sunburn in his or her 20s is three times more likely to develop melanoma than one who has never had a bad burn, Rigel says.

Indeed, doctors report seeing younger and younger patients with melanoma. In the past the disease was rarely seen in patients younger than 40; now doctors are getting many patients in their 20s and 30s.

The trend could worsen if the ozone layer continues to be depleted, Rigel notes. the thin layer of ozone in the stratosphere protects Earth's inhabitants from damaging ultraviolet radiation present in natural sunlight. But increasing releases of chlorofluorocarbon compounds, chemicals used in refrigerators, apparently have damaged the ozone shield.

Melanoma is one of the most lethal forms of cancer, Rigel says, noting that it is almost always fatal if it spreads to other parts of the body. But doctors have a high success rate if they catch the disease early enough. "If you catch a melanoma early and remove it, it's 100 percent cured," Rigel says. He suggests patients use lots of sunscreen and see their doctor if they notice a speckled mole that has an irregular shape.

Another research team suggests the type of sunscreen used may be important. Elizabeth Knobler and her colleagues at Columbia Presbyterian Medical Center in New York City report that benzophenone, a chemical used in certain sunblock lotions, may cause an allergic reaction triggered by light. Knobler's group saw four patients who broke out into a rash after they had applied suntan lotion and were exposed to the sun. The problem can be dangerous, she says, because patients may think the rash is due solely to sun exposure and so may apply more suntan lotion. Consumers should test porducts on a small patch of skin to see if they react to the chemicals, Knobler suggests.