Adolescent girls and young women living in wealthy communities were more likely to be diagnosed with melanoma, according to a new study of skin cancer cases in California.
The authors think that might be because wealthier women may be spending lots of time out in the sun - at home and on vacation - and frequenting tanning beds.
"It's frightening actually," Dr. Elizabeth Tanzi, a dermatologist at Johns Hopkins University School of Medicine in Baltimore who was not involved in the study, told Reuters Health.
"The message of practicing safe sun is just not getting through to the people that need to heed the warning," said Tanzi, who also heads the Washington Institute of Dermatologic Laser Surgery in Washington, D.C.
Melanoma is the most lethal form of skin cancer, killing almost 9,000 people in the U.S. last year, according to the National Cancer Institute. Exposure to ultraviolet (UV) light is known to increase the risk of melanoma.
Cases of melanoma have been rising in young white women in the United States in recent decades, more than doubling since the early 1970s.
In the current study, Dr. Christina Clarke of the Cancer Prevention Institute of California and her colleagues analyzed data from a registry of more than 3,800 melanoma cases in white California girls and women aged 15 to 39. They paired the cancer statistics with information from the U.S. census to determine the socioeconomic status of each of the women, based on household incomes and education levels in their neighborhoods.
Rates of melanoma were significantly higher in women in the highest socioeconomic categories according to the findings, which are published in the Archives of Dermatology.
In the wealthiest 20 percent of California neighborhoods, four or five out of 100,000 young white women were diagnosed with melanoma over the 5-year period from 1998 to 2002. For the poorest group, the rate was less than one in 100,000 over the same period.
Compared to data from a decade earlier (1988 to1992), rates of melanoma increased in white girls and young women as a whole - but the increases were most obvious in wealthier women.
Wealthy women weren't more likely to get melanoma just because they lived in the sunniest areas of California. When the authors calculated how much UV light women in different neighborhoods were exposed to, they found that the wealthiest women living in areas with lots of UV radiation were still diagnosed with melanoma almost 75 percent more often than the poorest women who lived in communities with the most UV radiation.
Clarke said that it also wasn't likely that wealthy girls would be diagnosed with melanoma more often just because they have better access to health care. Invasive melanoma, she told Reuters Health, "is going to get very serious very quickly" - it's not something a woman would live with for years while thinking she was healthy.
A combination of outdoor sun exposure and tanning beds were probably to blame for higher rates of melanoma in wealthier girls, Clarke said. Mid-winter trips to Mexico or Hawaii, for example, require money and can be dangerous after skin has been covered up for months, she said.
Clarke said that wealthy girls especially are surrounded by the message that being tanned all year round is cool - they even have Katy Perry singing about it. But the new findings, she said, "should really cause us to think, 'how cool is a tan if it puts lighter skinned women at risk of deadly cancer?'"
One solution, Clarke said, could be bans on tanning beds for young girls and more education for wealthy girls and women to try to make tanning "uncool."
"The thought is that 'well, it can't happen to me,'" Tanzi said. "It's the invincible nature of a teenager. Tanning is still seen as somewhat okay to do."
The message that needs to get across, Tanzi said, is that "no tan is safe."