Maybe it was the rise of self-tanner in the 2000s. Or the multiple state laws banning teenagers from using tanning beds until they’re of legal age. Or maybe it was that famous Chicago Tribune column — and follow-up hit song — that advised young people to “wear sunscreen.”

Whatever the case, new findings published in JAMA Dermatology show a “sustained, statistically and clinically significant downtrend” in melanoma rates in people under 30.

While it’s hard to point to a specific intervention that led to the near 25% drop over 10 years’ time, researchers at Fred Hutchinson Cancer Research Center and the University of Washington who conducted the study are calling it a big win for cancer prevention.

“We can only guess that it’s attributable to sunscreen use and can’t show a direct correlation, but it feels really good,” said Hutch epidemiologist Margaret Madeleine, MPH, PhD, a co-senior author of the study. “To me, this is a real victory, helping to keep people from getting a pretty terrible disease. We hope that the trend continues and that as these younger [people] age they will remain at lower risk of melanoma.”

Turning the tables on a deadly trend

Melanoma has become the fifth most common cancer in men and women. It accounts for about 1% of all skin cancers diagnosed in the U.S. but causes most skin cancer deaths. The American Cancer Society estimates 96,480 people will be diagnosed with melanoma this year in the U.S. and 7,230 people will die of the disease.

The risk for melanoma goes up as we age (average age at diagnosis is 65), but this type of skin cancer is also diagnosed in young adults, especially young women.

Caused by UV exposure (via the sun or tanning beds), melanoma is strongly linked to childhood sunburn. Public health programs that promote the use of sunscreen or other forms of sun protection have helped to decrease melanoma rates in other parts of the world, such as Australia which has a very high rate of skin cancers.

Researchers from the Hutch and UW decided to investigate melanoma rates in the U.S. after immunotherapy researcher Kelly Paulson, MD, then with Fred Hutch, stumbled onto some promising data.

“It was just one of those fortuitous moments in science where I pulled some data to use as a comparator for another project and was taken aback by the trend in melanoma,” said Paulson, who also treats patients with melanoma. Paulson went to Madeleine and physician-scientist Jennifer Gardner, MD, of Seattle Cancer Care Alliance and the University of Washington, and the study was launched.

Melanoma rates drop in people under 30

Led by Madeleine and Gardner, the team gleaned data from two large repositories of cancer patient data — the National Program of Cancer Registries, or NPCR, and the Surveillance Epidemiology and End Results registry, or SEER — to determine the annual rates of melanoma diagnoses in four age groups: children (age 0 to 9), adolescents (age 10 to 19), young adults (age 20 to 29) and adults (over 30).

All told, nearly a million cases of invasive melanoma were reported to the databases between 2001 and 2015.

The researchers calculated the annual percentage change in melanoma rates in each age group for the most recent decade. They found that between 2006 and 2015, melanoma rates decreased in teens and young adults of both genders. Rates in teenage boys dropped by 4.4%; teenage girls dipped by 5.4%. Young men and women’s rates were down 3.7% and 3.6%, respectively.

All told, the total number of U.S. adolescent and young adult reported cases decreased by 23.4%, a development the researchers called “a sharp downtrend in incidence.”

Was it the sunscreen?

“We can’t specifically answer what caused decreased melanoma rates in those under age 30,” said Paulson. “But sun protective behaviors have increased in the U.S. over the same time period. It’s likely that the decreased melanoma observed in young individuals is due in part to better protection against sunburn, whether through clothing, sunscreens or behavioral factors.”

Tanning: from revered to ‘ridiculous’

The analysis didn’t bring all good news. Melanoma rates continue to climb in those over 40, with an increase of 1.8% in both men and women over the same 10-year period.

“Boomers grew up without sunscreen,” Madeleine said. “And melanoma rates are still increasing in older folks. So, we’re not there yet — the public health job is not done. We have to keep on it and encourage campaigns to promote sun-safe messages.”

Ann Marie Howard Vollmar, a 50-year-old nurse from Atlanta, said she remembers slathering baby oil all over her skin when she was young, trying to get ever more tan. But as she got older, and more information became available about the risks of sun exposure, her attitude toward tanning completely changed.

As has that of many others, thanks to cancer prevention messages.

Madeleine said various measures taken over the last 10 years — state laws banning the use of tanning beds for minors, parents consistently using sunscreen on their children, people using more sun protection like hats and sunglasses and long sleeves — have definitely moved the needle on melanoma rates.

“I have educated my son on this his entire life,” Vollmar acknowledged. “I think he was the whitest boy on the beach this summer.”

And that’s just fine with him.

“I think tanning is ridiculous,” said Kyler Vollmar, a 21-year-old college student. “There are still people who are tan-crazed, but I think it’s died down a lot.”

Who is most at risk for melanoma?

Some melanomas aren’t caused by UV radiation exposure. Children 9 and younger, for instance, didn’t see a reduced rate in melanoma rates “most likely because their disease is genetic and not influenced by the sun,” Madeleine said.

But when you look at the next age groups, she said, you start to see the likely influence of the sun or of tanning.

“The melanoma rates for women are twice as high as men in that 20- to 29-year-old range,” she said. “We’re making the assumption that the reason men have lower incidence of melanoma in this group is that they’re less likely to be tanning.”

Paulson agreed that the rise was likely due to intentional sunbathing in women, but added young men are more at risk for scalp melanomas, due to shorter hairstyles and male pattern baldness.

Older men are also at high risk for the disease, possibly because they spend more time working outside.

“The message is there’s a cumulative sun exposure,” said Madeleine. “Roughly two-thirds of melanomas are caused by sun exposure in people who are susceptible. The more we can do to interrupt that in susceptible people, the more likely we are to see reductions in overall incidence in the next couple of generations.”

Prevention and new therapies

Even if you’re diagnosed with melanoma, there’s still some good news.

New immunotherapies and targeted therapies have made a big difference even in people with advanced disease, Paulson said, calling the progress “wonderful.”

“These treatments have been shown to both greatly extend survival in [people with] metastatic or stage 4 disease: The median survival is now several years,” she said. “They’ve helped prevent recurrence or relapse and increased the rate of surgical cure for stage 3 disease.”

What’s more, Paulson said “it’s never too late to start using sun-protective clothing, hats and sunscreen to reduce future melanoma risk later in life.”

All in all, the researchers are thrilled that another deadly cancer may be on the decline.

“The clinicians were excited by the data, the public health scientists were excited by the data,” said Madeleine. “We see this as a tremendous validation of the potential to reduce the risk of a very bad disease through public health messages.”

And the news might get better in days to come.

“If we keep following these younger people as they age, we may no longer see this increasing trend in melanoma with age, but in fact start to see a decrease,” she said. “That’s our hope. So stay tuned.”

Funding for this study was provided by the National Institutes of Health, the Fred Hutch Immunotherapy Integrated Research Center and the Society for Immunotherapy of Cancer SITC-Merck fellowship.

This article was originally published on November 13, 2019, by Hutch News. It is republished with permission.