Melanoma rates skyrocketing in young adults

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The risk of developing the most dangerous type of skin cancer is now more than six times higher among young adults than it was 40 years ago, and women may be especially vulnerable.

A new study shows the number of melanomas found among women under 40 years old increased by more than eightfold between the 1970s and 2000s. Cases of melanoma among men under 40 also increased by more than fourfold during the same time period.

"We anticipated we'd find rising rates, as other studies are suggesting, but we found an even higher incidence than the National Cancer Institute had reported ... and in particular, a dramatic rise in women in their 20s and 30s," says researcher Jerry Brewer, MD, a Mayo Clinic dermatologist, in a news release.

Researchers say women may be hardest hit by melanoma because they are more likely to participate in activities that increase the risk of melanoma, such as using tanning beds or suntanning.

They say the findings are alarming, considering the rates of many other types of cancers are declining.

Melanoma on the Rise

In the study, published in Mayo Clinic Proceedings, researchers looked at the number of melanomas diagnosed for the first time among people ages 18 to 39 from 1970 to 2009 in Olmsted County, Minn.

Overall, the results showed melanoma rates increased among men and women by more than sixfold during the study period.

The incidence of melanoma was eight times higher among young women and six times higher among young men in 2009 than in 1970.

Researchers say the dramatic rise in melanoma rates among the young is most likely due to increased use of tanning beds since 1970, as well as other unsafe exposures to ultraviolet light, such as severe sunburns in childhood.

While the study showed melanoma in young people is on the rise, researchers found deaths caused by this most deadly type of skin cancer actually declined in this group.

"People are now more aware of their skin and of the need to see a doctor when they see changes," says Brewer. "As a result, many cases may be caught before the cancer advances to a deep melanoma, which is harder to treat."

How to Prevent Melanoma

Researchers say the best way to reduce the risk of melanoma and other types of skin cancer is to limit exposure to ultraviolet radiation from tanning beds or the sun.

"A recent study reported that people who use indoor tanning beds frequently are 74% more likely to develop melanoma," says Brewer.

Other ways to protect your skin and reduce the risk of melanoma and other skin cancers include:

By Jennifer Warner

Reviewed by Louise Chang, MD

SOURCES: Reed, K. Mayo Clinic Proceedings, April 2012. News release, Mayo Clinic.American Cancer Society: "Melanoma Skin Cancer."

[audemus]

You would think that by now everyone would have gotten the message.

[DawnBabcockPapple]

Maybe we should stop slathering chemical based sunscreens with known carcinogens on our babies and children's skin every day, all day of the summer for their entire childhood.

[lfitts2]

So the above is like the advocates of people who don't want to wear helmets while driving motorcycles saying that helmets do not prevent head injuries...to whit I say nonsense.

Simple...sun exposure causes injury and therefore melanoma and non melanoma skin cancers. If you get chronic sun exposure...like old time farmers, you may not have an increased risk of melanoma, BUT you clearly have an increased risk of other skin cancers. If you only get intermittent high dose sun exposure with burns you then may markedly increase your risk of melanoma. Tanning beds and tanning clearly increase the risk of all skin cancers INCLUDING melanoma.

The rate of melanoma has gone up because of better screening but also because now we have had 60 years of 'sun worshiping'. If you don't want to believe it...then don't let the facts get in your way...key points...wear sunblock and reapply. Avoid large amounts of sun exposure.

[CLS88]

One of the most important facts you should know is that an epidemic of the disease has in fact broken out among indoor workers. These workers get three to nine times LESS solar UV exposure than outdoor workers get, yet only indoor workers have increasing rates of melanoma — and the rates have been increasing since before 1940.

There are two major factors that help explain this, and the first has to do with the type of UV exposure.

There are two primary types of UV rays from sunlight, the vitamin-D-producing UVB rays and the skin-damaging UVA light. Both UVA and UVB can cause tanning and burning, although UVB does so far more rapidly. UVA, however, penetrates your skin more deeply than UVB, and may be a much more important factor in photoaging, wrinkles and skin cancers.

A study in Medical Hypotheses suggested that indoor workers may have increased rates of melanoma because they're exposed to sunlight through windows, and only UVA light, unlike UVB, can pass through window glass. At the same time, these indoor workers are missing out on exposure to the beneficial UVB rays, and have lower levels of vitamin D.

Researchers wrote:

"We hypothesize that one factor involves indoor exposures to UVA (321-400nm) passing through windows, which can cause mutations and can break down vitamin D3 formed after outdoor UVB (290-320nm) exposure, and the other factor involves low levels of cutaneous vitamin D3.

After vitamin D3 forms, melanoma cells can convert it to the hormone, 1,25-dihydroxyvitamin D3, or calcitriol, which causes growth inhibition and apoptotic cell death in vitro and in vivo. We agree that intense, intermittent outdoor UV overexposures and sunburns initiate CMM [cutaneous malignant melanoma]; we now propose that increased UVA exposures and inadequately maintained cutaneous levels of vitamin D3 promotes CMM."

To put it simply, UVB appears to be protective against melanoma — or rather, the vitamin D your body produces in response to UVB radiation is protective.

[CLS88]

Melanoma Increases Due to Benign Disease, Not Sunlight

Diagnostic drift, according to the study, refers to a hefty increase in disease that is being fueled by non-cancerous lesions.

In fact, during the study period from 1991 to 2004, there were nearly 4,000 cases of melanoma included in the report, with an annual increase of 9.39 to 13.91 cases per 100,000 per year.

The researchers revealed that, rather than being fueled by increasing exposure to sunlight as is commonly suggested, the increased incidence was almost entirely due to minimal, stage 1 disease.

They noted:

"There was no change in the combined incidence of the other stages of the disease, and the overall mortality only increased from 2.16 to 2.54 cases per 100,000 per year ... We therefore conclude that the large increase in reported incidence is likely to be due to diagnostic drift, which classifies benign lesions as stage 1 melanoma."

In other words, people are being diagnosed with melanoma skin cancer even when they have only a minimal, non-cancerous lesion, and these diagnoses appear to be skewing disease rates significantly. Further, adding even more credence to the growing body of evidence showing sun exposure is not the primary cause of melanoma, the researchers noted that the distribution of the lesions reported did not correspond to the sites of lesions caused by sun exposure.

They concluded:

"These findings should lead to a reconsideration of the treatment of 'early' lesions, a search for better diagnostic methods to distinguish them from truly malignant melanomas, re-evaluation of the role of ultraviolet radiation and recommendations for protection from it, as well as the need for a new direction in the search for the cause of melanoma."

Is Lack of Sunlight a More Likely Culprit?
Despite all the bad press linking sun exposure to skin cancer, there's almost no evidence at all to support it. There is, however, plenty of evidence to the contrary. Over the years, several studies have confirmed that appropriate sun exposure actually helps prevent skin cancer. In fact, melanoma occurrence has been found to decrease with greater sun exposure, and can be increased by sunscreens.