Thursday, May 27, 2010

What is the Risk for Melanoma Skin Cancer in Tanning Beds and Direct Sun Exposure?

Tags: UVA melanoma exposure with sunscreens since 1980s, Flaws in Melanoma Studies,

About 50 million Americans use Tanning-Beds, but I doubt few use it as much as those in the light skin Minnesota study whose results are very similar to other Scandinavians. The flaw in this study is that they examined only those who got melanoma, not checking their vitamin D level which most data agree that it helps prevent skin cancers, light skin people, especially redheads are especially susceptible to skin cancers and melanoma such as the Irish and Scandinavians.

Since the poor inhabit mostly areas where sun exposure is the maximum, we would expect an epidemic of melanoma there. In fact those who get melanoma survive at a higher rate than those who are diagnosed late in the more wealthy North. Heavy sunscreen use correlates with melanoma in Australia than those who do not use sunscreens and only wear shirts and hats.

The poorest way to conduct science is to select only those who get melanoma and ignore the large numbers who did not get melanoma from tanning-bed use. So if we assume all the melanoma in the US results from tanning beds, we get about 0.14 percent of total tanning bed users who develop melanoma.

Note that in the (Premier) MD Anderson research, their results indicated that among their kinds of patients, UVA in tanning beds made no difference. In the Minnesota study, it seems that it does matter if the patient got only UVA verses UVA and UVB. UVA increased the risk 4.4 Times among their selection of melanoma patients who survived. But don't forget that the exposure involved 50 hours or ten years of tanning bed use or 5 hours each season. Lots of students use tanning beds here for Spring Break and exposure starts at about 2-5 minutes and they get three or four customers per hour. Very few of them looked tan to me!

I am not sure what recommendations I can give to you, but the safest approach is to use short 10-4 PM real sun exposures.

Wikipedia ... The sun emits ultraviolet radiation in the UVA, UVB, and UVC bands. The Earth's ozone layer blocks 98.7% of this UV radiation from penetrating through the atmosphere. 98.7% of the ultraviolet radiation that reaches the Earth's surface is UVA. (Some of the UVB and UVC radiation is responsible for the generation of the ozone layer.)
Ordinary glass is partially transparent to UVA but is opaque to shorter wavelengths while Silica or quartz glass, depending on quality, can be transparent even to vacuum UV wavelengths. Ordinary window glass passes about 90% of the light above 350 nm, but blocks over 90% of the light below 300 nm.[4][5][6] ... http://en.wikipedia.org/wiki/Ultraviolet
UVA 440-315 nm or the tanning ray and likely cause of melanoma. Wikipedia ... 98.7% of the ultraviolet radiation that reaches the Earth's surface is UVA . Partially penetrates glass such as in autos. Superb UVA blocking sunscreens were available in Europe and Canada, our FDA kept them out by not approving them under Bush until American companies caught up to produce mostly inferior protection. Bush approved the French product in November 2006. Most melanoma studies are flawed because Americans did not use UVA sunscreens so the great outdoors with UVB sunscreens were a lot worse than tanning salons!
UVB 315-280 nm The burning and vitamin D producing sun rays. Sunscreens blocked this vitamin D producing UV light from the sun which led to huge deficiencies in vitamin D. When I found that just 15 of sun exposure by Caucasians produced as much as 22,000 IU of vitamin D, I realized immediately that our body needs much more than most doctors knew. I noted in the 1980s that melanoma cases mushroomed in Australia (Irish) and Scandinavian countries when sunscreens with only UVB protection. I only used sunscreen only when absolutely necessary such as vacations in the tropics or watching tennis matches for extended periods. I kept wondering why research into this was not funded by government or Big Pharma to determine if the blocking of vitamin D production would hurt us. Only Big Pharma knew?

Jim Kawakami, May 27, 2010, http://jimboguy.blogspot.com

American Cancer Society ... What is melanoma skin cancer? Melanoma is a cancer that begins in the melanocytes -- the cells that produce the skin coloring or pigment known as melanin. Melanin helps protect the deeper layers of the skin from the harmful effects of the sun. (UVA)

Melanoma is almost always curable when it is detected in its early stages. Although melanoma accounts for only a small percentage of skin cancer, it is far more dangerous than other skin cancers and causes most skin cancer deaths.

How many people are affected by skin cancer? Skin cancer is the most common of all cancers. It accounts for nearly half of all cancers in the United States. More than 2 million cases of non-melanoma skin cancer are found in this country each year. The American Cancer Society estimates that about 68,720 new melanomas will be diagnosed in the United States during 2009.

Who survives skin cancer? For basal cell or squamous cell cancers, a cure is highly likely if detected and treated early. Melanoma, even though it can spread to other body parts quickly, is also highly curable if detected early and treated properly. The 5-year relative survival rate for patients with melanoma is 91%. For localized melanoma, the 5-year survival rate is 99%; survival rates for regional and distant stage diseases are 65% and 16% respectively. About 80% of melanomas are diagnosed at a localized stage.

How many people will die from skin cancer? The American Cancer Society estimates there will be about 11,590 deaths from skin cancer in 2009: 8,650 from melanoma and 2,940 from other skin cancers. ...


USNEWS.COM/HEALTH Steven Reinberg, Health Day Reporter http://health.usnews.com/health-news/family-health/cancer/articles/2010/05/27/tanning-beds-can-greatly-boost-melanoma-risk.html

... John Overstreet, spokesman for the Indoor Tanning Association, said that "the latest science is contradictory. A study out just two weeks ago from the M.D. Anderson Cancer Center found that UVA light does not cause melanoma." (Patients probably a lot darker than those in the Minnesota study below. Jim)

And, a number of other studies and experts also tout the cancer-fighting benefits of vitamin D, which is produced by the skin via moderate UV light exposure, he said.

"So clearly, lots of studies are reaching far different conclusions," Overstreet said. "These other findings may not be promoted to the media as actively as those who may have a specific agenda, but they show that science is still wrestling with this issue and there's certainly still more to learn. We welcome a more complete body of research that will allow us to advise our customers on how to achieve their goals without unnecessary risk of overexposure." ...


... "We found the risk of melanoma was 74 percent higher in persons who tanned indoors than in persons who had not," said lead researcher DeAnn Lazovich, an associate professor at the division of epidemiology and community health at the University of Minnesota.

"We also found that people who tanned indoors a lot were 2.5 to 3 times more likely to develop melanoma than people who had never tanned indoors," she added. In the context of the study, "a lot" of indoor tanning meant a total of at least 50 hours of tanning bed exposure, or more than 100 sessions, or at least 10 years of regular tanning bed use.

The report is published in the May 27 issue of Cancer Epidemiology, Biomarkers & Prevention.

For the study, Lazovich's team collected data on melanoma cases in Minnesota from 2004 through 2007. The researchers also conducted interviews and had patients complete questionnaires about indoor tanning, including the devices used, when the person began tanning and for how long.

The researchers found that among 1,167 people with melanoma, almost two-thirds (63 percent) had used tanning beds. Among those who used tanning beds, the risk for developing melanoma rose 74 percent, Lazovich's group found.

The risk for melanoma was significant whether the tanning beds used both UVA and UVB rays or UVA rays only. For beds using UVA rays, the risk of melanoma was increased 4.4-fold.

"What is remarkable about our results are that they are very consistent," Lazovich said. "We found these relationships whether we looked at it by age, by gender, by where the tumor was found or by how we measured how much people tanned or what kind of devices they used." ...


Dr. Allan Halpern, vice president of the Skin Cancer Foundation and chief of dermatology service at Memorial Sloan-Kettering Cancer Center in New York City, said that, "together with the recently published extended follow-up of a large Norwegian-Swedish cohort, these data strongly support the conclusions of the International Agency for Research on Cancer that artificial UV tanning devices are carcinogenic in humans." ...

Dr. Allan Halpern, vice president of the Skin Cancer Foundation and chief of dermatology service at Memorial Sloan-Kettering Cancer Center in New York City, said that, "together with the recently published extended follow-up of a large Norwegian-Swedish cohort, these data strongly support the conclusions of the International Agency for Research on Cancer that artificial UV tanning devices are carcinogenic in humans." ...

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