Indoor tanning and the risk of melanoma

Researchers at the University of Minnesota, in Minneapolis, report the risk.

And the tanning industry disputes the findings.

First, the details.

• Cases of invasive cutaneous melanoma in Minnesota between 2004 and 2007 at ages 25 to 59 were reviewed.
• The data were compared to a randomly selected age- and gender-matched healthy group.
• Everybody answered questionnaires and participated in telephone interviews including information on the use of indoor tanning, types of devices used, age of first tanning bed use, years of use, dose, duration, and indoor tanning-related burns.
• The findings were adjusted for known melanoma risk factors.

And, the results.

• Among 1,167 cases of melanoma and 1,101 controls, 63% and 52%, respectively, had tanned indoors.
• People who used indoor tanning devices had a 74% increased risk of developing melanoma compared with those who never tanned indoors.
  • Increased risk was strongly correlated with frequency of use, whether assessed by hours, years of use, or total numbers of sessions.
• For those in the highest categories of use — at least 50 hours, more than 100 sessions or at least 10 years — their risk for melanoma was 2.5 to 3 times higher than people who never used a tanning bed.
• Patients who used tanning beds were more likely to…
  • Report painful burns while tanning indoors
  • Experience a greater number of burns while using a tanning device
  • Experience painful sunburns at a time when they thought they were protected from the sun by indoor tanning
• The risk for melanoma was elevated no matter when users began tanning indoors
  • Highest for those who began tanning before age 18.
  • Those who began tanning from 18 to 24, 24 to 34, and 35 and older were also at increased risk.
• High-speed or high-pressure devices increased the risk for melanoma by about 3 to 4 times vs those who had never used an indoor tanning device.
• Melanoma risk was especially elevated among users of UVB-enhanced and primarily UVA-emitting devices.

The bottom line?

The authors concluded, “This study overcomes some of the limitations of earlier reports and provides strong support for the recent declaration by the International Agency for Research on Cancer (IARC) that tanning devices are carcinogenic in humans.”

The International Smart Tan Network counters with the following points.

• Those with the most sun exposure throughout their lives had a 15% lower risk of skin cancer vs those with less exposure, which was downplayed by the study’s authors.
• A 75% greater risk of contracting cancer means the overall chance to begin with was less than 0.03%.
• The researchers have a record of anti-indoor tanning activities.
• 18 of 22 previous studies show no statistically significant association.

Just focusing on the issue of cancer risk: Yes, the risk of melanoma even with tanning bed use is low. The question that users of these devices must confront is whether the benefits of a tan outweigh the small but measurable potentially catastrophic health risk they expose themselves to.

Melanoma is the most serious form of skin cancer. When recognized and treated early, it’s nearly 100% curable. If not, the cancer can spread to other parts of the body, where it becomes hard to treat and even fatal. More from the Skin Cancer Foundation is here.

10/1/10 21:36 JR