The state’s melanoma rate rose 35 percent for men and 38 percent women between 2005 and 2009. (The year 2009 is the most recent one for which numbers are available). In 2009, some 1,460 Minnesota were diagnosed with melanoma — almost three times more than were diagnosed a decade earlier in 1988.
“That’s a huge increase,” said Michelle Strangis, cancer policy coordinator for the MDH, in a phone interview Wednesday.
“We knew the rates were rising,” she added, “so it did not surprise us. But it’s very concerning.”
Melanoma develops in cells that produce the pigment melanin (melanocytes). The cancer usually appears on the skin — often (but not always) as a mole that changes its appearance. In rare cases, it develops elsewhere where melanocytes are found, such as in the eyes, mouth and small intestine.
Most cases of melanoma (65 percent) are caused by exposure to ultraviolet light, either from the sun or from indoor tanning. Family history, genetics and environmental factors also play a role. The disease can develop in people of all skin colors, but it’s most common among Caucasians.
Melanoma is a difficult cancer to treat, particularly once it has spread to the lymph nodes. In 2009, some 61,646 Americans were diagnosed with melanoma, and 9,199 died from the disease, according to the Centers for Disease Control and Prevention. As in Minnesota, the national incidence of melanoma has been steadily rising in recent years.
Groups at particular risk
The MDH data revealed that the risk of being diagnosed with melanoma rose for both men and women in Minnesota, and in all age groups. But there were two groups for whom the increased risk was especially high: men over the age of 55 and women aged 20 to 49.
The increased rate among older men is probably due to years spent outdoors, either working or pursuing outdoor hobbies, said Strangis. Research suggests a somewhat different cause, however, for the increased risk among women: tanning.
Here’s a particularly troubling statistic: Melanoma is the most common cancer diagnosed among Minnesota women aged 20 to 34. Indeed, Minnesota women aged 20 to 44 are 1.5 to 3.5 times more likely to be diagnosed with melanoma than Minnesota men of the same age.
“It’s concerning that teenagers and college girls are still interested in tanning, and that there’s a belief that it increases their attractiveness,” Strangis said. Contrary to popular belief, a tan is not a sign of health, she stressed, but rather a sign of damaged skin.
Getting that message across, particularly to young women, has been challenging. “The literature indicates we’re going to see continued increases in women’s rates of melanoma because the population that has been tanning hasn’t reached the age where their incidence has peaked,” said Strangis.
No such thing as a ‘safe’ tan
Many people — young and old — believe that if they give themselves a “base” tan before going out in the sun, they lower their risk of cancer.
“That’s a myth,” said Strangis. “Base tanning is simply more exposure to ultraviolet light, which increases your risk for skin cancer.”
One other major myth is that indoor tanning is safer than outdoor tanning. It isn’t, said Strangis. In fact, a 2006 study found that for people who use indoor tanning booths before the age of 35, the risk of developing melanoma increases by 75 percent.
Reducing the risks
To reduce your risk of melanoma and other skin cancers, limit your exposure to ultraviolet light. Avoid tanning booths and sunlamps. When you’re outdoors, wear protective clothing, sunglasses and a broad-spectrum sunscreen (SPF of 30 or more). (A hat is good, but remember that baseball caps do not protect the neck or ears, where skin cancers commonly develop.)
Also, watch for abnormal moles or skin growths, and be sure to seek medical advice at the first sign of something unusual. If you have a family history of melanoma, schedule regular skin exams with a dermatologist.