Minnesota has highest incidence rate of melanoma in Midwest

January 6, 2017
Sharon Marston


January 6, 2017: Despite increased efforts to raise public awareness about the prevention and early detection of melanoma, a growing proportion of Americans are both developing and dying from this aggressive form of skin cancer, according to a study published recently in JAMA Dermatology.

A second study, published in the same journal, reports that up-or-down trends in the incidence and death rates for melanoma vary among geographic regions and states, in part because of demographic differences.

The Midwest — including Minnesota — does not fare well in that study. It is cited as being among the 21 states that have experienced an increase in both melanoma incidence and death rates over the past decade.
Melanoma, which develops in the melanocytes, or cells that give skin its color, is considered the most serious form of skin cancer. When it’s found early and within the skin’s thin outer layer, or epidermis — a stage of the disease known as in situ melanoma — the cancer is treatable. But melanoma can spread quickly to deeper layers of the skin and then to other parts of the body, where it can become much more difficult to eradicate.

The cause of all melanomas isn’t clear, but most are believed to be the result of exposure to ultraviolet (UV) radiation from sunlight or tanning lamps and beds. Having fair skin, many (or unusual) moles, and a history of sunburn are among the factors that increase the risk of developing the disease.

Study #1
For the first study, a group of researchers led by Dr. Alex Glazer of the National Society for Cutaneous Medicine in Millwood, N.Y., compared 2016 melanoma data for the United States (collected from the American Cancer Society) with 2009 data, which they had reported on in 2010.

They found that the incidence rate for melanoma rose from 22.2 new cases per 100,000 people in 2009 to 23.6 new cases per 100,000 in 2016. In actual numbers, that meant that an estimated 76,380 Americans were diagnosed with the disease in 2016 compared with 68,480 in 2009.

The current lifetime risk of developing an invasive melanoma is now 1 in 54 — a jump from 1 in 58, they added. When combined with the more common in situ melanoma, the lifetime risk is now 1 in 28.

The incidence of in situ melanoma is increasing at a faster rate than that of the invasive form, a finding that may be an indication that early detection is having an impact. But as Glazer and his colleagues point out, the incidence of thicker, invasive melanomas is also rising — as is the disease’s mortality rate.

In 2016, an estimated 10,130 Americans will have died from melanoma, up 1.5 percent from the 8,650 who died from the disease in 2009.

“Despite the 2014 Surgeon General’s Call to Action to Prevent Skin Cancer, this study’s results demonstrate that the incidence of invasive melanoma in the United States is increasing on a lesser trajectory in the last 7 years than the mortality rate, suggesting that we may not yet be seeing the effect of earlier detection on melanoma mortality,” the researchers conclude.

Study #2
In the second study, Dr. Robert Dellavalle of the Denver Veterans Affairs Medical Center in Denver and his colleagues analyzed 2003-2013 melanoma state and regional data collected by the Centers for Disease Control and Prevention (CDC).

They found that of the 48 states that kept track of deaths from melanoma during that period (all except Alaska and North Dakota), 23 reported a lower death rate from the disease at the end of the 11 years, while 21 reported a higher rate. Four states experienced no change.

Of the 49 states that reported melanoma incidence rates during the period (all except Nevada), 11 experienced a decrease and 38 experienced an increase.

“Several US geographic regions may require special focus,” Dellavalle and his colleagues write. “Eight (73%) of 11 midwestern states (for which we had information) experienced a rise in both death and incidence rates between 2003 and 2013, perhaps indicating a greater number of melanoma cases resulting in a greater number of deaths.”

Minnesota was among those states. In fact, it had the highest melanoma incidence rate of any of the Midwestern states in 2013, the study reports.

On the other hand, the Northeast — specifically New England — experienced a reduction in both death and incidence rates. “Strong skin cancer prevention programs likely played a role in this region’s success,” the researchers write.

Not a surprise
The findings regarding Minnesota did not come as a surprise to officials at the Minnesota Department of Health (MDH), which provided the CDC with the state melanoma data used in the study.

“If anything, the numbers might be a little underestimated, but we don’t know yet,” said Michelle Strangis, an MDH cancer policy specialist, in an interview with MinnPost. The melanoma statistics for 2013 have not yet been officially finalized, she explained.

Why is Minnesota experiencing such a high incidence rate with this cancer? It has to do with demographics — specifically, with Minnesota’s large white population (85 percent of the state’s residents, according to the U.S. Census Bureau), who are at greatest risk of developing the disease.

White men over the age of 60 are particularly at risk, and Minnesota has a large number of people in that demographic, said Strangis. Many of those men were involved in farming or other outdoor activities that exposed them repeatedly to the sun — exposure that began decades ago, when there was less awareness of the need for protecting oneself from UV radiation, she added.

Minnesota’s high melanoma incidence rate may also be a reflection of the state’s health-care system, which tends to outperform those of many other states.

“Incidence is related to detection,” said Strangis. “And we have a very good health-care system in Minnesota, so we are probably detecting more skin cancers.”

Melanoma has a long latency period (the time between the UV exposure and the development of the cancer), but recent research has shown that the latency period may be shortening among younger people engaged in indoor tanning — a disturbing trend.

Strangis says she’s hopeful, however, that the state’s melanoma incidence rate will decrease in the years to come as more Minnesotans take steps to protect themselves from UV rays.

“The thing I’m really hoping that will happen is that we will have a different norm around beautiful skin,” she said. “We are still coming up against the idea that tan is beautiful rather than that tan is damaged skin.”

To protect against melanoma (and all forms of skin cancer), avoid direct sunlight as much as possible and use sunscreens and other forms of sun protection when outside.

“That’s the best prevention,” Strangis stressed.

FMI: You can find both studies on the JAMA Dermatology website, here and here. You’ll find information on how to prevent melanoma — and how to recognize its warning signs — on the American Cancer Society’s website. If you prefer your information in video format, Strangis recommends resources on the Colorado School of Public Health’s website.


Article Written By: Susan Perry

Link to Article:  MINNPOST