Colon cancer has undergone a major geographical shift over the last few decades.
It used to be that Americans living in Northeastern states — including New England, Pennsylvania and Ohio — were most likely to die from colon cancer. But now, as the death rate has fallen by half, largely due to widespread screening, just three regions remain plagued by high mortality rates, and they’re all in the South.
The largest region is the Mississippi River delta, which spans seven states from Illinois to Mississippi and Louisiana. There, colon cancer kills 40 percent more people than in the rest of the U.S. on average.
That’s according to findings by an American Cancer Society study released Wednesday and published in the journal Cancer Epidemiology, Biomarkers and Prevention. It’s the first study to identify where colon cancer “hotspots” remain, and it could help the Centers for Disease Control and Prevention identify where to focus funding for screening and prevention.
Besides the Mississippi River region, another colon cancer hotspot encompasses Appalachia, which includes eastern Kentucky, southern Ohio and the western part of West Virginia, where deaths are 18 percent higher than average. And deaths are 9 percent higher in the third hotspot, in southeastern Virginia and northern North Carolina.
All three areas — the Mississippi River and Appalachia areas in particular — are known for high rates of poverty, obesity and chronic disease, and have higher insured rates than the rest of the country.
“It all goes hand in hand,” said Rebecca Siegel, a director at the American Cancer Society and one of the study’s authors. “The poverty is higher and so it affects access to care, health literacy. These people have other priorities besides their health — they’re trying to figure out where their next meal is coming from.”
Mortality rates from colon cancer in the three regions have improved, but much more slowly than in the rest of the country, which has seen dramatic improvements. Colon cancer now kills 15 people out of every 100,000, compared with nearly 30 people out of every 100,000 in 1970.
Back then, it more often stuck and killed Americans living in the northeastern part of the country, where higher incomes led to more meat consumption and jobs requiring less physical exertion — factors that are both linked to colon cancer.
“People with the most active occupations had low colon cancer mortality,” said Graham Colditz, a public health professor at Washington University. “The office workers from New Jersey to New England who sat at desks all day those were the ones dying of colon cancer.”
The turning point came in the 1990s, when screening became widespread. As more Americans got screened for colon cancer, especially those living in the high-mortality, high-income regions, the mortality rate began to fall dramatically. And that has changed colon cancer’s epicenter in a relatively short amount of time.
“It’s sort of a reversal of the pattern 30 years ago,” Colditz said. “We’ve flipped everything in a pretty short period of time, which maybe points to how much impact we can have on colon cancer.”
