Almost 20 percent of the people in low-income communities who die of colon cancer could have been saved with early screening. And those premature deaths take a toll on communities that can least bear it.

Lower-income communities in the United States face $6.4 billion in lost wages and productivity because of premature deaths due to colon cancer, according to researchers at the Centers for Disease Control and Prevention.

"It's tragic not only for the lives lost, but it's tragic for the communities," says Hannah Weir, a senior epidemiologist at CDC who led the study. "That's money that's not being diffused back into these already disadvantaged communities."

The researchers looked at colon cancer deaths from 2008 though 2012 for people between 50 and 74 years of age. They figured out the preventable deaths by comparing the death rates in high-income counties compared to those with lower incomes. The higher-income areas were defined as those in which at least 85 percent of the population had graduated from high school.

Colon cancer used to be more common in white people with higher incomes, but over the past few decades screening has reduced their risk to the point that African-Americans now have higher rates.

"We know that colorectal cancer screening saves lives, and we know that people in these communities are less likely to be screened for cancer, so it's detected at a later stage," Weir says. "They're more likely to die from cancer."

Screening options include fecal occult blood tests, which are not invasive, as well as sigmoidoscopy and colonoscopy.

The researchers came up with the $6.4 billion number by comparing the differences in potential years of life lost due to premature death: 194,927 years in lower-income communities compared to 128,812 in higher-income communities.

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