Study finds breast-cancer hot spot in Southeast Missouri

Race and place matter when it comes to breast cancer survival rates, according to a study published last month, which identified clusters of so-called breast cancer hot spots in the United States.

Justin Xavier Moore, lead researcher on the study and cancer epidemiologist at Washington University in St. Louis, said there are two major clusters of these hot spots: one in Virginia and the Carolinas, and the other along the Mississippi River basin, beginning in Southeast Missouri and stretching into Louisiana � specifically in Southeast Missouri: Livingston, New Madrid, Osage, Saline, Scott and Stoddard counties, he said.

He gathered 15 years� worth of data from the Centers for Disease Control and Prevention�s records, grouped by county, because that was the smallest grouping available, he said.

The study, �Mapping hot spots of breast cancer mortality in the United States: place matters for Blacks and Hispanics,� appeared in international journal Cancer Causes & Control�s June issue.

To determine whether a particular county was a hot spot, Moore said, he looked at its rate of breast-cancer cases versus its population count, and whether that result indicated a high-risk area, he�d check to see whether adjacent counties were also high-risk.

He also compared these results against the United States� overall averages, he said, so as to minimize false positives and ensure he was being conservative.

Using those metrics, if a county was considered high risk, it was deemed a hot spot.

�This is a very stringent process,� he said of his research methods. �I wanted to be more conservative than less.�

Moore�s primary career focus is on breast cancer. He called it a �huge problem� in the United States in terms of mortality for women.

As many as 44,000 women per year die from breast cancer, he said, adding it�s the second leading cause of death outside cardiovascular disease among women.

It�s encouraging, he said, that in the last 30 to 40 years, breast cancer survivorship has improved overall, to about 90 percent after five years, but �the problem is, we�re seeing, even though survivorship is getting better, the problem still falls on a racial divide.�

Non-Hispanic white women have a survivorship rate of about 90 percent after five years, Moore said, but among African-American, Hispanic or Latina women, that number drops by more than 10 percentage points to just 79 percent.

African-American women are shown to be more susceptible to a particular type of breast cancer that isn�t as receptive to chemotherapy or radiation therapy, so that is an underlying physiological problem, he said. But he said that doesn�t account for the entire difference.

�One overarching theme is a connection between race, space and place, and cancer outcomes,� Moore said.

Socioeconomic problems can prevent people being able to afford regular visits to doctors, Moore said, so early detection would be less likely to occur.

People might also not be able to afford health insurance, he noted.

Lack of access to health care is another concern, especially in rural areas where clinics � and oncologists � might be far from where people live, he said.

Moore said his analysis of the CDC�s data was a bit more novel than standard cancer rate calculations, which would be found by dividing cancer mortality by the total death rate.

�I took into account geographic correlation,� he said.

He also gathered county health rankings � survey results noting whether a county had high percentages of residents who were obese, smokers, physically inactive, and so on.

He factored all of that in, stratified by race, he said.

�We saw some of the same trends, overall,� he said, and noted a lot of the counties were rural. �Put those factors together, and some of the things we already knew and were seeing before, were reaffirmed. Getting better measures of these factors is the next step.�

Moore said he did not take into account possible environmental factors, such as regular exposure to carcinogens such as might be found in farm chemicals, �mainly because the literature hasn�t deemed a lot of chemicals to be causally related.�

He said, early in his research, he did look into whether pollution might be related, but found no correlation.

Moore warned this data is, in a sense, ecological rather than personal. Since the data was gathered at a county level, not an individual level, causes can�t necessarily be identified, but factors can be shown to be present with these high rates of breast cancer, he said.

�The idea behind this study was to be a starting point to look at some of the possible reasons to highlight and focus on areas where we can possibly mitigate the burden and open up further research,� Moore added.

mniederkorn@semissourian.com

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