When it comes to cancer survival, the United States is sharply divided by race. According to the Centers for Disease Control and Prevention, the cancer death rate for African-Americans is 25 percent higher than whites, and Hispanics and Latinos are more likely to be diagnosed with cancer at a late, and more dangerous, stage of the disease.

Kids aren’t exempt from those disparities either — black and Hispanic children are more likely to die of many childhood cancers than their white counterparts. So what explains the survival gap?

For epidemiologist Rebecca Kehm, the answer could lie not in a test tube or even a patient’s race, but in their place in society. In a paper published Monday in the journal Cancer, Kehm and her coauthors pinpoint socioeconomic status as a factor in childhood cancer survival.

Scientists have long looked for a biological basis for the different survival rates among races. Kehm knew that socioeconomic status — a measure of an individual’s social standing, including income, education, and occupation — affects adults’ chances of surviving cancer. Persistent racism and institutional bias means that black and non-white Hispanic people are much more likely to live in areas of concentrated poverty. Could this explain why their children are more likely to die of some cancers, too?

“We know that there are so economic differences that are closely tied to race ethnicity,” says Kehm. “I wanted to show that there are other factors at play than the genetic component.”

Kehm and researchers at the University of Minnesota looked at data on nearly 32,000 childhood cancer patients from the National Institutes of Health’s Surveillance, Epidemiology, and End Results Program (SEER), a database of cancer statistics compiled from 19 geographic areas throughout the United States. Each SEER entry offers a statistical snapshot of an individual patient, including their race and where they live. The patients were diagnosed between 2000 and 2012.

The researchers determined the poverty level in the cancer patients’ neighborhoods, using census tract data. Then, they ran a statistical analysis to determine how much living in a high-poverty neighborhood affected the children’s chance of surviving cancer.

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