Childhood cancer rates are the highest in the Northeast and lowest in the South, a new government cancer map shows.
Leukemia is more common in the western states, while rates of pediatric lymphoma and brain cancer are higher in the Northeast.
It's not clear why the differences exist and because pediatric cancer is so rare, there's not much of a message for patients or their parents. The team at the Centers for Disease Control and Prevention says the main value of the data is for making sure doctors, hospitals and the government are ready to watch out for and take care of kids with cancer.
"Variation in childhood cancer incidence might be related to differences in exposures to carcinogenic chemicals (e.g., air pollution, secondhand smoke, food, or drinking water) or radiation," the team led by CDC epidemiologist Dr. David Siegel, wrote in their report.
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Also, there might be genetic variations in different populations. Inherited genetics account for about 5 percent of all childhood cancer, the National Cancer Institute says.
"Third, the rates of certain cancer types might vary by race/ethnicity. For example, Hispanic children have the highest rate of the most common type of leukemia, pediatric acute lymphoblastic leukemia, and states with a higher proportion of Hispanics might have higher rates of acute lymphoblastic leukemia," the CDC team wrote.
It could be some areas simply have better systems for detecting and reporting cancer, the team added.
"Similar to the findings from this report, recent data detailing adult cancers also indicate that the highest cancer incidence rates are in the Northeast," the researchers wrote.
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About 15,000 children and teens, 19 and younger, are diagnosed with cancer each year in the U.S., about 10,000 cases in kids 14 and younger. But survival rates are high — above 80 percent.
Most cancers are probably caused by genetic mutations that are not inherited, but that happen after birth.
"In adults, these gene mutations reflect the cumulative effects of aging and long-term exposure to cancer-causing substances," the National Cancer Institute says.
No. 1 is tobacco. Alcohol and obesity are also common causes of cancer.
But these are not risk factors that children normally have.
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Lowest rates in the South
Studies have looked into pesticides, infectious agents and living near nuclear power plants or power lines, but results have been mixed, with no clear indication any of these factors cause much, if any, pediatric cancer.
Siegel's team measured pediatric cancer rates per million. The Northeast has a childhood cancer rate of 188 out of every 1 million children, while the lowest rates are in the South, at 168 cases of cancer per 1 million children.
New Hampshire had the highest pediatric cancer rate at 205 cases per million, while South Carolina and Mississippi had the lowest rates, at 149 per million.