What if an aspirin a day could keep cancer away?
A growing body of scientific research suggests that aspirin can prevent some cancers of the digestive system, and maybe even breast and prostate, too.
In the latest study, published today in the journal Cancer Epidemiology, Biomarkers & Prevention, Yale University researchers found that patients from 30 hospitals across the state were less likely to develop pancreatic cancer if they took a small, daily dose of aspirin.
Researchers are stopping short of recommending aspirin as a broad cancer prevention tool, because of its possible side effects, including stomach pain and gastrointestinal bleeding.
“Aspirin is not a risk-free substance,” said Dr. Harvey Risch, a professor of Epidemiology at the Yale School of Public Health, who led the research.
But people who are already taking aspirin to prevent heart attacks or fight pain should feel good that they may be reducing their cancer risk, too, he said.
And those at extra risk for colon, esophageal, or pancreatic cancer – either because of a previous bout, family history or smoking habit – may want to talk to their doctor about whether a baby aspirin a day makes sense for them, said Dr. Andrew Chan, a gastroenterologist at Massachusetts General Hospital and associate professor of medicine at Harvard Medical School.
The same small dose – usually 81 mg a day – is often prescribed to prevent heart attacks, and researchers first discovered a connection when they noticed that people taking aspirin for heart disease did not develop as many cancers as would be expected.
A higher dose, usually taken for pain, also helps, but isn’t necessary and is more likely to bring side effects, Risch said. A lower dose may work, too, but doctors don’t yet know how low is enough or how long someone needs to take aspirin to see a cancer benefit.
Researchers aren’t entirely sure why aspirin reduces cancer risk, but presume that it helps by reducing inflammation. Other anti-inflammatory drugs like Tylenol did not show the same anti-cancer benefit in the Yale study, Risch said, probably because they work in slightly different ways.
The mounting evidence that aspirin can prevent some cancers is prompting researchers to look more carefully at who benefits from aspirin therapy, how much should be given and who can tolerate it, said Daniel W. Rosenberg, an investigator at the Center for Molecular Medicine at the University of Connecticut Health Center in Farmington.
The new study, he said, “adds fuel to speed that along.”
Rosenberg has been studying several thousand colon cancer patients at John Dempsey Hospital at UConn, and also found a connection between aspirin and cancer prevention.
The strongest evidence for aspirin is in colon cancer prevention, Chan said. There is substantial evidence of a benefit for esophageal and pancreatic cancer, and emerging data suggesting protection against breast and prostate cancer as well.
The Yale study, which took place from 2005 to 2009, suggested that taking aspirin cut the risk of pancreatic cancer in half, but Chan cautioned that it’s probably much less.
Risch said he is studying pancreatic cancer in patients across the state to get a better understanding of what factors may contribute to the nation’s fourth deadliest cancer – and therefore what might be done to prevent it. He’s also been looking at the role of the bacteria H. pylori, known to cause ulcers and gastric cancer, as well as smoking and alcohol use.
Prevention is a better approach than treatment or early detection for pancreatic cancer, he said, because detecting the disease a year or two earlier is unlikely to make much difference in lifespan.