Aspirin, already widely used by people hoping to ward off a heart attack, may also be helpful in preventing pancreatic cancer.
In recent years reports of the benefits of aspirin have increased, including modest reductions in the polyps that can lead to colon cancer.
Now, University of Minnesota researchers report an apparent association between taking aspirin and reducing rates of often-deadly pancreatic cancer by as much as 43 percent.
Their findings are reported in Wednesday's issue of the Journal of the National Cancer Institute.
"This is an intriguing study, more along the lines of hypothesis generating as opposed to testing," said Dr. Ernest Hawk of the National Cancer Institute, who was not part of the research group.
"I think that aspirin may very well have this sort of activity but I wouldn't consider it definitive that this point," he said. "They will have to work out the risks and benefits."
Hawk noted that this was an observational study, not a randomized, controlled trial.
"It provides information that needs to be tested in a controlled study," he said. There have been prior studies of pancreatic cancer that didn't see any statistical effect in aspirin use, Hawk added.
Because aspirin can also have side effects, he said that people may not want to run out and start taking it just on the basis of this study, but added that "researchers may want to run out and do (more) studies."
The research team, led by Kristin E. Anderson and Dr. Aaron R. Folsom, studied the use of aspirin and other nonsteroidal anti-inflammatory drugs by 28,283 postmenopausal women who responded to health questionnaires in the Iowa Women's Health Study from 1992 to 1999.
Women who took aspirin had a 43 percent lower rate of pancreatic cancer than nonusers and the risk of the cancer declined with increasing frequency of aspirin use, the team reported.
Of 80 cases of pancreatic cancer found in the study, 33 were women who never used aspirin and 27 used it less than once a week. There were 10 cases among women who took aspirin two to five times a week and 10 among those using it six times or more weekly.
Risk factors for pancreatic cancer are not known and it is often rapidly fatal with few treatment options.