Cancer Risk Lowered by Aspirin
A major study directed by Dr. John A. Baron of Dartmouth Medical School showed that a daily baby aspirin modestly reduced the risk of colon cancer by preventing the growth of ominous polyps.
The research was done on 1,121 otherwise healthy men and women in nine cities who had polyps removed during routine screening. They were randomly given aspirin or dummy pills.
During repeat screening three years later, the researchers found that 38 percent of those getting baby aspirin had new polyps, compared with 47 percent of people getting placeboes. However, little benefit was seen among those getting full-size aspirin. Their recurrence rate was 45 percent.
Scientists have long speculated that aspirin protects against colon cancer. This study was the first to put the idea to a rigorous test.
The objective of the experiment was to see if aspirin prevents a recurrence of polyps after the growths have been removed during routine colonoscopies. It found the 80-milligram baby aspirin size taken daily reduces this risk by 19 percent. It is the same dose taken by millions of people to prevent heart attacks.
Prior large population reviews had shown that regular aspirin users have only about half as much colon cancer as usual. The problem was that these studies did not prove that aspirin is responsible for the decrease in colon cancer. It could very well have been due to some other lifestyle habit. This study was undertaken to see if people given aspirin solely to prevent polyps truly have fewer of them.
Colon cancer is the second-leading cancer killer in the USA, responsible for 48,000 deaths annually.
Based on the results from this study, it is reasonable to assume that for patients who are at moderately elevated risk of colon cancer, aspirin can be of benefit. However, caution is advised on the use of aspirin. Aspirin can interfere with blood clotting and can cause bleeding and digestive ulcers.
Date: April 7, 2002