| ||
| ||
| ||
 |
|
|
|||||||||||||||||||||||||||||||||||||||||||||
Can daily aspirin prevent colon cancer?Studies: Disease risk lowered, but deadly side effects remain
BOSTON (Reuters) -- Popping a daily aspirin may help prevent the development of colon cancer, the second leading cause of cancer deaths in the United States, researchers said Wednesday. But two studies published in the New England Journal of Medicine do not resolve the issue of whether aspirin can prevent colon tumors in everyone, or whether the benefits of taking aspirin are great enough to warrant risking the sometimes deadly side effects of internal bleeding and stroke. "Although aspirin may be of some benefit in preventing colorectal cancer, it cannot yet be recommended for this indication and is not a substitute for screening and surveillance," Dr. Thomas Imperiale of the Indiana University School of Medicine wrote in a commentary. The first study, of 635 volunteers who had won one battle against colorectal cancer, found that among those who took a 325-mg aspirin daily 36 percent fewer people developed new growths, sometimes known as polyps. And when polyps did appear in the colon, there tended to be fewer of them. The study was halted early because the results were so decisive. Polyps themselves are not cancerous, but some polyp cells can mutate into tumors. "It provides a new way to lower the risk of recurrence in patients who have had colon cancer," said Dr. Richard Schilsky of the University of Chicago, who worked on the study. The study did not look at actual cases of cancer because colon tumors can take a long time to develop. But the researchers believe that reducing the number of polyps will cut the risk of colorectal cancer. The larger study, led by Dr. John Baron of the Dartmouth-Hitchcock Medical Center in Lebanon, New Hampshire, involved patients who had had polyps removed but had not developed cancer. After about three years, the researchers found new polyps or cancer in 12.9 percent of the 372 of the patients who got placebo pills compared to 7.7 percent of the 377 people taking an 81-mg baby aspirin tablet daily. To the surprise of the researchers, the 372 people taking a full-sized aspirin tablet each day -- 325 mg -- did not have a statistically significant reduction in risk -- 10.7 percent of them developed polyps or tumors. "The difference in the two studies could be that we enrolled higher-risk patients, or it could simply be due to chance," the Schilsky team wrote in their report. Imperiale said aspirin, given its side effects, is not as effective as established screening methods, such as a colonoscopy, for preventing death from colon cancer. He said at least 471 people would have to take aspirin for at least five years to prevent one case of colorectal cancer, and 1,250 people would have to be on an aspirin regimen for at least 10 years to prevent one death from colorectal cancer. Meanwhile, for every person who is spared colon cancer there would be one person who suffered from major bleeding as a result of the aspirin therapy, and more people would suffer a stroke than be spared death from colorectal cancer, according to Imperiale. Colorectal cancer kills about 57,100 Americans each year. Copyright 2003 Reuters. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
|
|
|||||||||||||||||||||||||||||||||||||||||||||
|
|
