Does Aspirin Reduce the Risk of Cancer?

In addition to its known blood anticoagulant properties, aspirin might also help prevent cancer, according to an article published in the Jan. 1, 2011 issue of The Lancet. The authors of the study examined past data from the medical charts of over 25,000 patients in eight different studies who were taking aspirin to reduce their risk of a cardiovascular event. They found that daily doses of at least 75 mg of aspirin for at least five years reduced the overall death rate due to cancer by an astonishing 21%.

So should we all start popping aspirin? Not necessarily, says the Deputy Chief Medical Officer for the national office of the American Cancer Society in his blog post of Dec. 6. Although he finds no fault with the reported results as an interesting observation, he points out that the study was a retrospective (in the past) examination of cancer deaths in studies originally designed for other purposes – far better would be a randomized prospective (looking into the future) trial, in which both the risks and benefits of aspirin could be studied together. But such a study would take another 20 years! Who wants to wait that long?

It’s a quandary often faced in medicine – what to do when there’s tantalizing new information that seems to point in a certain direction, but no way to know for sure. No doubt, some of you will be tempted to start taking aspirin as a result of this new study. Before you do, consider carefully that taking aspirin may be a double-edged sword; risks associated with taking aspirin include (in some people) gastrointestinal bleeding and bleeding in the brain. Doctors don't generally recommend aspirin for cancer prevention in healthy persons.