Q. I was very interested in your article on aspirin and cancer. You commented that aspirin may help prevent cancer, but I can’t take aspirin, even in low doses. I use Tylenol for pain and fever — can it also help against cancer?
A. The aspirin story is encouraging, but it’s a work in progress. Current evidence suggests that daily low-dose aspirin, such as 81 milligrams, may help reduce the risk of certain malignancies. The evidence is best for gastrointestinal cancers, including colon cancer, but research also offers hope that aspirin may help protect against other tumors, including prostate cancer. However, aspirin can produce gastrointestinal bleeding and other side effects, even in low doses. All in all, most experts think it’s too early to recommend aspirin specifically for cancer prevention, except, perhaps, for some people who are at high risk for colon cancer and low risk of peptic ulcers and bleeding.
Aspirin is the oldest member of a large group of nonsteroidal anti-inflammatory drugs (NSAIDs). Aspirin is also the safest of these drugs, since it’s the only member of the group that does not increase the risk of heart attack and stroke. And a meta-analysis of 17 studies of aspirin linked the drug to a 17% reduction in the risk of prostate cancer. Other research suggests that various nonaspirin NSAIDs are also capable of reducing the risk of cancer. Twelve studies of nonaspirin NSAIDs reported a 10% reduction in the risk of prostate cancer.
Acetaminophen (Tylenol and other brands) is not an NSAID, but has activity against pain and fever that is quite comparable to aspirin and other NSAIDs. Acetaminophen is safer than NSAIDs; it does not cause bleeding or boost the risk of heart attack and stroke, but in excessive doses it can damage the liver, and a report linked regular use to hypertension, which is also a possible side effect of NSAIDs. But acetaminophen has little, if any, of the anti-inflammatory action that may help protect against cancer — so can the drug reduce the risk of malignancy?
Another report suggests it may be protective, at least against prostate cancer. The subjects were 78,485 men who volunteered to participate in the Cancer Prevention Study II Nutrition Cohort. The men were free of prostate cancer when they enrolled in the study in 1992. Each man provided detailed information on his medication and on demographic, medical, and lifestyle factors. The researchers tracked the men through 2007; during the 15 years of follow-up, 8,092 men were diagnosed with prostate cancer. Although previous, short-term, or low-dose use of acetaminophen was not linked to a reduced risk of prostate cancer, current regular use of 30 or more pills a month for five or more years appeared to reduce the risk of prostate cancer by 38% — and it also was linked to a 51% reduction in aggressive prostate cancer. These results remained valid even after the researchers took NSAID use, obesity, age, race, education, diabetes, and the frequency of PSA (prostate-specific antigen) testing into account.
Should you take acetaminophen for prostate cancer protection? No — or, at least, not yet. More research is needed; although an earlier study from the United Kingdom linked long-term acetaminophen use to a 40% reduction in prostate cancer, four smaller studies reported no benefit. And even though the new American study suggested substantial benefit, this type of observational study can establish associations but not cause and effect. Even so, as we await more research, the new study may help take the edge off aspirin envy among acetaminophen users.
— Harvey B. Simon, M.D.
Editor, Harvard Men’s Health Watch