Aspirin may combat cancer, study suggests
Could the humble aspirin prevent breast cancer survivors from suffering a second bout of the disease or even dying from it? It is a strategy worth further consideration, suggests a provocative Boston study published yesterday.
Scientists from several Harvard-affiliated institutions reported that women who took aspirin after completing breast cancer treatment were half as likely to die from the disease as women who did not regularly use aspirin. Taking the centuries-old remedy also appeared to significantly reduce prospects that breast cancer would return, according to the study published online by the Journal of Clinical Oncology.
The study’s authors, along with cancer specialists not involved in the research, cautioned that while the findings are promising, they are not definitive and do not mean breast cancer survivors should start taking aspirin. The study’s conclusions were derived from comprehensive health surveys that registered nurses completed every two years, a form of research that can yield important hints about what works and what doesn’t in medicine but can’t provide absolute answers.
Still, the research adds to a growing mound of evidence that certain low-cost, tried-and-true medicines - aspirin and diuretics, for example - need to be regarded with more respect by doctors and patients who gravitate toward the newest drugs in the medicine cabinet. Studies have suggested that long-term use of aspirin may reduce the likelihood of developing colon cancer.
“There’s an increasing interest in aspirin as a cancer preventative,’’ said Dr. Larry Norton, director of breast cancer services at Memorial Sloan-Kettering Cancer Center in New York. “The bottom line is this study is a tenable hypothesis. But I wouldn’t recommend based on it that people go out and buy aspirin.’’
Researchers, led by Dr. Michelle Holmes of Brigham and Women’s Hospital and Harvard, used survey results from the Nurses’ Health Study to examine the potential impact of aspirin on breast cancer recurrence and survival in 4,164 nurses diagnosed with the disease between 1976 and 2002. A total of 341 women in the study had died from breast cancer by 2006.
After taking into account other factors that might explain why some women lived longer, the researchers, whose work was underwritten by the National Institutes of Health, concluded that aspirin may have figured prominently in reducing breast cancer deaths, as well as the risk of cancer spread, among nurses who took the medication. And there was a suggestion that women who took the drug on more days of the week had the best chance of beating breast cancer.
The study did not ask women what dose of aspirin they were taking, nor why they were taking it. However, previous findings from the Nurses’ Health Study have shown that the top reason women in the study took aspirin was to prevent heart disease.
Scientists can’t say for sure why aspirin might forestall cancer’s return, but research in laboratories and in animals has found that the ancient drug acts like water dousing the embers of a simmering fire, quieting inflammatory processes that contribute to cancer’s spread. Other studies in humans have reached mixed conclusions about aspirin and whether it has cancer-fighting propensities.
“We don’t know exactly the mechanism, but there are a lot of hints out there that aspirin has anticancer effects,’’ Holmes said. “It is important to reexamine some of these old drugs and see if there can be additive effects on top of conventional treatments.’’
While the researchers’ report concentrated on aspirin, their findings also suggested other nonsteroidal anti-inflammatory drugs - among the top sellers are Advil and Motrin - may reduce breast cancer recurrence, although that effect was evident only in women who took those medicines 6 to 7 days a week. No link could be established between acetaminophen - commonly sold as Tylenol - and reduced breast cancer mortality.
Usually, patients in the midst of chemotherapy, radiation, and other cancer treatments are discouraged from taking aspirin because of concerns about drugs interacting in potentially dangerous ways. And even when women start taking aspirin after treatment, there are still risks, including stomach bleeding and other gastrointestinal complications, specialists stressed.
“Physicians may opt to use aspirin in a breast cancer survivor but that would be based on their own judgment of risks and benefits,’’ said Dr. Powel Brown, chairman of clinical cancer prevention at M.D. Anderson Cancer Center in Houston.
Gold-standard trials that involve randomly assigning some patients to take a drug while others get a dummy pill are designed to assess risks and benefits rigorously, and yesterday, several specialists called for such a review of aspirin and breast cancer.
“Studies like today’s generally shouldn’t change clinical practice, they shouldn’t lead to a change in women’s health decisions,’’ said Dr. Eric Winer, chief of women’s cancer at Dana-Farber Cancer Institute. “What they do provide is good evidence to move forward with a study asking whether this finding is real and how it should be used in clinical care.’’
The American Cancer Society took a measured stance toward the new study, with Laura Hilderley, chief medical officer of the New England division, suggesting women discuss the findings with their doctor before taking aspirin.
Hilderley also offered a sober assessment regarding further aspirin and breast cancer research. Pharmaceutical companies have little interest in research on a drug with no patent protection and low profit margins, meaning government agencies are left to pay for such studies.
“Sometimes,’’ she said, “something like this, because it’s not a brand-new discovery in chemotherapy, it takes a while before it gets picked up and funded in a clinical trial.’’
Stephen Smith can be reached at firstname.lastname@example.org.