Study Links Aspirin, Lower Breast Cancer Risk
An aspirin a day may keep more than just heart attacks, strokes and colorectal cancer at bay. It also may protect women against breast cancer, especially those who have gone through menopause.
Researchers from Columbia University in New York compared the use of pain relievers among 1,442 women with breast cancer and 1,420 healthy women. Overall, women who took aspirin daily (at least seven pills a week) were 28% less likely to develop breast cancer than those who didn’t. Once-a-week users were 20% less likely to develop the disease than nonusers.
In general, the protective effects were strongest among post-menopausal women.
The study also found that daily aspirin use reduced by 32% the incidence of tumors fueled by estrogen, which accounted for 70% to 75% of all breast cancers, said the study’s senior author, Dr. Alfred I. Neugut, a professor of medicine and epidemiology at Columbia. There was no protective effect for tumors that weren’t sensitive to hormones.
“If this bears out, we’ll be able to develop a safe and targeted drug which will precisely protect against breast cancer without giving us the side effects of the aspirin,” which include ulcers and gastrointestinal bleeding, Neugut said.
The study found that regular use of the nonsteroidal anti-inflammatory drug ibuprofen, sold under such brand names as Motrin and Advil, also reduced risk. But that finding was less reliable because fewer data were available, Neugut said. The authors found no protection from acetaminophen (Tylenol), a pain reliever lacking aspirin’s ability to block the production of the inflammation-promoting prostaglandins, which are hormone-like chemicals.
The study is published in today’s issue of the Journal of the American Medical Assn.
Aspirin, which is both anti-inflammatory and helps keep blood from clotting, is already used to help prevent heart attacks and strokes. It has also been shown to reduce the incidence of colon cancer. The study authors theorize that, in breast cancer, aspirin inhibits the production of prostaglandins and thereby reduces production of estrogen, which can stimulate breast tumor growth.
The findings, they say, suggest that aspirin might work well in combination with other medications prescribed to women with hormone-sensitive tumors, such as the aromatase inhibitors anastrozole (Arimidex) and letrozole (Femara).
In an accompanying editorial, Dr. Raymond N. DuBois of Vanderbilt University in Nashville said that despite emerging evidence supporting aspirin’s potential, it was too soon to recommend it for breast cancer prevention because doctors didn’t know the optimal dose or regimen.
Dr. Christy A. Russell, an oncologist at USC, agreed. “This is telling us that there are hints that this class of drugs can reduce your risk of ever developing breast cancer,” she said. “However, these studies are not strong enough to suggest all women should now begin nonsteroidal anti-inflammatories for that prevention.”
The study was sponsored by the National Cancer Institute and the National Institute of Environmental Health Sciences.
