Women who take aspirin daily might reduce their risk of ovarian cancer by 20%, according to a study.
However, further research is needed before clinical recommendations can be made, reported researchers with the National Cancer Institute, part of the National Institutes of Health.
More than 20,000 women in the U.S. will be diagnosed with ovarian cancer in 2014, according to estimates, and more than 14,000 will die from the disease. Early-stage ovarian cancer may be successfully treated. However, symptoms associated with this disease can mimic more common conditions, such as digestive and bladder disorders, which contributes to frequent delays in receiving a diagnosis. Late-stage ovarian cancer leaves women with limited treatment options and poor prognoses, making preventive strategies potentially important for controlling the disease.
Chronic or persistent inflammation has been shown to increase the risk of cancer and other diseases. Previous studies have suggested that the anti-inflammatory properties of aspirin and non-aspirin NSAIDs might reduce cancer risk overall. However, studies examining whether use of these agents may influence ovarian cancer risk have been largely inconclusive.
This study, published in the February issue of the Journal of the National Cancer Institute, was described as the largest to date to assess the relationship between these drugs and ovarian cancer risk.
Britton Trabert, PhD, and Nicolas Wentzensen, MD, PhD, of NCIs Division of Cancer Epidemiology and Genetics, and their colleagues analyzed data pooled from 12 large epidemiological studies to investigate whether women who used aspirin, non-aspirin NSAIDs or acetaminophen have a lower risk of ovarian cancer. These 12 studies (nine from the U.S.) were part of the Ovarian Cancer Association Consortium. The scientists evaluated the benefit of the drugs in nearly 8,000 women with ovarian cancer and close to 12,000 women who did not have the disease.
Among study participants who reported whether or not they used aspirin regularly, 18% used aspirin, 24% used non-aspirin NSAIDs and 16% used acetaminophen.
The researchers determined that participants who reported daily aspirin use had a 20% lower risk of ovarian cancer than those who used aspirin less than once per week. For non-aspirin NSAIDs, the picture was less clear: The scientists observed a 10% lower ovarian cancer risk among women who used NSAIDs at least once per week compared with those who used NSAIDs less frequently. However, this finding did not fall in a range that was statistically significant.
In contrast to the findings for aspirin and NSAIDs, use of acetaminophen was not associated with reduced ovarian cancer risk.
This study adds to a growing list of malignancies, such as colorectal and other cancers, that appear to be potentially preventable by aspirin usage, the researchers noted. Our study suggests that aspirin regimens, proven to protect against heart attack, may reduce the risk of ovarian cancer as well, Trabert said in a news release.
However intriguing our results are, they should not influence current clinical practice. Additional studies are needed to explore the delicate balance of risk-benefit for this potential chemopreventive agent, as well as studies to identify the mechanism by which aspirin may reduce ovarian cancer risk.
Adverse side effects of daily aspirin use include upper gastrointestinal bleeding and hemorrhagic stroke. Therefore, a daily aspirin regimen should be undertaken only with a physicians approval, the scientists cautioned.
Study abstract: http://jnci.oxfordjournals.org/content/106/2/djt431.abstract