Will an Aspirin a Day Keep Ovarian Cancer Away?

Women who take aspirin daily may reduce their risk of ovarian cancer by 20%, according to a study by scientists at the National Cancer Institute (NCI), part of the National Institutes of Health. Before clinical recommendations can be made, however, additional study is needed.

Because the symptoms of ovarian cancer often mimic those of other common conditions, such as digestive and bladder disorders, ovarian cancer is often not diagnosed until it is in advanced stages. Treatment of late-stage ovarian cancer is limited and the prognosis is poor. Because of this, any strategy with potential to prevent the disease should be considered.

Chronic or persistent inflammation has been shown to increase the risk of cancer and other diseases, according to the study authors. Previous studies have suggested that the anti-inflammatory properties of aspirin and non-aspirin NSAIDs, may reduce cancer risk overall. However, studies examining whether use of these agents may influence ovarian cancer risk have been largely inconclusive. It was with preventive strategies in mind that this largest study to date assessed the relationship between these drugs and ovarian cancer risk.

Britton Trabert, PhD, and Nicolas Wentzensen, MD, PhD, of NCI’s 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, 9 of which were from the United States, were part of the Ovarian Cancer Association Consortium. The scientists evaluated the benefit of these 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 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, which include a wide variety of drugs, 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 significant statistically.

In contrast to the findings for aspirin and NSAIDs, use of acetaminophen, which is not an anti-inflammatory agent, 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 reported.

“Our study suggests that aspirin regimens, proven to protect against heart attack, may reduce the risk of ovarian cancer as well. 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,” said Trabert in a press release.

Adverse side effects of daily aspirin use include upper GI tract bleeding and hemorrhagic stroke. Therefore, a daily aspirin regimen should only be undertaken with a doctor’s approval, caution the scientists.

References:

Trabert B, Ness RB, Lo-Ciganic WH, et al, for the Ovarian Cancer Association Consortium. Aspirin, nonaspirin nonsteroidal anti-inflammatory drug, and acetaminophen use and risk of invasive epithelial ovarian cancer: a pooled analysis in the Ovarian Cancer Association Consortium. J Natl Cancer Inst. 2014;106:djt431. doi: 10.1093/jnci/djt431.