A National Cancer Institute (NCI) analysis published in February of 2014 did find that taking aspirin daily may lower a woman’s risk of ovarian cancer by as much as 20 percent. It is believed that aspirin, being an anti-inflammatory drug, may help by decreasing chronic or persistent inflammation that increases the risk of cancer and other diseases. Earlier studies have suggested that aspirin and other non-steroidal anti-inflammatory drugs (NSAIDS) may reduce cancer risk overall, but until now, studies looking at whether these drugs can lower the risk of ovarian cancer have been largely inconclusive, the NCI researchers said. This new analysis is the largest one to investigate whether NSAIDS can affect the risk of ovarian cancer specifically.
Every year, some 22,000 women in the United States are diagnosed with ovarian cancer and an estimated 15,000 women die as a result of the disease. In its early stages, ovarian cancer often causes no symptoms. Later, symptoms can mimic more common conditions, such as digestive and bladder disorders, and for these reason, it is often not diagnosed until it is advanced and less treatable.
The NCI researchers analyzed data from 12 large epidemiological studies to discover whether taking aspirin, non-aspirin NSAIDs, or acetaminophen (which is not an anti-inflammatory drug) results in a lower risk of ovarian cancer. The study team looked at data on 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.
They found that 18 percent of the women took aspirin regularly, 24 percent took NSAIDS and 16 percent took acetaminophen. The investigators were able to determine that women who reported taking aspirin daily had a 20 percent lower risk of ovarian cancer than those who took aspirin less than once a week. They also found that taking NSAIDS at least once a week appeared to lower the risk of ovarian cancer by 10 percent compared to women who took NSAIDs less often, but this benefit turned out not to be statistically significant. Predictably, taking acetaminophen was not associated with any reduction in risk.
We already know that taking daily, low-dose aspirin lowers the risk of colorectal cancer and other types of cancer, as well as heart attacks.
Because we don’t yet have a means of detecting ovarian cancer at its earliest and curable stages, finding a way to reliably lower the risk would be the next best thing. You should keep in mind, however, that taking aspirin can lead to serious side effects such as gastrointestinal bleeding and hemorrhagic stroke, so starting aspirin therapy as an anti-cancer strategy can have a downside. As with any therapy, there are risks and benefits that need to be considered.
The NCI researchers concluded that more research is needed before doctors can recommend that all women take aspirin to prevent ovarian cancer and if so, what dose would be best.
Andrew Weil, M.D.
Britten Trabert, et al. "Aspirin, non-aspirin NSAID, and acetaminophen use and risk of invasive epithelial ovarian cancer: a pooled analysis in the Ovarian Cancer Association Consortium", JNCI. February 6, 2014. DOI: 10.1093/jnci/djt431.