Daily or near daily aspirin use reduced the risk for nonmucinous ovarian cancer across most strata of genetic risk based on a polygenic score, according to a case-control study published in JAMA Network Open.

“While aspirin is a promising chemopreventive agent for ovarian cancer, its use remains limited by several factors. First, serious adverse events can occur with aspirin use, including gastric ulcer and hemorrhagic stroke; although rare, these risks are nonnegligible. Second, the incidence of ovarian cancer in the general population is low; thus, the number needed to treat to prevent one case of ovarian cancer is high,” Lauren M. Hurwitz, PhD, MHS, postdoctoral fellow in thedivision of cancer epidemiology and genetics at the National Cancer Institute, and colleagues wrote. “Targeting chemoprevention programs to individuals at higher risk of ovarian cancer could reduce the number needed to treat and improve the benefit-harm profile.”

Researchers pooled individual-level data from eight population-based case-control studies from the Ovarian Cancer Association Consortium in the U.S., U.K. and Australia between 1995 and 2009. In total, 4,476 patients with nonmucinous ovarian cancer (median age, 58 years) and 6,659 control participants (median age, 57 years) with both genetic data and frequent aspirin use data were included.

The primary outcome was nonmucinous epithelial ovarian cancer with frequent aspirin use defined as daily or almost daily use for 6 months or more.

Overall, frequent aspirin use was reported among 13% of patients with ovarian cancer and 15% of control participants. Polygenic score did not modify the 13% reduction in risk for ovarian cancer associated with frequent aspirin use (OR = 0.87; 95% CI, 0.76-0.99).

Researchers observed similar associations between frequent aspirin use and ovarian cancer risk among those with a polygenic score less than (OR = 0.85; 95% CI, 0.7-1.02) and greater than the median (OR = 0.86; 95% CI, 0.74-1.01) with results similar by histotype.

According to the researchers, these results are consistent with previous analyses including mucinous ovarian cancer cases.

“This work expands on the evidence base to suggest that chemoprevention programs could target individuals at higher risk of ovarian cancer, as defined by epidemiologic risk factors, polygenic risk, or both, to improve the benefit-harm profile of frequent aspirin use for ovarian cancer prevention,” the researchers wrote.