Frequent aspirin use may reduce ovarian cancer risk despite genetic susceptibility

By Melanie Hinze

Frequent aspirin use appears to lower ovarian cancer risk, even in individuals with genetic susceptibility to ovarian cancer, new research published in JAMA Network Open has revealed.

The study authors conducted a pooled analysis of eight population-based case-control studies from the Ovarian Cancer Association Consortium (OCAC) to investigate whether the association between frequent aspirin use and ovarian cancer risk was modified by  a polygenic risk score (PGS) for nonmucinous ovarian cancer.

A total of 4476 patients with ovarian cancer (median age, 58 years) were enrolled between 1995 and 2009, along with 6659 control participants (median age, 57 years). Ovarian cancer histotypes were high-grade serous (58%), low-grade serous (3%), endometrioid (15%), clear cell (8%) and other or unknown epithelial (15%) cancer.

Frequent aspirin use – defined as daily or almost daily use for six months or longer – was reported by  13% of case patients and 15% of control participants.

The authors assessed genetic susceptibility to ovarian cancer using a PGS that was previously developed within 63 OCAC studies and validated in external populations.

The authors found that the 13% reduction in ovarian cancer risk associated with frequent aspirin use was not modified by the PGS. Consistent associations between frequent aspirin use and reduced risk of ovarian cancer were seen in those with a PGS both less than and greater than the median.

Professor Susan Ramus, study author and lead of the Molecular Oncology Group  at UNSW Sydney, said  ‘We developed the large international consortium – the Ovarian Cancer Association Consortium – to study large numbers of cases and controls, to be able to address questions about the role of genetics and lifestyle factors in ovarian cancer risk.’

She noted that about 20% of the individuals in this international study were from Australia.

‘The study confirmed that the use of aspirin was protective for ovarian cancer and showed that there  was no difference in the protection for women with different genetic risk,’ she told Medicine Today.

‘As a result of this study and others like it, aspirin use may possibly be used in the future to reduce the risk of ovarian cancer in women with an increased risk due to their genetic predisposition,’ she added.

JAMA Network Open 2023; 6(2): e230666; doi:10.1001/jamanetworkopen.2023.0666.