Researchers have observed for several years that people who have a history of using oral contraceptives are less likely to develop ovarian cancer.
A team from Roswell Park Comprehensive Cancer Center and the University at Buffalo analysed those connections more deeply, reporting for the first time that the protective benefit of oral contraceptives is most pronounced with the most aggressive and fatal subtypes of ovarian cancer.
The research team, led by Kirsten Moysich, PhD, MS, Distinguished Professor of Oncology in the Departments of Cancer Prevention and Control and Immunology at Roswell Park, evaluated data from the Ovarian Cancer Association Consortium (OCAC) to determine whether any associations existed between prediagnostic use of oral contraceptives and incidence of highly fatal ovarian cancer.
They looked at pooled data from 20 case-control studies involving 579 patients who died within 12 months of being diagnosed with ovarian cancer, matched to a control group of 2,279 patients who did not have ovarian cancer.
After adjusting for potential confounding factors including age and parity, or whether the patients had given birth, the results show that any history of using oral contraceptives was associated with a 46% reduction in the odds of death within 12 months of diagnosis.
Their work is believed to be the first large, multicentre study to investigate the association between oral contraceptive use and risk of highly fatal ovarian cancer.
“The longer the history of oral contraceptive use, the greater the protection we observed in terms of reduced chance of dying from aggressive ovarian cancer,” says first author Jennifer Mongiovi, a graduate student working with Dr. Moysich at Roswell Park and also a Cancer Epidemiology fellow in the department of Epidemiology and Environmental Health at the University at Buffalo.
“For every five years of use, we observed 32% lower odds of highly fatal disease, compared to 13% for all ovarian cancer as previously reported by other researchers. This association also varies by histological subtype, and was found most protective for highly fatal endometrioid ovarian cancers.”
“Our results provide strong evidence that this is an area worthy of further study so that we can better understand the mechanisms behind this association and identify specific groups of people who may benefit most from this chemopreventive strategy,” notes Dr. Moysich.