Women with the most lifetime ovulatory cycles had poorer survival compared with those who had fewer lifetime ovulatory cycles. Robbins explained that the number of lifetime ovulatory cycles a woman has is affected by her use of oral contraceptives, pregnancy and breastfeeding, all of which temporarily cause ovulation to cease and reduces the total number of cycles.
Furthermore, the researchers determined that those with the youngest age at menarche also had poorer survival. After diagnosis of ovarian cancer, participants whose menarche began before age 12 were more likely to die compared with those whose menarche began at age 14 or older.
"We now have evidence that higher numbers of lifetime ovulatory cycles may play a role in the development of ovarian cancer as well as the risk of death after being diagnosed with the disease," Robbins concluded.
This study points to some important future directions of research for better understanding the influence of reproductive factors on ovarian cancer survival.
Mary B. Daly, M.D., Ph.D., director of the Personalized Cancer Risk Assessment Program at the Fox Chase Cancer Center in Philadelphia, said these results raise the question "can the amount and/or duration of reproductive hormones to which women are exposed affect the aggressiveness of ovarian cancer and/or its resistance to treatment, and if so, by what mechanism?"
"The significance of this paper is in suggesting new research directions, not in any immediate treatment changes," said Daly, who is also an editorial board member for Cancer Epidemiology, Biomarkers & Prevention. "The next steps would be to study this association in a prospective study, then to characterize molecular and genetic profiles of ovarian tumors and compare these profiles among different levels of exposure to reproductive hormones."
There is a need for additional studies to ex
|Contact: Tara Yates|
American Association for Cancer Research