Researchers from the Centers for Disease Control and Prevention (CDC) have found that survival among women with ovarian cancer is influenced by age of menarche and total number of lifetime ovulatory cycles.
Previous studies have indicated that the factors associated with a decreased risk of developing ovarian cancer include fewer lifetime ovulatory cycles, higher parity, oral contraceptive use, hysterectomy and tubal ligation, according to the researchers. But little is known about the influence of these factors on a patient's survival after a diagnosis of ovarian cancer, wrote epidemiologist Cheryl L. Robbins, PhD, and colleagues (Cancer Epidemiol Biomarkers Prev online, July 9, 2009).
The researchers sought to explore whether these reproductive factors influence ovarian cancer survival.
Dr. Robbins' group conducted a longitudinal analysis of 410 women, aged 20 to 54 years. All participants were previously enrolled in the 1980-1982 Cancer and Steroid Hormone (CASH) study as incident ovarian cancer cases.
After a follow up of about 17 years, 221 women died; findings showed that overall 15-year survival among the study population was 48%. Lifetime ovulatory cycle and age at menarche were two factors that played a key role in predicting death from ovarian cancer. Women with the most lifetime ovulatory cycles had poorer survival compared with those who had fewer lifetime ovulatory cycles. Dr. Robbins explained that the number of lifetime ovulatory cycles a woman has is affected by her use of oral contraceptives, pregnancy and breastfeeding.
Mary B. Daly, MD, PhD, director of the Personalized Cancer Risk Assessment Program at Fox Chase Cancer Center in Philadelphia, said the results raised several questions such as how the amount and/or duration of reproductive hormones affected the aggressiveness of the cancer or its resistance to treatment. Also, what mechanism drives that response, she asked. Dr. Daly said that "the significance of this paper is in suggesting new research directions, not in any immediate treatment changes."