Hormone Therapy Raises Ovarian Cancer Risk
Study Shows an Increase in Risk for Estrogen-Only or Estrogen-Plus-Progestin Therapy
"It's a well done study," says Andrew Li, MD, a gynecologic oncologist at Cedars-Sinai Medical Center, Los Angeles, who reviewed the study for WebMD. "Their findings are in line with what other people report," says Li, who is also an assistant clinical professor of obstetrics and gynecology at the University California Los Angeles' David Geffen School of Medicine.
Like most research, the study has limitations that may have affected the results, Li says, and the authors also acknowledge this. Among the limitations are that the researchers didn't adjust for age at menopause or use of birth control pills; birth control pill use and early natural menopause both reduce ovarian cancer risk.
The main contribution of the new study is to look at large numbers of women who took different types of hormone therapy and determine which type or types carry risk, says Shelley Tworoger, PhD, an assistant professor of medicine and epidemiology at the Harvard School of Medicine and School of Public Health, who has also published her research on hormone therapy and ovarian cancer risk. "The real contribution [of the new study] is that the combined regimen also increases the risk of ovarian cancer," she says. In her research, Tworoger found that estrogen-only therapy boosted risk and a suggestion of an increased risk with estrogen and progestin therapy.
The new research basically confirms what has been shown in previous studies, says Corrado Altomare, MD, senior director of global medical affairs for Wyeth Pharmaceuticals in Collegeville, Pa. "This finding doesn't really change what we know," he tells WebMD. "We actually have a warning in our label about ovarian cancer."
Wyeth's label summarizes the risks found for ovarian cancer with hormone use, using information from various studies.
The best advice for women? "If a woman has a special predisposition for ovarian cancer, she should consider not taking hormones," Morch says. Past users, she says, can be reassured that their risk declines to that of never users after being off the therapy for two years.
Even with the link to ovarian cancer, Morch says, she is not saying hormone therapy should never be used. "Hormones may still have a therapeutic place in women with severe perimenopausal symptoms, and among women going into premature menopause," she says.
Women should talk to their doctor about hormone use, Li says, so the decision can be based on individual risk factors and medical history.