More data link longtime estrogen use with ovarian cancer
Wednesday, July 17th 2002, 12:00 am
By: News On 6
CHICAGO (AP) _ A week after breast cancer and heart attacks were strongly linked to hormone replacement therapy, government scientists reported finding that long-term estrogen use may increase the risk of ovarian cancer.
The new National Cancer Institute research involving 44,241 postmenopausal women found that those who used estrogen-only supplements for 10 to 19 years had an 80 percent higher risk of developing ovarian cancer than women who didn't use hormone treatments.
The results, which echo two recent studies, were published in Wednesday's Journal of the American Medical Association.
The risk increased with length of use; a threefold risk was found in women who used estrogen for 20 or more years.
Despite the increased risks, the researchers noted that ovarian cancer was very rare, occurring in 329 women during the 1979-1998 study.
The results are similar to findings in a large American Cancer Society study published a year ago in JAMA, but that research did not include information on hormone users after 1982.
In April, Swedish researchers linked ovarian cancer to estrogen-only as well as estrogen-progestin use.
The new study also looked at ovarian cancer risks in users of combined supplements but those results were inconclusive, said cancer institute researcher James V. Lacey Jr., the lead author.
The study came just a week after another government study in JAMA linked long-term use of combined supplements to heart attacks and breast cancer.
Those results halted part of the highly regarded Women's Health Initiative study, though the researchers are continuing to examine the health effects of estrogen-only use in postmenopausal women.
The cancer institute's ovarian cancer findings are based on data from telephone interviews and periodic questionnaires about hormone use and the development of ovarian cancer.
Most of the estrogen-only users had had hysterectomies; combined therapy has been recommended for women with intact wombs because estrogen alone can cause uterine cancer.
In a JAMA editorial, Dr. Kenneth Noller of Tufts University said that while such ``observational'' studies don't prove cause and effect, the ovarian cancer results ``should be worrisome enough for clinicians to consider carefully whether to suggest estrogen-only'' supplements.