Cancer concern prompts estrogen warning, but benefits may surpass risk

By RANDOLPH SCHMID

Associated Press

WASHINGTON — While emphasizing the value of estrogen treatments for women, a government scientific advisory panel recommended Friday that the chemical be added to the nation’s list of cancer-causing agents. Maybe, one scientist said, this step might encourage doctors to talk with their patients about both the risks and the benefits.

"Physicians never discuss any of these risks when they are prescribing hormone therapy," Michelle Medinsky, a toxicologist from Durham, N.C., told the National Toxicology Program advisory committee. "They only discuss benefits. Listing might force it on the table.

"Is knowledge power or is ignorance bliss? Everyone has to make their own decision," she said.

The committee, while expressing concerns that associating estrogen with cancer would overshadow the hormone’s usefulness, nevertheless voted 8-1 to recommend the listing. There was no suggestion that estrogen use be restricted or banned.

The listing should not frighten women, said Susan Wysocki, a Washington, D.C., nurse-practitioner who was not a part of the panel.

"Women need to know how estrogen can be given safely," said Wysocki of the National Association of Nurse Practitioners in Women’s Health. "By all means, women should be talking to their physicians, so that they do not get frightened about something that they’re doing that is actually good for their health."

An estimated 16 million postmenopausal women take hormone therapy — estrogen or estrogen combined with progestin. The therapy can reduce symptoms of menopause such as hot flashes and vaginal dryness and reduce the risk of osteoporosis. Some studies have suggested it reduces the risk of heart disease.

Millions of other women use birth control pills. The amount of estrogen in those pills has dropped dramatically in recent years.

The advisory panel acted after looking at studies showing that estrogen is associated with an increase in endometrial cancer and, to a lesser extent, breast cancer.

Doctors already know about the cancer link. That’s the reason post-menopausal estrogen is given together with another hormone called progestin: The combination lowers the risk of endometrial cancer.

But panel member Sheila Zahm of the National Cancer Institute noted that NCI researchers — in a paper published in January — had found a slight increase in breast cancer in women treated with the estrogen-progestin combination.

Hiroshi Yamasaki of Kwansei Gakuin University in Japan told the panel he was "uneasy" with assigning estrogen to the cancer list, noting the hormone’s value also needs to be stressed.

The committee advises the NTP, a branch of the National Institutes of Health that every two years updates the federal list of proven and suspected cancer-causing substances. The next update is scheduled early in 2002.

Also on Friday, the panel voted unanimously to recommend adding wood dust to the cancer list. It has been associated with cancer of the nose and sinuses in workers in furniture factories and cabinetmaking shops.