AR-News: Study Reinforces Hormones' Link to Breast Cancer

Andrew Gach unclewolf at
Tue Jun 24 15:49:53 EDT 2003

The New York Times, June 24, 2003

One year after a major study linked postmenopausal hormone therapy to an
increased risk of breast cancer, new findings from the same study paint an
even more ominous picture of the hormones' role in the disease.

The new results pertain to a widely used type of hormone therapy that
combines estrogen and progestin; the most popular brand is Prempro, made by
Wyeth. The results do not apply to the use of estrogen alone.

In addition to stimulating the growth of breast cancer, the combined
hormones may also make tumors harder to detect, leading to dangerous delays
in diagnosis, researchers are to report on Wednesday in The Journal of the
American Medical Association.

Women on hormones are also more likely to have changes in their breast
tissue that lead to abnormal mammograms, and those problems can show up
quickly, during the first year of hormone use. Many of the abnormalities
turn out to be harmless, but they can be nerve-racking and even risky, since
they require further tests that may include biopsies. Of the three million
women in the United States who now take combined hormones, about 120,000 a
year may have abnormal mammograms solely because of hormone treatment, the
researchers said.

Because breast abnormalities can develop so soon after a woman starts taking
hormones, the new findings raise questions about the safety of even
short-term use, which is commonly recommended to treat severe hot flashes
and other menopausal symptoms.

A sharply worded editorial accompanying the report said it provided "further
compelling evidence against the use of combination estrogen plus progestin
hormone therapy."

The hormone combination is now approved in the United States for only two
uses: to treat menopausal symptoms and to prevent the bone-thinning disease
osteoporosis. Because the hormones have risks, women are advised to use the
lowest dose for the shortest time possible, and to consult their doctors
about safer ways to prevent osteoporosis.

Bad news has been piling up about hormones, which were once promoted as
every woman's key to lasting youth, health and femininity. Recent studies
have found that many of the expected benefits never materialized and,
indeed, that hormones raise the risk of several serious diseases, including
some they were supposed to prevent. The increased risks are small, but many
doctors say even a small risk is not worth taking if there is no benefit to
counterbalance it. And for hormone therapy, rigorous studies have demolished
many claims of benefit.

For example, a study published last month found that combined hormones
doubled the risk of Alzheimer's disease and other types of dementia in women
who began the treatment at age 65 or older. That result was an especially
hard blow, because many doctors and patients had hoped for the opposite
result, that hormone therapy would prevent dementia.

The latest findings on breast cancer are from the Women's Health Initiative,
a large federal study of the combination therapy that was stopped ahead of
schedule a year ago because the hormones caused a small but significant
increase in the risk of breast cancer. The study also found that hormones
increased the risks of heart attack and stroke, which they were once thought
to prevent. Hormones also increased the odds of blood clots.

The study included 16,000 women and is widely considered to be the most
reliable and scientifically rigorous of the many studies on hormone therapy,
because it is the largest experiment to compare women on hormones with a
group taking placebos.

The new report is based on a further analysis of the data from the Women's
Health Initiative. The first report last July found a 26 percent increase in
the risk of breast cancer, which translates into eight extra cases per
10,000 women. In other words, if 10,000 women take hormones, 41 will develop
breast cancer, as opposed to only 33 breast cancers in 10,000 women not on
hormones. The latest report found a similar small increase in risk, 24
percent after 5.6 years of follow-up.

What is new in the latest report is the finding that compared to women not
on hormones, those who take estrogen and progestin tend to develop tumors
that are found at a more advanced stage and are harder to cure.

Of the 8,506 women on hormones, 199 developed invasive breast cancers,
compared to 150 cases in the 8,102 women on placebos. In the women taking
hormones, 25.4 percent had cancers that had begun to spread either to nearby
tissue or distant parts of the body, compared with only 16 percent in the
placebo group.

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