Their study, presented at the American Society of Clinical Oncology
meeting in Chicago, showed that women who received AstraZeneca PLC's
drug goserelin along with chemotherapy were 64 percent less likely
to develop premature menopause than women who had chemotherapy
alone. They were also more likely to have successful pregnancies,
and the treatment appeared to improve survival.
Early menopause is a common side effect for younger women undergoing
chemotherapy for hormone-receptor-negative breast cancer, a type of
cancer not driven by the hormone estrogen or progesterone.
About a quarter of breast cancers occur in women under 50, affecting
some 40,000 to 50,000 women each year. Unlike natural menopause,
which occurs gradually, chemotherapy can suddenly throw a woman into
full-blown menopause. In about half of these women, this condition
is permanent, eliminating the chance for a future pregnancy.
"This is the first time anything has been shown to prevent this,"
said Dr. Kathy Albain of Loyola University Medical Center, a senior
author of the study. "I think these findings are going to change our
Goserelin, whose brand name is Zoladex, closely resembles a hormone
normally released by the hypothalamus. It is already approved for
prostate and advanced breast cancers. In premenopausal women, the
drug temporarily shuts down the ovaries, essentially putting them on
hold during chemotherapy.
Out of 257 patients in the trial, half received chemotherapy alone
and half got chemotherapy plus monthly injections of goserelin.
After two years, 8 percent of women in the goserelin group had organ
failure versus 22 percent in the standard chemotherapy arm. Among
those getting goserelin, 22 women (21 percent) got pregnant compared
with 12 women (11 percent) receiving chemotherapy alone. Of these,
16 women in the goserelin group delivered at least one healthy baby
versus eight in the control group. Another three patients from the
goserelin group and two from the control group were still pregnant
when the data was collected.
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During the study's design, researchers were concerned that adding
the hormone treatment might hurt the women's breast cancer
But the results suggest women who got goserelin were 50 percent more
likely to be alive four years after starting treatment compared with
those receiving the standard therapy.
Goserelin is not currently approved for preventing ovarian failure
in women with early-stage breast cancer. While doctors can prescribe
it "off-label," Albain said it is not clear whether insurance
companies would cover it.
"We have to hope that will get settled relatively quickly," she
Dr. Claudine Isaacs of Georgetown Lombardi Comprehensive Cancer
Center, who was not involved in the study, noted that younger women
often survive breast cancer. "Anything we can do to allow these
women to live a normal life is the goal.”
(Reporting by Julie Steenhuysen; Editing by Michele Gershberg and
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