TUESDAY, July 9 (HealthDay News) -- Women at high risk of breast
cancer should discuss with their doctors the use of so-called
chemopreventive drugs to reduce that risk, according to a new
practice guideline issued by the American Society of Clinical
The new guideline updates the previous one, issued in 2009, said
Dr. Kala Visvanathan, director of the clinical cancer genetics and
prevention service at the Johns Hopkins Sidney Kimmel Comprehensive
Cancer Center, who co-chaired the guidelines panel.
"It's a stronger recommendation for discussion of these agents," she said, explaining that the previous guideline suggested the discussion. The new guideline also adds an additional drug option for breast cancer risk reduction.
The guideline was published online July 8 in the
Journal of Clinical Oncology.
The key points include a recommendation to discuss the use of
tamoxifen (Nolvadex, Tamofen, others) with premenopausal women at
high risk, and tamoxifen and raloxifene (Evista) with
postmenopausal women. The guideline adds another alternative,
exemestane (Aromasin), for postmenopausal women.
Visvanathan and other panel members looked at 19 published
articles to assess the risks and benefits of using the drugs to
reduce breast cancer risk.
The panel recommended various doses of the drugs, taken daily
for five years, to reduce risk. Tamoxifen and raloxifene target
estrogen receptors and work to reduce the risk of estrogen
receptor-positive, or ER-positive, cancers, which need estrogen to
Exemestane lowers the amount of estrogen in the body. It is not
yet approved by the U.S. Food and Drug Administration for breast
cancer prevention, but a study has found it can reduce risk by up
to 70 percent over three years.
The guideline is meant for women who are cancer-free but at high
risk for breast cancer, Visvanathan explained. "We aren't talking
about breast cancer survivors and we aren't talking about all
women," she said. The guideline only recommends discussing the
drugs with a doctor, not that women at high risk should absolutely
take them, she added.
Women should talk about the risks and benefits of the drugs to
reduce their breast cancer risk and then decide, she said.
Who might fit this profile of high risk? A woman in her 40s who
has a condition called atypical hyperplasia, an abnormality in
breast cells that has been linked with higher risk of breast
cancer, should discuss the use of the drugs, Visvanathan said. So
should a woman in her 50s with a family history of breast cancer
and who has never given birth.
Women with the BRCA1 and BRCA2 gene mutations, known to boost
breast cancer risk, should also discuss the drugs with their
doctor, she said, ''although they have other preventive options as
More than 2 million U.S. women could benefit from these drugs,
according to the researchers. However, few women take the
According to one study published in 2010, only about 1 percent
of women, or about 20,000, took tamoxifen as a preventive drug.
About four times that number took raloxifene.
For some women, taking the drugs may reduce their risk up to 50
percent, Visvanathan noted.
Side effects, or fear of them, are one reason women decline the
drugs, Visvanathan explained. Among the side effects are hot
flashes, vaginal dryness and decreased sex drive.
The new, stronger guideline is a good idea, said Dr. Otis
Brawley, chief medical officer for the American Cancer Society, who
reviewed the guideline but was not involved in writing it.
"We're very supportive of [the recommendations]," he said.
Following the news about actress Angelina Jolie's decision to
have a preventive double mastectomy to reduce her higher risk of
breast cancer due to a BRCA mutation, Brawley said the new
guideline will bring some needed focus to other risk-reduction
While Brawley said he supports Jolie's decision, ''there is a
group of women at increased risk for whom one of these preventive
drugs would be much more appropriate for them and much better for
their lifestyle," he explained.
"For some women at increased risk, taking these drugs and closer surveillance could be a better option than bilateral mastectomy," he added.
The drugs, Brawley said, make mammography more effective. "There
are studies to show these drugs decrease breast density and
therefore increase the ability of mammography [to detect
"Ultimately a woman needs to make a decision," he said.
Some members of the panel report consultant work, honoraria,
stock ownership or research funding from Novartis, Pfizer, Bayer,
Champions Biotechnology or AstraZeneca.
To learn more about breast cancer risk, visit the
American Cancer Society.