Myths, Hopes, and Facts About Breast
Cancer
For: Ask the Experts, September 2002
Breast cancer is the disease that women fear most, according
to many surveys—and the subject of scores of magazine articles, TV
shows, websites, and books. Women trying to keep up have to weed through
a pile of information, misleading and confusing statements, and deliberate
misinformation (such as the Internet rumors that antiperspirants and underwire
bras cause breast cancer: they don't). Here's what people are
saying, and asking.
Stress and breast cancer: cause and effect?
There's no evidence that emotional upset or severe
stress (tem-porary or chronic) causes breast cancer, or causes it to recur
after treatment. Or indeed that personality or attitude has any relation
to breast cancer. This is a myth—and a heavily promoted myth. True
or not, a recent study in Psycho-Oncology reports that a high percentage
(42%) of women who had survived breast cancer by at least two years believed
stress was to blame for the cancer. About 26% blamed genetics (a better
guess), and 25% the environment (surprisingly little is known about this).
The researchers concluded that doctors should ask their
patients what they think about the causes of breast cancer. It might be
comforting for a woman to learn that her emotions did not "give"
her breast cancer.
Women whose cancer had not recurred were asked what they
thought had kept them healthy. An even higher proportion (60%) attributed
their survival to a positive attitude. They cited good diets, exercise,
stress reduction, luck, and taking tamoxifen, among other things. Indeed,
doctors do think that what's called a "fighting spirit"
can boost a woman's chances of survival.
In other words, you don't give yourself breast cancer.
But a positive attitude, including a willingness to comply with treatment,
may indeed help you get well.
Mammograms: outmoded?
In spite of what you may have read, mammography is still
the gold standard for detecting breast cancer, and it's likely to
remain the gold standard for some time. This comes from a new detailed
report from the Institute of Medicine, part of the National Academy of
Sciences. A committee appointed by the Institute and headed by Dr. Joyce
Lashof (Associate Chair of our Editorial Board) reviewed the evidence
and found that mammograms have reduced the mortality rate from breast
cancer by one third in women aged 55 to 70.
And a subsequent study in the journal Cancer claimed
even greater benefits. In Sweden, where 85% of women age 40 to 69 get
the test, the death rate from breast cancer among women having mammograms
was two-thirds less than that of women who didn't get screened. This
was not a controlled study, and may have over-estimated the benefit. Still,
it adds support for mammograms. While they don't prevent breast cancer,
they can detect it at early, treatable stages, which is why the mortality
rate has dropped.
Our recommendations still hold: all women should begin having
annual mammograms at age 50. Women at higher risk for breast cancer, in
consultation with their physicians, may need to start mammography at 40.
New screening tests are also coming into use. Here are three
that may one day be widely used in addition to conventional mammography:
Full-field digital mammography: a very similar process for the woman,
but it uses electronic detectors and produces digital images that can
be easily stored. So far it doesn't look any more accurate than regular
mammograms, and it's more costly. But it may prove to be a better
tool for women with dense breasts.
Magnetic resonance imaging (MRI):
widely used already, but not to detect breast cancer. MRI, which
uses a magnetic field to create an image, may be useful for detecting
less common forms of breast cancer, and for women with dense breasts.
As the technology improves, its usefulness for detecting breast cancer
may also improve.
Ductal lavage: a very thin
catheter is inserted into the milk ducts, where most cancers originate,
and cells are extracted. It's FDA-approved as an adjunct to mammography
and already in use for high-risk women. It might one day be useful for
detecting precancerous cells and thus allow for preventive treatment—in
much the same way that a Pap test can detect potential cancers of the
cervix. But ductal lavage has drawbacks—in particular, too many false
positives—and is not ready for wide use.
Other methods are already in use:
ultrasound is a useful adjunct to mammography; and genetic testing
can help some high-risk women make treatment decisions. Some new scanning
techniques are still in the developmental stage. And new biological knowledge
(that is, understanding of the nature of tumors and potential markers
that may reveal the presence of tumors) will help in diagnosis as well
as treatment.
While mammography is not perfect, it is still the best of
the tests. And don't forget regular breast exams by a professional,
as well as the monthly breast exams you do yourself.
Older women: not at risk?
The idea that breast cancer is a young woman's disease
is untrue, and may have arisen from many articles in women's magazines
about young women with breast cancer. In fact, breast cancer risk rises
dramatically with age. A recent study of Canadian women aged 50 to 75
found, however, that women aged 70 to 75 were less likely to get mammograms.
The reasons for this were complex: fear of the test and of results played
a role, but so did the mistaken idea that older women are less susceptible
to breast cancer. Fatalism stopped some women: "If I get it, I get
it—no point worrying." This is not a constructive way to think
about your health.
Women who get regular blood pressure checks, exercise, and
don't smoke are more likely to get mammograms, whatever their age,
according to research. It makes sense to take good care of yourself
in all the ways you can—which includes getting regular mammograms—into
your seventies and eighties and beyond.
UC Berkeley Wellness Letter, July 2001
