If
you have breast cancer
If
you have a breast cancer gene abnormality and you develop breast cancer, your
doctor will work with you to determine how your BRCA status might affect your
treatment decisions. For example, if you have a BRCA1 mutation, the breast
cancer is less likely to be estrogen receptor-positive, which means that you
may not be a candidate for treatment with hormonal therapy. If you have a BRCA2
mutation, however, you are more likely to be a candidate for hormonal therapy.
You’ll
also want to talk with your doctor about reducing the risk of a new, second
breast cancer or ovarian cancer. Women with breast cancer and a BRCA1 or
BRCA2 abnormality have a significantly greater risk of developing a new,
second breast cancer, as well as ovarian cancer.
If
you want to lower your risk of a future breast cancer or ovarian cancer
Whether
or not you’ve ever had breast cancer, knowing that you have a BRCA mutation
means that you are at much greater risk of developing breast and possibly
ovarian cancer in the future. The latest research offers these insights about
strategies for lowering those risks:
Preventive
or "prophylactic" mastectomy,
or removal of both breasts, has been found to reduce the risk of breast cancer
in high-risk women by about 90%. After a diagnosis of one breast cancer in a
woman with a genetic abnormality, the risk of her getting a new breast cancer
is approximately 3% every year (for example, 15% over 5 years). Without BRCA1
or BRCA2, the risk of developing a new breast cancer after one episode of
breast cancer is only 1% per year.
Preventive
or prophylactic oophorectomy,
or removal of both ovaries, can reduce breast cancer risk when it is done
before menopause, because it takes away the body’s main source of the hormone
estrogen. It also can greatly reduce ovarian cancer risk. However, a 2008 study involving more than 1,000
women with BRCA mutations showed that the benefits of ovary removal may be
different depending on the type of mutation:
BRCA1
carriers: Ovary
removal reduced ovarian cancer risk in BRCA1 carriers by 85%, but it did not
significantly reduce their breast cancer risk. Women with BRCA1 mutations are
more likely to develop breast cancers that are not fueled by the hormone
estrogen (estrogen-receptor-negative breast cancer). So removing the ovaries,
the body’s main source of estrogen, did not provide significant benefit in
terms of breast cancer risk.
BRCA2
carriers: Women
with a BRCA2 mutation had a 72% decrease in their risk of breast cancer after
ovary removal. That’s because breast cancer in BRCA2 carriers is more likely to
be estrogen-receptor-positive. The study did not find a significant reduction
in ovarian cancer risk for these women. BRCA2 mutations have not been found to
play as important a role in ovarian cancer risk as BRCA1 mutations do.
More
research is needed, but this study suggests that women may wish to consider
preventive ovary removal in relation to the type of BRCA mutation they have.
Your doctor can help you sort through this information and figure out how the
surgery might benefit you. The surgery can only be performed if you are certain
that you are finished having children.
Tamoxifen is a hormonal therapy
that blocks the effects of estrogen on breast tissue. In the late 1990s, a
clinical trial called the Breast Cancer Prevention Trial first found that
tamoxifen reduced breast cancer risk by 45% to 50% in women considered to be at
high risk for breast cancer. However, later results revealed that the
risk-reduction benefit of tamoxifen appears to be greatest for women with BRCA2
mutations, who tend to develop breast cancers that are fueled by the hormone
estrogen. The trial found that in women 35 years of age or older who had not
been diagnosed with breast cancer and who took tamoxifen, those who were
BRCA2-positive had a 62% reduction in breast cancer risk, while those who were
BRCA1-positive did not have a significant reduction in breast cancer risk. It’s
not clear whether tamoxifen treatment lowers breast cancer risk in
BRCA1-positive women younger than 35 who've never been diagnosed with breast
cancer. Other research has shown that both BRCA1-positive and BRCA2-positive
women previously diagnosed with breast cancer in one breast can lower their
risk of developing a new breast cancer in the opposite breast by taking
tamoxifen.
For
more information on these strategies, visit our sections onProphylactic
Mastectomy, Prophylactic
Ovary Removal, andTamoxifen.
If
you want to try to increase the odds of early detection
Another
option besides preventive surgery is to undergo more frequent cancer screenings
in an effort to catch cancer early, should it ever develop. Although more
frequent screenings do not guarantee early detection of cancer, they are
generally recommended for women who do not wish to have preventive surgery.
You
can work with your doctor to come up with a screening schedule that is right
for you. For example, you might take the following steps:
Begin
annual mammograms at age 25, or 10 years before the earliest age at which a
family member was diagnosed — whichever comes first. Digital mammography may
provide added benefit. MRI (magnetic resonance imaging) of the breasts
performed by experienced centers can also be very useful. Consider
participating in a clinical trial evaluating newer methods of early detection.
If
you have a family history of ovarian cancer, begin annual screening at age 25,
including pelvic exams by a gynecologist, annual pelvic ultrasound with an
intravaginal probe, and blood tests for a special protein called CA-125.
Consider participating in a clinical trial evaluating newer methods of early
detection.
Have
a clinical breast exam every 6 months, and examine your breasts monthly.
Consider
participating in a clinical trial of cancer prevention strategies.
