When
a cancer spreads to a different organ, it's known as a distant
recurrence, or a metastasis. If your breast cancer spreads to your
lung, liver, or bones, that does not mean that you now have lung
cancer, liver cancer, or bone cancer. It's still breast cancer.
Most recurrences are diagnosed because of symptoms noticed by the
woman. These symptoms include bone pain, shortness of breath, lack of
appetite and weight loss, and neurological symptoms like pain or
weakness or headaches. Diagnosing metastatic disease early on a scan or
blood test does not make the treatment easier or more effective. This
means you do not have to kick yourself for not complaining sooner.
The treatment approaches to metastatic disease are different from the
approaches to primary breast cancer. With metastatic disease, the goal
is to put cancer into remission and to keep it there as long as
possible in order to prolong survival. At this point, nothing we know
of can guarantee a cure for metastatic breast cancer. However, as new
therapies are continuously being developed, we have reason to hope that
we can one day convert metastatic breast cancer into a chronic disease.
Recent studies suggest that in certain situations where the recurrence
is limited and the woman can be rendered disease-free, 3–30 percent of
women with metastatic breast cancer can be put into remission for more
than 20 years. Unfortunately, though, the average survival for women
with metastatic breast cancer is three years. But 22 percent of
patients live five years, and about 10 percent live more than 10 years.
And 2–3 percent are cured.
It's important to keep in mind that all this is just statistics. What
happens to an individual woman may or may not conform to the norm. I've
had patients with metastatic disease who have far outlived the most
optimistic prognosis. We can't accurately predict the course of
anyone's illness. Metastatic disease is very unpredictable.
During and after your treatment for metastatic disease you'll be
followed with staging tests—bone scan, chest X-ray, and blood tests—as
well as with CT scans, PET scans, or MRI. These tests and scans can
help to determine if you're responding to treatment, although your
symptoms are in fact the best test of effectiveness than these tests.
Below you will find information about:
- Hormonal
(Endocrine) Treatments for Premenopausal Women
- Hormonal (Endocrine) Treatments for Postmenopausal Women
- Chemotherapy
- Targeted Therapy
- Bisphosphonates
- Radiation
Hormonal (Endocrine) Treatments for Premenopausal Women
Metastatic disease in premenopausal women with hormone-sensitive tumors
(estrogen receptor [ER]- and/or progesterone receptor [PR]-positive) is
first treated with endocrine treatments. When a woman has responded to
one hormone therapy, we know she's likely to respond to a second and
possibly a third, so we use them serially.
Ovarian ablation (stopping ovarian functioning) either by surgical or
chemical means is the first line of treatment for premenopausal women
(women who are still menstruating). The drugs used to induce a
reversible menopause are the gonadotropin-releasing hormone (GnRH)
agonists such as leuprolide (brand name Lupron) or goserelin (brand
name Zoladex). Removing the ovaries or stopping their functioning will
put a woman into immediate menopause, complete with mood swings and hot
flashes. But it also can almost immediately relieve metastatic breast
cancer symptoms.
If ovarian
ablation is effective, no other treatments are necessary until symptoms
recur. Then, the next step is to try tamoxifen or an aromatase
inhibitor. The aromatase inhibitors—anastrozole (brand name Arimidex),
letrozole (brand name Femara), and exemestane (brand name Aromasin)—can
only be used if the ovaries have been removed or if a woman continues
to take a drug like Lupron or Zoladex to induce menopause. If this drug
stops working, the next step would be fulvestrant (brand name Faslodex)
and, following that, megestrol acetate (brand name Megace), which is a
kind of progestin. Both of these can only be used if the ovaries have
been removed or a drug like Lupron or Zoladex is being taken.
Some women will experience a phenomenon called "flare" with hormonal
treatment of metastatic breast cancer. A flare can occur within the
first month of therapy and is signified by an exacerbation of the
patient's disease. Although it sounds bad, it actually indicates a good
prognosis. Typically it occurs with someone who has bone metastasis and
is put on tamoxifen. Suddenly the pain is worse than ever. But then
it's back to normal soon after. Oncologists think this happens because
tamoxifen can actually work initially as a weak estrogen in some women,
stimulating their cancer, before it starts to function as an
anti-estrogen. A flare can be very scary. A flare can also occur in the
tumor markers. This is important to know because your doctor, seeing a
rise in the markers, might assume that the treatment is not working,
instead of recognizing the flare as a sign that it is working.
Hormonal options are increasing rapidly. For more information on
current recommendations, you can review the National Comprehensive Cancer Network Breast Cancer Treatment Guidelines.
New medications and new combinations of medications are being tested
all of the time, which means a clinical trial may be the best choice
for someone with metastatic disease. Learn more in our section on Clinical Trials.
Once a premenopausal woman stops responding to hormones, chemotherapy
will probably be used.
Hormonal (Endocrine) Treatments for Postmenopausal Women
Metastatic disease in postmenopausal women with hormone-sensitive
tumors (estrogen receptor [ER]- and/or progesterone receptor
[PR]-positive) is treated first with endocrine treatments. When a woman
has responded to one hormone therapy, we know she's likely to respond
to a second and possibly a third, so we use them serially.
Women who are postmenopausal (whether by chemotherapy or naturally) can
use an aromatase inhibitor, such as anastrozole (brand name Arimidex),
letrozole (brand name Femara), or exemestane (brand name Aromasin). If
the aromatase inhibitors stop working, the next step is to try
fulvestrant (brand name Faslodex), which is a different type of
estrogen receptor blocker. If this stops working, you can move on to
megestrol acetate (brand name Megace), which is a kind of progestin.
Hormonal options are increasing rapidly. For more information on
current recommendations, you can review the National Comprehensive Cancer Network Breast Cancer Treatment Guidelines.
New medications and new combinations of medications are being tested
all of the time, which means a clinical trial may be the best choice
for someone with metastatic disease. Learn more in our section on Clinical Trials.
Once a postmenopausal woman stops responding to hormones, chemotherapy
will probably be used.
Chemotherapy
If a woman's tumor is estrogen receptor (ER)-negative and progesterone
receptor (PR)-negative or if her tumor is hormone-sensitive but is no
longer responding to hormone treatments, chemotherapy is used.About 13
different types of chemotherapy drugs are used commonly in breast
cancer treatment. Interestingly, breast cancer creates the kind of
tumor that is responsive to the greatest array of drugs—most other
cancers don't respond to as many chemicals. The standard drugs are:
- cyclophosphamide
(brand name Cytoxan)—the C in a chemo regimen
- methotrexate—the M in a chemo regimen
- 5-fluorouracil
(also known as 5-FU)—the F in a chemo regimen
- doxorubicin
(brand name Adriamycin)—the A in a chemo regimen
- epirubicin—the E in a chemo regimen
- paclitaxel
(brand name Taxol) or docetaxel (brand name Taxotere)—the T in a chemo
regimen
These drugs have the highest antitumor activity among all the patients
studied, and only limited cross-resistance. There are also other drugs
not used in the adjuvant setting that can be used as well. You can
learn more about the different drugs used for chemotherapy to treat
breast cancer here.
New medications
and new combinations of medications are being tested all of the time,
which means a clinical trial may be the best choice for someone with
metastatic disease. Learn more in our section on Clinical Trials.
Targeted Therapy
Several drugs have been developed to target other molecules that might
be specific to the cancer cells. One of these drugs is called
trastuzumab (brand name Herceptin). It is used to treat women whose
tumors are HER2-positive. All women with HER2-positive metastatic
breast cancer should receive Herceptin either alone or with
chemotherapy, unless they have preexisting heart failure. When or if
breast cancer progresses on Herceptin, it is not clear whether the
antibody should be continued. This is currently being studied.
Another drug now being studied for use in metastatic breast cancer is
called bevacizumab (brand name Avastin). It is an antibody to VEGF, a
growth factor responsible for inducing new blood vessels to arise and
feed the tumor. If you are interested in this type of treatment, you
may want to see if you qualify for an Avastin clinical trial. Learn
more in our section on Clinical Trials.
Bisphosphonates
A bisphosphonate is a drug that blocks the resorption (breakdown) of
bone. It has been shown to be very effective in treating bone
metastasis. When there is cancer in the bone, there is an increase in
the resorption, which is one of the reasons the bone gets weaker and
often fractures. Several studies have shown that giving women
pamidronate (brand name Aredia) or zolidronic acid (brand name Zometa)
every four weeks will decrease not only the resorption of the bone but
also the number of new bone metastases that develop and the incidence
of bone fractures. The bisphosphonate clodronate also works well.
Currently no data is available on the optimal drug, dosing, route of
delivery, duration of therapy, best time to start the drug, or how best
to monitor toxicity when a bisphosphonate is being used as breast
cancer treatment. Studies are ongoing. Learn more in our section on Clinical Trials.
Radiation
Radiation for metastatic cancer is the same as for initial breast
cancer, but the treatment is for a different purpose—to alleviate pain
or other symptoms. It usually takes a couple of weeks before the pain
noticeably lessens. The timing is somewhat different too. There are
usually 10 to 15 treatments, spread over two and a half to four weeks.
A smaller dose of radiation is used.
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