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Chemotherapy (chemo) uses anti-cancer drugs that are injected
into a vein or given by mouth. These drugs enter the bloodstream and
reach all areas of the body, making this treatment useful for cancers
that have spread to distant organs (metastasized). GTD is one of the
few cancers that can almost always be cured by chemo no matter how
advanced it is.
The drugs that can be used to treat GTD include:
- methotrexate (with or without leucovorin)
- actinomycin-D (also known as dactinomycin)
- cyclophosphamide
- chlorambucil
- vincristine (Oncovin)
- etoposide
- cisplatin
To reduce the risk of side effects, doctors try to give the
fewest drugs at the lowest doses that will still be effective. As a
general rule, women who need to get chemo and fall into the low-risk
group (see the section, "How
is gestational trophoblastic disease staged?") are given a
single chemo drug. Women who fall in the high-risk group usually
receive combinations of drugs, often at higher doses.
Single drug treatment
Methotrexate:
Chemotherapy with methotrexate alone can be used in most women with low
risk disease. The methotrexate can be given as an injection into a vein
or a muscle every day for 5 days. This can be repeated again after a
rest period based on the HCG level. Another way to give methotrexate is
to give a larger dose once a week. Again, the treatment is continued as
long as needed based on the HCG level. Another option is to give
methotrexate along with folinic acid (also called leucovorin).
Leucovorin is not a chemo drug, but instead is a type of vitamin that
reduces the side effects of methotrexate. In this course of treatment,
methotrexate is given on days 1, 3, 5, and 7, and leucovorin is given
on days 2, 4, 6, and 8. Each cycle has 8 days of drug treatment,
followed by a rest period. This method involves more treatment days, so
it may be less convenient, and the rate of resistance may be slightly
higher than with methotrexate given on a daily basis. In all cases,
methotrexate is given in cycles that are repeated until blood levels of
HCG remain normal for a few weeks. Vitamins such as folic acid should
not be taken with methotrexate unless directed by your doctor.
Actinomycin-D:
Another option is to give actinomycin-D (dactinomycin) instead of
methotrexate. This drug may be especially useful in patients with liver
problems, because it is less toxic to the liver than methotrexate is.
Actinomycin-D can be given in a vein (intravenously, or IV) every day
for 5 days, followed by several days without treatment. It is also
given as a larger single dose once every 2 weeks. This schedule seems
to have fewer side effects while still working well. Either way, the
cycles are repeated until HCG levels have stayed in the normal range
for several weeks.
Combinations of drugs
Women with higher-risk disease will receive combinations of
drugs such as methotrexate, actinomycin-D, and cyclophosphamide. Other
drugs such as etoposide, vincristine, and cisplatin may also be used.
Some of the more commonly used combinations include:
- MAC: methotrexate/leucovorin, actinomycin-D, and
cyclophosphamide or chlorambucil
- EMA-CO: etoposide, methotrexate/leucovorin, and
actinomycin-D, followed a week later by cyclophosphamide and
vincristine (Oncovin)
- EMA-EP: etoposide, methotrexate/leucovorin, and
actinomycin-D, followed a week later by etoposide and cisplatin
- VBP: vinblastine, bleomycin, and cisplatin
Possible side effects
Chemo drugs work by attacking cells that are dividing quickly,
which is why they work against cancer cells. But other cells in the
body, such as those in the bone marrow, the lining of the mouth and
intestines, and the hair follicles, also divide quickly. These cells
are also likely to be affected by chemotherapy, which can lead to some
side effects.
The side effects of chemo depend on the type and dose of drugs
given and the length of time they are taken. Common side effects of
chemotherapy drugs include:
- hair loss
- mouth sores
- loss of appetite
- nausea and vomiting
- increased chance of infections (due to low white blood cell
counts)
- easy bruising or bleeding (due to low blood platelet
counts)
- fatigue (due to low red blood cell counts)
Most of these side effects are short-term and tend to go away
after treatment is finished. There are often ways to lessen these side
effects. For example, drugs can be given to help prevent or reduce
nausea and vomiting. Do not hesitate to discuss any questions about
side effects with the cancer care team.
Along with the effects listed above, some side effects are
specific to certain medicines:
Common side effects of methotrexate are diarrhea and sores in
the mouth. This drug can also cause mild liver damage which is seen as
changes in certain blood tests (liver enzymes). Some women experience
inflammation of the eye (conjunctivitis), pain in the chest or abdomen,
irritation in the genital region, or skin rash. Hair loss and blood
side effects do not usually occur with single-drug methotrexate
therapy.
Actinomycin-D can cause fairly severe nausea and vomiting.
This can be prevented by medications given before chemo. Treatment with
actinomycin-D or combination therapy is more likely to result in hair
loss. Your bone marrow's ability to produce blood cells may be
affected, which in turn may lower the ability of your immune system to
fight infection.
Bleomycin can cause lung problems.
Cyclophosphamide can cause some nausea and hair loss. It can
also cause bladder irritation.
In rare cases, etoposide treatment has been linked with the
development of leukemia several years later. But doctors still consider
it important to use because its benefit in curing the cancer outweighs
the small risk of leukemia.
Vincristine and cisplatin can damage nerves (called
neuropathy). Patients may notice tingling and numbness, particularly in
the hands and feet. Cisplatin can also cause hearing loss and kidney
damage. These side effects may persist after treatment is stopped.
You should report any side effects or changes you notice while
getting chemotherapy to your medical team so that they can be treated
promptly. In some cases, the doses of the chemotherapy drugs may need
to be reduced or treatment may need to be delayed or stopped to prevent
the effects from getting worse.
Last Medical Review: 10/13/2009 Last Revised: 10/13/2009
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