Chemotherapy for breast cancer is usually given over three to six months, with three-week cycles. For instance, if you had chemotherapy today, you might receive the next treatment in three weeks, allowing you a period of recovery between treatments. If you have advanced breast cancer, treatment may be continued beyond six months.
In some cases, you and your doctor may choose cycles of chemotherapy that are closer together, such as every two weeks (dose-dense chemotherapy) rather than three. This may decrease the risk of recurrence, but it can also lead to more intense side effects.
Adjuvant chemotherapy is usually started two to six weeks after surgery.
Common drug combinations
There's an array of chemotherapy drugs available. Because each woman is different, doctors tailor certain types and doses of medications (regimens) — often a combination of chemotherapy drugs — to a woman's type of breast cancer and her personal medical history. In general, chemotherapy regimens fall into the following categories:
- Anthracycline-based regimens. Anthracyclines are anti-tumor antibiotics that work in all phases of a cell life cycle. They're widely used for a variety of cancers, including breast cancer. Examples of anthracyclines include doxorubicin, epirubicin and idarubicin (Idamycin PFS). These are frequently combined with other drugs, such as cyclophosphamide (Cytoxan) and fluorouracil (5-FU). Anthracyclines are more often associated with hair loss and vomiting, as well as a long-term risk of heart damage when given in high doses. If you have an existing heart condition, your doctor may avoid an anthracycline-based regimen.
- Alkylating agents. Cyclophosphamide is one of the most commonly used of these agents. Cyclophosphamide works to stop cancer cells from reproducing. It's typically used in combination with an anthracycline, methotrexate (Trexall) or 5-FU. Methotrexate and 5-FU are antimetabolites that interfere with cancer cell growth by substituting key protein building blocks. High doses of cyclophosphamide carry a risk of leukemia developing many years later and of possible damage to the bladder.
- Taxanes. Taxanes (Taxol, Taxotere) inhibit mitosis, the phase in a cell cycle where the cell splits in two. By doing this, they can inhibit tumor growth. Taxanes are some of the most recently developed chemotherapy drugs. They're often added to an anthracycline-based regimen to increase the overall survival benefit. Taxanes tend to cause fewer side effects such as nausea and vomiting, but they are associated with nerve damage at high doses.
Where chemotherapy is given
Chemotherapy sessions are generally given on an outpatient basis. Most breast cancer chemo sessions take place at one of these places:
- A doctor's office
- An outpatient unit in a hospital or clinic
How chemotherapy is given
Chemotherapy drugs can be given in a variety of ways, including pills you take at home. But most often they're given with an injection into a vein (intravenously, or IV). This can be done through:
- An IV needle and tube (catheter) in your hand or wrist.
- A catheter port implanted in your chest prior to beginning chemotherapy. This port stays in place for the duration of your chemotherapy treatment and eliminates the need to find a suitable vein at each treatment session.
A typical chemotherapy session
Not all chemotherapy sessions are alike, but a typical session might follow this order:
- You meet with the health care provider who's administering your chemotherapy.
- You undergo a brief physical exam to check temperature, pulse and blood pressure.
- You have the IV catheter inserted.
- You have a blood sample drawn for a blood count and other blood tests.
- You meet with your doctor to review your blood test results and assess your overall health.
- Your doctor orders the chemotherapy.
- You receive medications to prevent side effects such as nausea, anxiety or inflammation.
- You receive the chemotherapy drugs. This may take up to several hours (in some cases, such as if you're hospitalized, the drugs may be given over several days by continuous infusion).
After a chemotherapy session
Following a chemotherapy session, you may:
- Have your catheter removed.
- Have your vital signs checked.
- Review side effects with your health care provider.
- Receive prescriptions for medications you can take at home to help with side effects.
- Be advised to drink a lot of fluids.
- Receive instructions on proper handling of bodily fluids, such as urine, stool, vomit, semen and vaginal secretions, as these may contain some of the chemotherapy drugs for the next 48 hours. This may simply involve flushing the toilet twice after use.
Some women feel fine after a chemotherapy session and can return to their regular schedules, but others may feel side effects more quickly. You may want to arrange for someone to drive you home afterward, at least for the first few sessions, until you see how you feel afterward.
During the course of chemotherapy
After a few sessions, you may be able to predict more accurately when you'll feel fine and when you may need to cut back on activities. Marking your calendar or keeping a journal may help you track your general response to chemotherapy sessions and help you plan events accordingly.
Following your treatment plan closely is the best way to get the most benefit from your chemotherapy. If side effects become too bothersome, discuss them with your doctor. It's likely he or she will be able to adjust the dose or type of chemotherapy medication you're receiving or prescribe other medications to help minimize side effects.
Oct. 23, 2010
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