Chemotherapy is commonly used to treat breast cancer.
Chemotherapy is the use of anti-cancer (cytotoxic) drugs to treat cancer. It is usually a systemic therapy that circulates throughout the body and destroys cancer cells, including those that may have broken away from the primary tumour.
Chemotherapy may be used:
- after surgery to destroy cancer cells left behind and to reduce the risk of the cancer recurring (adjuvantadjuvantTreatment given in addition to the first-line therapy (the first or standard treatment) to help reduce the risk of a disease (such as cancer) coming back (recurring). chemotherapy)
- If radiation therapy is included in the treatment plan, chemotherapy is often given before radiation.
- before surgery to shrink a large breast tumour (neoadjuvantneoadjuvantTreatment given to shrink a tumour before the first-line therapy (the first or standard treatment), which is usually surgery. chemotherapy).
- to treat a breast cancer recurrence
- to relieve pain or to control the symptoms of advanced breast cancer (palliative chemotherapy)
Deciding on chemotherapy as a treatment option
The decision to offer chemotherapy for breast cancer, and the chemotherapy drugs used, is based on:
- the stage of the breast cancer
- the risk of recurrence, including:
- a woman’s overall health, age and previous medical conditions (such as heart disease)
- Women with some heart conditions may not be able to take certain drugs because there is a risk that they may cause heart damage.
- any chemotherapy treatments that a woman may have already had
- Women who have already been treated with certain chemotherapy drugs (such as anthracycline drugs) may not be able to take more of these drugs.
- a woman’s personal situation and preferences
- Some women may want to have chemotherapy given over a shorter length of time.
- Some women may choose certain drug combinations because they have fewer side effects like hair loss, nausea or changes in fertility.
Chemotherapy is not offered for in situ (stage 0) breast cancers because the risks for recurrence or the cancer spreading to other parts of the body are very low with non-invasive tumours.
Chemotherapy is usually recommended for breast cancer in the following situations:
- stage I or II breast cancer that has a high risk of recurrence
- locally advanced breast cancer
- This includes a large tumour that cannot be removed by surgery and that has spread to other areas of the breast and to the lymph nodes, but not to other parts of the body
- metastatic or recurrent breast cancer that is hormone receptor negative, is growing rapidly or is causing severe symptoms
Chemotherapy may be offered as a treatment option for breast cancer in the following situations, after the benefits and risks of therapy are discussed:
- stage I or II breast cancer that has a moderate (intermediate) risk of recurrence
- metastatic or recurrent breast cancer that is hormone receptor positive
Drugs, doses and schedules vary from woman to woman.
Chemotherapy for early stage (stage I and II) breast cancer is not usually given as a single drug. Drugs are more commonly used in combination with one another because this has been shown to be more effective.
- The different combinations of drugs used to treat breast cancer have similar effectiveness.
- Different chemotherapy combinations may be preferred for women with breast cancer that has spread to the lymph nodes (node positive), locally advanced breast cancer or inflammatory breast cancer.
- Women with HER2-positive breast cancer may also be given biological therapy with certain chemotherapy combinations.
The most common chemotherapy combinations used to treat breast cancer are:
- doxorubicin (Adriamycin) and cyclophosphamide (Cytoxan, Procytox)
- AC – Taxol
- doxorubicin and cyclophosphamide, followed by paclitaxel (Taxol)
- AC – Taxol (dose dense)
- doxorubicin and cyclophosphamide, followed by paclitaxel, with less time between treatments (dose dense)
- This combination is usually given with filgrastim (Neupogen) or pegfilgrastim (Neulasta), which are granulocyte colony-stimulating factorsgranulocyte colony-stimulating factorsA substance that stimulates the bone marrow to develop granulocytes (a type of white blood cell). Granulocytes help defend the body against bacteria, viruses and types of fungus..
- docetaxel (Taxotere) and cyclophosphamide
- TAC (or DAC)
- docetaxel, doxorubicin and cyclophosphamide
- FAC (or CAF)
- cyclophosphamide (by mouth), doxorubicin and 5-fluorouracil (Adrucil, 5-FU,)
- cyclophosphamide (by mouth), epirubicin (Pharmorubicin) and 5-fluorouracil
- cyclophosphamide (into a vein – intravenous), epirubicin and 5-fluorouracil
- FEC – T
- cyclophosphamide, epirubicin and 5-fluorouracil, followed by docetaxel
- CMF – IV
- cyclophosphamide (intravenous), methotrexate and 5-fluorouracil
- CMF – PO
- cyclophosphamide (by mouth), methotrexate and 5-fluorouracil
- Taxol – FAC
- paclitaxel, then followed by cyclophosphamide, doxorubicin and 5-fluorouracil
- doxorubicin and docetaxel
- EC – GCSF
- epirubicin and cyclophosphamide, with filgrastim
- docetaxel and carboplatin (Paraplatin, Paraplatin AQ)
- gemcitabine (Gemzar) and docetaxel
- gemcitabine and paclitaxel
- capecitabine (Xeloda) and docetaxel
Certain chemotherapy drugs may be used alone to treat advanced or metastatic breast cancer. They may also be given to women who have breast cancer that is no longer responding to other treatments. This is because single drugs have fewer side effects than combinations.
- vinorelbine (Navelbine)
- etoposide (Vesepid, VP-16) (by mouth)
- mitomycin (Mutamycin)
- protein-bound paclitaxel (Abraxane)
- The protein helps get the active drug (paclitaxel) into the cancer cells more easily.
- eribulin (Halaven)
- Eribulin may be used to treat metastatic breast cancer in women who have received at least 2 other chemotherapy regimens for metastatic disease. Previous therapy should have included an anthracycline (such as doxorubicin or epirubicin) and a taxane (such as paclitaxel or docetaxel).
For more detailed information on specific drugs, go to sources of drug information.
Supportive care drugs
Colony-stimulating factors may be given with some chemotherapy combinations used to treat breast cancer to help lessen the following side effects:
- neutropenia – a reduction in neutrophils, which are a type of white blood cell
- anemia – a reduction in the number of red blood cells
Antibiotics may be prescribed to reduce the chance of infection during chemotherapy, especially during dose-dense treatments.
See a list of questions to ask your doctor about chemotherapy.