Chemotherapy for breast cancer

Chemotherapy uses drugs to destroy cancer cells. These drugs target rapidly dividing cells throughout the whole body. This means that chemotherapy kills cancer cells but it can also damage healthy cells.

With most types of chemotherapy, the drugs travel through the blood to reach and destroy cancer cells all over the body, including cells that may have broken away from the primary tumour. This is described as systemic therapy.

Most people with breast cancer have chemotherapy. If you have chemotherapy, your healthcare team will use what they know about the cancer and about your health to plan the drugs, doses and schedules.

Chemotherapy is often combined with other treatments for breast cancer. You may have chemotherapy:

• before surgery (called neoadjuvant chemotherapy) to shrink a large tumour so it can be removed with breast-conserving surgery, and to see how well the cancer responds to certain drugs
• after surgery (called adjuvant chemotherapy) to reduce the risk that the cancer will come back (recur)
• to treat cancer that has come back
• to relieve pain or control the symptoms of advanced breast cancer (called palliative chemotherapy)

Chemotherapy is usually given every 3 weeks, and most chemotherapy drugs used for breast cancer are given through a needle in a vein (by intravenous, or IV).

Dose-dense chemotherapy is given every 2 weeks instead of the usual 3 weeks. It may be used for breast cancer that has a higher risk of coming back.

Neoadjuvant chemotherapy is started before surgery as soon as possible after diagnosis. Adjuvant chemotherapy is started as soon as you have healed from surgery and no later than 12 weeks after surgery.

Different drugs and combinations of drugs are offered for breast cancer. The type of chemotherapy you are offered will depend on:

• the type of breast cancer, including the hormone receptor status and HER2 status
• the stage
• the risk of recurrence
• your overall health, including any heart problems you have
• any previous chemotherapy treatments you have had
• your lifestyle and what you prefer or want

If you want to have children in the future, talk to your healthcare team before you start cancer treatment. They can refer you to a fertility clinic and plan your treatment in ways that support your chances of being able to have children after treatment.

Chemotherapy is most effective when more than one drug is used at the same time (called combination chemotherapy). Combinations can include 2 or 3 drugs. Most chemotherapy combinations used to treat breast cancer include both an anthracycline drug and a taxane drug. Other drugs may be added to the combination.

Your healthcare team will decide which chemotherapy drugs will work best for you. There are many different types of combinations for breast cancer. There isn't any strong evidence that one combination is better than another.

Chemotherapy may be offered for early-stage or locally advanced breast cancer. It may be used before or after surgery.

The following drugs may be combined for chemotherapy before or after surgery:

• anthracycline drugs such as doxorubicin or epirubicin
• taxane drugs such as paclitaxel or docetaxel
• cyclophosphamide
• fluorouracil (also called 5-fluorouracil or 5-FU)
• carboplatin

A targeted therapy drug will be added to some chemotherapy combinations to treat HER2-positive breast cancer. The targeted therapy drug is commonly given with taxane chemotherapy drugs. There is a risk of heart problems if the targeted therapy drug is given with anthracycline chemotherapy drugs.

Metastatic breast cancer means that the cancer has spread to other parts of the body. It is stage 4 breast cancer.

Doctors often use one chemotherapy drug to treat metastatic breast cancer because it causes fewer side effects than a combination of drugs. But a combination may also be used.

There is no standard drug or drug combination for metastatic breast cancer. Chemotherapy is given as long as the cancer responds to it and the side effects do not cause problems. If the cancer stops responding to one drug, your healthcare team may offer to treat you with a different drug or drug combination.

The following drugs may be use for metastatic breast cancer:

• anthracycline drugs such as doxorubicin, pegylated liposomal doxorubicin and epirubicin
• taxane drugs such as paclitaxel, docetaxel and nab-paclitaxel
• capecitabine
• gemcitabine
• vinorelbine
• cyclophosphamide
• carboplatin
• cisplatin
• epirubicin
• eribulin

Chemotherapy for metastatic breast cancer may also be combined with targeted therapy, hormone therapy or immunotherapy.

Recurrent breast cancer is breast cancer that has come back after treatment has finished.

The type of chemotherapy offered for recurrent breast cancer will depend on where the cancer has recurred.

Localized recurrence is when the cancer has recurred in the breast and the lymph nodes around the breast.

Metastatic recurrence is when the cancer has come back in other parts of the body, such as the bones, liver or brain.

Your healthcare team will offer you chemotherapy for recurrent breast cancer based on:

• the hormone receptor status of the cancer
• the HER2 status of the cancer
• the type and number of treatments you have had
• the time between when the cancer was first treated and when it recurred
• your overall health
• your lifestyle and what you prefer or want

The following drugs may be used to treat recurrent breast cancer:

• anthracycline drugs such as doxorubicin, pegylated liposomal doxorubicin and epirubicin
• taxane drugs such as paclitaxel, docetaxel and nab-paclitaxel
• cyclophosphamide
• fluorouracil (also known as 5-fluorouracil or 5-FU)
• capecitabine
• carboplatin

Chemotherapy for recurrent breast cancer is often combined with targeted therapy or hormone therapy drugs.

Side effects of chemotherapy will depend mainly on the drug, the dose and your overall health. Tell your healthcare team if you have side effects that you think are from chemotherapy. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them..

Common side effects of chemotherapy drugs for breast cancer include:

• low blood cell counts
• infection
• nausea and vomiting
• sore mouth and throat
• hair loss
• diarrhea
• constipation
• fatigue
• loss of appetite
• treatment-induced menopause
• cognitive changes
• nervous system damage
• heart problems
• fertility problems

Find out more about chemotherapy and side effects of chemotherapy. To make the decisions that are right for you, ask your healthcare team questions about chemotherapy.

Details on specific drugs change regularly. Find out more about sources of drug information and where to get details on specific drugs.