Chemotherapy for metastatic breast cancer

Chemotherapy can be used for people with metastatic breast cancer to:

• control or slow down the cancer’s growth
• relieve symptoms
• improve quality of life
• prolong life.

Remember, this is a personal decision for you in consultation with your medical oncologist.

When chemotherapy is used

Chemotherapy is commonly used to treat people with metastatic breast cancer. It is often given first (first line treatment) to people with triple negative and HER2-positive breast cancer.

Chemotherapy will be an option at some point to treat most hormone receptor positive metastatic breast cancer, for people:

• whose HR+ metastatic breast cancer has stopped responding to hormone-blocking therapies
• with HR+ metastatic breast cancer that is growing quickly, especially in the liver or lungs.

Deciding to have chemotherapy is a personal choice. You also need to be medically well enough.

Doctors may consider chemotherapy if:

• the cancer is causing bad symptoms. A course of chemotherapy may give you control of your symptoms. You may be able to return to hormone-blocking therapies afterwards
• they are concerned that metastases in organs such as the lungs or liver are affecting how they work (‘visceral crisis’)
• you develop high calcium levels in the blood (‘hypercalcaemia’)
• it appears that hormone-blocking therapy options are no longer controlling the cancer.

Many different chemotherapy drugs may be effective for hormone-receptor positive metastatic breast cancer.

It is most common to use these treatments individually (as ‘single agents’). Occasionally, you may have two together, in combination.

You can have chemotherapy as long as it is effective in treating the cancer and not causing too many side effects. For some people, chemotherapy can be effective in controlling the cancer for a long time.

Types of chemotherapy drugs for metastatic breast cancer

Many different types of chemotherapy are available.

Your doctor and cancer nurse can explain the possible benefits and side effects of the drugs to you.

It's important to avoid comparing your treatment to others.

When you talk with others who have a similar diagnosis to you, you will probably find they have very different chemotherapy treatment.

There are some guiding principles and government regulations that influence choices of chemotherapy. Your oncologist is the best person to discuss this with.

Common chemotherapy drugs used to treat breast cancer include: 

• mitotic inhibitors such as taxanes, e.g. paclitaxel (Taxol), docetaxel (Taxotere), nab-paclitaxel (Abraxane)
• anthracyclines such as doxorubicin (Adriamycin)
• alkylating agents such as cyclophosphamide
• platinum agents such as carboplatin (Paraplatin)
• antineoplastics such as eribulin (Halaven), vinorelbine (Navelbine)
• antimetabolites such as capecitabine (Xeloda), gemcitibine (Gemzar).

Which type of chemo is best

Your medical oncologist works with you to make the best choice at any given time. You may have 1 chemotherapy drug or a combination of 2 different drugs given via drip, one after the other. Each different drug type or drug combination is called a 'line' of treatment.

Often people have several lines of chemotherapy to keep their cancer under control and prolong life.

It is normal to find that other people with a similar diagnosis are having different chemotherapy treatment.

You and your oncologist will discuss:

any chemotherapy you received previously, such as treatment for early breast cancer. Usually you won’t repeat these chemotherapies, but a taxane chemotherapy may be re-used with good results if more than 12 months have passed

• which chemotherapy has the best chance of working for your subtype of breast cancer
• any PBS restrictions that affect the chemotherapy drugs
• any ongoing side effects from previous treatment, such as nerve damage, skin problems, effects on the heart etc
• your preference for oral or intravenous chemotherapy
• any opinions you have about side effects such as hair loss
• whether you carry a BRCA gene mutation. If you have not been tested for BRCA mutations, talk to your medical oncologist. 

Length of treatment

The cycles of treatment are different for everyone. How long you continue with a chemotherapy course will depend on:

• how well it is controlling the cancer
• how well you are coping with side effects
• whether your side effects might cause longer term problems, such as damage to nerve endings (‘peripheral neuropathy’)
• how you feel about continuing the course
• whether you have any specific commitments or events, such as a planned holiday etc.

The length of your course is an open-ended decision and involves discussion between you and your medical oncologist.

Generally, 6 cycles of treatment are appropriate to start with, as long as:

• the cancer is responding to treatment
• you can manage the side effects.

If chemotherapy works well for you and you are coping with it, it's fine to have back-to-back lines of treatment with a short rest period in between.

Evidence shows that having treatment for longer can make the benefits last longer. But it is important to balance treatment with side effects. It is also important that you don’t have severe side effects that mean you can’t live well.

Treatments can sometimes continue for longer periods - 12 months or more - with prolonged cancer control.

Oral treatments have the added benefit of avoiding many hospital visits for IV drip treatments.

If cancer stops responding to chemotherapy

If the cancer is no longer responding to your current treatment, you may change to other types of treatment or therapy. 

Your medical oncologist will make a recommendation. It will depend on:

• how well the cancer is likely to respond to treatment
• how likely you are to tolerate the treatment
• your wishes about treatment.

They may suggest more hormone-blocking therapy between lines of chemotherapy if you still have hormone-blocking therapy options available.

There is no such thing as a ‘right’ or ‘wrong’ chemotherapy, or a right or wrong time to receive it.

Most people with metastatic breast cancer will have a series of treatments over time. Each treatment will add a period of cancer control.

Your medical oncologist will work with you on the best choice of treatment for you at any given time.

If you decide to stop chemotherapy

Stopping chemotherapy is a big decision, but it is your personal decision.

It is important that you can:

• discuss this decision with your medical oncologist and your family
• make this decision when it feels right for you.

Your oncologist may also suggest you stop chemotherapy completely at some point if they believe:

• you only have a small chance of responding to another line of treatment
• your wellbeing is affected too badly by treatment
• you are not well enough to receive treatment.

Your medical oncologist or treating doctor can talk to you about your options. Read about Stopping breast cancer treatment.

Side effects of chemo

Talk to your treating team if you are concerned about possible side effects. Find out about chemotherapy side effects and how to reduce them.

It’s important you seek urgent medical attention for signs of infection, especially if you have a temperature over 38°C.