Treatment for metastatic breast cancer - what this means for you

12 Oct 2021

We look at a summary of treatments to discuss with your care team. 

If you’ve been given a diagnosis of metastatic breast cancer you may also hear the term ‘stage 4 breast cancer’. These two terms are the same and refer to breast cancer which has spread beyond the part of the body where it started (usually the breast). 

When treating metastatic breast cancer, your team is aiming to control the growth and spread of the cancer. This includes treatments to help relieve symptoms, pain and improve or maintain your quality of life. 

This can be a confusing time, so we have summarised the most common treatments below for your reference and to discuss with your multidisciplinary team. There may be some medications that aren’t readily available on the PBS but have shown efficacy in other clinical trials and it’s always worth asking and exploring these options with your treating team. 

When considering which treatment is best for you your team will consider various details to help determine your care journey. This details include:

  • Where in the body the breast cancer has spread to
  • The level of hormone receptors in the tumour (if present)
  • Gene mutations within the tumour
  • Previous treatment you may have received for your breast cancer (if any)
  • Overall health and other health problems
  • Medications you’re currently taking.

Therapies that use medication to destroy are called systemic therapy. The medication is injected into the bloodstream via an intravenous (IV) tube placed in a vein using a needle, or by a pill or capsule, in order to reach the cancer cells. Treatment is administered by your oncologist. 

If your doctor or care team suggests systemic therapy for your treatment plan, this may include hormonal therapy, chemotherapy, targeted therapy and immunotherapy, or a combination of these. Your initial treatment is called first-line treatment; your second line treatment is when a combination of drugs are given, or could include surgery and/or radiation therapy.

Remember: everybody is different; every person who is diagnosed with cancer will have a different treatment plan. 


Types of treatment you may be offered

Hormonal therapy: 

This form of treatment is typically used as the first line of treatment for women with hormone positive metastatic breast cancer. It can be used on its own, or alongside other forms of treatment. Hormone therapy is used to treat women who have hormone receptors on their breast cancer cells – this means the cancer cells are affected by female hormones. It’s estimated that two-thirds of breast cancers are hormone receptor positive. This type of breast cancer needs the female hormones oestrogen and/or progesterone in order to grow and reproduce. 

How treatment works: Hormone therapy stops oestrogen from feeding the breast cancer and reduces the risk of cancer spreading through the body.

Form of treatment: These can be either in the form of tablets or injections or a combination of both. Treatment usually continues indefinitely in the setting of metastatic breast cancer and is stopped due to significant side effects, or when it stops working. 

Side effects: hot flushes, heart palpitations or anxiety, night sweats, insomnia or wakefulness, tiredness, fatigue, joint pain, vaginal dryness. Long term side effects on your cardiovascular health and bone health would need to be discussed with your doctor in the setting of the extent of the metastatic disease also. 

Speak to your doctor about whether a bone mineral scan (DXA or DEXA scan) is recommended for you prior to beginning treatment. Calcium and vitamin D levels should also be checked.


This form of treatment is used to treat metastatic breast cancer by destroying or damaging the cancer cells. Chemotherapy affects the entire body, so it is recommended when: there is a large amount of cancer in the organs,  if the cancer is growing quickly, or in certain types of breast cancer such as Her 2 positive or triple negative breast cancer

Chemotherapy can be used alongside other targeted therapies, which are working to kill cancer cells. Your oncologist will discuss your options with you. 

When side effects become unbearable many oncologists will withdraw, dose reduce or change chemotherapy regimens. 

Targeted therapy

Targeted therapy is different from chemotherapy as it is designed to attack cancer cells without harming any healthy cells but can be used alongside chemotherapy and also attacks specific molecular targets which are thought to be the driver of the cancer growth. People who undergo targeted therapy are less likely to suffer from chemotherapy related side effects. 

How treatment works:The treatment tells the body to block the growth pathway that tells cancer cells to grow. There are different types of targeted therapies – other types also deliver substances directly to proteins in the cancer cells to destroy them or prevent them from growing and spreading. This means that it’s less likely that healthy cells are killed alongside cancer cells during treatments. 

Immunotherapy medicines call upon your body’s own immune system to help attack and fight cancer cells and may play a small role in certain types of breast cancers, but this will need to be discussed with your oncologists

Your oncologist may use one of many targeted therapies to fight your metastatic cancer. It’s best to discuss this medication with them, treatment schedule, side effects and expected outcomes. 


Clinical trials

You may be offered the option of considering a clinical trial as part of your treatment plan. A clinical trial is a research study conducted by doctors to learn more about new treatments – whether they are effective, safe and possibly a better option than current treatments. When considering a clinical trial as a part of your treatment plan, it’s important to find out everything you can about the side effects and treatment schedule.