Treatment and clinical care

Understanding treatment goals

The main goals are to:

• Control the cancer (by keeping it stable or shrinking it)
• Manage your symptoms and any side-effects of treatment
• Help you live as well as possible for as long as possible

Treatment options

Your plan may include a mix of:

• Systemic therapy - tablets, injections, or medicines through a drip that treat the whole body. This is the main treatment for most people.
• Radiotherapy - a targeted treatment to help with symptoms in a specific area.
• Surgery or procedures - used case by case to solve particular problems.

Systemic therapy

The particular type of systemic therapy will guided by your cancer’s subtype (HR+, HER2-positive, HER2-low, triple-negative):

Hormone Receptor-Positive (HR+):

• Endocrine (hormone-blocking) therapy – medicines that block oestrogen or how it works (e.g. aromatase inhibitors, tamoxifen, fulvestrant).
• CDK4/6 inhibitors (often used with endocrine therapy) – tablets (palbociclib, ribociclib, abemaciclib) that can slow cancer growth and can extend how long endocrine therapy works.
• Targeted therapies (after drug-resistance develops) – Depending on genomic tumour testing, options may include drugs that target PIK3CA or ESR1 gene changes.
• Antibody-drug conjugates (ADCs) – in some people, for example, if your cancer is HER2-low, ADCs, such as trastuzumab deruxtecan, may be an option.
• Chemotherapy - if endocrine therapy and targeted options stop working, or if your cancer is more active and needs a faster response.

HER2-Positive (HER2+):

• HER2-targeted therapies – these treatments seek out the HER2 protein (e.g. trastuzumab, pertuzumab) and are often used with chemotherapy at first, then can be continued on their own.
• Antibody-drug conjugates (ADCs) –Trastuzumab-based ADCs (T-DXd and T-DM1) deliver chemotherapy directly to the HER2-expressing cancer cells.
• HER2-targeted tyrosine kinase inhibitors (TKIs) – these include tucatinib, lapatinib and neratinib. They are used in the second-line setting and beyond, particularly for patients with brain metastases.

Triple Negative (TNBC):

• Chemotherapy – often used as a first-line treatment for people with TNBC.
• Immunotherapy (for some patients) – may be used if your cancer’s tests show it is likely to respond. The most common test checks for PD-L1 expression on the cancer cells.
• PARP inhibitors – are targeted treatments for some people who have the inherited BRCA1/2 mutations
• Antibody-drug conjugates (ADCs) - in some people, for example, if your cancer is HER2-low, ADCs, such as trastuzumab deruxtecan, may be an option.

Your oncologist will explain which treatments are recommended for your specific situation.

Information about clinical trials is included further below.

Radiotherapy (radiation therapy)

Radiotherapy is a local treatment that targets a specific area where the cancer is. It’s often used in metastatic breast cancer to shrink tumours and ease symptoms such as pain or swelling; it doesn’t treat the whole body.

Common reasons to use radiotherapy include painful bone metastases (e.g., to help prevent or treat fractures and to relieve spinal cord compression) and brain metastases (either after surgery or instead of surgery, to control symptoms).

Courses are usually short—sometimes a single session or a few treatments over 1–2 weeks—and many people notice pain relief within days to a couple of weeks.

For small, well‑defined areas (for example, some brain or spine lesions), your team may discuss stereotactic radiotherapy, which delivers a high dose precisely and can be used alongside systemic therapy when appropriate.

Side‑effects depend on which part of the body is treated (e.g., tiredness, skin changes, nausea for some sites) and your team will explain what to expect and how to manage them.

The role of surgery in MBC

If you are diagnosed with de novo MBC (stage IV), it is unlikely you will be offered breast surgery (e.g. a mastectomy or lumpectomy). You might wonder why. Breast surgery usually doesn’t improve survival when the cancer has already spread to distant sites in the body. Most people are best served by systemic treatments (medicines that treat the whole body).

However, other types of surgery may still be considered when it can solve a specific problem, for example:

• Stabilising the spine if there’s a risk of collapse or nerve pressure.
• Fixing or preventing fractures in weight‑bearing bones.
• Removing a single or small number of tumours in the brain or to drain fluid.
• Relieving pressure or blockage in organs.

Bottom line: Surgery in MBC is targeted for symptom relief or structural safety, and decisions are made case by case.

Scan frequency and what results mean

How often you have scans is individualised. Many people have scans every 2-3 months when starting or changing treatment. If you’re cancer stays stable for a while, scans may be done less often (for example, every 6 months). If your symptoms change, scans might be brought forward.

Different types of scans and what they can show

Different scans can use different wording to report the results. PET scans comment on metabolic activity (how ‘active’ the cancer looks). CT/MRI often use size-based categories to indicate the size of your tumour(s).

• Complete metabolic response (CMR) – On a PET scan, there’s no abnormal activity suggesting that there is no active cancer. This can happen, though it’s uncommon. Your team will keep an eye on things over time.
• No evidence of active disease (NEAD) – A term you may hear to describe a complete response, where there is no visible or detectable active cancer on your scans. It’s important to remember that this is a current snapshot, not a promise for the future, so regular follow‑up continues.
• Partial response – Your cancer has shrunk by a meaningful amount.
• Stable disease – Your cancer hasn’t grown or shrunk much. This is often a good result as it means your treatment is holding things steady.
• Progressive disease – Your cancer has grown or new areas have appeared. Your team will talk with you about next steps, which might include changing or adjusting treatment.

Sometimes scans show a mixed response. Some areas improve while others don’t. Your team will consider the whole picture (your symptoms, your blood and other test results, other treatment options) before recommending changes.

Scans and your mental wellbeing

Regular scans can be stressful. Many people call this ‘scanxiety’. It’s important to look after your mental wellbeing before and after scans.

If you’re very anxious beforehand, ask your doctor about short‑term medication to help you feel calmer (especially for MRI claustrophobia). You can also use simple grounding or breathing exercises to calm yourself during the scan. Some centres allow music or podcasts during scans.

If it’s possible, try to book your scan a few days (rather than weeks) before you see your oncologist. This gives your clinical team enough time to review the images but means you won’t wait too long to hear the results.

Bring a support person if you can, both to the scan and to the results appointment.

Let your doctor know how you want to receive your scan results (in person, with a support person, or by phone).

Find more information about mental health in Living with MBC.

Managing treatment

Side effects and when to report symptoms

Side effects vary by treatment. Some of the more common ones include:

• Fatigue
• Sleep issues / insomnia
• Nausea or changes in appetite
• Peripheral neuropathy (tingling, numbness in hands/feet)
• Cognitive changes (‘brain fog’)
• Hair thinning
• Changes in mood (low mood, anxiety, irritability)

If side effects are having a big impact on your day-to-day life, talk with your care team. Options might include treatment dose adjustments, spacing treatments further apart, switching treatments or including supportive medicines (for nausea, pain, sleep, bowels, mood).

Managing common side effects

Side effects can continue or change over time, especially as treatments change. Let your care team know early as small tweaks can potentially make a big difference.

• Fatigue Pace yourself, especially after treatment. It might help to plan just one main task a day and rest when you need to. Gentle activity (short walks, light stretching) can help energy and mood. Cancer Council – Fatigue and Cancer*** (PDF)Practical guide to cancer‑related fatigue: what it is, common causes, and step‑by‑step strategies to pace, stay active safely, and ask for help. *
• Sleep issues / insomnia Sleep issues and insomnia are common in people with metastatic breast cancer. Medicines, pain, anxiety and treatment schedules can all disrupt sleep. Simple sleep‑routine changes, relaxation strategies, or short‑term medicines can help; ask your team what’s right for you.Cancer Council NSW – Sleep problemsQuick tips to improve sleep comfort and routine, plus links to a relaxation and meditation podcast.
• Nausea and vomiting Nausea (feeling sick) and vomiting can be caused by treatments (chemotherapy, some targeted or immunotherapies, and radiation) or by the cancer itself. Your team will usually prescribe anti‑nausea medicines. These work best when taken exactly as directed, even if you feel okay, because it’s easier to prevent nausea than stop it once it starts.Cancer Institute NSW (eviQ)Short, friendly handout on prevention, red‑flag symptoms (fever ≥ 38 °C, dehydration), and practical tips (relaxation, acupressure wristbands).Clinical background: eviQ antiemetic guidelineHow clinicians choose anti‑nausea regimens (risk by drug, breakthrough and anticipatory nausea). Useful if you want to understand the why behind your prescriptions.
• Peripheral neuropathy (tingling, numbness, nerve pain). Physiotherapy or occupational therapy can help with balance and hand/foot care, and your doctor can discuss medications that may ease nerve pain. Cancer Council SA – Peripheral neuropathyEveryday strategies for neuropathy: balance and hand‑foot care, practical aids, when to see physiotherapist or occupational therapist, and how to describe symptoms to your care team.
• Bone health Some treatments and menopause can weaken bones over time. Ask your care team about vitamin D testing, whether calcium/vitamin D supplements are right for you, and weight‑bearing exercise that’s safe. If you have bone metastases, you may be offered bone‑strengthening injections such as denosumab.
• Cognitive changes (“brain fog”) Memory and concentration problems can be common. Use lists, reminders, calendars, and keep tasks short and simple. Tell your care team so that they can check for potentially treatable contributors (e.g., sleep, mood, anaemia, thyroid).Cancer Council – Changes in thinking and memory*** (podcast and PDF)Understand cancer‑related cognitive changes such as attention, memory, word‑finding. Includes practical ways to cope, including sleep, mood and fatigue supports you can try. Includes a podcast on brain fog to listen to anytime.BCNA – Managing cognitive changes** (webcast)Expert webcast with an occupational therapist discussing practical strategies to manage cognitive changes at work and home, and how to advocate for supports.*
• Hair loss and thinning Some treatments cause thinning rather than total hair loss. This is more common with hormone therapy, some targeted therapies and immunotherapy; chemotherapy and radiation can also affect hair depending on the drug, dose and body area treated. If thinning happens, it often improves after treatment ends; regrowth can take a few months and may return with a different texture or curl (sometimes permanently if a scalp area received higher‑dose radiation). If you’re receiving intravenous chemotherapy, ask your team whether scalp cooling (“cold caps”) could be an option to reduce hair loss (it doesn’t suit every drug or diagnosis and isn’t always available).Cancer Council NSW – Understanding Hair LossWhich treatments cause thinning vs loss, everyday hair/scalp care, and when scalp cooling may help.

Pain causes and management

Common causes of pain for people living with MBC

Pain can occur and change at any time. This includes when you are first diagnosis, during treatment, during cancer progression, and at end of life. Common causes include bone metastases, nerve pressure/irritation, treatment‑related effects (e.g., mouth sores, neuropathy), procedures, or muscle/joint strain.

Managing pain

Pain can usually be well managed with the right approach. Pain management options:

• Medication (from paracetamol to stronger opioids)
• Radiation therapy (for bone pain)
• Nerve blocks or other procedures
• Complementary therapies (e.g. massage, acupuncture)

Be honest about any pain you’re experiencing and to get help with pain management early.

Medically induced menopause

Some treatments stop your ovaries working or lead to menopause. Symptoms can include hot flushes, night sweats, vaginal dryness, mood changes and sleep problems.

What can help:

• Non-hormonal medications (ask your doctor what is suitable for you)
• Lifestyle changes (cooling strategies, light layers, gentle exercise, alcohol/caffeine review)
• Vaginal moisturizers for dryness/comfort
• Talking with others who are experiencing the same thing; ask for a referral to a menopause-after-cancer service.

Note: Some hormone‑based treatments or vaginal oestrogen products may not be appropriate for certain subtypes of breast cancer, so it is best to discuss options with your care team. However, various non-hormonal therapies can be used for hot flushes.

Complementary therapies with an evidence base

Some complementary therapies can help with side effects and wellbeing when used alongside your breast cancer treatments.

Evidence-supported options may include:

• Exercise - Helps with fatigue, mood, and overall health
• Mindfulness and meditation - Reduces anxiety and stress
• Acupuncture - May help with nausea and some types of pain
• Massage - Can improve wellbeing and reduce anxiety
• Yoga - Helps with flexibility, strength, and mental health

If you’re unsure about any procedure or compound that is being promoted, speak with your oncologist. You can also use Cancer Council’s online tool to anonymously check and verify any claims you come across.

Looking after your mental health during treatment

Looking after your mental health is important.

In addition to the shock of your diagnosis, treatment can affect mood, energy, and sleep. It’s also common to worry about how well treatment is working. With so much happening, feeling scared or uncertain about the future is normal – and support is available.

Find more information about mental health in Living with MBC.

Disease progression

Signs and what to do

Cancer can change over time. Signs that your cancer may be progressing include:

• New or worsening symptoms (pain, shortness of breath, fatigue)
• Scan results showing growth or new areas of disease
• Blood tests indicating changes to cancer markers
• Treatment side effects becoming harder to manage

What to do:

• Talk to your oncologist about what you’re experiencing
• Report it to your medical team early if you notice significant changes in your body or side effects. While you may have regular scans booked, the earlier progression is detected, the better.

What will happen?

• You’ll likely have additional or more regular scans to assess the situation
• Your treatment plan may be adjusted
• Your medical team may help you to look at clinical trial options
• You may require some additional medical procedures.

Re-biopsy and next-line treatment options

If your cancer progresses, your oncologist may recommend:

Re-biopsy - Taking a new sample of breast cancer cells to test. Sometimes a special blood test called a “Liquid Biopsy” can give this information. Your breast cancer subtype can change over time, new mutations might have developed, and different treatments might now be appropriate. Sometimes new treatments might have been approved where your doctor needs more information about your breast cancer to know if it is appropriate for you.

Next-line treatments - Second-line, third-line (or more) treatments are common. Many people benefit from multiple different treatments over years. New treatments are constantly becoming available. Clinical trials may offer access to newer therapies.

Clinical trials and how to access them

Clinical trials test new treatments that aren’t yet widely available. They may give you access to cutting-edge therapies.

What to know

Trials are carefully monitored for safety, and you can leave a trial at any time.

Costs associated with the drug and scans are usually covered. Sometimes other costs, like travel, are also covered but you need to get advice from the organisation administering the trial about this.

Not everyone is eligible for a trial. Eligibility is based on lots of different factors.

If you come across a trial you think might be an option for you, it’s important to speak to your care team. You can also often contact trials directly.

Different types of trials

Clinical trials are often referred to in phases (Phase I, II and III). This is about how far along in testing on people a drug is.

Early Phase Trials (Phase I/II)

• Are newer treatments with less background knowledge
• May be selected due to particular features of the cancer or its mutations
• Everyone gets the same treatment, but the dose or combination may vary
• Are often designed to understand side effects better before larger trials are done
• Usually require that you have had standard treatment first

Randomised Trials (Phase III)

• Compare a standard treatment to a new treatment or a combination of treatments
• May include a “placebo” if side effects are not expected to be obvious from the new treatment
• May involved supportive care and psychological therapies as well as anticancer treatments

Finding trials

Ask your oncologist if there are trials suitable for you. You can also look for trials at the following sites.

• Australian Cancer Trials (Australian Government website)
• Australian New Zealand Clinical Trials Registry
• Breast Cancer Trials
• ClinTrial Refer
• Clinical Trials (US Government website)