Stage 4 breast cancer

The stage of a cancer tells you how big it is and whether it has spread. It helps your doctor decide which treatment you need.

Stage 4 breast cancer has spread to another part of the body. It is also called advanced cancer or secondary breast cancer. The aim of treatment is to control the cancer and any symptoms. Treatment depends on a number of factors.

There are different systems used in the UK to stage breast cancer. Stage 4 is part of the number staging system. Doctors may also use the TNM staging system.  

Staging for breast cancer is very complex. Many different factors are considered before doctors can confirm your final stage. Speak to your doctor or breast cancer nurse specialist if you have any questions about your staging. Below is a simplified description of stage 4 breast cancer. 

In stage 4 breast cancer:

  • the cancer can be any size
  • the lymph nodes Open a glossary item may or may not contain cancer cells
  • the cancer has spread (metastasised) to other parts of the body such as the bones, lungs, liver or brain
Diagram showing M stages breast

TNM stages

The TNM staging system stands for Tumour, Node, Metastasis.

  • T describes the size of the tumour (cancer)
  • N describes whether there are any cancer cells in the lymph nodes
  • M describes whether the cancer has spread to a different part of the body

In the TNM staging system, stage 4 breast cancer is the same as:

  • Any T Any N M1


Your doctor will take many different factors into account when deciding which treatment is best for you. These include:

  • the type of cells the cancer started in
  • which part of your body the cancer has spread to
  • the treatment you have already had
  • your general health
  • whether you have had the menopause Open a glossary item
  • whether the cancer is growing slowly or more quickly
  • whether the cancer cells have receptors for particular cancer drugs

Secondary breast cancer may respond to several types of treatment. Doctors usually start with treatment that has as few side effects as possible.

Stage 4 breast cancer is unlikely to be cured. But treatment can often keep the cancer under control for many months or years.

Hormone therapy

Hormone therapy is a common treatment for secondary breast cancer. It can often shrink and control the cancer wherever it is in the body. It works well if the cancer cells have particular proteins called hormone receptors.

If one hormone therapy stops working so well, your doctor might suggest you try a different one.


Your doctor might suggest chemotherapy if your cancer doesn't have hormone receptors or has spread to the liver or lungs.

Targeted and immunotherapy drugs

There are different types of targeted and immunotherapy drugs for secondary breast cancer. They include trastuzumab (Herceptin) and palbociclib. 


You might have radiotherapy if the cancer has spread to the bones or the skin near the breast. 

Other treatments you might have

You may have other treatments too. These include:

  • drugs that strengthen the bones called bisphosphonates 
  • medicines to control symptoms that the cancer causes
  • surgery to help to relieve symptoms

Other stages of breast cancer

  • AJCC Cancer Staging Manual (8th edition)
    American Joint Committee on Cancer
    Springer, 2017

  • TNM Classification of Malignant Tumours (8th edition)
    Union for International Cancer Control
    J Brierley, M Gospodarowicz and C Wittekind   
    Wiley Blackwell, 2017

  • Advanced breast cancer: diagnosis and treatment
    National Institute for Health and Care Excellence, 2009. Last updated August 2017

  • ESMO clinical practice guidelines for the diagnosis, staging and treatment of patients with metastatic breast cancer
    A Gennari and others
    Annals of Oncology, 2021. Vol 32, Issue 12. Pages 1475-1495

  • Cancer: Principles and Practice of Oncology (12th edition)
    VT DeVita, TS Lawrence, SA Rosenberg
    Wolters Kluwer, 2023

  • The information on this page is based on literature searches and specialist checking. We used many references and there are too many to list here. Please contact with details of the particular issue you are interested in if you need additional references for this information.

Last reviewed: 
06 Jun 2023
Next review due: 
06 Jun 2026

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