Stage 4 – Metastatic Breast Cancer

Stage 4 metastatic breast cancer (also known as advanced or secondary breast cancer), is breast cancer which has spread beyond the primary site of the breast. Most commonly, it is found in the bones, liver, lungs and brain, however the cancer may not spread to all of these areas.

The majority of those diagnosed with metastatic breast cancer have been diagnosed with an earlier stage of breast cancer before. It can often lie dormant for many years since their initial diagnosis. However, for some, a diagnosis of secondary breast cancer may be their first diagnosis of cancer.


Advanced breast cancer is considered incurable. Although it has spread to other parts of the body, it is considered and treated as breast cancer. For example, breast cancer that has spread to the bones is still breast cancer (not bone cancer) and is treated with breast cancer drugs. The aim of treatment is to control the growth and spread of the cancer, to relieve symptoms, reduce pain, improve or maintain quality of life, and help patients live longer.

Treatment options can include surgery, radiation, chemotherapy, hormonal therapy and/ or targeted therapy, depending on the location and subtype of the cancer. If the cancer is hormone receptor-positive, the first treatment is hormone therapy. If the cancer is HER2-positive, patients may be prescribed anti-HER2 drugs such as trastuzumab (Herceptin). Chemotherapy, surgery and/ or radiation therapy can be used to shrink or slow the growth of tumours or to ease symptoms.