The severity of breast cancer is described by five stages, depending on tumour size and location. Stage 0 means pre-cancerous cells are present in the breast (e.g. carcinoma in situ). Stage 1 means there is a small tumour in the breast, but no lymph node involvement (this is called invasive cancer). Stages 2 and 3 mean either that the tumour is larger or that there are some cancer cells in the lymph nodes of the armpit or other nearby tissues, such as the skin. Stage 4 means the cancer has spread to form tumours (metastases) in other, distant parts of the body. Severity increases with stage and consequently treatment options vary between stages.


If you have been diagnosed with stage 3 breast cancer, should you have staging examinations?

Yes, for women with suspected clinical stage 3 breast cancer without symptoms of metastases, the ECIBC's Guidelines Development Group (GDG) recommends using staging exams with conventional imaging techniques. However, if positron emission tomography-computed tomography (PET-CT) is available, the GDG suggests using PET-CT alone.

Who is this recommendation for?

  • You have been diagnosed with breast cancer
  • You do not have symptoms that suggest potential metastases
  • You may have been told by your healthcare professional that it could be stage 3 breast cancer

What would following this recommendation mean for you?

It might be important to speak with your healthcare professional about the different clinical stages of breast cancer and whether you have symptoms of metastases.

You may also wish to speak with your healthcare professional about:

  • risk of the cancer developing or spreading to other parts of the body
  • treatment for stage 3 breast cancer
  • anxiety and distress.

Additional considerations

Having staging examinations with conventional imaging techniques is likely to find more metastases. It is also likely to result in a large increase in false positive results, which means a woman would have further tests, including biopsy. These tests will confirm that she does not have metastases, but may have suffered unnecessary anxiety and distress.

However, the GDG judged that, for women with suspected clinical stage 3, the benefits are greater than the harms.

Using PET-CT examinations probably results in more women being correctly staged, which is helpful in deciding on their treatment plans, and it may reduce the risk of receiving a false positive result, but the evidence is very uncertain for this last effect.

The GDG noted that the costs would be higher when staging examinations with PET-CT are provided.


Metastasis refers to the spread of cancer cells from the place where they first formed to another part of the body.

Biopsy: a sample of tissue to be taken from your breast or elsewhere, to test for cancer.

Positron emission tomography-computed tomography is a medical procedure that uses radioactive substances to measure biological processes.

Documentation for professionals