Benefits of chemotherapy for primary breast cancer

If you have primary breast cancer, whether you’re offered chemotherapy will depend on: 

• The size, stage and grade of your breast cancer
• The oestrogen receptor and HER2 status
• Whether you have an inherited altered gene that increases breast cancer risk, such as BRCA1

Our information on pathology results explains these in more detail.

Your treatment team will also consider your general health and any other medical conditions you have.

The benefits of chemotherapy might be clear for some people but less clear for others.

Your cancer specialist (oncologist) may use an online program to help estimate the benefit you might expect to get from chemotherapy. They may be able to show you a graph of this information or explain the benefit as a percentage.

Genomic assays (also called gene expression profiling or gene assays)

When the benefit of chemotherapy is less certain, your treatment team may suggest tests called genomic assays.

These tests look at groups of genes found in breast cancer cells. They help identify who is most likely to benefit from chemotherapy and how likely the cancer is to come back (recurrence).

The tests are carried out on breast tissue removed during surgery or during the original biopsy on your breast.

The results are provided separately from your pathology report. Your treatment team will consider them alongside your other pathology results to help them decide what treatments to recommend.

Genomic assays are not suitable for everyone. If any of these tests are suitable for you, your treatment team will discuss this with you.

Genomic assays you may be offered are:

Your treatment team may ask you if you want to have chemotherapy. It’s a personal decision and you’ll need to weigh up the likely benefits against potential side effects.

You can talk this through with your treatment team. They can answer your questions and support you with your decision. You can also speak to us on our free helpline – see below.