1. What is the Prosigna test?
Prosigna is a test that predicts how likely breast cancer is to spread to somewhere else in the body (secondary breast cancer) within 10 years of diagnosis, in people who will be taking hormone therapy for at least 5 years.
2. Who is Prosigna for?
Prosigna may be suitable if you’ve recently been diagnosed with:
- Early stage breast cancer
- That is oestrogen receptor positive
- And HER2 negative
If cancer is in 1 to 3 lymph nodes
If breast cancer has spread to 1 to 3 lymph nodes under the arm, Prosigna may be offered to:
- Women who have been through the menopause
- Men
- Some trans, non-binary or intersex people
If there’s no cancer in the lymph nodes
Prosigna may be offered to help you decide whether to have chemotherapy if:
- Breast cancer has not spread to any lymph nodes, or if a small amount of cancer is in the lymph nodes (micrometastases)
- And you’ve been told you have an intermediate risk of breast cancer spreading to another part of the body
3. Why is it used?
Your specialist may recommend the Prosigna test to help decide if other treatments, particularly chemotherapy, are needed.
Chemotherapy may be given after surgery to reduce the risk of breast cancer coming back in the future.
Whether you’re offered chemotherapy depends on a number of features of your breast cancer. These include:
- The size and grade of the cancer
- Whether it has spread to any of the lymph nodes under the arm
- Whether the cancer is hormone receptor and HER2-positive or negative
For some people the benefit of chemotherapy is clear, but for others it’s less clear.
4. How does it work?
The test is done on a small amount of breast cancer tissue already removed (for example during a or surgery). The tissue is sent to a laboratory in the UK that may be outside your local hospital, where the test is carried out.
The test looks at groups of genes found in breast cancer and features of the breast cancer to produce a score.
The results are given separately from your pathology report and are sent to your specialist usually within 7 days.
If your specialist has recommended you have hormone therapy before surgery, the test must be done on the tissue removed by a core biopsy before you start hormone therapy.
5. Prosigna score
The test gives a Recurrence Score between 0 and 100. Based on this score and whether any lymph nodes under the arm are affected, the results are reported as ‘low’, ‘intermediate’ or ‘high’ risk.
Your specialist will use the score, along with other information about your breast cancer, to help decide what treatment to recommend.
Low risk
A low risk score means it’s unlikely the breast cancer will spread to somewhere else in the body in the next 10 years.
Most people with a low risk score will not need chemotherapy.
People are at low risk if they have:
- A score of 0 to 40 and no breast cancer in any lymph nodes
- A score of 0 to 15 with breast cancer in up to 3 lymph nodes
Intermediate risk
An intermediate risk score means the decision whether to have chemotherapy is less clear.
Your specialist will discuss your test result with you to help decide what to recommend.
People are at intermediate risk if they have:
- A score of 41 to 60 and no breast cancer in any lymph nodes
- A score of 16 to 40 with breast cancer in up to 3 lymph nodes
High risk
A high risk score means it’s more likely the breast cancer will spread to somewhere else in the body in the next 10 years.
Chemotherapy is recommended for most people with a high risk score.
People are at high risk if they have:
- A score of 61 to 100 and no breast cancer in any lymph nodes
- A score of 41 to 100 with breast cancer in up to 3 lymph nodes
6. Availability and cost
If Prosigna is suitable for you, it’s usually available on the NHS across the UK.
Most private healthcare companies will also cover the cost of the test.
You can also pay for the test yourself, but your treatment team will need to order the test for you and will be sent the results to discuss with you. It costs around £1,400.