LONDON, UNITED KINGDOM: A breast cancer gene test could help thousands of eligible patients avoid chemotherapy and save the UK’s National Health Service (NHS) around £4 million a year, according to new economic analysis.
The Prosigna test uses information from tumor genes to help doctors assess the risk of cancer returning. Findings from the international OPTIMA trial suggest that some patients may receive little additional benefit from chemotherapy when their tumors has a low genomic risk score.
How Prosigna Could Change Breast Cancer Treatment
The findings address a major challenge in breast cancer care: identifying patients who are likely to benefit from chemotherapy and those who may achieve similar outcomes with other treatments.
Chemotherapy can reduce the risk of breast cancer returning. However, its benefits vary between patients. Some people may experience significant side effects without gaining enough additional benefit to justify the treatment.
The OPTIMA trial, led by University College London (UCL), investigated whether a genomic test could help doctors make more personalized treatment decisions. The research involved 4,429 people aged 40 and older with selected types of early-stage breast cancer.
An economic analysis published by UCL on 25 October 2026 estimates that wider use of the test could save the NHS approximately £4 million annually. The potential savings come from reducing chemotherapy use in patients identified as unlikely to gain meaningful additional benefit.
What the OPTIMA Trial Found
The phase III OPTIMA trial enrolled patients with clinically high-risk, oestrogen receptor-positive (ER-positive), HER2-negative early breast cancer. Participants were randomly assigned to standard chemotherapy followed by hormone therapy or a treatment strategy guided by their Prosigna results.
In the test-directed group, patients with a high risk-of-recurrence score received chemotherapy and hormone therapy. Those with a low score received hormone therapy without chemotherapy.
Other treatments, including radiotherapy where indicated, continued according to clinical requirements.
The trial reported the following estimated five-year outcomes:
| Trial population | Standard chemotherapy and hormone therapy | Test-directed treatment |
|---|---|---|
| All patients in the per-protocol analysis | 91.8% | 90.3% |
| Patients with a low genomic risk score | 94.8% | 93.6% |
These figures represent invasive breast cancer-free survival. The analysis found that test-directed treatment met the trial’s predefined non-inferiority criteria.
In simple terms, the results did not show a decline beyond the limit researchers had agreed would be clinically acceptable. The median follow-up was approximately four years, so longer-term evidence remains important.
For patients with a low score, the findings suggest that chemotherapy may offer limited additional benefit. They do not mean that every patient with a low score will have the same outcome or that chemotherapy is unnecessary for all people with breast cancer.
How the Prosigna Gene Test Works
Prosigna is a genomic tumor-profiling test. It examines the activity of 50 genes involved in breast cancer growth using a sample of tumor tissue obtained during surgery or, where suitable, a diagnostic biopsy.
The test produces a risk-of-recurrence score that helps doctors estimate the likelihood of cancer returning. It also provides information about the tumor’s biological characteristics.
The OPTIMA trial used a score threshold of 60 to guide treatment decisions:
- Low score, 60 or below: Patients received hormone therapy without chemotherapy in the test-directed group.
- High score, above 60: Patients received chemotherapy alongside hormone therapy.
The test does not examine inherited BRCA1 or BRCA2 mutations. Instead, it measures gene activity within the tumor to help guide decisions about treatment after surgery.
According to Cancer Research UK, tumor profiling tests can help doctors estimate recurrence risk and determine whether additional chemotherapy may be appropriate. These tests are not suitable for every patient, and results must be interpreted alongside other clinical information.
How the Test Could Save NHS £4m
The projected savings come from an economic analysis of the OPTIMA trial presented at the European Society for Medical Oncology Congress in October 2026.
The analysis estimated that around 6,159 patients a year could be eligible for testing under the study’s assumptions. Approximately 67% of patients in the relevant trial population had low genomic risk scores. Across the UK, this could mean around 4,200 people a year avoiding chemotherapy if testing were used more widely.
The economic model considered several costs:
- Chemotherapy: Approximately £5,500 per patient receiving standard chemotherapy, including drugs, clinical staff time, medicines for side effects and hospital admissions.
- Prosigna testing: Approximately £1,955 per patient at the reported NHS list price.
- Estimated net saving: Around £654 per patient tested over the first two years after diagnosis.
Applying the estimated £654 saving to 6,159 patients produces an annual projection of approximately £4.03 million. A Daily Mail report on the findings also highlighted the potential £4 million annual saving, based on the analysis.
The projection is not a confirmed reduction in NHS spending. Actual savings would depend on testing costs, eligibility, clinical decisions and wider adoption.
UCL also noted that the initial economic analysis covered approximately the first two years after diagnosis, with longer-term costs still to be assessed.
Why Avoiding Chemotherapy Matters
Chemotherapy can be essential for treating breast cancer, but it can also affect healthy cells and cause difficult side effects.
Common effects include fatigue, nausea, vomiting, temporary hair loss, mouth sores and a weakened immune system that increases the risk of infection. Some patients also experience nerve problems, fertility issues or side effects that last beyond treatment.
The severity depends on the medicines used, the dose and the individual patient’s response. Some side effects improve after treatment ends, while others may persist or appear later. The NHS chemotherapy guidance explains these risks and the need for personalized treatment advice.
Avoiding chemotherapy when it is unlikely to provide meaningful additional benefit could reduce treatment-related discomfort, the need for supportive care and the time spent attending hospital appointments.
However, avoiding chemotherapy is beneficial only when the decision is appropriate for the patient’s cancer and overall health. Patients should not stop or refuse prescribed treatment based on a genomic test result without discussing it with their cancer specialist.
Who Could Benefit From Testing?
The OPTIMA findings are relevant to selected patients aged 40 and older with early-stage, ER-positive, HER2-negative breast cancer. The trial included people with up to nine affected lymph nodes and patients with larger tumors, making its findings important for some patients with higher clinical risk.
However, trial evidence and current NHS access rules are not the same thing. UCL’s October 2026 report stated that NHS approval for Prosigna remained restricted by menopausal status and lymph node involvement. In England, Wales and Northern Ireland, the reported approval applied to postmenopausal women whose cancer had spread to no more than three lymph nodes. In Scotland, the reported restriction was to postmenopausal women whose cancer had not spread to any lymph nodes.
The broader OPTIMA findings may inform future treatment guidance, but they do not automatically make testing available or appropriate for every patient represented in the trial.
Doctors must consider tumour characteristics, the patient’s age and menopausal status, lymph node involvement, recurrence risk, other health conditions and the potential benefits and risks of each treatment option.
Patients should ask their oncology team whether genomic testing is available and appropriate for their diagnosis. Treatment decisions should also reflect the patient’s preferences and understanding of the expected benefits.
What Happens Next?
The potential clinical and financial benefits have increased interest in using genomic tests to guide chemotherapy decisions.
Further follow-up will help researchers understand whether the results remain consistent over a longer period and whether the projected savings hold up in routine care.
The OPTIMA trial was sponsored by UCL and received more than £5.7 million in grants from the National Institute for Health and Care Research. Veracyte, the company that makes Prosigna, provided approximately £1.8 million in additional funding and testing support. Reporting this funding helps readers assess the research transparently.
The next challenge is to determine how the evidence should inform clinical guidance, testing access and treatment decisions across the NHS.
Conclusion
The Prosigna breast cancer test could help thousands of eligible patients avoid chemotherapy when their tumour’s genomic profile suggests limited additional benefit.
The OPTIMA trial found comparable five-year invasive breast cancer-free survival estimates among patients with low genomic risk scores who received test-directed treatment and those who received standard chemotherapy alongside hormone therapy.
Economic modelling suggests that wider testing could save the NHS around £4 million a year. However, the estimate depends on broader use of the test and is not a guarantee of future savings.
Longer-term follow-up and individual clinical assessment remain essential to ensure that patients receive the treatment most likely to benefit them.
