An international study led by University College London (UCL) has found that many people over 40 with hormone-sensitive breast cancer could safely avoid chemotherapy altogether.
The OPTIMA clinical trial, involving over 4,400 people, showed that a gene test can identify those unlikely to benefit from chemotherapy, meaning they can instead be treated with hormone therapy alone.
Researchers found that patients over 40 with a low Prosigna score – which measures gene activity linked to cancer growth – could skip chemotherapy without increasing the risk of their cancer returning.
Results of the trial, to be presented at the American Society of Clinical Oncology meeting in Chicago, suggest more than two‑thirds of patients fall into this low‑risk category.
After five years, survival rates were nearly identical. Some 94.8 per cent of patients who received chemotherapy alongside hormone therapy remained cancer‑free, compared with 93.6 per cent of those treated with hormone therapy alone.
Researchers said the findings show chemotherapy offers little or no additional benefit for most people in this group, while exposing them to significant side effects.
Chemotherapy is routinely given to patients whose cancer has spread to nearby lymph nodes, reducing the risk of recurrence. But doctors have long suspected that many patients with the most common, hormone‑sensitive form of the disease are being overtreated.
The OPTIMA trial set out to address this by using the Prosigna genomic test, which can be run in NHS laboratories and analyses tumour biology rather than relying solely on clinical factors.
Patients with higher scores still receive chemotherapy, while those with low scores were treated with hormone therapy alone.
Less invasive personalised treatment options
Professor Rob Stein, chief investigator, said the results marked an important shift in more personalised breast cancer treatment.
“OPTIMA addresses a long-standing challenge in breast cancer care: identifying who truly benefits from chemotherapy and who does not,” Professor Stein said.
“Our findings show that many patients can safely avoid chemotherapy without compromising their outcomes.
He added: “For patients, this means many may be spared the physical and emotional burden of chemotherapy and its potential long-term side effects.
Professor Stein said the approach could benefit the NHS, describing it as a more efficient and evidence-based use of resources.
Experts estimate more than 5,000 NHS patients a year could avoid chemotherapy if the test is widely adopted.
Global trial across 4,400 patients
The study followed patients in the UK, Norway, Sweden, Australia, New Zealand and Thailand, making it one of the most comprehensive trials of its kind.
Participants were aged 40 or over and had undergone surgery for hormone-sensitive breast cancer. Most had cancer that had spread to underarm lymph nodes, placing them at higher risk of recurrence.
Standard treatment typically includes chemotherapy followed by hormone therapy for five to ten years.
Patients in the trial were randomly assigned to receive standard treatment, or test-guided treatment based on their Prosigna score.
In total, 68 per cent of participants were classified as low risk. In this group, outcomes were almost the same regardless of whether chemotherapy was given.
Five years after treatment, 94.8 per cent of those who had chemotherapy were cancer-free, compared with 93.6 per cent of those who did not.
Statistical analysis showed that, at most, only 2 per cent of low-risk patients benefit from chemotherapy.
The findings were consistent across subgroups, including pre- and post-menopausal women and patients with varying numbers of affected lymph nodes.
Potential savings for the NHS
Researchers say the results could inform decisions by the National Institute for Health and Care Excellence (NICE) on wider NHS access to Prosigna testing.
The total annual cost of chemotherapy for early breast cancer in the UK is estimated to be £248m when wider societal costs are included, such as lost productivity and patient expenses. Direct NHS costs are estimated at £100m to £120m a year.
Around 55,000 women are diagnosed with breast cancer in the UK each year. About 30 per cent receive chemotherapy (roughly 16,000 to 18,000 patients).
With treatment costing between £5,000 and £8,000 per patient, researchers say reducing unnecessary chemotherapy could lead to substantial savings while improving quality of life.
Chemotherapy side effects
Symptoms can include:
- extreme fatigue not relieved by rest
- nausea and vomiting
- hair loss
- loss of appetite and weight changes
- mouth sores
- increased risk of infection
- “chemo brain” (memory and concentration problems)
- tingling or numbness in hands and feet
- early menopause and fertility problems
