Researchers at University College London (UCL) have identified a way to potentially spare millions of breast cancer patients from the side effects of chemotherapy. By utilizing the Prosigna gene test, clinicians can now identify which patients can safely rely on hormone therapy alone.

A multi-national trial of 4,400 patients

The study tracked more than 4,400 individuals aged 40 and older across a diverse geographic range,including the United Kingdom, Norway, Sweden, Australia, New Zealand, and Thailand. As reported by the source, the trial was specifically designed to see if using the Prosigna test would lead to an increase in cancer recurrence or death within a five-year window.

The Prosigna test functions by analyzing the expression levels of 50 specific genes within a tumor sample. This process allows doctors to classify the cancer into low, intermediate, or high risk of recurrence, providing a much more granular view of the tumor's biology than previous methods. By focusing on these genetic markers, the test offers a way to move away from the "one-size-fits-all" approach that has historically characterized breast cancer treatment.

Shifting from tumor size to 50-gene biological profiles

Traditionally, clinicians have relied on clinical features like tumor size or lymph node involvement to decide if a patient needs chemotherapy.. however, Professor Rob Stein, a professor of breast oncology at the UCL Cancer Institute, noted that these results allow for a shift toward personalized treatment based on actual tumor biology.

This biological approach aims to reduce the "physical and emotional ordeal" of chemotherapy, which can cause fatigue, nausea, and hair loss. By using the Prosigna risk score, clinicians can identify the two-thirds of patients who can safely bypass chemotherapy without compromising their five-year survival rates.

The potential relief for 5,000 NHS patients annually

The clinical implications for the United Kingdom's healthcare system are substantial. According to the report, UCL estimates that more than 5,000 NHS patients could avoid chemotherapy every year if this testing becomes a standard part of the treatment landscape. This shift could also represent a more efficient use of resources,as chemotherapy is both expensive and time-consuming for health systems to administer.

For patients, the avoidance of chemotherapy means dodging significant side effects, including fatigue , nausea, and hair loss, as well as potential long-term heart problems or cognitive issues. For patients like Karen Bonham, a 64-year-old speech therapist from Cardiff, the test provided life-altering news. After being diagnosed in 2017, Bonham had prepared for the harsh side effects of chemotherapy, only to learn she could rely on radiotherapy and hormone therapy instead. Her experience highlights the immense emotional relief that comes with avoiding unnecessary, aggressive treatments.

The unanswered question for pre-menopausal women

While the results are promising for older populations, the study leaves a critical gap regarding younger patients. Because the trial focused on participants aged 40 and over, it remains unverified whether these same findings apply to women under the age of 40.

The next phase of the trial is expected to investigate the use of the Prosigna test for pre-menopausal women. However, the source notes that the resuts of this specific research are still several years away, leaving a period of uncertainty for younger patients seeking to avoid chemotherapy.