New DNA test could allow millions of breast cancer patients to safely avoid chemotherapy

A significant international clinical trial, known as OPTIMA, has revealed that many breast cancer patients could safely forgo chemotherapy, leading to improved quality of life and reduced side effects. The study, led by University College London, utilized a genomic test called Prosigna to analyze gene activity in tumor samples, helping to identify patients who would not benefit from chemotherapy. The Prosigna test assists in determining the risk of cancer recurrence, enabling a more personalized treatment approach.

The findings indicate that individuals aged 40 and older with hormone-sensitive breast cancer and a low Prosigna score can be effectively treated with hormone therapy alone, bypassing the need for aggressive chemotherapy. This breakthrough, which involved over 4,400 patients across multiple countries, is set to be presented at the 2026 American Society of Clinical Oncology (ASCO) meeting, marking a pivotal step towards tailoring cancer treatments based on individual tumor biology.