OPTIMA Trial Suggests DNA Test Could Reduce Chemotherapy for Breast Cancer Patients
The OPTIMA trial, presented at ASCO 2026, has revealed that a tumor gene expression test could allow millions of women with breast cancer to avoid unnecessary chemotherapy. Conducted by researchers at University College London and the University of Glasgow, the trial involved over 4,400 women aged 40 or above with newly diagnosed breast cancer across several countries. The genomic testing used Veracyte's Prosigna assay to measure the activity of 50 genes in tumor tissue. Results showed that women with HR-positive, HER2-negative breast cancer, who were identified by the test as unlikely to benefit from chemotherapy, had similar outcomes with hormonal therapy alone. The study found that invasive breast cancer free survival was 91.5% in the control group and 90.4% in those who received only hormonal therapy, meeting the threshold for non-inferiority. 
