Robert C. Stein, PhD FRCP; ASCO 2026: Gene Test Finds Most Patients with High Risk ER-positive, HER2-negative Early Breast Cancer Do Not Benefit from Chemotherapy

The idea that all women with hormone dependent early breast cancers that test negative for the HER2 molecule and have high risk clinical factors should be receive chemotherapy in addition to endocrine therapy is now being strongly questioned. A new study using a gene expression test to predict recurrence risk has shown that most patients do not benefit from adding chemotherapy to their ongoing endocrine treatment. Results from the OPTIMA phase III randomized non-inferiority trial reported at the 2026 annual meeting of the American Society of Clinical Oncology suggest that the current standard of care recommending chemotherapy for high-risk groups needs to be changed. Peter Goodwin got the details of the study findings from first author, Robert C. Stein, PhD FRCP, Professor of Breast Oncology at University College, in London.