Javier Cortés, MD, PhD, Vall d’Hebron University Hospital, Barcelona, Spain, shares his highlights from the virtual European Society for Medical Oncology (ESMO) Breast Cancer Congress 2021. In particular, Dr Cortés comments on novel data on biomarkers for the prognosis and treatment of patients with breast cancer, including updates on liquid biopsy and discussions around biomarker strategy optimization. This interview took place at the virtual ESMO Breast Cancer Congress 2021