NRG-BR008/HERO study: a Phase III randomized trial of radiotherapy optimization for low-risk HER2-positive breast cancer

HER2-positive breast cancer historically had the highest rates of recurrence but has substantially improved outcomes with the advent of targeted anti-HER2 therapies. NRG-BR008/HERO is a Phase III randomized trial evaluating whether adjuvant radiotherapy remains beneficial in low-risk HER2-positive breast cancer treated with HER2-targeted therapies. Patients are randomly assigned to receive either standard radiotherapy or observation after breast-conserving surgery. The primary endpoint is a recurrence-free interval, with secondary endpoints including 7-year ipsilateral breast recurrence, disease-free survival, overall survival, and patient-reported outcomes including worry and breast pain. Clinical Trial Registration: NCT05705401 (ClinicalTrials.gov).