Abstract
HER2-low expression is associated with hormone receptor (HR) expression in HR-positive breast cancer. We aimed to evaluate its association with androgen receptor (AR) among 196 patients with metastatic triple-negative breast cancer (mTNBC). Central determination of AR showed significant enrichment in HER2-low compared with HER2-0 mTNBC (mean: 33.7% vs. 21.4%, p = 0.038), whereas no significant immunological differences were observed. HER2-low/AR-positive patients trended towards longer overall survival, highlighting the potential relevance of these biomarkers.