The prognostic value of AR in ER-negative patients and therapeutic targets for patients absent in AR remains poorly explored.<h4>Methods</h4>We used an RNA-based multigene classifier to identify AR-low and AR-high ER-negative participants in the Carolina Breast Cancer Study (CBCS; N = 669) and The Cancer Genome Atlas (TCGA; N = 237). This evidence concerns the gene ESR1 and breast cancer.