Gene expression associated with endocrine therapy resistance in estrogen receptor-positive breast cancer

Gene expression analysis to study early-stage estrogen receptor-positive breast cancer patient associated with endocrine therapy resistance. Breast cancer primary cancer patients were treated with endocrine therapy, including selective estrogen receptor modulators (SERMs), selective estrogen receptor degraders (SERDs), and aromatase inhibitors (AI) with both locoregional and distant recurrences with IRB approval were selected for this study. Surgical pathology archives were queried for HER2- ER+BC formalin-fixed paraffin-embedded (FFPE) specimens resected with a ER+ more than 10% as cutoff. mRNAseq gene expression analysis for 48 patient by exploring recurrent vs non-recurrent (NR) groups using a nCounter® Custom CodeSet by NanoString.