Breast cancer (BC) is the most frequently diagnosed cancer worldwide; with 2.3 million new cases in 2020, this accounts for 1 in 8 cancer diagnoses.[1] It is a highly heterogeneous disease that can be caused by a variety of distinct genetic alterations in mammary epithelial cells, requiring a combinatorial evaluation of the histopathology of the primary tumor and of the expression pattern of hormone receptors to determine the optimal patient treatment plan. This evidence concerns the gene NR4A1 and breast cancer.