Finally, we did not observe a difference in the pattern of syndecan-1 expression according to BC intrinsic subtypes; however, metastatic lesions both TN and with HER2 overexpression (with or without hormone receptor expression) showed a more diffuse pattern of immunostaining, with moderate to strong intensity, compared to their Luminal A-like and Luminal B-like (HER2 negative) counterparts. This evidence concerns the gene NR4A1 and breast cancer.