For this purpose, we identified the profiles of expression of routinely used biomarkers (ER, PR, HER2, and Ki-67) and other proteins that play potential roles in BC carcinogenesis (Bcl-2, cyclin D1, E-cadherin, Snail and Slug, GCDFP-15, PD-L1, and PRL-3) in the PTs and paired ALN metastases to demonstrate that such assessment may be insufficient to the potential detriment of the patients. The gene discussed is ESR1; the disease is breast cancer.