The conventional diagnosis of breast cancer involves histological analysis using hematoxylin and eosin (H&E) staining followed by immunohistochemical analysis for key biomarkers, namely, estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) staining for morphometric analysis from permanent tissue sections4. The gene discussed is ERBB2; the disease is breast cancer.