In case of breast cancer, for example, up to 70% of the cells presented with positive immunohistochemical detection for ER and or progesterone receptor, while the other subtypes such as human epidermal growth factor receptor 2 (HER2)-enriched comprises of approximately 12%–20% and triple negative breast cancer (TNBC) cases that presented with 15%–20% in invasive breast cancer (Fragomeni et al., 2018). The gene discussed is ERBB2; the disease is breast cancer.