As shown by Zhang and colleagues, looking at 774 BC patients that had their HER2 status determined by IHC, ISH and targeted genomic profiling of cancer related genes, at the cut-off of a copy number of 2.62, NGS could identify a IHC/ISH-determined HER2-negative status with 97.8% specificity, and at the cut-off of ≥3.62, it could identify a IHC/ISH-determined HER2-positive status with 99.8% specificity, respectively. This evidence concerns the gene ERBB2 and breast cancer.