The application of invisible IHC to augment visible IHC is shown in Figure 7 in which a breast cancer FFPE tissue was stained with HER2 IHC plus hematoxylin counterstain using the common brightfield chromogen, DAB, as well as PD-L1 IHC using the sCy7 chromogen. This evidence concerns the gene ERBB2 and breast carcinoma.