Here, we detected PD-L1 expression in advanced gastric cancer using IHC in protein level and RNAscope assay in mRNA level, which was an antibody-independent assay for in situ PD-L1 mRNA detection of FFPE sections, using a rationale similar to that used to confirm HER2 amplification [15]. The gene discussed is ERBB2; the disease is gastric cancer.