The hepatocytic markers used in clinical practice include IHC for HepPar-1, Arg-1, GPC3, and AFP, and the positive rates for these proteins in HCC are reported at 70–85, 45–95, 60–90, and 30%, respectively.27,28 Although AFP RNAscope when used purely as a marker of hepatocytic differentiation is much less sensitive compared to HepPar-1 and Arg-1, its 100% specificity indicates this method has a significant advantage over other markers. The gene discussed is GPC3; the disease is hepatocellular carcinoma.