AFP serves as a diagnostic aid, GPC-3 indicates hepatoid differentiation, while SALL4 is diffusely expressed in hepatoid adenocarcinoma but negative in hepatocellular carcinoma (Chandan et al. 2016; Ushiku et al. 2010), and additionally, Hep-1, another highly specific hepatocyte marker, demonstrates a sensitivity and specificity of 80% and 90%, respectively, making it a reliable indicator for hepatocyte differentiation and hepatocellular carcinoma diagnosis (Xu et al. 2019a). The gene discussed is AFP; the disease is hepatoid adenocarcinoma.