AFP and hepatocellular carcinoma: The stratified results of the validation dataset showed our HCC-specific gene signature was more applicable to the elderly male patients with preoperative relatively lower serum level of CRE (creatinine), AFP (alpha-fetoprotein) and PLT (platelet) and higher serum level of ALB (albumin) (Figure 4B, 4C, 4D, 4E, 4F and 4G).