AFP and hepatocellular carcinoma: The individual performance of our four candidates (aspartic acid, glutamic acid, hypoxanthine, and taurine) to identify BCLC 0/A-HCC yielded an ROC–AUC between 80.5% and 90.8%, whereas serum alpha fetoprotein (AFP) alone yielded only an AUC of 77.2% (Table S4).