The number of biological tumoral markers used in the diagnosis and therapy monitoring of hepatocellular carcinoma has increased, but their separate use is limited as none of them is specific, being only tumour-associated (proteins). But when in abnormal amounts and used in combination, they are of great help in the diagnosis and therapy monitoring. A combination of alpha-fetoprotein (AFP) and alpha 1-antitrypsin (AAT) data raises the diagnostic accuracy in hepatocellular carcinoma from 43% obtained with AFP alone, to 90.5% and if the combination includes the carcinoembryonic antigen (CEA) data too the accuracy increases to 100%, still without strict specificity for hepatocellular carcinoma.