AFP and hepatocellular carcinoma: According to the well-established 400 ng/ml cut-off,2 only 12% (29/244) of patients with early HCC presented high serum levels of AFP, which was accompanied by aberrant overexpression of the gene in the tumour (FC = 40; p < 0.001) compared with the adjacent non-tumoral tissue (Supplementary Fig. 2B).