A large-scale multicenter study, published in Lancet Oncology, has shown that DKK1 is overexpressed in HCC and that the levels of DKK1 in serum can be used in addition to AFP levels to improve the screening of AFP-negative HCCs and to distinguish them from nonmalignant chronic liver diseases; however, more studies are needed before DKK1 can be accepted as a diagnostic tool for HCC [16,25]. This evidence concerns the gene AFP and hepatocellular carcinoma.