They suggested that the elevated serum HGF is probably produced by infiltrating mesenchymal and cancer cells based on their observations; in one patient whose HGF level was below the detection limit at the initial examination, the concentrations increased over the time and exceeded 0.4 ng/mL just before HCC was detected; HGF concentrations were higher in patients with diffuse carcinomas or with multiple cancers than in patients with a single cancer [28]. This evidence concerns the gene HGF and cancer.