In this study we found a significantly decreased frequency of 100TT-related genotypes with decreased susceptibility to HCC, consistent with previous studies that reported that CYP2D6 poor metabolizer (PM) genotypes or inactivating alleles were significantly more frequent in healthy subjects and carriers than in patients with hepatitis/cirrhosis and HCC [18, 19]. This evidence concerns the gene CYP2D6 and hepatocellular carcinoma.