Alpha-fetoprotein (AFP) is a fetal tumor-associated polypeptide of the albuminoid gene family that binds and transports molecules in addition to several other putative roles. The fetal liver is the primary site of synthesis for this secretory protein, while the adult liver represses its expression. Anti-AFP has been immunohistochemically demonstrated in hepatocellular carcinoma (HCC) and displays no immunoreactivity in normal liver.