Alpha-Fetoprotein

Positive staining with anti-AFP is seen in hepatocytes of fetal liver and hepatoma. Since only traces of AFP are found in adult serum, elevated levels suggest either a benign or malignant lesion of the liver, a yolk sac carcinoma, or one of a few other tumors. Correspondingly, in conjunction with elevated serum levels, AFP has been immunohistochemically demonstrated in yolk sac tumor of gonadal and extragonadal sites, in hepatic malignancies, and a few other neoplasms. The antigen is not denatured by most fixatives.