Abnormal alpha-fetoprotein

Alpha-fetoprotein (AFP): Alpha-fetoprotein is a special protein—a glycoprotein—produced by fetal liver cells. It is a normal component of fetal serum. Clinically, it has been found that liver cancer cells can synthesize alpha-fetoprotein. Therefore, in the serum of patients with primary liver cancer, alpha-fetoprotein is significantly elevated. Recently, radioimmunoassay (RIA) has been commonly used for quantitative determination of alpha-fetoprotein, with a positive rate of about 90% for liver cancer. When hepatocellular carcinoma, testicular tumors in children, or ovarian teratomas in women occur, AFP begins to be produced again and appears in the blood. AFP increases in primary liver cancer or embryonal carcinoma, so testing the AFP level in the blood is of great significance for the detection and diagnosis of such diseases. Its clinical significance is as follows: Elevated alpha-fetoprotein is commonly seen in: (1) Primary liver cancer (except hepatobiliary cell carcinoma), with quantitative tests often greater than 400 ng/ml. (2) Chronic hepatitis and liver cirrhosis, usually below 300 ng/ml. (3) Liver metastasis from other tumors. (4) Normal pregnancy may show elevation from 12 to 38 weeks, usually within 40–540 ng/ml. (5) Occasional elevation after acute blood loss.