1.Hepatocellular carcinoma One of the common causes of high alpha-fetoprotein is that the content of alpha-fetoprotein in normal human serum is less than 20μg/L, but when hepatocellular carcinoma occurs, the function of producing this protein is restored. AFP is usually elevated 8 months before the symptoms of liver cancer appear, so people with cirrhosis, chronic hepatitis patients, and those with liver cancer in their family should have regular checkups according to their condition. Therefore, methemoglobin has certain significance for the early diagnosis of liver cancer. 2.Pregnant women and newborns may also have a momentary elevation of AFP because AFP is a normal plasma protein component of the fetus and is the main protein of the early embryo. AFP in pregnant women is significantly elevated, generally in the third month after pregnancy, AFP rises significantly, and the amount of AFP in maternal blood of pregnant women reaches its peak and is relatively stable in July-August, but it is still below 400μg/L The AFP level gradually returns to normal after about 3 weeks after delivery. 3.Non-malignant diseases High AFP may be associated with non-malignant diseases such as acute and chronic hepatitis, recovery from severe hepatitis, cirrhosis, congenital bile duct occlusion, malformed fetus, etc. AFP may be elevated, but the magnitude of elevation is relatively small and the duration is relatively short. According to the data, about 50% of patients with germ cell tumors have positive AFP; some patients with other gastrointestinal tumors such as pancreatic cancer or lung cancer and liver cirrhosis may also have high AFP to varying degrees; in addition, male patients with AFP greater than 25μg/L should also consider testicular cancer. In addition, male patients with AFP greater than 25μg/L should consider the possibility of testicular cancer. 5.Viral hepatitis Mild or moderate elevation of alpha-fetoprotein in chronic hepatitis active stage, usually from 50 to 300μg/L. The difference with hepatocellular carcinoma is that the elevation is low and usually does not increase continuously, and it will decrease or return to normal after treatment. 6.Neonatal hepatitis 30% of neonatal hepatitis can be measured with alpha-fetoprotein, the incidence of which increases with the severity of the disease and is mostly significantly higher. This can be distinguished from congenital bile duct atresia, in which alpha-fetoprotein is mostly normal. 7. Other causes Liver injury, congestive hepatomegaly, ataxia, capillary dilation, congenital tyrosinosis, pregnant women (3-6 months), and embryonal tumors of the testes or ovaries (such as seminoma, malignant teratoma, ovarian cancer, etc.) also often have elevated AFP.