Normal Value and Significance of Alpha-Fetoprotein

Under normal circumstances, the reference range for alpha-fetoprotein (AFP) is 0–20 ng/mL. For healthy adults, slight variations within the normal range are generally not of significant clinical importance. However, in certain conditions such as pregnancy, hepatocellular carcinoma, choriocarcinoma, ovarian cancer, and testicular cancer, levels of alpha-fetoprotein may increase. A detailed analysis is as follows:

1. Normal Values

The normal value of alpha-fetoprotein can vary depending on age, sex, and disease status. Generally, the normal range for adults is 0–20 ng/mL, while infants and children may have slightly higher levels. For pregnant women, the normal range of alpha-fetoprotein varies according to gestational age, fetal position, and other factors. In tumor-related examinations, such as for liver cancer, the normal reference values for alpha-fetoprotein may also differ. Therefore, when interpreting alpha-fetoprotein test results, it is essential to consider the clinician's diagnosis and integrate it with other clinical findings.

2. Clinical Significance

In pregnant women, alpha-fetoprotein levels can be measured through prenatal screening tests to assess the risk of fetal neural tube defects. Elevated levels of alpha-fetoprotein may indicate malignant diseases such as liver cancer, pancreatic cancer, or benign liver tumors, making it a useful tumor marker. The alpha-fetoprotein level can also be used to monitor treatment response in chronic liver conditions such as cirrhosis, hepatitis B, and hepatitis C. Low levels of alpha-fetoprotein may suggest an increased risk of certain liver diseases, including autoimmune hepatitis and cirrhosis.

If significantly abnormal alpha-fetoprotein levels are detected, it is recommended to undergo further detailed evaluation under a physician’s guidance to establish a definitive diagnosis and initiate appropriate treatment.