Is the alpha-fetoprotein level in liver cancer always high? Not necessarily high

Does liver cancer always have high alpha-fetoprotein? Alpha-fetoprotein is a marker that plays a significant role in clinical disease diagnosis. It is closely related to the occurrence and development of liver cancer and various tumors. It can be found in high concentrations in various tumors and can be used as a positive indicator for tumor detection. So, does liver cancer always have high alpha-fetoprotein?

Alpha-fetoprotein (AFP) is a glycoprotein. Under normal circumstances, this protein mainly comes from the liver cells of the embryo. About two weeks after the fetus is born, AFP disappears from the serum. The AFP content in the serum of a normal adult is less than 20 micrograms/liter.

Since alpha-fetoprotein is secreted by newborn liver cells, the liver cells of the fetus have not fully developed (differentiated), and the amount of alpha-fetoprotein secreted is very large, so the alpha-fetoprotein level of pregnant women will increase. Similarly, liver cancer cells are primitive cells that have not yet differentiated, that is, the most immature liver cells, so they can secrete a large amount of alpha-fetoprotein.

AFP is a specific marker for liver cancer, but elevated serum AFP does not necessarily indicate liver cancer. In more severe chronic hepatitis or cirrhosis, many liver cells are destroyed and replaced by extensive fibrous tissue. When there is active inflammatory necrosis, liver cells must be regenerated quickly, and a large number of newly regenerated liver cells will secrete AFP. Therefore, in patients with hepatitis and cirrhosis, elevated AFP only indicates that the disease is more severe.

Experts analyzed the alpha-fetoprotein levels of a group of patients: 20.0% of 290 chronic hepatitis patients had elevated levels, mainly moderate to severe hepatitis; 45.5% of 201 patients with compensated cirrhosis had elevated levels; and 72.3% of 224 patients with decompensated cirrhosis had elevated levels. The more severe the liver disease, the more elevated the alpha-fetoprotein level, and the greater the magnitude of the increase.

Similarly, alpha-fetoprotein levels in patients with liver cancer may not necessarily be elevated. A small number of patients with liver cancer may have normal alpha-fetoprotein levels, perhaps because the liver cancer is very small and the production is low, or although the tumor is large, the secretion is delayed, so normal alpha-fetoprotein levels do not mean that there is no liver cancer.