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What is alpha-fetoprotein?
Alpha-fetoprotein (AFP), the full name of "alpha-fetoglobulin", is a glycoprotein. It has a half-life of 5-7 days and belongs to the albumin family. AFP was first discovered in fetal serum in 1956, its normal** was found to be mainly yolk sac and fetal liver in 1963, and high concentrations of AFP were found in patients with primary liver cancer in 1964.
How do I check it and how much does it cost?
1. By drawing venous blood for examination, there is no need to fasting during the examination.
2. Cost: tens to more than 100.
3. The reference value of the examination results is 0-10 ng ml, and there is also a reference value of AFP 20 g L, but the standards will be different in different hospitals.
4. If you have a family history of liver cancer and a history of liver cirrhosis, it is recommended to recheck alpha-fetoprotein regularly.
What are the possible causes of an increase in alpha-fetoprotein AFP?
1. Pregnancy: alpha-fetoprotein AFP can be produced by the liver and yolk sac of the fetus, so during pregnancy, alpha-fetoprotein will be elevated.
2. Primary hepatocellular carcinoma:
Elevated AFP is one of the important indicators of primary liver cancer, with high sensitivity and specificity. Serum elevation in 80% of patients with HCC, and serum AFP >400 g L can be used as the diagnostic threshold for primary HCC. Of course, a normal AFP cannot completely rule out liver cancer, and it also needs to be combined with imaging examinations such as color ultrasound, CT, and MRI.
3. Gastric cancer: AFP-positive gastric cancer, hepatic adenocarcinoma. The current definition of AFP-positive gastric cancer is serum AFP >25 ng ml or immunohistochemistry suggests AFP-positive, and its incidence accounts for 38%-13.5%。Although the incidence of AFP-positive gastric cancer is extremely low, it has unique clinical and pathological characteristics, including liver metastasis, lymph node metastasis, high malignancy, more aggressiveness, and poor prognosis. AFP-positive gastric cancers have different AFP titers. Hiroshi et al. suggested that a high level of AFP cancer is the result of the differentiation of cancer cells into hepatocyte structures, and hepatoid adenocarcinoma of the stomach. Gastric cancer cells that produce low levels of AFP may produce AFP just like the intestinal mucosa in embryonic form, which is more common in intestinal gastric cancer.
4. Viral hepatitis:
Regeneration of hepatocytes after massive destruction of liver cells will result in an increase in alpha-fetoprotein. In general, mild aminotransferase abnormalities do not cause elevated AFP. However, if ALT exceeds 400 IU mL, AFP is more likely to be elevated.
5. Cirrhosis of the liver
Cirrhosis may also be associated with elevated alpha-fetoprotein, but levels are often < 300 g L.
6. Congenital bile duct occlusion, malformed fetuses and other alpha-fetoprotein can be elevated, but the amplitude of the increase is relatively small, and the duration is relatively short.
7. Germ cell tumors (endoderm cancer, teratoma, ** cancer, ovarian cancer): about 50% of patients with germ cell tumors are positive for alpha-fetoprotein (AFP);
How to deal with elevated alpha-fetoprotein?
Short-term (within 3 months).
1. If alpha-fetoprotein is 10 g L, 30 g L, check the liver B ultrasound and liver function, and dynamically recheck the alpha-fetoprotein (once for 2 weeks) until it returns to normal.
2. If alpha-fetoprotein 30 g L, 50 g L, and the liver is checked to enhance CT or MRI, liver function, abnormal prothrombin (PIVKA; DCP), serum alpha-fetoprotein heteroplasm (AFP L3), and dynamic re-examination of AFP (once for 2 weeks) until normal.
3. If alpha-fetoprotein 50 g L, 400 g L, at the same time, the liver is checked to enhance CT or MRI, liver function, abnormal prothrombin (PIVKA; DCP), serum alpha-fetoprotein heteroplasm (AFP L3), and dynamic re-examination of AFP (1 week) until it returns to normal.
If ALT is normal and there is no abnormality in liver CT or MRI, further systemic physical examination is recommended, and the main examination items are: gastrointestinal endoscopy, whole abdomen + chest CT, **color ultrasound (male).
4. If alpha-fetoprotein is 400 g L, the whole abdomen is checked to enhance CT, liver function, abnormal prothrombin (PIVKA; DCP), serum alpha-fetoprotein heteroplasm (AFP L3).
If the ALT is normal and the contrast-enhanced CT is not abnormal, further systemic physical examination is recommended, and the main examination items are: gastrointestinal endoscopy, chest CT, **color ultrasound (male).
Long-term (2 years).
If there is no abnormality in the physical examination and there is no special treatment, dynamic re-examination of alpha-fetoprotein is recommended.
What other relevant tumor markers are there?
Abnormal prothrombin (PIVKA; DCP), plasma cell-free microRNA (miRNA), and serum alpha-fetoprotein heteroplasm (AFP L3) can also be used as markers for early diagnosis of HCC, especially in serum AFP-negative populations.
If you are a high-risk group of liver cancer and the economic conditions are acceptable, you can choose multiple choices for each re-examination and cross-validate. However, if the risk is low, alpha-fetoprotein can be repeated alone.