Indications:
The alpha-fetoprotein assay is useful for detecting and monitoring especially the therapeutic development of primary liver cancer (carcinoma hépathocellulaires).
Principre:
This glycoprotein produced by the liver is the main protein of fetal serum; it happens physiologically in maternal blood;it is normally absent in adults.
Technique:
Sampling 5 mL of blood in a dry tube.
The assay can also be performed from the puncture of ascites fluid.
The assay methods are used radioimmunoassay or enzyme immunoassay techniques.
Results:
Normal values:
– Adult: <20 ng / mL;
– Child from 10 000 to 100 000 ng / mL at birth, with a rapid decrease to the point that the adult rate is reached at the end of the first year;
– Pregnancy: <300 ng / mL at 32 weeks.
– Levels above 400 ng / mL were observed in 70% of liver carcinoma-type tumors, but such rates can be found in hepatitis or cirrhosis, and therefore can not be a reliable marker cancer; he must then confront biology and clinic for diagnosis (liver ultrasound).
– However, after removal of the tumor, AFP is a good way of monitoring a rate hike then being a sign of tumor recurrent disease;
– There is the same phenomenon in tumors non-seminoma testicular, where the elevation of AFP accompanies that of β-hCG;
– AFP is also increased in ovarian cancers, pancreas, stomach or bronchi;
– In case of fetal malformation, AFP is increased in amniotic fluid between the 14th and 16th week, especially for neural tube defects (spina bifida, anencephaly).
Cost:
B70.
Practical advice:
Pregnancy modifies the AFP rate results.
