Alpha Fetoprotein (AFP)

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Alpha Fetoprotein (AFP) is a protein that is normally produced by the liver and yolk sac of an embryo or fetus. Alpha-fetoprotein may also be produced in the adult, but only at very low levels. Alpha-fetoprotein is a glycoprotein and belongs to a group of embryonic proteins called albumins. It is the most abundant protein produced by the fetal liver (accounts for about 80% of all the proteins in the fetus). Although AFP is found throughout the body, it is only normally present in blood after birth.There are two different forms of AFP: free and bound. Bound AFP is attached to a carrier molecule called beta-globulin or albumin, while free AFP floats freely in the blood serum. The protein's level in fetal serum increases with gestational age. Because AFP is present in only small amounts in an adult, elevated levels of this protein in an adult indicate the presence of a cancer in one or more organs. One of the most common cancers that may produce this substance is a primary hepatocellular carcinoma or malignant liver tumor. Elevated levels of AFP in an adult may also indicate testicular cancer or germ cell tumors, such as choriocarcinoma, embryonal carcinoma and yolk sac tumor. The presence of elevated levels of AFP in an adult may also indicate the presence of a lung, ovarian or pancreatic cancer. Other cancers that may cause elevated levels of AFP in adults include stomach and breast cancer.

A health care professional may order an alpha-fetoprotein test for a patient in order to screen for the presence of cancer or liver disease. Although the test may be less accurate in an adult, it can still provide doctors with valuable information. AFP is also used to monitor newborns who are at risk for certain defects or conditions, such as neural tube defects and Down syndrome. A high level of alpha-fetoprotein in a fetus can indicate that there may be abnormalities present.

In conclusion, alpha-fetoprotein is a protein that is normally produced by the liver and yolk sac of an embryo or fetus. High levels of this protein in an adult may indicate the presence of cancer in one or more organs, including liver, lung, ovarian or pancreatic cancer. It can also be used to monitor newborns who are at risk for certain conditions. While we offer AFP tests, it is important to understand the broader implications of blood testing in our article on "Understanding blood tests".

Alpha-fetoprotein is an important biomarker that can be used to screen for and monitor a variety of cancers, including liver cancer, lung cancer, ovarian cancer, breast cancer, and others. It can also be used to track the progression of disease in adults or newborns who are at risk for certain conditions. While the test is not as accurate in adults, it still provides valuable information that can help healthcare professionals diagnose and treat cancer effectively. Whether measuring AFP levels to screen for cancer or monitor disease progression, it is an important tool that can help healthcare providers better care for their patients.