AFP
Meaning of AFP: AFP is the abbreviation for alpha-fetoprotein, a substance produced by a fetus and used as both a prenatal screening marker and a tumor marker.
Definition of AFP
AFP stands for alpha-fetoprotein, a protein normally produced by a developing fetus, mainly by the fetal liver and yolk sac. Outside of pregnancy, AFP is normally present only in very low or undetectable amounts in the blood.
AFP measurement is used during pregnancy as one component of prenatal screening, since abnormal levels can be associated with certain conditions affecting fetal development. In adults who are not pregnant, an elevated AFP level can point toward primary liver cancer or a germ cell tumor arising in the testicle or ovary.
Because pregnancy itself raises AFP substantially, this marker is interpreted very differently depending on whether the person being tested is pregnant, and an elevated level in either setting is generally followed by additional testing or imaging to clarify its cause.
Also known as
Used in a sentence
AFP was measured along with imaging in the workup of a testicular mass.
Good to know
AFP levels are expected to be elevated during pregnancy, so an abnormal result outside of that context is interpreted very differently than the same elevated level found in a pregnant person.