fetoprotein /-prō″tēn/ [L, fetus + Gk, proteios, first rank] , an antigen that occurs naturally in fetuses and occasionally in adults as the result of certain diseases. An increased amount of alpha-fetoprotein in the fetus is diagnostic for neural tube defects. The presence of beta-fetoprotein in the blood of adults is associated with leukemia, hepatoma, sarcoma, and other neoplasms. See also alpha-fetoprotein, beta-fetoprotein.
