The emerging role of carcinodevelopmental antigens in the clinical laboratory.

Patterns of carcinoembryonic antigens (CEA) in fetal gut, seminal plasma, and amniotic fluids were investigated. In fetal gut the broadest range of CEA-expression occurred during the period of maximal mucosal differentiation. While normal adult colon or other fetal stages expressed lower quantitative and qualitative amounts of CEA, maximal CEA expression could be found in a pool of 20 primary adenocarcinomas of the colon. Low levels of CEA in seminal plasma were associated with subfertile, poorly differentiated sperm as opposed to CEA levels found in either normal ejaculates or those obtained from vasectomized, previously fertile males. In amniotic fluid CEA remained at a constant level between the 16th and 22nd week in utero as did fructose and urea levels. Glucose and histaminase levels showed great variance. The relationship of these latter findings to genetic defects is currently being investigated. These data suggest that an ever increasing number of biologic samples will be tested in the clinical laboratories for carcinodevelopmental antigen levels. These will be used for the prognosis and/or diagnosis of abnormal differentiation patterns in patients with cancer or in the developing fetus.