CEA-S — A More Specific CEA?

IN the current issue of the Journal, Edgington et al. report an assay for an isomeric species of carcinoembryonic antigen (CEA-S), a glycoprotein similar to carcinoembryonic antigen (CEA) isolated from colonic cancer that appears to be at least as sensitive as CEA in the detection of digestive tract cancer (80 per cent positivity) and colonic cancer (86 per cent) while yielding fewer elevated (or "positive") CEA-S values with other cancers (primarily breast and lung) and with non-neoplastic diseases of the digestive tract. Many investigators have been searching for such a tumor marker for use as a potential screening test . . .