Simultaneous determination of plasma and urinary carcinoembryonic antigen levels.
The results of simultaneous plasma and urinary CEA levels in 14 patients are described. The aim was to determine whether urinary CEA derived from plasma or arose independently in the urinary tract. The method of reductio ad absurdum is followed. It is assumed that CEA in the urine is derived from plasma, and CEA clearance values for each patient are calculated. These varied widely from zero to a theoretical infinity. On this basis and from previous experimental evidence, it is concluded that urine is independent of plasma CEA. The finding, however, in some individuals of "anti-CEA"-like factor(s) distorting urinary CEA determination makes for some reservations about the safety of the conclusion. It is, however, certain that with the presently available technology, present urinary and plasma CEA values cannot be correlated.
D002272:Carcinoembryonic Antigen / Q000032:analysis* / Q000652:urine; D003110:Colonic Neoplasms / Q000097:blood / Q000276:immunology* / Q000652:urine; D006801:Humans
D002272:Carcinoembryonic Antigen