Comparison of whole plasma and perchloric acid-extracted plasma assays for carcinoembryonic antigen.
A direct, paired, comparison was made of two plasma radioimmunoassays for carcinoembryonic antigen (CEA), between a perchloric acid-extracted, ammonium sulphate precipitation method; and a whole-plasma, double-antibody method. For both assays the same preparations of standard CEA, 125I-labelled CEA, and anti-CEA serum were used. Plasma samples were taken from young healthy subjects (24), cancer-free hospital inpatients (44) and cancer-proven untreated patients (94). Within-batch and between-batch variation were both greater for the extracted-plasma method. Cancer discriminatory ability was assessed by probabilistic means. With cancer-free inpatients as the reference group, no difference between the assay methods was revealed. With young healthy subjects as the reference group the whole-plasma assay was superior.
D000328:Adult; D000368:Aged; D002272:Carcinoembryonic Antigen / Q000032:analysis*; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000276:immunology; D010472:Perchlorates; D010949:Plasma / Q000032:analysis; D011863:Radioimmunoassay / Q000379:methods
D002272:Carcinoembryonic Antigen; D010472:Perchlorates