[Immunochemiluminometric assay (Automated Chemiluminescence System ACS: 180) for CEA].
We examined Automated Chemiluminescence System ACS: 180 for CEA assay, especially about confidence of the functional sensitivity. Serum CEA levels of normal subjects and patients were measured not only with ACS: 180 but also with immunoradiometric assay (CEA kit [Daiichi] II). Using ACS: 180 assay for CEA, intra-assay coefficients of variation (C.V.s) were 4.06% at 1.97 ng/ml, 1.62% at 17.3 ng/ml, and 2.28% at 81.3 ng/ml. Interassay C.V.s were 4.02% at 1.99 ng/ml, 1.21% at 16.5 ng/ml, and 3.44% at 79.4 ng/ml. The detection limit (functional sensitivity) of ACS: 180 assay for CEA was 0.4 ng/ml by the precision profile. The coefficient of correlation of 164 sera, which CEA values were among 0.4-100 ng/ml (working range of ACS: 180), between with ACS: 180 and with CEA kit [Daiichi] II was R = 0.942, y = 1.07 x +0.09 (p < 0.05). Seven (13.2%) normal subjects (n = 53) and 45 (34.1%) patients with malignant diseases (n = 132) had higher serum CEA levels than the cut off value (2.5 ng/ml). The sera of 82 malignant patients who had both pre- and post-operation sample were determined. Sixty-five patients of them were decrease after operation. These results of ACS: 180 resembled to that of CEA kit [Daiichi] II. We conclude that ACS: 180 for CEA assay was precise enough to measure below the cut off value, and had good performance of its speed (short incubation) and convenience.
Department of Radiology, Yamagata University School of Medicine.
Y
Y
Manaka
M
M
Watanabe
T
T
Akutsu
A
A
Komatani
K
K
Yamaguchi
D002272:Carcinoembryonic Antigen / Q000032:analysis*; D006801:Humans; D007118:Immunoassay; D015592:Immunoradiometric Assay; D008163:Luminescent Measurements; D011237:Predictive Value of Tests; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity
D002272:Carcinoembryonic Antigen; D011933:Reagent Kits, Diagnostic