Evaluation of an EIA method for measuring serum levels of the estrogen metabolite 2-hydroxyestrone in adults.
Two-hydroxyestrone (2OHE-1) and 16alpha-hydroxyestrone (16OHE-1) are two estrogen metabolites that may play important roles in the development or promotion of breast cancer. Our study assessed the reliability of a newly developed kit procedure for measuring 2OHE-1. Although under certain conditions the assay would not distinguish 2OHE-1 from estriol, or possibly 2-methoxyestrone, steroids such as 17beta-estradiol, estrone and 16OHE-1 should not interfere with the test. Our study evaluated the precision of this enzyme immunoassay (EIA) kit for measuring 2OHE-1 levels in serum obtained from healthy men and women. As a result of several replicate analyses of specimens obtained from 18 men and 20 women, we found that the within-run coefficients of variation (CVs) were approximately 20% and the among run CVs, 30%. Because the SD for the procedure is high, the limit of detection (LOD) was also high (130 ng/l). Nonetheless the assay could distinguish between 2OHE-1 levels in men (128 ng/l) and women (332 ng/l) because we performed a large number of analyses on each specimen. Improving the reproducibility of the assay would reduce the: 1. LOD; number of replicates needed to obtain reliable estimates of 2-OHE-1 levels; amount of time, effort, and cost for each analysis; and greatly improve the reliability of the method. Because the within-run variability is relatively smaller than the total variability (among run + within run), use of the assay for determining differences among groups could be justified only when measurements were made in a single run.
Spierto
F W
FW
Division of Laboratory Sciences, National Center for Environmental Health Centers for Disease Control and Prevention, Atlanta, GA 30333, USA. fws1@cdc.gov
Gardner
F
F
Smith
S J
SJ
D000328:Adult; D002393:Estrogens, Catechol / Q000378:metabolism*; D005260:Female; D006801:Humans; D006894:Hydroxyestrones / Q000097:blood*; D007124:Immunoenzyme Techniques / Q000379:methods*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012680:Sensitivity and Specificity
D002393:Estrogens, Catechol; D006894:Hydroxyestrones; C024980:2-hydroxyestrone