Abstract
Background
Tumor markers are used for diagnosing cancers and monitoring responses to cancer therapy. In this study, we evaluated the performance of Lumipulse G1200 (Fujirebio, Japan), a fully automated serum analyzer, for immunoassays of tumor markers.
Methods
We determined the precision and linearity of assays performed using Lumipulse G1200 and the correlation between the results of this and other analyzers used for tumor markers according to the guidelines of the Clinical and Laboratory Standards Institute (CLSI). We used 9 tumor markers, namely, carcinoembryonic antigen, α-fetoprotein, cancer antigen 125, cancer antigen 15-3 (CA 15-3), cancer antigen 19-9, prostate specific antigen, protein induced by vitamin K absence or antagonist-II, and pepsinogens I and II. Further, we validated reference intervals using 20 serum samples of healthy individuals.
Results
Lumipulse G1200 yielded acceptable precision with total CV≤5% and within-run CV≤3% for all markers. Total CV for all markers was 2.4-3.7%, with the exception of CA 15-3 and pepsinogens I and II (CV, 4.0-5.0%). Linearity was observed for all markers over the entire analytical range. Results of Lumipulse G1200 were in good agreement with those of currently used analyzers with correlation coefficients>0.975 for all markers, except pepsinogen I (0.9569). The reference intervals provided by the manufacturer met the criteria mentioned in the CLSI guideline.
Figures and Tables
Table 1
*Within-subject biological variation and desirable analytical precision criteria are referred from Rico et al. [8] and the biological variation database specification in Westgard's web site (http://www.westgard.com/biodatabase1.htm) [11].
Abbreviations: CVw, within-subject biologic variation; AFP, α-fetoprotein; CEA, carcinoembryonic antigen; CA 15-3, cancer antigen 15-3; CA 19-9, cancer antigen 19-9; CA 125, cancer antigen 125; PSA, prostate specific antigen; PIVKA-II, protein induced by vitamin K absence or antagonist-II; NA, not applicable.
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