Lab Med Online.  2012 Jul;2(3):131-138.

Evaluation of the Performance of Lumipulse G1200 for Tumor Marker Assays

• Cho JH
• Lee CM
• Park CM
• Moon HW
• Hur M
• Yun YM
• Lee W
• Chun S
• Min WK

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, alpha-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< or =5% and within-run CV< or =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.
CONCLUSIONS
Assays using Lumipulse G1200 had high precision, clinically acceptable linearity, and good correlation with the established assays. This indicates that Lumipulse G1200 can be potentially used in routine laboratories.

Keyword

Tumor maker; Lumipulse G1200; Precision; Linearity; Method comparison

MeSH Terms

alpha-Fetoproteins
Carcinoembryonic Antigen
Immunoassay
Pepsinogen A
Pepsinogens
Prostate-Specific Antigen
Biomarkers, Tumor
Vitamin K
Carcinoembryonic Antigen
Pepsinogen A
Pepsinogens
Prostate-Specific Antigen
Vitamin K
alpha-Fetoproteins

Figure

• 

  Fig. 1 Linearity of concentrations estimated by the Lumipulse G1200 assay for 9 tumor markers. Concentration of each tumor marker is shown on a separate graph (A-I). Abbreviations: AFP, α-fetoprotein; CEA, carcinoembryonic antigen; CA 125, cancer antigen 125; CA 15-3, cancer antigen 15-3; CA 19-9, cancer antigen 19-9; PSA, prostate specific antigen; PIVKA-II, protein induced by vitamin K absence or antagonist-II.

• 

  Fig. 2 Regression plots of concentrations of 9 tumor markers measured using Lumipulse G1200 and other analyzers. (A) AFP: Modular analytics E170 vs. Lumipulse G1200, (B) AFP: Architect i2000 vs. Lumipulse G1200, (C) CEA: Modular analytics E170 vs. Lumipulse G1200, (D) CEA: Architect i2000 vs. Lumipulse G1200, (E) CA 125: Modular analytics E170 vs. Lumipulse G1200, (F) CA 125: Architect i2000 vs. Lumipulse G1200, (G) CA 19-9: Modular analytics E170 vs. Lumipulse G1200, (H) CA 19-9: Cobas 6000 vs. Lumipulse G1200, (I) CA 15-3: Modular analytics E170 vs. Lumipulse G1200, (J) PSA: Modular analytics E170 vs. Lumipulse G1200, (K) PIVKA-II: EP-one vs. Lumipulse G1200, (L) Pepsinogen I: TBA-200 FR Neo vs. Lumipulse G1200, (M) Pepsinogen II: TBA-200 FR Neo vs. Lumipulse G1200. The blue line represents the linear regression, and the gray line is a theoretical line with a slope of 1.0 and a Y intercept of 0. Abbreviations: AFP, α-fetoprotein; CEA, carcinoembryonic antigen; CA 125, cancer antigen 125; CA 15-3, cancer antigen 15-3; CA 19-9, cancer antigen 19-9; PSA, prostate specific antigen; PIVKA-II, protein induced by vitamin K absence or antagonist-II.

• 

  Fig. 3 Bland-Altman plots showing the means of the paired difference in the concentrations of tumor markers measured using Lumipulse G1200 and different analyzers. (A) AFP: Modular analytics E170 vs. Lumipulse G1200, (B) AFP: Architect i2000 vs. Lumipulse G1200, (C) CEA: Modular analytics E170 vs. Lumipulse G1200, (D) CEA: Architect i2000 vs. Lumipulse G1200, (E) CA 125: Modular analytics E170 vs. Lumipulse G1200, (F) CA 125, Architect i2000 vs. Lumipulse G1200, (G) CA 19-9: Modular analytics E170 vs. Lumipulse G1200, (H) CA 19-9: Cobas 6000 vs. Lumipulse G1200, (I) CA 15-3: Modular analytics E170 vs. Lumipulse G1200, (J) PSA: Modular analytics E170 vs. Lumipulse G1200, (K) PIVKA-II: EP-one vs. Lumipulse G1200, (L) Pepsinogen I: TBA-200 FR Neo vs. Lumipulse G1200, (M) Pepsinogen II: TBA-200 FR Neo vs. Lumipulse G1200. Thick solid lines show the means of the paired differences, and thin solid lines represent lines of identity. Dashed lines show 95% limits of agreement (means of paired differences±1.96 SD). Abbreviations: AFP, α-fetoprotein; CEA, carcinoembryonic antigen; CA 125, cancer antigen 125; CA 15-3, cancer antigen 15-3; CA 19-9, cancer antigen 19-9; PSA, prostate specific antigen; PIVKA-II, protein induced by vitamin K absence or antagonist-II.

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