|
|
||||||||
Articles |
Divisions of
1
Endocrinology and
2
Informatics, National Institute for Biological Standards and Control, Blanche Lane, South Mimms, Potters Bar, Herts EN6 3QG, United Kingdom.
3
Department of Urology, Stanford University School of
Medicine, Stanford, CA 94305-5118.
a Author for correspondence. Fax 44-01707-646730; e-mail brafferty{at}nibsc.ac.uk
Background: Prostate-specific antigen (PSA) measurements in serum by immunoassay are widely used in the screening, diagnosis, and monitoring of patients with prostate cancer although the lack of common reference reagents has led in the past to wide differences in estimates. We report here the results of a WHO international collaborative study in which two preparations of PSA representative of the main immunoreactive components in serum, free PSA and PSA 90:10, and a preparation of recombinant DNA-derived PSA were assessed as potential standards for the calibration of diagnostic immunoassays for PSA.
Methods: Coded vials of the candidate materials and serum preparations containing PSA in the clinically important range were provided to the 10 laboratories in the study, and participants were asked to perform PSA assays currently in use in their laboratories. Data from 89 immunoassays by 26 different method-laboratory combinations were contributed to the study and analyzed centrally at the National Institute for Biological Standards and Control.
Results: Potency estimates of the preparations relative to the in-house calibrators were in good agreement with the target value of 1 µg of total PSA/vial, the preparation of free PSA giving 1.10 µg/vial (95% confidence interval, 0.991.21 µg/vial) and PSA 90:10, 1.11 µg/vial (95% confidence interval, 1.041.18 µg/vial). No immunoreactivity was detected in ampoules containing the recombinant material. Use of a common standard of PSA 90:10 significantly reduced the between-laboratory geometric coefficients of variation for serum samples included in the study and gave a much narrower range of potency estimates.
Conclusions: The preparation of free PSA was established by WHO as the First International Standard for PSA (free) with an assigned content of 1 µg of total PSA per vial. In addition, the preparation of bound PSA was established as the First International Standard for PSA (90:10) with an assigned content of 1 µg of total PSA per vial.
The following articles in journals at HighWire Press have cited this article:
![]() |
T. Fortin, A. Salvador, J. P. Charrier, C. Lenz, X. Lacoux, A. Morla, G. Choquet-Kastylevsky, and J. Lemoine Clinical Quantitation of Prostate-specific Antigen Biomarker in the Low Nanogram/Milliliter Range by Conventional Bore Liquid Chromatography-Tandem Mass Spectrometry (Multiple Reaction Monitoring) Coupling and Correlation with ELISA Tests Mol. Cell. Proteomics, May 1, 2009; 8(5): 1006 - 1015. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. M. Sturgeon, M. J. Duffy, U.-H. Stenman, H. Lilja, N. Brunner, D. W. Chan, R. Babaian, R. C. Bast Jr., B. Dowell, F. J. Esteva, et al. National Academy of Clinical Biochemistry Laboratory Medicine Practice Guidelines for Use of Tumor Markers in Testicular, Prostate, Colorectal, Breast, and Ovarian Cancers Clin. Chem., December 1, 2008; 54(12): e11 - e79. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. H. Jansen, M. Roobol, C. H. Bangma, and R. H. N. van Schaik Clinical Impact of New Prostate-Specific Antigen WHO Standardization on Biopsy Rates and Cancer Detection Clin. Chem., December 1, 2008; 54(12): 1999 - 2006. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. M. Sturgeon, B. R. Hoffman, D. W. Chan, S.-L. Ch'ng, E. Hammond, D. F. Hayes, L. A. Liotta, E. F. Petricoin, M. Schmitt, O. J. Semmes, et al. National Academy of Clinical Biochemistry Laboratory Medicine Practice Guidelines for Use of Tumor Markers in Clinical Practice: Quality Requirements Clin. Chem., August 1, 2008; 54(8): e1 - e10. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Lilja, D. Ulmert, T. Bjork, C. Becker, A. M. Serio, J.-A. Nilsson, P.-A. Abrahamsson, A. J. Vickers, and G. Berglund Long-Term Prediction of Prostate Cancer Up to 25 Years Before Diagnosis of Prostate Cancer Using Prostate Kallikreins Measured at Age 44 to 50 Years J. Clin. Oncol., February 1, 2007; 25(4): 431 - 436. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. A.R. Kort, F. Martens, H. Vanpoucke, H. L. van Duijnhoven, and M. A. Blankenstein Comparison of 6 Automated Assays for Total and Free Prostate-Specific Antigen with Special Reference to Their Reactivity toward the WHO 96/670 Reference Preparation Clin. Chem., August 1, 2006; 52(8): 1568 - 1574. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Stephan, M. Klaas, C. Muller, D. Schnorr, S. A. Loening, and K. Jung Interchangeability of Measurements of Total and Free Prostate-Specific Antigen in Serum with 5 Frequently Used Assay Combinations: An Update Clin. Chem., January 1, 2006; 52(1): 59 - 64. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Haese, V. Vaisanen, J. A. Finlay, K. Pettersson, H. G. Rittenhouse, A. W. Partin, D. J. Bruzek, L. J. Sokoll, H. Lilja, and D. W. Chan Standardization of Two Immunoassays for Human Glandular Kallikrein 2 Clin. Chem., April 1, 2003; 49(4): 601 - 610. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. G. Blijenberg, M. F. Wildhagen, C. H. Bangma, J. A. Finlay, V. Vaisanen, and F. H. Schroder Comparison of Two Assays for Human Kallikrein 2 Clin. Chem., February 1, 2003; 49(2): 243 - 247. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Semjonow, F. Oberpenning, C. Weining, M. Schon, B. Brandt, G. De Angelis, A. Heinecke, M. Hamm, P. Stieber, L. Hertle, et al. Do Modifications of Nonequimolar Assays for Total Prostate-specific Antigen Improve Detection of Prostate Cancer? Clin. Chem., August 1, 2001; 47(8): 1472 - 1475. [Full Text] [PDF] |
||||
![]() |
R. M. Kisabeth Laboratory Adaptations--Changing Expectations Clin. Chem., August 1, 2001; 47(8): 1509 - 1515. [Full Text] [PDF] |
||||
![]() |
U.-H. Stenman Immunoassay Standardization: Is It Possible, Who Is Responsible, Who Is Capable? Clin. Chem., May 1, 2001; 47(5): 815 - 820. [Full Text] [PDF] |
||||
![]() |
D. W. Chan and L. J. Sokoll WHO First International Standards for Prostate-specific Antigen: The Beginning of the End for Assay Discrepancies? Clin. Chem., September 1, 2000; 46(9): 1291 - 1292. [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |