Background :
Cancer of the prostate is the most common malignancy in old males. Prostate-specific antigen(PSA) has demonstrated excellent clinical utility in evaluating patients with prostate cancer.
Methods:
I evaluated the analytical performance of the microparticle enzyme immunoassay (MEIA) for measurement of serum prostate-specific antigen(Imx-PSA, Abbott, USA).
Results:
Imx-PSA showed good precision (1.8%-2.5% within-run CV, 2.7-6.0% between-run CV) and good recovery rate (97.3%). Linearity was well maintatined in the range of 0-100ng/ml. The low detection limit was 0.134 ng/ml. Correlation of Imx-PSA(MEIA)
with
immunoradiometric assay(IRMA) (PSA MAIA Clone; Serono diagnostics, Italy) were Y(MEIA)=0.4353X(IRMA)+2.40,(n=67, r=0.93, P>0.05) and Imx-PSA with chemiluminometric assay(CIA)(CIBA Corning ACS-PSA, Ciba corning diagnostics, USA) were
Y(MEIA)=0.518X(CIA)-0.0537, (n=67, r=0.99, P<0.05) and the PSA by ACS-PSA was 1.8 times higher value than Imx-PSA. The normal reference interval for Imx-PSA in healthy men was 0-1.93ng/ml. At a cut-off value of 4.0ng/ml, the sensitivity and
specificity
of the test were 92.9 and 71.7%, respectively.
Conclusions:
The Imx-PSA immunoassay, with the convenience of automation, nonisotopic handling, which is useful for earlier detection of prostate carcinoma and residual or recurrent disease after prostatectomy.
|