Performance Evaluation of the Total ProstateSpecific Antigen (PSA), Free PSA, and [–2]proPSA Assay for Calculation of the Prostate Health Index Using the UniCel DxI 800 Analyzer (original) (raw)

2019, Journal of Laboratory Medicine and Quality Assurance

Background: Prostate-specific antigen (PSA) is widely used as a tumor marker of prostate cancer, but it is not specific for cancer. Numerous efforts have been made to find another tumor marker that can replace PSA. Recently, the Prostate Health Index (PHI) has been introduced, which shows higher diagnostic performance for prostate cancer than PSA. In this study, we evaluated the performance of the UniCel DxI 800 (Beckman Coulter, USA) for quantitative measurement of total PSA (tPSA), free PSA (fPSA), and [-2]proPSA used for calculating the PHI. Methods: The precision, linearity, and limit of detection of the three items, as well as the correlation between the UniCel DxI 800 (Beckman, USA) and a comparable instrument in the Asan Medical Center, the Alinity i (Abbott, USA), were evaluated in accordance with the Clinical Laboratory Standards Institute guidelines. Results: The total coefficient of variation for the three items was less than 5%. Linearity was observed for each manufacturer-claimed analytical measurement range, with R 2 =0.99. The claimed limit of blank and limit of detection were verified. The results of the UniCel DxI 800 showed good correlation with those of the Alinity i (tPSA, r=0.995; fPSA, r=0.994). Conclusions: The UniCel DxI 800 showed good analytical performance. Therefore, it will be useful to use the UniCel DxI 800 in the clinical laboratory to measure the diagnostic markers of prostate cancer.