Bayer Immuno 1 PSA Assay: an automated, ultrasensitive method to quantitate total PSA in serum.

The Bayer Immuno 1 PSA Assay measures total PSA in human serum and demonstrates excellent performance with an interassay CV < or = 3.4% and a biological detection limit of 0.03 microgram/L. No significant interference from common hormonal and chemotherapeutic drugs, kallikrein, prostatic acid phosphatase, and trypsin, or elevated levels of total bilirubin, hemoglobin, triglycerides, and IgG was observed. The 95th percentile values for healthy individuals increased with age from 3.0 micrograms/L for males 50-59 years and 3.3 micrograms/L for males 60-69 years, to 4.6 micrograms/L for males > or = 70 years. Clinical studies with retrospective samples demonstrated correspondence between serial measurements of PSA and clinical outcome for 98% of 159 prostate cancer patients. Clinical sensitivity for patients with clinical evidence of disease, untreated at the time of specimen draw, increased with increasing stage from 77.5-100%. Specificity of 60-70% for BPH and other benign urogenital diseases was consistent with previous findings. Bayer Immuno 1 PSA Assay values for 2131 specimens from healthy subjects and patients with prostate cancer, BPH, and other malignant and nonmalignant diseases correlated well with the Abbott IMx PSA Assay over the range 0.0-6,238 micrograms/L (Y = 1.10 x + 0.02). The Bayer Immuno 1 PSA Assay provides automated ultrasensitive, precise, and equimolar measurement of total PSA in human serum.