[Comparison and analysis of two methods for serum free prostate-specific antigen (PSA) detection].

Objective: To analyze the clinical performance of free prostate-specific antigen (fPSA) detection by ECLIA method, and evaluate whether ECLIA is suitable for clinical use.
Methods: 341 samples were collected and tested prostate-specific antibodies with CMIA and ECLIA methods. These samples contain: 97 samples with abnormal high PSA value tested by CMIA method, and 244 normal PSA samples. Use CMIA as the reference method, and detect fPSA, tPSA levels, and the ratio of fPSA/tPSA. Analyze the testing results with statistical methods.
Results: Compared with CMIA, correlation coefficent of ECLIA fPSA detection is 0.99; correlation coefficent of f/tPSA ratio detection is 0.96; the sensitivity, specificity of ECLIA f/tPSA ratio detection are 85.71%, 92.6% respectively, the agreement rate with ECLIA is 87.4%. No cross reaction with bilirubin, lipohemia, hemolysis, RF, CEA, AFP, CA125, CA153, CA199 were found in the tests.
Conclusion: The ECLIA method for free prostate-specific antigen detection showed good clinical performance; and is suitable for clinical use.