Use of Prostate-Specific Antigen (PSA) Isoforms for the Detection of Prostate Cancer in Men with a PSA Level of 2–10 ng/ml: Systematic Review and Meta-Analysis

Abstract Objective: Measurement of serum prostate-specific antigen (PSA) for the detection of prostate cancer has poor specificity in men with PSA levels between 2 and 10ng/ml. It has been suggested that measurement of the ratio of free to total PSA (f/tPSA) or complexed PSA (cPSA) might offer an improvement. We performed a systematic review and meta-analysis to evaluate the diagnostic performance of these tests among men with PSA levels between 2 and 10ng/ml. Methods: Data on sensitivity and specificity were extracted from 66 eligible studies. Likelihood ratios and summary receiver operating characteristic curves were estimated and possible sources of heterogeneity between studies examined. Results: Use of the f/tPSA or the cPSA test improved diagnostic performance among men with a total PSA (tPSA) of 2–4 or 4–10ng/ml compared to tPSA alone. The diagnostic performance of the f/tPSA test was significantly higher in the tPSA range of 4–10ng/ml compared to a tPSA range of 2–4ng/ml ( p Conclusions: The use of the f/tPSA or cPSA test among men with PSA levels between 2 and 10ng/ml can reduce the number of unnecessary biopsies whilst maintaining a high cancer detection rate.