Relation of free PSA/total PSA in serum for differentiating between patients with prostatic cancer and benign hyperplasia of the prostate: which cutoff should be used?

A review on literature data is given concerning free prostate-specific antigen (f-PSA) and the corresponding cutoffs of f-PSA/t-PSA for differentiating patients with cancer of the prostate from those with benign prostatic hyperplasia. The special importance of the diagnostic criterion (sensitivity, specificity, efficiency) for establishing the cutoff is demonstrated. On the basis of our own data, the application of the f-PSA% is recommended as an additional decision criterion for biopsy.