Poster Session 2: BPH and Prostate Biopsy| Volume 8, ISSUE 8, P578-579, September 2009

N32 Determination of free/total prostate specific antigen ratio in different age categories for diagnosis of prostate carcinoma

      Introduction and Objectives

      The aim of this study was to determine cutoff levels of free/total PSA (f/t PSA) ratios in different age groups for diagnosis of Prostate Carcinoma, focusing on the avoidance of unnecessary prostate biopsies.

      Material and Methods

      A total of 4955 men (a mean age of 63.3±11.3) without a history of prostate surgery and disease ere enrolled into the study. Serum tPSA, fPSA and f/t PSA ratios were determined for the study population and for different age categories. All males who had suspicious digital rectal examination and tPSA >4 ng/mL underwent transrectal ultrasonography-guided prostate biopsy. Receiver operating characteristic (ROC) curves for each group were generated by plotting the sensitivity vs. 1 − specificity for the f/t PSA ratio. The sensitivity and specificity were obtained using different f/t PSA ratio cutoffs for different age groups.


      Prostate cancer was detected in 109 patients (2.2%). There were 657 patients with a PSA level of 4–10 ng/ml. According to sensitivity and specificity f/t% PSA cutoff points were 13%, 18%, 14% and 13% in 50–59, 60–69, >70 and all ages categories in patients with initial PSA level of 4–10 ng/ml.


      The current study showed that the use of f/t PSA ratio in patients with PSA levels of 4–10 ng/mL should enhance the specificity of PSA screening and decrease the number of unnecessary biopsies. f/t PSA levels may show dissimilarities according to age, so further studies are warranted to identify this relationship.