title: Free prostate-specific antigen provides more precise data on benign prostate volume than total prostate-specific antigen in korean population.
abstract: OBJECTIVE
  To investigate the efficacy of total prostate-specific antigen (tPSA) and free prostate-specific antigen (fPSA) for the estimation of prostate volume (PV) in pathologically-proven benign prostatic hyperplasia (BPH) patients.
  
  
  METHODS
  From January 2010 to March 2013, 165 Korean men with a PSA less than 10 ng/mL who were diagnosed without prostate cancer by prostate biopsy were enrolled. Patients were classified into three age groups: ≤60, 61-70, and >70 years old. The results were organized to estimate and compare the ability of serum tPSA and fPSA to assess the PV.
  
  
  RESULTS
  Enrolled patients had a median age of 63.5 years (44 to 80), a median tPSA of 5.72 ng/mL, a median fPSA of 0.98 ng/mL and a median PV of 53.68 mL, respectively. Among the associations between tPSA, fPSA, age, and PV, the highest correlation was verified between fPSA and PV (r=0.377, P<0.0001); the correlation coefficient between tPSA and PV was much lower (r=0.262, P<0.001). All stratified age cohorts showed the same findings. The ROC curves (for PV greater than 30, 40, and 50 mL) showed that fPSA (area under the curve [AUC]=0.781, 0.718, and 0.700) outperformed tPSA (AUC=0.657, 0.583, and 0.67) in its ability to predict clinically significant PV enlargement.
  
  
  CONCLUSIONS
  Both tPSA and fPSA significantly correlated with PV in Korean men, while the correlation efficiency between fPSA and PV was more powerful. fPSA may be a useful tool in making therapeutic decisions and follow-up management in BPH patients.
authors.affiliation: Department of Urology, Korea University Ansan Hospital, Korea University College of Medicine, Ansan, Korea.
authors.forename: Hoon
authors.initials: H
authors.lastname: Choi
authors.forename: Jae Young
authors.initials: JY
authors.lastname: Park
authors.forename: Ji Sung
authors.initials: JS
authors.lastname: Shim
authors.forename: Jae Heon
authors.initials: JH
authors.lastname: Kim
authors.forename: Jae Hyun
authors.initials: JH
authors.lastname: Bae
keywords: Organ volume; Prostate-specific antigen; Prostatic hyperplasia