title: Prostate specific antigen velocity per prostate volume: a novel tool for prostate biopsy prediction.
abstract: OBJECTIVE
  To investigate whether altered prostate specific antigen (PSA) levels due to individual prostate growth may affect the PSA velocity (PSAV).
  
  
  METHODS
  Between January 2000 and December 2009, a total of 159 men with at least 2 transrectal ultrasonography (TRUS) procedures and concurrent PSA measurements underwent prostate biopsy because of suspicion of prostate cancer. We measured PSAV, prostate volume velocity (PVV), PSA density (PSAD), PSAD velocity (PSADV), and PSAV per initial volume. We then classified the total group into a prostate cancer (PC) group and non-PC group, and compared the 2 groups. We investigated which variables were exact to predict prostate biopsy using univariate and multivariate analyses, and assessed the diagnostic performance using the receiver operating characteristic (ROC) curve.
  
  
  RESULTS
  PVV showed a positive correlation with initial prostate volume in the total and non-PC group; PVV showed a positive correlation with PSAV, and initial prostate volume correlated with PSAV in the non-PC group. The PC group showed smaller prostate volumes, higher PSAD, higher PSADV, higher PSAV per initial volume, and longer follow-up periods. After adjusting for confounding factors, the odds ratios of prostate cancer across the quartile of PSAVD were 1, 1.889, 3.226, and 7.125 (P for trend = .007), and PSAV per initial volume were 1, 2.924, 2.937, and 7.536 (P for trend = .031). On the ROC curve, the areas under the curves (AUC) of PSAV per initial volume were higher than for PSAV and PSADV.
  
  
  CONCLUSIONS
  Altered PSA levels due to individual prostate growth may affect the use of PSAV to predict prostate biopsy outcomes in follow-up.
authors.affiliation: Department of Urology, Chung-Ang University, College of Medicine, Seoul, South Korea.
authors.forename: Se Young
authors.initials: SY
authors.lastname: Choi
authors.forename: In Ho
authors.initials: IH
authors.lastname: Chang
authors.forename: Young Sun
authors.initials: YS
authors.lastname: Kim
authors.forename: Tae-Hyoung
authors.initials: TH
authors.lastname: Kim
authors.forename: Wonyong
authors.initials: W
authors.lastname: Kim
authors.forename: Soon Chul
authors.initials: SC
authors.lastname: Myung
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D011467:Prostate / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000032:analysis*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000175:diagnosis* / Q000188:drug therapy*; D012372:ROC Curve; D016896:Treatment Outcome; D036761:Ultrasound, High-Intensity Focused, Transrectal / Q000379:methods*
chemical_list: D017430:Prostate-Specific Antigen