title: Measurement of serum isoform [-2]proPSA derivatives shows superior accuracy to magnetic resonance imaging in the diagnosis of prostate cancer in patients with a total prostate-specific antigen level of 2-10 ng/ml.
abstract: OBJECTIVE
  More accurate diagnostic procedures for prostate cancer are needed to avoid unnecessary biopsy due to the low specificity of prostate-specific antigen (PSA). Recent studies showed that the percentage of serum isoform [-2]proPSA (p2PSA) to free PSA (%p2PSA), the Prostate Health Index (PHI) and magnetic resonance imaging (MRI) were more accurate than PSA. The aim of this study was to test the accuracy of %p2PSA, PHI and MRI in discriminating patients with and without prostate cancer.
  
  
  METHODS
  The subjects were 50 consecutive men with a PSA level of 2.0-10.0 ng/ml, who underwent prostate biopsy from October 2012 to July 2014. These patients underwent multiparametric MRI before biopsy, and their serum samples were measured for PSA, free PSA and p2PSA. The sensitivity, specificity and accuracy of PHI, %p2PSA and MRI were compared with PSA in the diagnosis of biopsy-confirmed prostate cancer.
  
  
  RESULTS
  In a univariate analysis, %p2PSA [area under the curve (AUC): 0.811] and PHI (AUC 0.795) were more accurate than MRI (AUC: 0.583) and PSA (AUC: 0.554) for prostate cancer detection. At 60% sensitivity, the specificity of PHI (76.5%) was higher than that of MRI (52.9%). For significant cancer detection, %p2PSA (AUC: 0.745), PHI (AUC: 0.791) and MRI (AUC: 0.739) were marginally more accurate than PSA (AUC: 0.696). At 85% sensitivity, the specificity of MRI (62.1%) was higher than that of PHI (34.5%).
  
  
  CONCLUSIONS
  PHI and %p2PSA can be used for screening the general population and MRI can be used for detection of significant cancer in patients suspected, from screening tests, of having prostate cancer.
authors.affiliation: a Department of Urology , Graduate School of Medicine, Yokohama City University , Yokohama , Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Furuya
authors.affiliation: b Department of Urology , Yokohama City University Medical Center , Yokohama , Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kawahara
authors.affiliation: b Department of Urology , Yokohama City University Medical Center , Yokohama , Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Narahara
authors.affiliation: a Department of Urology , Graduate School of Medicine, Yokohama City University , Yokohama , Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Tokita
authors.affiliation: a Department of Urology , Graduate School of Medicine, Yokohama City University , Yokohama , Japan.
authors.forename: Sachi
authors.initials: S
authors.lastname: Fukui
authors.affiliation: a Department of Urology , Graduate School of Medicine, Yokohama City University , Yokohama , Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Imano
authors.affiliation: a Department of Urology , Graduate School of Medicine, Yokohama City University , Yokohama , Japan.
authors.forename: Taku
authors.initials: T
authors.lastname: Mitome
authors.affiliation: a Department of Urology , Graduate School of Medicine, Yokohama City University , Yokohama , Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Ito
authors.affiliation: a Department of Urology , Graduate School of Medicine, Yokohama City University , Yokohama , Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Izumi
authors.affiliation: a Department of Urology , Graduate School of Medicine, Yokohama City University , Yokohama , Japan.
authors.forename: Kimito
authors.initials: K
authors.lastname: Osaka
authors.affiliation: a Department of Urology , Graduate School of Medicine, Yokohama City University , Yokohama , Japan.
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Yokomizo
authors.affiliation: a Department of Urology , Graduate School of Medicine, Yokohama City University , Yokohama , Japan.
authors.forename: Narihiko
authors.initials: N
authors.lastname: Hayashi
authors.affiliation: a Department of Urology , Graduate School of Medicine, Yokohama City University , Yokohama , Japan.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Hasumi
authors.affiliation: c Department of Radiology , Graduate School of Medicine, Yokohama City University , Yokohama , Japan.
authors.forename: Shintaro
authors.initials: S
authors.lastname: Nawata
authors.affiliation: c Department of Radiology , Graduate School of Medicine, Yokohama City University , Yokohama , Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Kawano
authors.affiliation: a Department of Urology , Graduate School of Medicine, Yokohama City University , Yokohama , Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yao
authors.affiliation: b Department of Urology , Yokohama City University Medical Center , Yokohama , Japan.
authors.forename: Hiroji
authors.initials: H
authors.lastname: Uemura
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D001706:Biopsy; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011467:Prostate / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000473:pathology*; D020033:Protein Isoforms / Q000097:blood; D011498:Protein Precursors / Q000097:blood*; D012372:ROC Curve; D012189:Retrospective Studies
chemical_list: C583834:(-2)pro-prostate-specific antigen, human; D020033:Protein Isoforms; D011498:Protein Precursors; D017430:Prostate-Specific Antigen
keywords: %p2PSA; Biopsy; MRI; PSA; Prostate Health Index; detection; proPSA; prostate cancer