title: The Prevalence of Clinically Significant Prostate Cancer According to Commonly Used Histological Thresholds in Men Undergoing Template Prostate Mapping Biopsies.
abstract: OBJECTIVE
  Transrectal prostate biopsies are inaccurate and, thus, the prevalence of clinically significant prostate cancer in men undergoing biopsy is unknown. We determined the ability of different histological thresholds to denote clinically significant cancer in men undergoing a more accurate biopsy, that of transperineal template prostate mapping.
  
  
  METHODS
  In this multicenter, cross-sectional cohort of men who underwent template prostate mapping biopsies between May 2006 and January 2012, 4 different thresholds of significance combining tumor grade and burden were used to measure the consequent variation with respect to the prevalence of clinically significant disease.
  
  
  RESULTS
  Of 1,203 men 17% (199) had no previous biopsy, 38% (455) had a prior negative transrectal ultrasound biopsy, 24% (289) were on active surveillance and 21% (260) were seeking risk stratification. Mean patient age was 63.5 years (SD 7.6) and median prostate specific antigen was 7.4 ng/ml (IQR 5.3-10.5). Overall 35% of the patients (424) had no cancer detected. The prevalence of clinically significant cancer varied between 14% and 83% according to the histological threshold used, in particular between 30% and 51% among men who had no previous biopsy, between 14% and 27% among men who had a prior negative biopsy, between 36% and 74% among men on active surveillance, and between 47% and 83% among men seeking risk stratification.
  
  
  CONCLUSIONS
  According to template prostate mapping biopsy between 1 in 2 and 1 in 3 men have prostate cancer that is histologically defined as clinically significant. This suggests that the commonly used thresholds may be set too low.
authors.affiliation: Division of Surgery and Interventional Science, University College London, London, United Kingdom; Department of Urology, University College Hospitals NHS Foundation Trust, London, United Kingdom; Department of Urology, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland. Electronic address: massimo.valerio.12@ucl.ac.uk.
authors.forename: M
authors.initials: M
authors.lastname: Valerio
authors.affiliation: Division of Surgery and Interventional Science, University College London, London, United Kingdom; Department of Urology, University College Hospitals NHS Foundation Trust, London, United Kingdom.
authors.forename: C
authors.initials: C
authors.lastname: Anele
authors.affiliation: Department of Urology, Frimley Park Hospital NHS Foundation Trust, Frimley, United Kingdom.
authors.forename: S R J
authors.initials: SRJ
authors.lastname: Bott
authors.affiliation: Department of Health Services Research and Policy, London School of Hygiene and Tropical Medicine, London, United Kingdom.
authors.forename: S C
authors.initials: SC
authors.lastname: Charman
authors.affiliation: Department of Health Services Research and Policy, London School of Hygiene and Tropical Medicine, London, United Kingdom.
authors.forename: J
authors.initials: J
authors.lastname: van der Meulen
authors.affiliation: Department of Histopathology, Basingstoke and North Hampshire NHS Foundation Trust, Basingstoke, Hampshire, United Kingdom.
authors.forename: H
authors.initials: H
authors.lastname: El-Mahallawi
authors.affiliation: Department of Urology, Basingstoke and North Hampshire NHS Foundation Trust, Basingstoke, Hampshire, United Kingdom; Department of Urology, Ain Shams University, Cairo, Egypt.
authors.forename: A M
authors.initials: AM
authors.lastname: Emara
authors.affiliation: Department of Histopathology, University College Hospital London, London, United Kingdom.
authors.forename: A
authors.initials: A
authors.lastname: Freeman
authors.affiliation: Department of Histopathology, University College Hospital London, London, United Kingdom.
authors.forename: C
authors.initials: C
authors.lastname: Jameson
authors.affiliation: Department of Urology, Basingstoke and North Hampshire NHS Foundation Trust, Basingstoke, Hampshire, United Kingdom.
authors.forename: R G
authors.initials: RG
authors.lastname: Hindley
authors.affiliation: Department of Urology, Frimley Park Hospital NHS Foundation Trust, Frimley, United Kingdom.
authors.forename: B S I
authors.initials: BSI
authors.lastname: Montgomery
authors.affiliation: Department of Urology, Royal Free London NHS Foundation Trust, London, United Kingdom.
authors.forename: P B
authors.initials: PB
authors.lastname: Singh
authors.affiliation: Division of Surgery and Interventional Science, University College London, London, United Kingdom; Department of Urology, University College Hospitals NHS Foundation Trust, London, United Kingdom.
authors.forename: H U
authors.initials: HU
authors.lastname: Ahmed
authors.affiliation: Division of Surgery and Interventional Science, University College London, London, United Kingdom; Department of Urology, University College Hospitals NHS Foundation Trust, London, United Kingdom.
authors.forename: M
authors.initials: M
authors.lastname: Emberton
mesh_terms: D000368:Aged; D001707:Biopsy, Needle / Q000295:instrumentation*; D003430:Cross-Sectional Studies; D004534:Egypt / Q000453:epidemiology; D004867:Equipment Design; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011467:Prostate / Q000473:pathology*; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000453:epidemiology*; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods*; D013557:Switzerland / Q000453:epidemiology; D006113:United Kingdom / Q000453:epidemiology
keywords: biopsy; prevalence; prostatic neoplasms; risk assessment