title: The effect of sampling more cores on the predictive accuracy of pathological grade and tumour distribution in the prostate biopsy.
abstract: OBJECTIVE
  To determine if increasing the number of cores at biopsy improves the predictive accuracy of the Gleason score or aids in anticipating the location and volume of prostate tumour.
  
  
  METHODS
  The charts of 75 consecutive patients who underwent radical retropubic prostatectomy for clinical T1-2 adenocarcinoma of the prostate were reviewed retrospectively; 31 patients had a sextant biopsy (group 1) and 44 had > or = 8 cores taken (group 2). The concordance between biopsy data and final prostatectomy Gleason score, tumour location and volume was determined for each group.
  
  
  RESULTS
  There were no differences in mean age, prostate-specific antigen level before biopsy or biopsy Gleason score for the two groups; 58% of group 1 had their final pathological grade changed after prostatectomy, vs 29% of group 2 (P < 0.05). In neither group was there a significant correlation between the percentage of cores positive for tumour and the percentage volume of prostate involved with cancer, or the ability of the biopsy to predict tumour location.
  
  
  CONCLUSIONS
  Taking > or = 8 biopsy cores improved the pathological grading accuracy, which may be valuable in choosing a treatment for the patient with newly diagnosed prostate cancer.
authors.affiliation: Department of Urology, University of Virginia Health Sciences Center, Charlottesville, Virginia 22908, USA.
authors.forename: A A
authors.initials: AA
authors.lastname: Makhlouf
authors.forename: T L
authors.initials: TL
authors.lastname: Krupski
authors.forename: D
authors.initials: D
authors.lastname: Kunkle
authors.forename: D
authors.initials: D
authors.lastname: Theodorescu
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology* / Q000601:surgery; D001707:Biopsy, Needle / Q000379:methods / Q000592:standards; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011467:Prostate / Q000473:pathology*; D011468:Prostatectomy / Q000379:methods; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies; D012680:Sensitivity and Specificity