title: Preoperative assessment of prostate cancer using prebiopsy MRI.
abstract: OBJECTIVE
  The purpose of this article is to retrospectively evaluate the impact of prebiopsy MRI on preoperative assessment of prostate cancer.
  
  
  METHODS
  Between January 2005 and June 2012, 89 patients (mean age, 64 years; range, 50-77 years) underwent prebiopsy MRI, transrectal ultrasound-guided biopsy, and prostatectomy for adenocarcinoma. On MR images, prostate cancer was diagnosed if T2-weighted images, diffusion-weighted images, and dynamic contrast-enhanced images were all positive. Preoperative cancers were classified as low, intermediate, high, and very high risk using prostate-specific antigen (PSA) level, biopsy Gleason score, or MRI tumor stage. Postoperative cancers were classified as low, intermediate, high, and very high risk using PSA level, prostatectomy Gleason score, and prostatectomy tumor stage. Interrater agreement using weighted kappa values was used to compare the paired data.
  
  
  RESULTS
  Preoperative cancers assessed by PSA level alone and postoperative cancers were concordant in 24.7% (22/89) and discordant in 75.3% (67/89) of cases, with poor agreement (weighted κ, 0.13; 95% CI, 0.05-0.21). Preoperative cancers assessed by biopsy Gleason score alone and postoperative cancers were concordant in 40.4% (36/89) and discordant in 59.6% (53/89) of cases, with fair agreement (weighted κ, 0.22; 95% CI, 0.09-0.36). Preoperative cancers assessed by MRI tumor stage alone and postoperative cancers were concordant in 74.2% (66/89) and discordant in 25.8% (23/89) of cases, with moderate agreement (weighted κ, 0.54; 95% CI, 0.38-0.71).
  
  
  CONCLUSIONS
  Prebiopsy MRI may provide better information on preoperative assessment of prostate cancer than PSA level and biopsy Gleason score.
authors: 1 All authors: Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong Kangnam-ku, Seoul 135-710, Republic of Korea.
authors: Ji Hye
authors: JH
authors: Min
authors: Byung Kwan
authors: BK
authors: Park
authors: Jung Jae
authors: JJ
authors: Park
authors: Sung Yoon
authors: SY
authors: Park
authors: Chan Kyo
authors: CK
authors: Kim
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology* / Q000601:surgery; D000368:Aged; D003287:Contrast Media; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D017430:Prostate-Specific Antigen; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies; D020728:Transurethral Resection of Prostate
chemical_list: D003287:Contrast Media; D017430:Prostate-Specific Antigen
keywords: Gleason score; MRI; prostate cancer; prostate-specific antigen