title: Endorectal T2-weighted MRI does not differentiate between favorable and adverse pathologic features in men with prostate cancer who would qualify for active surveillance.
abstract: OBJECTIVE
  With the increased diagnosis of low grade, low volume, potentially non-lethal disease, active surveillance (AS) has become an increasingly popular alternative for select men with low-risk prostate cancer. The absence of precise clinical staging modalities currently makes it difficult to predict which patients are most appropriate for AS. The goal of our study was to evaluate the ability of endorectal MRI (eMRI) to predict adverse pathologic features in patients who would otherwise qualify for an AS program.
  
  
  METHODS
  We retrospectively reviewed our institution's radical prostatectomy (RP) database from 1991 to 2007 and identified 172 patients who would have qualified for AS and underwent preoperative staging eMRI with T2-weighted (T2W) sequences. MRI findings were correlated to final pathology in order to assess the ability of staging eMRI to predict adverse pathologic features in patients suitable for AS.
  
  
  RESULTS
  The mean age of our cohort was 59.8 ± 6.2 years. The mean PSA at the time of diagnosis was 5.2 ± 2.2 ng/ml. In 51% of patients, no discrete tumor was visualized on eMRI and in 49% of patients a discrete tumor was detected. At the time of RP, Gleason score upgrading, extracapsular extension, and a positive surgical margin occurred in 17%, 6%, and 5% of cases, respectively. Patients with documented tumor on eMRI did not have an increased incidence of adverse pathologic findings with regard to tumor volume (P = 0.31), extra-capsular extension (P = 0.82), Gleason upgrading (P = 0.92), seminal vesicle invasion (P = 0.97), or positive surgical margin rate (P = 0.95) compared with those in whom no tumor was seen.
  
  
  CONCLUSIONS
  Discrete tumor identification on eMRI is not predictive of adverse pathologic features in patients who would otherwise qualify for AS. eMRI likely does not provide additional information when prospectively evaluating patients for AS protocols.
authors.affiliation: Department of Surgery, Division of Urology, The Hospital of University of Pennsylvania, Philadelphia, PA, USA. tjguzzo@gmail.com
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Guzzo
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Resnick
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Canter
authors.forename: Trinity J
authors.initials: TJ
authors.lastname: Bivalacqua
authors.forename: Mark A
authors.initials: MA
authors.lastname: Rosen
authors.forename: Meredith R
authors.initials: MR
authors.lastname: Bergey
authors.forename: Laurie
authors.initials: L
authors.lastname: Magerfleisch
authors.forename: John E
authors.initials: JE
authors.lastname: Tomazewski
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Wein
authors.forename: S Bruce
authors.initials: SB
authors.lastname: Malkowicz
mesh_terms: D000368:Aged; D015331:Cohort Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000378:metabolism; D011468:Prostatectomy / Q000379:methods; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000473:pathology*; D012007:Rectum / Q000473:pathology; D012189:Retrospective Studies
chemical_list: D017430:Prostate-Specific Antigen