title: Evaluation of the European Society of Urogenital Radiology (ESUR) PI-RADS scoring system for assessment of extra-prostatic extension in prostatic carcinoma.
abstract: BACKGROUND
  To evaluate extra-prostatic extension (EPE) comparing PI-RADS to non-standardized reporting.
  
  
  METHODS
  With IRB approval, 145 consecutive patients underwent radical prostatectomy (RP) and multi-parametric (T2W+DWI+DCE) MRI between 2012 and 2013. Eighty patients (66.3% with EPE) were staged without PI-RADS and 65 patients (64.6% with EPE) were staged using a 5-point PI-RADS scoring system. Studies were reported by fellowship-trained radiologists in routine clinical practice. Individual PIRADS scores were assessed using ROC to determine the score which optimized sensitivity/specificity. Diagnostic accuracy for EPE was compared with/without PI-RADS using the McNemar test. Subgroup analysis by radiologist experience was performed using Spearman correlation and chi-square.
  
  
  RESULTS
  Area under ROC curve for EPE using PI-RADS was 0.62 and optimal sensitivity/specificity was achieved with PI-RADS score ≥ 3. Compared to non-standardized reporting, sensitivity for EPE improved with PI-RADS (59.5% [49.1-68.2] vs. 24.5% [16.7-31.2]), p=0.01; with no difference in specificity (68.0% [50.5-82.6]) vs. (75.0% [60.1-87.6]), p=0.06. Overall accuracy improved with PI-RADS (62.7% [49.6-73.6] vs. 42.0% [31.7-50.7%]), p=0.006. Diagnostic accuracy was better among experienced radiologists without PI-RADS (p=0.005); however, there was no difference in accuracy by reader experience using PI-RADS (p=0.24).
  
  
  CONCLUSIONS
  The PI-RADS criteria for EPE improves sensitivity without reducing specificity. PI-RADS may reduce differences in accuracy by reader experience.
authors.affiliation: The Ottawa Hospital, The University of Ottawa, Canada. Electronic address: nschieda@toh.on.ca.
authors.forename: Nicola
authors.initials: N
authors.lastname: Schieda
authors.affiliation: The Ottawa Hospital, The University of Ottawa, Canada. Electronic address: jquon@toh.on.ca.
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Quon
authors.affiliation: The Ottawa Hospital, The University of Ottawa, Canada. Electronic address: clim@toh.on.ca.
authors.forename: Christopher
authors.initials: C
authors.lastname: Lim
authors.affiliation: The Ottawa Hospital, The University of Ottawa, Canada. Electronic address: melkhodary@toh.on.ca.
authors.forename: Mohammed
authors.initials: M
authors.lastname: El-Khodary
authors.affiliation: The Ottawa Hospital, The University of Ottawa, Canada. Electronic address: wshabana@toh.on.ca.
authors.forename: Wael
authors.initials: W
authors.lastname: Shabana
authors.affiliation: The Ottawa Hospital, The University of Ottawa, Canada. Electronic address: vsingh@toh.on.ca.
authors.forename: Vivek
authors.initials: V
authors.lastname: Singh
authors.affiliation: The Ottawa Hospital, The University of Ottawa, Department of Surgery, Division of Urology, Canada. Electronic address: cmorash@toh.on.ca.
authors.forename: Christopher
authors.initials: C
authors.lastname: Morash
authors.affiliation: The Ottawa Hospital, The University of Ottawa, Department of Surgery, Division of Urology, Canada. Electronic address: rbreau@toh.on.ca.
authors.forename: Rodney H
authors.initials: RH
authors.lastname: Breau
authors.affiliation: The Ottawa Hospital, The University of Ottawa, Canada. Electronic address: mmcinnes@ottawahospital.on.ca.
authors.forename: Matthew D F
authors.initials: MD
authors.lastname: McInnes
authors.affiliation: The Ottawa Hospital, The University of Ottawa, Department of Anatomical Pathology, Canada. Electronic address: tflood@toh.on.ca.
authors.forename: Trevor A
authors.initials: TA
authors.lastname: Flood
mesh_terms: D000368:Aged; D019540:Area Under Curve; D002277:Carcinoma / Q000473:pathology* / Q000601:surgery; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging / Q000706:statistics & numerical data*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D011468:Prostatectomy / Q000379:methods; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000601:surgery; D012372:ROC Curve; D011871:Radiology / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media
keywords: Extra-prostatic extension; Magnetic resonance imaging; Prostate cancer; Prostate imaging reporting and data system PI-RADS; Staging