title: Multiparametric magnetic resonance imaging localizes established extracapsular extension of prostate cancer.
abstract: OBJECTIVE
  To define the accuracy of multiparametric magnetic resonance imaging (MP-MRI) for identifying focal and established extracapsular extension (ECE) in various zones of the prostate.
  
  
  METHODS
  Between 2010 and 2013, 342 patients underwent MP-MRI of the prostate (3T, no endorectal coil with axial perfusion and diffusion images). The findings of the images were reported as negative, suspicious, or positive for ECE by a single expert radiologist. Radical prostatectomy specimens were reviewed to confirm the size and the location of ECE and further defined as focal or established ECE. Established ECE included extension that was multifocal or involving more than 5 glands. The accuracy of MRI in localizing focal and established ECE to each zone of the prostate was determined. Regression analyses were performed to identify predictors of ECE.
  
  
  RESULTS
  We identified 112 patients who underwent prostate MP-MRI and radical prostatectomy. MRI findings considered suspicious or definite for ECE accurately predicted pathologic ECE (P<0.001). MP-MRI identified established ECE but not focal ECE. Sensitivity, specificity, positive predictive value, and negative predictive value of MP-MRI for established ECE were 70.7%, 90.6%, 57.1%, and 95.1%, respectively. MRI identified ECE to the left vs. right side as well as each zone of the prostate; however, sensitivity was lowest at the apex. On multivariate analysis, MRI was a significant predictor of ECE that was independent of prostate-specific antigen level, Gleason score, and clinical stage.
  
  
  CONCLUSIONS
  MP-MRI is useful for identifying established but not focal ECE in all zones of the prostate. MRI was a significant independent predictor of established ECE and may be a useful adjunct in staging prostate cancer.
authors.affiliation: Division of Urology, Cedars-Sinai Medical Center, Los Angeles, CA.
authors.forename: Tom S
authors.initials: TS
authors.lastname: Feng
authors.affiliation: Division of Urology, Cedars-Sinai Medical Center, Los Angeles, CA.
authors.forename: Ali Reza
authors.initials: AR
authors.lastname: Sharif-Afshar
authors.affiliation: Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA.
authors.forename: Steven C
authors.initials: SC
authors.lastname: Smith
authors.affiliation: Department of Radiology, Cedars-Sinai Medical Center, Los Angeles, CA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Miller
authors.affiliation: Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Nguyen
authors.affiliation: Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA.
authors.forename: Quanlin
authors.initials: Q
authors.lastname: Li
authors.affiliation: Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, CA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Luthringer
authors.affiliation: Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA.
authors.forename: Debiao
authors.initials: D
authors.lastname: Li
authors.affiliation: Department of Radiology, Cedars-Sinai Medical Center, Los Angeles, CA.
authors.forename: Rola
authors.initials: R
authors.lastname: Saouaf
authors.affiliation: Division of Urology, Cedars-Sinai Medical Center, Los Angeles, CA. Electronic address: KimHL@cshs.org.
authors.forename: Hyung L
authors.initials: HL
authors.lastname: Kim
mesh_terms: D000368:Aged; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D011467:Prostate / Q000473:pathology*; D017430:Prostate-Specific Antigen / Q000378:metabolism; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery*; D012372:ROC Curve; D012044:Regression Analysis; D015203:Reproducibility of Results; D012669:Seminal Vesicles / Q000473:pathology
chemical_list: D017430:Prostate-Specific Antigen
keywords: Cancer staging; Extracapsular extension; Magnetic resonance imaging; Prostate cancer