title: Multiparametric magnetic resonance imaging enhances detection of significant tumor in patients on active surveillance for prostate cancer.
abstract: OBJECTIVE
  To determine whether multiparametric magnetic resonance imaging (MRI) of the prostate (mpMRI) combined with MRI fusion technology during transrectal ultrasound-guided biopsy can enhance the detection of significant disease in patients with apparent low-risk prostate cancer on active surveillance (AS).
  
  
  METHODS
  We reviewed the charts of 603 patients on AS for localized prostate cancer between January 2006 and September 2013. mpMRI before repeat transrectal ultrasound-guided biopsy was obtained in 111 patients, of whom 69 underwent subsequent fusion biopsy (39 true and 30 cognitive) in addition to standard template biopsy. The results of fusion biopsy were compared with the standard biopsy. The primary endpoint was termination of AS.
  
  
  RESULTS
  mpMRI detected 118 suspicious lesions in 70 patients (63%). Of these, 42 patients (60%) had lesions with Prostate imaging, reporting, and data system (PIRADS) score 3, and 28 patients (40%) had PIRADS score 4 or 5 lesions. AS was terminated in 27 (24.3%) of the 111 patients who underwent mpMRI. Seventeen patients stopped AS based on mpMRI findings including 16 for pathologic progression in target biopsies and 1 for lesion size increase, whereas the other 10 stopped AS because of pathologic progression in the standard cores (n = 6) or other reasons (n = 4). Use of mpMRI increased the rate of AS termination (27 vs. 10; P = .002). On multivariate analysis, PIRADS score 4-5 (vs. 3) was the only significant predictor of AS termination (P = .015).
  
  
  CONCLUSIONS
  These preliminary retrospective findings suggest that mpMRI with subsequent fusion biopsy enhances the identification of AS patients requiring definitive treatment.
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Hamidreza
authors.initials: H
authors.lastname: Abdi
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Farshad
authors.initials: F
authors.lastname: Pourmalek
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Homayoun
authors.initials: H
authors.lastname: Zargar
authors.affiliation: Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Triona
authors.initials: T
authors.lastname: Walshe
authors.affiliation: Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Alison C
authors.initials: AC
authors.lastname: Harris
authors.affiliation: Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Silvia D
authors.initials: SD
authors.lastname: Chang
authors.affiliation: Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Christopher
authors.initials: C
authors.lastname: Eddy
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Alan I
authors.initials: AI
authors.lastname: So
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Martin E
authors.initials: ME
authors.lastname: Gleave
authors.affiliation: Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Lindsay
authors.initials: L
authors.lastname: Machan
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: S Larry
authors.initials: SL
authors.lastname: Goldenberg
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, British Columbia, Canada. Electronic address: pblack@mail.ubc.ca.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Black
mesh_terms: D000368:Aged; D006801:Humans; D061705:Image-Guided Biopsy; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D012189:Retrospective Studies; D018084:Ultrasonography, Interventional; D057832:Watchful Waiting