title: Localising prostate cancer: comparison of endorectal magnetic resonance (MR) imaging and 3D-MR spectroscopic imaging with transrectal ultrasound-guided biopsy.
abstract: BACKGROUND
  Magnetic resonance imaging (MRI) and MR spectroscopic imaging (MRSI) have been gaining acceptance as tools in the evaluation of prostate cancer. We compared the accuracy of transrectal ultrasound (TRUS)-guided biopsy and dynamic contrast-enhanced MRI combined with three-dimensional (3D) MRSI in locating prostate tumours and determined the influence of prostate weight on MRI accuracy.
  
  
  METHODS
  Between March 1999 and October 2006, 507 patients with localised prostate cancer underwent radical prostatectomy (RP) at the Jules Bordet Institute. Of these, 220 had undergone endorectal MRI (1.5 T Siemens Quantum Symphony) and 3D-MRSI prior to RP. We retrospectively reviewed data on tumour location and compared the results obtained by MRI and by TRUS-guided biopsy with those obtained on histopathology of the RP specimen.
  
  
  RESULTS
  Patient data were as follows: median age 62.4 years (45-74); median PSA 6.36 ng/ml (0.5-22.6); 73.6% of patients had non-palpable disease (T1c); median biopsy Gleason score 6 (3-9); median RP specimen weight 50 g (12-172); median pathological Gleason score 7 (4-10); 68.64% of patients had organ-confined (pT2) disease. Tumour localisation was correlated with RP data in a significantly higher percentage of patients when using MRI rather than TRUS-guided biopsy (47.4 vs. 36.6%, p < 0.0001). MRI was marginally superior to TRUS-guided biopsy in detecting malignancy at the prostate apex (48.3 vs. 41.9%, p = 0.0687) and somewhat better at the prostate base (46 vs. 39.1%, p = 0.0413). It was highly significantly better at mid-gland (52 vs. 41.1%, p = 0.0015) and in the transition zone (40.1 vs. 24.3%, p < 0.0001). MRI had higher sensitivity in larger (≥50 g) than smaller (<50 g) prostates (50.3 vs. 42.2%, p = 0.0017).
  
  
  CONCLUSIONS
  MRI was superior to TRUS-guided biopsy in locating prostate tumours except at the gland apex. MRI was more accurate in larger (≥50 g) than smaller prostates.
authors: Department of Urology, Institut Jules Bordet, Brussels, Belgium.
authors: Maximilien C
authors: MC
authors: Goris Gbenou
authors: Alexandre
authors: A
authors: Peltier
authors: Sanjai K
authors: SK
authors: Addla
authors: Marc
authors: M
authors: Lemort
authors: Renaud
authors: R
authors: Bollens
authors: Denis
authors: D
authors: Larsimont
authors: Thierry
authors: T
authors: Roumeguère
authors: Claude C
authors: CC
authors: Schulman
authors: Roland
authors: R
authors: van Velthoven
mesh_terms: D000368:Aged; D001530:Belgium; D001706:Biopsy; D016009:Chi-Square Distribution; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D009929:Organ Size; D011237:Predictive Value of Tests; D011379:Prognosis; D011467:Prostate / Q000473:pathology* / Q000601:surgery; D017430:Prostate-Specific Antigen / Q000097:blood; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D018084:Ultrasonography, Interventional
chemical_list: D017430:Prostate-Specific Antigen