EAU 2019: The Role of (fast) Bi-Parametric MRI versus Multi-Parametric MRI and TRUS-biopsy for Detecting Clinically Significant Prostate Cancer in Biopsy Naïve Men with Elevated PSA

Barcelona, Spain (UroToday.com) Professor Barentsz presented his group’s work assessing fast bi-parametric MRI for detection of prostate cancer. As Dr. Barentsz notes, we have three level 1a prospective clinical trials concluding that we should be doing an MRI before biopsy1-3. This is now reflected in the EAU guidelines, noting in biopsy naïve patients:

  • Perform mpMRI before prostate biopsy (1a, weak)
  • When mpMRI is positive (ie. PI-RADS ≥3), combine targeted and systematic biopsies (2a, strong)
  • When mpMRI is negative (ie. PI-RADS ≤2), and clinical suspicion of prostate cancer is low, omit biopsy based on shared decision making with the patient (2a, weak)
A mpMRI is comprised of an injection of contrast, ADC images, T2W images, DCE images; these are obtained in sagittal, coronal and axial planes allowing ~2 studies per hour to be performed in the MRI suite. A bi-parametric MRI removes the DCE images by eliminating contrast injection allowing ~3 to be performed per hour. A fast bi-parametric MRI is a bi-parametric MRI without the T2W sagittal and coronal views (ie. only axial), thus allowing 4 MRIs per hour. 

EAU2019 UroToday fast bpMRI


The aim of the current study was to compare mono-planar “fast” bpMRI, tri-planar bpMRI and mpMRI. This cohort was a subgroup of the 626 patients in the 4M prospective, multi-center, head-to-head trial3. The reference standard was the results of a systematic biopsy and in-bore MR-guided biopsy, as well as a PI-RADS score from the mpMRI (prior to fast bpMRI).

Dr. Barentsz group found that the fast bpMRI group had an 11% rate of PI-RADS 3 compared to 6% in the mpMRI group. Between the three arms (fast bpMRI, bpMRI, mpMRI), there was no difference in detection of clinically significant prostate cancer (sensitivity 95%); fast bpMRI resulted in a 2% increase in the number of men receiving a biopsy. Specificity was 69% in the mpMRI group and 66% in the fast bpMRI group.

Dr. Barentsz notes that there are several pros for fast bpMRI:
  • The ability to perform 4 fast bpMRIs per hour
  • There is a 54% decrease in direct costs, however, the total cost (secondary to increased biopsies and overdiagnosis) equalizes the cost savings
  • There is no contrast given, thus eliminating the risk of an allergic reaction or Gadolinium-brain deposition
However, there are several cons/limitations to fast bpMRI:
  • A 5% absolute increase in PI-RADS 3 lesions (6% vs 11%); however, PRECISION [2] had 7%
  • A 2% absolute increase in the number of biopsies (51% vs 53%)
  • A 1% absolute increase in clinically insignificant prostate cancer (13% vs 12%); however, TRUS systematic biopsy has 23%
  • No histology from mpMRI negative lesions
  • The systematic biopsy as positive was the reference standard
  • Expert center: limited generalizability
Dr. Barentsz concluded that fast bpMRI has equal detection rate for clinically significant prostate cancer and can be fast, non-invasive, accurate and less expensive. He foresees a possible PSA-MRI screening modality that he has termed the mannogram:
EAU2019 UroToday mannogram


Presented by: Jelle Barentsz, MD, PhD, Radboudumc, Nijmegen, The Netherlands

Written by: Zachary Klaassen, MD, MSc – Assistant Professor of Urology, Georgia Cancer Center, Augusta University - Medical College of Georgia Twitter: @zklaassen_md at the 34th European Association of Urology (EAU 2019) #EAU19 conference in Barcelona, Spain, March 15-19, 2019.

References:
  1. Rouviere O, Renard-Penna R, Claudon M, et al. Use of prostate systematic and targeted biopsy on the basis of multiparametric MRI in biopsy-naïve patients (MRI-FIRST): A prospective, multicentre, paired diagnostic study. Lancet Oncol 2019 Jan;20(1):100-109.
  2. Kasivisvanathan V, Rannikko AS, Borghi M, et al. MRI-targeted or standard biopsy for prostate cancer diagnosis. N Engl J Med 2018;378(19):1767-1777.
  3. van der Leest M, Cornel E, Israel B, et al. Head-to-head comparison of transrectal ultrasound-guided prostate versus multiparametric prostate resonance imaging with subsequent magnetic resonance-guided biopsy in biopsy-naïve men with elevated prostate-specific antigen: A Large Prospective multicenter study. Eur Urol. 2018 Nov 23 [Epub ahead of print].
Further Related Content:
Read the Discussion on this Presentation by Dr. Alberto Briganti 
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