Comparison of conventional transrectal ultrasound, magnetic resonance imaging, and micro-ultrasound for visualizing prostate cancer in an active surveillance population: A feasibility study

  • Gregg Eure Urology of Virginia, Virginia Beach, Virginia
  • Daryl Fanney MRI & CT Diagnostics, Virginia Beach, Virginia
  • Jefferson Lin Urology of Virginia, Virginia Beach, Virginia
  • Brian Wodlinger Exact Imaging, Markham, Ontario
  • Sangeet Ghai Joint Department of Medical Imaging, University of Toronto, University Health Network - Mount Sinai Hospital-Women's College Hospital, Toronto General Hospital, Toronto, ON, Canada
Keywords: Prostate cancer, micro-ultrasound, MRI, PRI-MUS, PI-RADS, Active Surveillance

Abstract

Introduction: Active surveillance monitoring of prostate cancer is unique in that most patients have low-grade disease that is not well-visualized by any common imaging technique. High-resolution (29 MHz) micro-ultrasound is a new, real-time modality that has been demonstrated to be sensitive to significant prostate cancer and effective for biopsy targeting. This study compares micro-ultrasound imaging with magnetic resonance imaging (MRI) and conventional ultrasound for visualizing prostate cancer in active surveillance.

Methods: Nine patients on active surveillance were imaged with multiparametric (mp) MRI prior to biopsy. During the biopsy procedure, imaging and target identification was first performed using conventional ultrasound, then using micro-ultrasound. The mpMRI report was then unblinded and used to determine cognitive fusion targets. Using micro-ultrasound, biopsy samples were taken from targets in each modality, plus 12 systematic samples.

Results: mpMRI and micro-ultrasound both demonstrated superior sensitivity to Gleason sum 7 or higher cancer compared to conventional ultrasound (p=0.02 McNemar’s test). Micro-ultrasound detected 89% of clinically significant cancer, compared to 56% for mpMRI.

Conclusions: Micro-ultrasound may provide similar sensitivity to clinically significant prostate cancer as mpMRI and visualize all significant mpMRI targets. Unlike mpMRI, micro-ultrasound is performed in the office, in real-time during the biopsy procedure, and so is expected to maintain the cost-effectiveness of conventional ultrasound. Larger studies are needed before these results may be applied in a clinical setting.

Published
2018-08-30
How to Cite
Eure, G., Fanney, D., Lin, J., Wodlinger, B., & Ghai, S. (2018). Comparison of conventional transrectal ultrasound, magnetic resonance imaging, and micro-ultrasound for visualizing prostate cancer in an active surveillance population: A feasibility study. Canadian Urological Association Journal, 13(3). https://doi.org/10.5489/cuaj.5361
Section
Original Research