Comparison of Initial Experience with Transrectal Magnetic Resonance Imaging Cognitive Guided Micro-Ultrasound Biopsies versus Established Transperineal Robotic Ultrasound Magnetic Resonance Imaging Fusion Biopsies for Prostate Cancer.

Abstract

We compared cancer detection rates in patients who underwent magnetic resonance imaging cognitive guided micro-ultrasound biopsy vs robotic ultrasound magnetic resonance imaging fusion biopsy for prostate cancer. Among 269 targeted biopsy procedures 222 men underwent robotic ultrasound magnetic resonance imaging fusion biopsy and 47 micro-ultrasound biopsy. Robotic ultrasound magnetic resonance imaging fusion biopsy was performed using the transperineal Artemis™ device while micro-ultrasound biopsy was performed transrectally with the high resolution ExactVu™ system. Random biopsies were performed in addition to targeted biopsy in both modalities. Prostate cancer detection rates and concordance between random and target biopsies were also assessed. Groups were comparable in terms of age, prostate specific antigen, prostate volume and magnetic resonance PI-RADS (Prostate Imaging Reporting and Data System) version 2 score. The micro-ultrasound biopsy group presented fewer biopsied cores in random and target approaches. In targeted biopsies micro-ultrasound biopsy cases presented higher detection of clinically significant disease (Gleason score greater than 6) than the robotic ultrasound magnetic resonance imaging fusion biopsy group (38% vs 23%, p=0.02). When considering prostate cancer detection regardless of Gleason score or prostate cancer detection by random+target biopsies, no difference was found between the groups. However, on a per core basis overall prostate cancer detection rates favored micro-ultrasound biopsy in random and targeted scenarios. In addition, the PRI-MUS (Prostate Risk Identification Using Micro-Ultrasound) score yielded by micro-ultrasound visualization was independently associated with improved cancer detection rates of clinically significant prostate cancer. In our initial experience micro-ultrasound biopsy featured a higher clinically significant prostate cancer detection rate in target cores than robotic ultrasound magnetic resonance imaging fusion biopsy, which was associated with target features in micro-ultrasound (PRI-MUS score). These findings reinforce the role of micro-ultrasound technology in targeted biopsies.