Purpose: 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.
Materials and methods: 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.
Results: 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.
Conclusions: 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.
Keywords: biopsy; high-intensity focused; magnetic resonance imaging; prostatic neoplasms; transrectal; ultrasound.