A Prospective Comparison of Selective Multiparametric Magnetic Resonance Imaging Fusion-Targeted and Systematic Transrectal Ultrasound-Guided Biopsies for Detecting Prostate Cancer in Men Undergoing Repeated Biopsies

Abstract

Introduction: The aim of the study was to compare the prostate cancer (PCa) detection rate of systematic transrectal ultrasound-guided biopsies (TRUS-bx) and multiparametric-MRI targeted biopsies (mp-MRI-bx) in a repeat biopsy setting and evaluate the clinical significance following an "MRI-targeted-only" approach.

Materials and methods: Patients with prior negative biopsies underwent prostatic multiparametric-MRI that was scored using the Prostate Imaging Reporting and Data System (PI-RADS) classification. All underwent both repeated TRUS-bx and mp-MRI-bx using image fusion of any PI-RADS ≥3 lesion. Biopsy results from TRUS-bx, mp-MRI-bx, and the combination were compared.

Results: PCa was detected in 89 out of 206 (43%) patients. Of these, 64 (31%) and 74 (36%) patients were detected using mp-MRI-bx and TRUS-bx, respectively. Overall, mp-MRI-bx detected fewer patients with low-grade (Gleason score [GS] 3 + 3) cancers (14/64 vs. 41/74) and more patients with intermediate/high-grade cancers (GS ≥3 + 4) (50/64 vs. 33/74) using fewer biopsy cores compared with TRUS-bx (p < 0.001). Using an "MRI-targeted-only" approach in men with PI-RADS ≥3 lesions reduced the number of men requiring repeated biopsies by 50%, decreased low-grade cancer diagnoses by 66%, and increased intermediate/high-grade cancer diagnoses by 52%.

Conclusions: MRI-targeted biopsies have a high detection rate for significant PCa in patients with prior negative transrectal ultrasound-guided biopsies and preferentially detect intermediate/high-grade compared with low-grade tumors.

Keywords: Biopsy; Magnetic resonance imaging; Outcome; Prostate cancer; Ultrasonography.