Performance of Combined Magnetic Resonance Imaging/Ultrasound Fusion-guided and Systematic Biopsy of the Prostate in Biopsy-naïve Patients and Patients with Prior Biopsies

Background: As recent prospective studies showed targeted biopsies (TBs) to be superior to systematic biopsies (SBs), magnetic resonance imaging (MRI) is gaining wider acceptance in the diagnostic setup of prostate cancer (PCa).

Objective: To examine the performance of MRI/ultrasound fusion-guided TB in combination with SB in the detection of PCa in patients with and without prior biopsy.

Design, setting, and participants: A total of 219 men undergoing combined transrectal TB and 12-core SB from February 2014 to November 2018 were analysed. For all patients showing a suspicion of PCa in multiparametric MRI, TB was performed using fusion imaging with real-time virtual sonography.

Outcome measurements and statistical analysis: Cancer detection rates (CDRs) and significant CDRs for TB, SB, and TB+SB were analysed. Further stratification was performed for a number of previous biopsy sessions and Prostate Imaging Reporting and Data System (PI-RADS) score. Significant PCa was defined as any PCa with Gleason score ≥3+4.

Results and limitations: Of all, 141 patients were biopsy naïve, while 78 patients had at least one prior biopsy. Median prostate-specific antigen (PSA) level prior to biopsy was 8.4ng/ml (interquartile range 5.5-11.8ng/ml). The overall CDR was 63.5% (139/219), while the PI-RADS-dependent CDRs for the combination of TB+SB were 29.1%, 67.7%, and 86.2% for patients with PI-RADS 3, 4, and 5, respectively. Looking at TB or SB alone, CDRs were 55.7% and 57.5%. The overall CDR for significant PCa was 51.6%. (18.2%, 50.5%, and 81.5% for PI-RADS 3, 4, and 5, respectively). CDRs were significantly higher for biopsy-naïve patients (65.2% vs 67.4% vs 71.6% for TB vs SB vs TB+SB) than for patients with one previous negative biopsy (38.2% vs 43.6% vs 50.9% for TB vs SB vs TB+SB; all p<0.01).

Conclusions: Multiparametric MRI can raise the CDR in patients with and without biopsies performed earlier. With higher PI-RADS lesions, the risk of harbouring PCa increases. Combining TB with SB further improved the diagnostic accuracy in biopsy-naïve patients and after one previous negative biopsy.

Patient summary: Multiparametric magnetic resonance imaging before prostate biopsy increases cancer detection rates in biopsy-naïve patients and patients with a previous negative biopsy. The combination of targeted biopsy with systematic biopsy improved the diagnostic accuracy in biopsy-naïve patients and after one previous negative biopsy.