AUA 2020: Prostate Mapping for Cancer Diagnosis: The Madrid Protocol — Transperineal Prostate Biopsies Combining Micro-Ultrasound and mpMRI Fusion Biopsy

(UroToday.com) There has been rapid uptake in the use of multi-parametric magnetic resonance imaging (mpMRI) in the evaluation and diagnosis of patients at risk for prostate cancer. It is widely felt to be a useful tool that decreases rates of diagnosis of low-risk disease while increasing rates of diagnosis of clinically significant disease. However, it is not without downside including significant cost and the lack of real-time guidance of biopsy requiring fusion systems. In contrast, Micro-Ultrasound (Micro-US) is a high-resolution imaging approach, allowing real-time targeted biopsies. In a podium presentation at the American Urologic Association 2020 Virtual Annual Meeting, Dr. Moises Elias Rodriguez Socarras and colleagues present their work assessing transperineal prostate biopsy accuracy for prostate cancer detection combining Micro-US and mpMRI fusion biopsy during the same procedure.

The authors evaluated 200 consecutive patients who underwent transperineal prostate biopsies combining real-time targeted Micro-US (ExactVuTM) biopsies and mpMRI fusion biopsy in the same procedure between February 2018 and September 2019. Biopsies were performed using the PRIMUSTM Scale and a 3D printed TP guide attached to the 29MHz High-resolution Micro-US transducer.

The authors assessed demographic and clinicopathologic parameters including age, PSA, prostate volume, MRI lesions, prostate cancer diagnosis, clinically significant prostate cancer diagnosis (ISUP > 1), Gleason Group Grade (GG) and complications according to Clavien Dindo. Analysis was performed using McNeamar test and a Logistic Regression Model with p ≤ 0.05 was considered statistically significant.

Among 200 included patients, the median age was 63 years (IQR 58-69).

Prostate cancer was detected in 115 patients (57.5%) with clinically significant disease in 79 (39.5%). Micro-US and MRI together detected significantly more prostate cancer and clinically significant prostate cancer than systematic biopsy alone (p<0.001). No statistically significant difference was detected when comparing mpMRI biopsies vs targeted micro-US (p=0.24). However, 12 additional cases of prostate cancer were diagnosed on the basis of micro-US findings that were missed based on mpMRI-guided and systemic biopsy. Of these, 11 were clinically significant disease.

Both PI-RADS and PRI-MUS are strong predictors of csPCa in Logistic Regression Model (AUC for model with leave-one-out validation = 0.7).

PRI-MUS_PD48-12_AUA2020.png

Specifically, for PSA >4, PIRADS>3 there is an improvement in detection rate between PRI-MUS 4 and PRI-MUS 5 (36% GG>1 to 60% GG>1).

The authors conclude that, for men undergoing transperineal prostate biopsy, the use of combined Micro-ultrasound and mpMRI fusion biopsy increases yield of clinically significant prostate cancer.

Presented by: Moises Elias Rodriguez Socarras, Department of Urology, IRCCS San Raffaele Hospital, Ville Turro Division, Milan, Italy

Written by: Christopher J.D. Wallis, Urologic Oncology Fellow, Vanderbilt University Medical Center, Twitter: @WallisCJD, at the 2020 American Urological Association (AUA) Annual Meeting, Virtual Experience #AUA20, June 27- 28, 2020.