Outcomes of Multi-parametric MRI-US Cognitive Fusion Template-guided Transperineal Prostate Biopsy: A Single Centre Experience

Abstract

Aims: The aim of this study was to report the outcomes of multiparametric Magnetic Resonance Imaging-Ultrasound (mpMRI-US) cognitive fusion template-guided transperineal prostate biopsy (TPB) performed in a single tertiary institution. Study Design:  Retrospective. Place and Duration of Study: Sample: Department of Urology, Kuala Lumpur General Hospital, between April 2017 and December 2019. Methodology: Patients with Prostate Imaging-Reporting and Data System (PI-RADS) 3-5 on mpMRI who underwent cognitive mpMRI-US fusion template-guided TPB were recruited retrospectively. Data was analyzed to determine prostate cancer (PCa) detection rate, diagnostic accuracy of mpMRI and post-TPB complication rates. Clinically significant PCa (csPCa) was defined as Gleason ≥3+4. Results: 122 patients were enrolled and 330 PI-RADS 3-5 lesions were analyzed. The mean age was 66, mean prostate specific antigen was 15.5 ng/mL and mean number of biopsy cores was 56.6. 54.1% were Chinese, 38.5% were Malays, 4.9% were Indian and 2.5% were Others. There were 3 subgroups: repeat biopsy (70.5%), biopsy naïve (21.3%) and re-staging (8.2%). The detection rate of overall PCa and csPCa was 43.4% and 24.6% respectively. csPCa was detected in 43.8%, 48.6% and 66.7% in PI-RADS 3, 4 and 5 respectively. mpMRI missed 19.4% of PCa, of these 66.7% was Gleason 6. 50% patients on active surveillance had disease upstaged. For csPCa detection, mpMRI had a sensitivity of 87%, specificity of 86.1%, positive predictive value of 13.1% and negative predictive value of 99.6%. On multivariate analysis, age (P < .001), Indian race (P = .007) and prostate volume (P < .001) were statistically significant. The complication rate was low (acute urinary retention 4.9%, hematuria 9%, infection 0.8%) and mortality was zero. Conclusion: mpMRI plays a major role in diagnosing csPCa. The higher the PI-RADS, the more csPCa was detected. Our experience with cognitive MRI-US fusion template-guided TPB yield a consistent result with other studies in terms of overall PCa detection, rate of low-grade PCa in ‘missed’ lesions in mpMRI, correlation between PCa detection and larger prostate size and comparable diagnostic accuracy of mpMRI. We also reported a high diagnostic accuracy of mpMRI in PCa detection and low complication rates of TPB.