Diagnostic Accuracy of Multiparametric Magnetic Resonance Imaging to Detect Residual Prostate Cancer Following Irreversible Electroporation-A Multicenter Validation Study.

Accurate monitoring following focal treatment of prostate cancer (PCa) is paramount for timely salvage treatment or retreatment.

To evaluate the diagnostic accuracy of multiparametric magnetic resonance imaging (mpMRI) to detect residual PCa in the short-term follow-up of focal treatment with irreversible electroporation (IRE) using transperineal or transrectal template ± targeted biopsies.

A retrospective international multicenter study of men with biopsy-proven PCa, treated with focal IRE, and followed by mpMRI (index-test) and template biopsies (reference-test) between February 2013 and January 2021, was conducted.

Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of mpMRI were calculated for in- and outfield residual disease based on two definitions of significant PCa: University College London (UCL) 1-International Society of Urological Pathology (ISUP) ≥3 or ISUP ≥1 with maximum cancer core length (MCCL) ≥6 mm, and UCL2-ISUP ≥2 or ISUP ≥1 with MCCL ≥4 mm.

A total of 303 patients from five focal therapy centers were treated with primary IRE. The final analysis was performed on 217 men (median age 67, median prostate-specific antigen 6.2, 81% ISUP 2/3) who underwent both mpMRI and template biopsies. Multiparametric MRI missed 38/57 (67%) positive biopsy locations (UCL1) in 22 patients. Sensitivity, specificity, PPV, and NPV of mpMRI to detect whole gland residual disease (UCL1) were 43.6% (95% confidence interval [CI]: 28-59), 80.9% (95% CI: 75-86), 33.3% (95% CI: 21-47), and 86.7% (95% CI: 81-91), respectively. Based on UCL2, sensitivity, specificity, PPV, and NPV were 35.8% (95% CI: 25-48), 82.0% (95% CI: 75-88), 47.1% (95% CI: 34-61), and 74.1% (95% CI: 67-80), respectively. Limitations are the retrospective nature and short follow-up.

The diagnostic accuracy of mpMRI to detect residual clinically significant PCa following IRE was low. Follow-up template biopsies should be performed, regardless of mpMRI results.

We investigated the accuracy of magnetic resonance imaging (MRI) to detect residual prostate cancer after treatment with irreversible electroporation. The accuracy of MRI is insufficient, and we emphasize the importance of confirmatory prostate biopsies.

European urology focus. 2022 May 13 [Epub ahead of print]

Bart Geboers, William Gondoputro, James E Thompson, Daan J Reesink, Luigi A M J G van Riel, David Zhang, Alexandar Blazevski, Paul Doan, Shikha Agrawal, Jayne Matthews, Anne-Maree Haynes, Zhixin Liu, Warrick Delprado, Ron Shnier, Theo M de Reijke, Nathan Lawrentschuk, Pascal E F Stijns, John W Yaxley, Matthijs J Scheltema, Phillip D Stricker

Garvan Institute of Medical Research and The Kinghorn Cancer Centre, Darlinghurst, Sydney, NSW, Australia; Department of Urology, St. Vincent's Prostate Cancer Research Centre, Darlinghurst, Sydney, NSW, Australia; Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers (location VUmc), Free University, Amsterdam, The Netherlands. Electronic address: ., Garvan Institute of Medical Research and The Kinghorn Cancer Centre, Darlinghurst, Sydney, NSW, Australia; Department of Urology, St. Vincent's Prostate Cancer Research Centre, Darlinghurst, Sydney, NSW, Australia., Department of Urology, St. Antonius Hospital, Nieuwegein, The Netherlands., Department of Urology, Amsterdam University Medical Centers (location AMC), University of Amsterdam, Amsterdam, The Netherlands; Prostate Cancer Network The Netherlands, Amsterdam, The Netherlands., Department of Urology, E.J. Whitten Prostate Cancer Research Centre at Epworth, Melbourne, VIC, Australia., Department of Urology, St. Vincent's Prostate Cancer Research Centre, Darlinghurst, Sydney, NSW, Australia., Garvan Institute of Medical Research and The Kinghorn Cancer Centre, Darlinghurst, Sydney, NSW, Australia., Department of Biostatistics, University of New South Wales, NSW, Australia., Douglass Hanly Moir Pathology, Sydney, NSW, Australia., I-MED Radiology, Sydney, NSW, Australia., Department of Urology, Amsterdam University Medical Centers (location AMC), University of Amsterdam, Amsterdam, The Netherlands., Department of Urology, The Wesley Hospital, Brisbane, QLD, Australia., Garvan Institute of Medical Research and The Kinghorn Cancer Centre, Darlinghurst, Sydney, NSW, Australia; Department of Urology, St. Vincent's Prostate Cancer Research Centre, Darlinghurst, Sydney, NSW, Australia; Department of Urology, Amsterdam University Medical Centers (location AMC), University of Amsterdam, Amsterdam, The Netherlands; Prostate Cancer Network The Netherlands, Amsterdam, The Netherlands.