Focal therapy for prostate cancer with irreversible electroporation: Oncological and functional results of a single institution study

Abstract

Purpose: Focal irreversible electroporation (IRE) for prostate cancer aims to reduce quality of life complications, however outcomes data remains limited. We aimed to evaluate histological in-field clearance of prostate cancer at ≥12 months post-IRE. Materials and Methods: Retrospective review of prospectively acquired data of consecutive patients treated between August 2018 and August 2021. Significant recurrence was defined as a ≥6 mm core Gleason 3+3, or ≥Gleason 3+4 with ≥4 mm tumour length. A second definition of any focus of International Society of Urological Pathology (ISUP) ≥2 was also analysed. Results: The median follow-up of the entire cohort is 23 months (range 3–39 mo). For 64 primary IRE procedures, surveillance biopsy was performed in 40/50 (80.0%) with ≥12 months follow-up. Significant in-field recurrence occurred in 3/40 (7.5%), or 4/40 (10.0%) with any focus of ISUP >2. Significant out-of-field recurrence occurred in 5/40 (12.5%). In salvage IRE, three patients (3/6, 50.0%) have undetectable prostate-specific antigen levels, two have no residual cancer on biopsy and one patient had out-of-field recurrence. For sexually active men, erectile function was maintained in 24/28 (85.7%) of primary IRE. No incontinence developed in primary IRE (0/64). Conclusions: Focal primary IRE for prostate cancer is associated with 90% infield ablation of any ISUP grade >2 cancer with a low risk of urinary incontinence or impotence. Surveillance prostate biopsies are required to exclude progression despite a normal post-IRE multiparametric magnetic resonance imaging (mpMRI). Salvage IRE is a promising option for localised recurrence after prostate radiotherapy with low morbidity.

Keywords

• focal therapy
• irreversible electroporation
• prostate cancer
• surveillance biopsy
• urinary incontinence