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.

Median 5‐year outcomes of primary focal irreversible electroporation for localised prostate cancer

“…However, the slightly higher progression rate in our present study might be explained by the higher standardised biopsy rate (83% vs 36%), lower threshold for progression to salvage treatment and consequently lower metastatic disease burden (0.4% vs 1.6%). Recently, Yaxley et al [12] published their initial experience on 64 IRE patients, externally validating the results of our series by obtaining comparable results. Table 2 Multivariable Cox proportional hazard analysis on the risk to develop a failure during follow-up (progression to radical treatment and/or systemic disease).…”

“…Recently, Yaxley et al. [12] published their initial experience on 64 IRE patients, externally validating the results of our series by obtaining comparable results.…”

Salvage irreversible electroporation for radio‐recurrent prostate cancer – the prospective FIRE trial

“…Of these patients one had a salvage robot-assisted radical prostatectomy, two commenced androgen deprivation therapy (ADT) and one remained on surveillance. The median (IQR) time to salvage therapy was 15 (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22) months). The remaining six patients (16%) developed metastatic disease, of which four had residual local disease while two did not.…”

Guidelines of guidelines: focal therapy for prostate cancer, is it time for consensus?

“…Conversely, results from a smaller series reported by Yaxley et al. [ 25 ] found that risk of in‐field recurrence on biopsy for men with high‐grade PCa after focal IRE was low (none of seven patients).…”

“…A high-risk cohort from a focal HIFU series by Reddy et al [24] found that of 386 patients, 65% had failure-free survival at 7 years and 73% had no salvage (local or systemic) treatment at 7 years. Conversely, results from a smaller series reported by Yaxley et al [25] found that risk of in-field recurrence on biopsy for men with high-grade PCa after focal IRE was low (none of seven patients).…”