Median 4-year outcomes of salvage irreversible electroporation for localized radio-recurrent prostate cancer.

Abstract

To evaluate the safety, and short to mid-term oncological and quality-of-life (QoL) outcomes of focal irreversible electroporation (IRE) for radio-recurrent prostate cancer (PCa) at a median follow-up of 4 years. This was a single-centre series of men with biopsy-proven radio-recurrent PCa treated with IRE between December 2013 and February 2022, with a minimum follow-up of 6 months. Follow-up included magnetic resonance imaging at 6 months, and standard transperineal saturation template biopsies at 12 months. Further biopsies were guided by suspicion on serial imaging or prostate-specific antigen (PSA) levels. Validated questionnaires were used to measure functional outcomes. Significant local recurrence was defined as any International Society of Urological Pathology (ISUP) score ≥ 2 on biopsies. Progression-free survival was defined as no signs of local or systemic disease on either imaging or template biopsies, or according to the Phoenix criteria for biochemical recurrence. Final analysis was performed on 74 men with radio-recurrent PCa (median age 69 years, median PSA level 5.4 ng/mL, 76% ISUP score 2/3). The median (range) follow-up was 48 (27-68) months. One rectal fistula occurred, and eight patients developed urethral sloughing that resolved with transurethral resection. Among patients who returned questionnaires (30/74, 41%), 93% (28/30) had preserved urinary continence and 23% (7/30) had sustained erectile function at 12-month follow-up. Local control was achieved in 57 patients (77%), who needed no further treatment. Biopsy diagnosed 41(55%) patients received follow up template biopsies, in-field recurrences occurred in 7% (3/41), and out-field recurrences occurred in 15% of patients (6/41). The metastasis-free survival rate was 91% (67/74), with a median (interquartile range) time to metastases of 8 (5-27) months. The Kaplan-Meier estimated 5-year progression-free survival rate was 60%. These short- to mid-term safety, oncological and QoL outcome data endorse results from smaller series and show the ability of salvage focal IRE to safely achieve oncological control in patients with radio-recurrent PCa.