van den Bos W, et al. – In this study, the safety, quality of life (QoL) and short–term oncological outcomes of primary focal IRE for the treatment of localized prostate cancer were determined. They further distinguish potential risk factors for oncological failure. The results demonstrates the safety and feasibility of focal IRE as a primary treatment for localized prostate cancer (PCa) with effective short–term oncological control in carefully selected men.

Methods

• For this analysis, patients that met both the consensus guidelines on patient criteria and selection methods for primary focal therapy were eligible.
• They conducted focal IRE for organ–confined clinically significant PCa, being high–volume Gleason sum score 6 (ISUP grade 1) or any Gleason sum score 7 (ISUP grade 2–3).
• They examined oncologic, adverse event and QoL outcome data with a minimum of 6 months follow–up.
• They compared patient characteristics and peri–operative treatment parameters for patients with and without oncological failure on follow–up biopsy.
• They applied Wilcoxon's Signed Rank Test, Wilcoxon's Rank Sum Test and Chi–square test to evaluate statistically significant differences in paired continuous, unpaired continuous and categorical variables respectively.

Results

• They enrolled a sum of 63 patients for final analysis.
• There were no high–grade adverse events.
• According to the data, quality of life questionnaire analysis indicated no significant change in physical (p=0.81), mental (p=0.48), bowel (p=0.25) and both urinary QoL domains (p=0.41 and p=0.25); there was a mild decrease in the sexual QoL domain (median score 66 at baseline vs 54 at 6 months, p=0.0003).
• A decline of 70% (1.8, IQR 0.96–4.8) was seen between 6–12 months when compared to baseline PSA.
• They distinguished a narrow safety margin (p=0.047) and system errors (p=0.010) as potential early risk factors for in–field oncological failure.
• In–field and whole–gland oncological control on follow–up biopsies was 84% (38/45) and 76% (34/45); this increased to 97% (38/39) and 87% (34/39) when patients treated with a narrow safety margin and system errors were excluded.