JU INSIGHT: Focal Therapy of Prostate Cancer Index Lesion With Irreversible Electroporation: A Prospective Phase II Study With a Median Follow-up of 3 Years

By: Bernardino Miñana López, MD, PhD; Guillermo Andrés Boville, MD, PhD; Guillermo Barbas Bernardos, MD, PhD; Xabier Ancizu Marckert, MD; Marcos Torres Roca, MD; Luis Labairu Huerta, MD, PhD; Felipe Villacampa Aubá, MD; Fernando Ramón de Fata Chillón, MD, PhD; Julian Sanz Ortega, MD, PhD; Marta Abengózar Muela, MD; Guillermo Gallardo Madueño, MD; Alberto Benito Boíllos, MD, PhD; Andrés Alcázar Peral, MD; Fernando Díez-Caballero Alonso, MD, PhD | Posted on: 17 Jan 2023

Miñana López B, Andrés Boville G, Barbas Bernardos G, et al. Focal therapy of prostate cancer index lesion with irreversible electroporation: a prospective phase II study with a median follow-up of 3 years. J Urol. 2023;209(1): 261-270.

Study Need and Importance

Focal therapy (FT) for prostate cancer (Pca) is a therapeutic approach aiming for tumor control while minimizing the side effects that can be associated with radical treatments. Irreversible electroporation (IRE) is a nonthermal tissue ablation technology based on the emission of short electrical pulses that allows treatment on any part of the prostate with a security margin.

The widespread use of multiparametric MRI (mpMRI) and the development of ultrasound-MRI fusion systems for targeting biopsies allow the implementation of FT programs. However, long-term results on its ability to achieve cancer control and preserve functional outcomes, especially using IRE, are still lacking.

Table. Unfavorable Urodynamic Parameters

Parameter	Within the first year of SCI	1-Mo follow-up	3-Mo follow-up	6-Mo follow-up	12-Mo follow-up
Urodynamics performed, No. (%)	97 (100)	90 (93)	85 (88)	75 (77)	73 (75)
DO and DSD, No. (%)	85 (88)	61 (68)	63 (74)	55 (73)	52 (71)
Maximum storage detrusor pressure
≥40 cm H₂O, No. (%)	38 (39)	21 (23)	18 (21)	24 (32)	11 (15)
Filling volume when pDet = 40 mL, median (Q1-Q3)	–	505 (215-610)	525 (278-753)	398 (258-663)	300 (195-500)
Bladder compliance <20 mL/cm H₂O, No. (%)	0 (0)	0 (0)	0 (0)	0 (0)	0 (0)
Videourodynamics performed, No. (%)	96 (99)	88 (98)	76 (89)	67 (89)	68 (93)
Vesicoureteral reflux, No. (%)^a	7 (7)	4 (5)	5 (7)	2 (3)	2 (3)
At least 1 unfavorable parameter, No. (%)	87 (90)	65 (72)	67 (79)	61 (81)	55 (75)
Abbreviations: DO, detrusor overactivity; DSD, detrusor sphincter dyssynergia; pDET, detrusor pressure; Q, quartile; SCI, spinal cord injury. ^aVesicoureteral reflux grade: 1 month, 4 grade I; 3 months, 1 grade I, 3 grade II, 1 grade III; 6 months, 1 grade II, 1 grade III; 12 months: 2 grade I.

To our knowledge this is the first prospective study published with all patients selected based on a combination of mpMRI and a transperineal systematic and targeted systematic transperineal biopsy using an MRI-ultrasound fusion system (Koelis System) without loss of patients to follow-up.

Patients were selected if they had a biopsy-proven low- to intermediate-risk Pca concordant with lesions visible on mpMRI. All procedures were performed by the same surgeon.

Figure. Kaplan-Meier curves showing in-field and out-of-field recurrence-free survival.

What We Found

FT using IRE is a reliable, safe, and effective procedure for treating Pca with 85% probability of achieving tumor control in the treated volume at 3 years. There seems to be a risk of recurrence over time in untreated areas (see Figure).

Continence was preserved in all patients and potency in 94% of those previously potent.

Limitations

Limitations included: single center; small sample (41 patients); 80% underwent control biopsy and most patients had low risk-Pca (International Society of Urological Pathology grade 1-2).

Interpretation for Patient Care

FT using IRE is a minimally invasive therapeutic option for patients with visible lesions on mpMRI with minimal side effects. At least, it could delay radical treatments in patients on active surveillance. A close follow-up is needed.