Irreversible electroporation (IRE) is a novel ablation modality using electric pulses to create nanoscale defects in the cell membrane. It has been verified to be safe on the treatment of prostate, lung, liver and kidney masses. The present is a randomized, controlled trial, with a main purpose of looking into the safety and feasibility of irreversible electroporation for patients with benign prostatic obstruction.

Benign prostatic obstruction (BPO) is the main reason to cause lower urinary tract symptoms (LUTS) in aged male. Oral medications, such as,α1-adrenoceptor antagonist and 5α-reductase inhibitors are the mainstay treatment options. However, some patients can not tolerate long-term use, due to either side effects or limited efficacy. Though transurethral resection or enucleation of prostate usually achieve significant symptom improvement, it's an end stage procedure and it is only reserved for carefully selected patients.

The development of focal ablative therapy yields minimally invasive treatment option for primary tumors such as the liver, lung, pancreas, kidney, and prostate. Among the novel techniques are cryoablation, radiofrequency ablation (RFA), microwave ablation, and high-intensity focused ultrasonography. Irreversible electroporation (IRE) is a one of the ablation modalities using electric pulses to create nanoscale defects in the cell membrane. IRE is not dependent on thermal energy and is therefore causing minimum damage to the blood vessels, nerves and tissue architecture. The present is a randomized, controlled trial, with a main purpose of looking into the safety and feasibility of irreversible electroporation for patients with benign prostatic obstruction.

Inclusion Criteria:

1. Male, 45 years or older.
2. The presence of voiding symptoms, i.e. slow stream, intermittent stream, hesitancy, straining, etc.
3. Qmax ≥ 5 mL/s and ≤ 15 mL/s with minimum voided volume of 125 mL or more during flow study.
4. The presence of bladder outlet obstruction during pressure-flow study.
5. International Prostatic Symptom Score (IPSS) ≥ 12 at screening.
6. Prostate volume ≥ 30 ml (using a transrectal ultrasound approach).
7. Total serum prostatic specific antigen (PSA) ≥ 1.5 ng/mL and ≤ 10 ng/mL at screening.
8. Subject is able to communicate and complete the questionnaires properly.
9. Written informed consent.

Exclusion Criteria:

1. Diagnosis or suspicion of bladder, prostate, urethral or pelvic tumor.
2. Patients with arrhythmia or history of cardiac pacemaker implantation.
3. Known lower urinary tract or pelvic surgical history.
4. Voiding symptoms as a result of urethral stricture, stone diseases, chronic prostatitis, space-occupying lesions etc.
5. Known neurogenic or congenital lower urinary tract dysfunction.
6. Rigid or flexible cystoscopy examination within the past 7 days at screening.
7. Existence of anatomical abnormalities of the urinary tract (e.g. diverticulum of the bladder or urethra, ectopic ureteral orifice etc.).
8. The presence of acute conditions, such as, urinary tract infection, fever, heart failure etc.
9. Patients with poor compliance or cognitive competence.

The data will be analyzed in a blinded manner.