Inclusion Criteria:  Is greater than 50 years of age Has at least a 10-year life expectancy Has histologically confirmed organ-confined prostate cancer, clinical stage ≤ T2c Has a PSA ≤ 15 ng/mL or PSA density < 0.2 ng/mL2 if PSA is > 15 ng/mL Has Gleason score 3+4 or 4+3 Has no evidence of extraprostatic extension by mpMRI Has no evidence of seminal vesicle invasion by mpMRI, and if suspected, confirmed by biopsy Physician is able to visualize prostate gland adequately on transrectal ultrasound imaging during enrollment evaluation Transperineal or transrectal targeted prostate biopsies of lesion, plus 10 core systematic biopsies to include adequate sampling of the peripheral zone correlating with an intermediate risk lesion in the area of the MR-visible lesion A visible lesion on mpMRI that is accessible to Irreversible Electroporation (IRE) treatment (Note: A non-MRI visible lesion detected via systematic standard biopsy will not be considered an exclusion criterion provided the non-MRI visible lesion is singularly located in the contralateral hemisphere of the prostate; is Gleason 6; and comprises no more than 6 mm linear extent of prostate-bearing tissue in a single core on standard biopsy) Has signed a written informed consent and in the judgment of the physician, the study is in the best interest of the subject Understands and accepts the obligation and is logistically able to present for all scheduled follow-up visits  Exclusion Criteria:  Has known hypersensitivity to pancuronium bromide, atricurium or cisatricurium Is unfit for anesthesia or has a contraindication for agents listed for paralysis Has an active urinary tract infection (UTI) Has a history of bladder neck contracture Is interested in future fertility Has a history (within 3 years) of inflammatory bowel disease Has a concurrent major debilitating illness Had active treatment for a malignancy within 3 years, including malignant melanoma, except for prostate cancer or other types of skin cancer Has any active implanted electronic device (e.g., pacemaker) Is unable to catheterize due to a urethral stricture disease  Has had prior or current prostate cancer therapies:  Biologic therapy for prostate cancer Chemotherapy for prostate cancer Hormonal therapy for prostate cancer within three months of procedure Radiotherapy for prostate cancer Surgery for prostate cancer Has had prior transurethral prostatectomy (TURP), stricture surgery, urethral stent or prostatic implants Has had prior major rectal surgery (except hemorrhoids) Is unfit for pelvic MRI scanning (e.g., severe claustrophobia, permanent cardiac pacemaker, metallic implants that are likely to contribute significant image artifacts, allergy or contraindication to gadolinium (to enhance MRI)) Is actively bleeding, is anticoagulated or on blood thinning medications, or has a bleeding disorder Is a member of a vulnerable population such as prisoners, handicapped or mentally disabled persons, or economically or educationally disadvantaged persons In the opinion of the treating physician, has a contraindication listed in the current NanoKnife System User Manual (section 2.3)