NanoKnife, a medical device for prostate cancer, destroys a targeted tumor with electrical pulses. For men with one clearly visible, moderately aggressive tumor, the treated area is usually cleared, bladder control is almost always kept, and most men keep their erections. A meaningful share later have cancer found elsewhere in the prostate; scans miss much leftover cancer, so repeat biopsies are needed. Professional bodies call it unproven against standard treatment. (Full Review)

Protocol

Standard procedure

2–6 needle electrodes, about 90 pulses

Under general anesthesia; placed through the perineum with ultrasound guidance and MRI fusion; pulses synchronized to the heartbeat (ECG)

Ablation extent

Focal, hemi-gland or extended

One expert review reports better cancer control with hemi-gland and better erectile preservation with focal ablation

Procedure and recovery

1–2 hours; single session

Often a day case or overnight stay; catheter 3–7 days; most men resume normal activity within 1–2 weeks

Time to effect

Tissue death

Immediate

The ablation is permanent; no drug remains in the body

Biopsy confirmation

12 months

Biopsy confirms whether the tumor was destroyed

PSA lowest point

Median 3.5 months

Tracked against own baseline; no validated failure threshold

Benefits

High: Ablation of the targeted tumor; urinary continence and urinary symptoms preserved; erectile function largely preserved

Medium: Avoidance of radical treatment for years

Low: Later surgery remains feasible

Speculative: Systemic anti-tumor immune activation

Contraindications

Metastatic disease (lymph node or distant spread)

High-risk cancer outside a clinical trial (grade group 4–5, PSA above 20 ng/mL or stage T3 or higher)

Multifocal clinically significant cancer in both lobes that no focal or hemi-gland template can cover

Low-volume grade group 1 cancer

Unfit for general anesthesia (American Society of Anesthesiologists physical status IV or higher)

Active untreated urinary tract infection or uncorrectable bleeding disorders (INR above 1.5 or platelets below 50 × 10⁹/L)

Unstable cardiac arrhythmia or heart attack within the past 3 months

Life expectancy under 10 years

Key Interactions

Anticoagulants (warfarin, apixaban, rivaroxaban, dabigatran): caution, bleeding and hematuria

Antiplatelet drugs (clopidogrel, ticagrelor, prasugrel): caution, increased bleeding

NSAIDs (aspirin, ibuprofen, naproxen): caution, increased bleeding

Supplements with antiplatelet effects (fish oil, vitamin E, Ginkgo biloba, garlic, turmeric): caution, additive bleeding risk

Implanted cardiac devices (pacemakers, implantable defibrillators): caution, device interference and arrhythmia

Testosterone therapy (testosterone cypionate, gels): caution, may stimulate residual cancer

Prior pelvic radiotherapy: caution, greater tissue injury, sloughing and fistula risk

Neuromuscular blocking agents (rocuronium, vecuronium): required

5-alpha-reductase inhibitors (finasteride, dutasteride): monitor, roughly halve PSA

Androgen deprivation therapy (leuprolide, degarelix, relugolix): monitor, confounds assessment of ablation success

Alpha-blockers (tamsulosin, alfuzosin): monitor, dizziness on standing

PDE5 inhibitors (sildenafil, tadalafil): monitor (beneficial); absolute contraindication with nitrates (nitroglycerin, isosorbide mononitrate)

Saw palmetto (Serenoa repens): monitor, may slightly alter urinary symptoms and PSA readings

Risk & Side Effects

High: Cancer persisting or arising elsewhere in the gland; decline in erectile function; short-term urinary symptoms, hematuria and hematospermia; urinary tract infection and epididymitis; urinary incontinence

Medium: Urethral sloughing and stricture; residual cancer missed on follow-up MRI; rectourethral fistula

Low: Cardiac arrhythmia

Speculative: Tumor seeding along needle tracks

Monitoring

Marker	Target	Why
PSA (total)	Before: under 10 ng/mL. After: no established target; track nadir and trend against own baseline (60–70% fall by 6–12 months typical)	Response and relapse
PSA density	Under 0.15 ng/mL/cm³	Flags hidden cancer
Prostate MRI score	Before: single PI-RADS 4–5 lesion of 20 mm or less. After: PI-FAB 1 (no suspicious enhancement)	Target and residual disease
Biopsy grade group	Before: grade group 2–3 in the index lesion only. After 12 months: no grade group 2 or higher	Confirms ablation
PSMA PET/CT	No uptake outside the prostate; single intraprostatic focus	Excludes spread and extra lesions
IIEF-5 score	22–25	Sexual function
IPSS	0–7	Urinary symptoms
EPIC-26 incontinence domain	Pad-free; score near 100	Continence
Urine culture	No growth	Infection before ablation
Platelets and INR	Platelets 150–400 × 10⁹/L; INR 1.0–1.1 off anticoagulants	Bleeding risk
eGFR	90 mL/min/1.73 m² or higher	Contrast MRI and anesthesia safety
ECG	Normal sinus rhythm	Pulse synchronization and anesthesia

Cadence: PSA at 3, 6, 9 and 12 months, then every 6 months to year 5 and annually thereafter; MRI at 6–12 months, then every 1–2 years or when PSA rises; biopsy of the treated zone and remaining gland at 12 months regardless of MRI findings; questionnaires at 3, 6 and 12 months, then yearly

Qualitative Assessment

Urinary stream strength, urgency and any leakage during daily activities
Quality of erections, including morning erections, and ejaculatory volume
Return of energy and normal physical activity after recovery
Level of anxiety about recurrence and around PSA or biopsy results
Overall satisfaction with the treatment decision

NanoKnife to Treat Prostate Cancer

Protocol

Benefits

Risk & Side Effects

Monitoring

Qualitative Assessment