Prostate Cancer Cryoablation

Background and indications

Prostate cancer is the most common cancer in men. When localized and low-to-intermediate risk (Gleason score ≤ 7, PSA < 20 ng/mL, stage ≤ T2b), focal cryoablation may be offered as an alternative to radical prostatectomy or radiation therapy. The goal is to specifically destroy the tumor zone identified on MRI while preserving surrounding healthy prostate tissue, urinary continence, and erectile function.

Focal cryoablation is also offered as salvage therapy after radiation failure, a situation where surgery is technically difficult and associated with significant complications.

Pre-procedure assessment

Assessment includes multiparametric prostate MRI identifying the tumor focus(es) (PI-RADS score), targeted MRI-ultrasound fusion biopsies confirming histological grade, PSA measurement, and staging workup if needed (CT scan, bone scintigraphy, or PSMA-PET). The case is discussed at a multidisciplinary tumor board meeting.

Procedure

Under general or spinal anesthesia, cryoprobes (17G needles) are inserted transperineally under transrectal ultrasound and/or MRI fusion guidance. The cryoprobes deliver gas (argon) that cools tumor tissue to -40°C, causing cellular destruction through intracellular crystallization and vascular ischemia. Two freeze-thaw cycles are performed. Temperature sensors are placed near the urethral sphincter and rectum to protect these structures. A urethral warmer is used during the procedure. The procedure takes approximately 1 to 2 hours.

Results and scientific evidence

A retrospective study of 163 patients with a median follow-up of 39 months showed an 85% biochemical recurrence-free survival rate (Phoenix criteria) at 3 years for focal prostate cryoablation (Khan et al., Cureus, 2023; DOI: 10.7759/cureus.37172).

Urinary continence preservation rates exceed 95% and erectile function preservation rates are 70-85% with focal treatment, significantly better than after radical prostatectomy. Control biopsies at 12 months show absence of residual cancer in the treated zone in 80-90% of cases.

Risks and complications

Major complications are rare: transient urinary retention (5-10%, requiring temporary catheterization), urinary tract infection (< 5%), mild hematuria (< 5%). Severe incontinence (< 1%) and recto-urethral fistula (< 0.5%) are exceptional with focal treatment. Erectile dysfunction is less frequent than after radical surgery but possible when treatment is near the neurovascular bundles.

Recovery

A urinary catheter is left in place for 5 to 7 days. Return to normal activities is possible after 1 to 2 weeks. Close follow-up is required with PSA measurement every 3 months in the first year, then every 6 months, and control MRI at 6 and 12 months. Control biopsies are recommended at 12 months.

Practical information

The procedure is performed as an outpatient or short inpatient stay depending on the case. It is performed by an interventional radiologist specialized in oncology, in coordination with the urologist and radiation oncologist.