Focal cryosurgical ablation of the prostate: a single institute's perspective

With the stage migration of prostate cancer witnessed in the late 1990's and early 2000's along with the persistent morbidities associated with prostatectomy and radiation therapy, the concept of focal prostate cancer treatment remains quite attractive. Herein we evaluate the tolerability and non-oncologic outcomes of a highly select cohort of men that underwent focal cryoablation of the prostate for the treatment of localized prostate cancer.

Pre-operatively, erectile function was assessed by SHIM questionnaire while voiding symptoms were assessed by AUA symptom score. Twenty-six highly select patients (23 low-risk prostate cancer and 3 intermediate-risk prostate cancer) with documented minimal disease on saturation prostate biopsy underwent focal cryoablation of the prostate (24 hemi-ablation and 2 subtotal ablation). Subsequently, serum PSAs were obtained every 3 months for 2 years and then every 6 months thereafter. PSA failure was defined as an increase of 0.50 ng/ml over nadir. Mean follow-up was 19.1 months. Subjective assessment of erectile function and voiding was assessed post-operatively at each visit.

Based on our PSA failure definition, 11.5% (3 patients) of the cohort experienced biochemical failure. In two of the three patients, localized disease was detected on subsequent transrectal ultrasound guided biopsy. These two patients went on to have favorable PSA nadirs after undergoing conventional definitive therapy (one patient had external beam radiation and one patient had whole gland cryoablation). Within the study cohort, 27% (7 patients) reported new post-operative erectile dysfunction requiring therapy while no patients reported new post-operative urinary incontinence or worsening of voiding symptoms.

These preliminary results add to the expanding body of literature that the minimally invasive focal cryosurgical ablation of the prostate is a safe procedure with few side effects. The true extent of cancer control remains in question, but in highly select patients, favorable PSA kinetics have been demonstrated. If confirmed by further studies with long-term follow-up, this treatment approach could have a profound effect on prostate cancer management.