Focal Cryotherapy for Clinically Unilateral, Low-Intermediate Risk Prostate Cancer in 73 Men with a Median Follow-Up of 3.7 Years

Abstract

BackgroundEvolution of cryotherapy for prostate cancer is likely to result in parenchyma-sparing modifications adjacent to the urethra and neurovascular bundle. Results of initial series of focal therapy to minimize cryosurgery-related morbidity without compromising oncologic control have been encouraging, but limited in short-term outcomes. ObjectiveTo retrospectively report (1) median 3.7-yr follow-up experience of primary focal cryotherapy for clinically unilateral prostate cancer with oncologic and functional outcomes, and (2) matched-pair analysis with contemporaneous patients undergoing radical prostatectomy (RP). Design, setting, and participantsOver 8.5 yr (September 2002 to March 2011), focal cryoablation (defined as ablation of one lobe) was performed in 73 carefully selected patients with biopsy-proven, clinically unilateral, low-intermediate risk prostate cancer. All patients underwent transrectal ultrasound (TRUS) and Doppler-guided sextant and targeted biopsies at entry. Outcome measurements and statistical analysisPost-therapy follow-up included measuring prostate-specific antigen (PSA) level every 3–6 mo; TRUS biopsies at 6–12 mo and yearly, as indicated; and validated symptom questionnaires. Matched-pair analysis compared oncologic outcomes of focal cryotherapy and RP (matched for age, PSA, clinical stage, and biopsy Gleason score). Results and limitationsComplete follow-up was available in 70 patients (median follow-up: 3.7 yr; range: 1–8.5 yr). No patient died or developed metastases. Precryotherapy mean PSA was 5.9 ng/ml and Gleason score was 6 (n=30) or 7 (n=43). Postcryotherapy mean PSA was 1.6 ng/ml (70% reduction compared to precryotherapy; p<0.001). Of 48 patients undergoing postcryotherapy biopsy, 36 (75%) had negative biopsies; positive biopsy for cancer (n=12) occurred in the untreated contralateral (n=11) or treated ipsilateral lobe (n=1). Complete continence (no pads) and potency sufficient for intercourse were documented in 100% and 86% of patients, respectively. Matched-pair comparison of focal cryotherapy and RP revealed similar oncologic outcome, defined as needing salvage treatment. ConclusionsPrimary focal cryoablation for low-intermediate risk unilateral cancer affords encouraging oncologic and functional outcomes over a median 3.7-yr follow-up. Close surveillance with follow-up whole-gland biopsies is mandatory.