BACKGROUND: : Following failed radiation therapy for prostate cancer there are limited curative options for those patient with a local recurrence. Salvage cryoablation has historically been associated with a high incidence of complications. The objective of this study is to report contemporary outcomes of salvage cryoablation at several institutions, both academic and community, which have participated in the Cryo On-Line Data (COLD) Registry.
METHODS: A secure on-line database was developed consisting of case report forms designed to collect relevant pre and post treatment information for patients undergoing cryoablation following pathologically confirmed failed definitive radiation therapy for localized prostate cancer. Patients were stratified according to their pre cryoablation (post radiation therapy) PSA score (< 10 vs. ≥ 10 ng/ml). Kaplan-Meier (KM) analysis was performed with biochemical failure defined according to the 2006 ASTRO definition of biochemical failure of nadir+2. Incontinence was defined any leak of urine at 12 months as determined by physician interview and was also stratified according to pad use.
RESULTS: Twelve physicians participated and 277 patients were entered. The average age was 70.0 ± 7.1 years. Pre treatment PSA was 7.6 ± 8.2 ng/ml and the median Gleason sum was 7. Of the 277 patients 215 (77.6%) had a PSA < 10 ng/ml. Patients were followed for 21.6 ± 24.9 months with 47 having at least five year follow-up. KM analysis demonstrated five-year actuarial biochemical disease free rates of 61.6 ± 6.3% and 26.6 ± 9.8% for patients with a pre cryoablation PSA < 10.0 and ≥ 10 ng/ml, respectfully (p<0.01). The rectal fistula rate was 1.2%, and incontinence was 6.4% with 3.8% requiring pad use 12 months after therapy.
CONCLUSIONS: Salvage cryoablation offers a potentially curative option following failed radiation therapy and is associated with a morbidity profile favorable in comparison to salvage prostatectomy. Biochemical survival is significantly higher for patients with a pre cryoablation PSA < 10 ng/ml. In contrast to high historical rates, data from patients in the COLD registry indicate that the occurrence of rectal fistulas and incontinence is much less common than in the past. Efforts to continue to minimize these complications should continue.