Researchers involved in the Cryo On-Line Data (COLD) Registry have reported the results of salvage cryoablation for patients with localized prostate cancer that is recurrent after radiation therapy. The details of this study were reported at the 2007 meeting of the American Urological Association (AUA) in May.[1]

Cryosurgery was first used to treat prostate cancer in the early 1970s, but it was not until 1993, when the results from percutaneous ultrasound-guided cryosurgery were published, that the potential advantages of this treatment became apparent. Changes in equipment and techniques have improved the results of cryosurgery, in both tumor control and lower morbidity. Ultrasound-guided percutaneous transperineal placement of the cryoprobes allows monitoring of freezing in real time. Monitoring temperature at critical locations, separating the rectum and prostate by saline injection, and using argon gas rather than liquid nitrogen-based equipment have improved results and lowered complication rates. The technique is reported to produce outcomes similar to those obtained with brachytherapy and three-dimensional conformal radiation. Advantages of cryosurgery include the ability to re-treat patients without added morbidity and to treat salvage post-radiation patients with acceptable results and morbidity. There is also the possibility that "nerve-sparing" cryosurgery is possible. A randomized study presented at the 2007 AUA meeting demonstrated that cryoablation was at least equivalent to radiation therapy for the primary treatment of localized prostate cancer.[2]

The COLD study involved 277 patients with recurrent prostate cancer following radiation therapy treated with cryoablation by 12 different physicians. The average age of this population was 70 years. The average pretreatment PSA was 7.6 and the median Gleason sum was 7. The median follow-up was 22 months with 47 patients being followed for at least 5 years. The 5 year biochemical disease-free survival was 55%. The positive biopsy rate was 6%. Complications included rectal fistula in 1.2%, incontinence in 6.4% with 3.8% requiring pad use. These authors suggest that cryoablation offered a curative option after failure of radiation therapy. These authors also suggested that there were significant improvements in cryoablation over time with currently less complications.

Comments:It would appear that the results of cryoablation have improved to the point of where it is appropriate to ask the question of whether cryoablation should be the first choice of therapy and radiation therapy reserved for salvage therapy.

References:

Cryosurgery May Be Effective for High-Risk Early Prostate Cancer (04/13/2005)