US-guided percutaneous cryoablation of prostate cancer.

A tailored approach to cryosurgery of prostate cancer is presented. The authors have performed 214 cryoprocedures to date with use of this protocol. The technique requires pretreatment with androgen ablation therapy, preoperative diagnosis and staging with ultrasound (US)-guided biopsies, and detailed knowledge of prostate and rectal anatomy. Five cryoprobes are placed in the prostate under US guidance in a configuration that depends on tumor location, sites of extracapsular extension, the size of the tumor, and gland geometry. Freezing starts anteriorly to keep from obstructing the ultrasound beam. Two freezes are performed at the known cancer site, and additional freezes are performed, if necessary, to include the remainder of the gland. Thermosensors enable monitoring of the cryosurgical ice ball and determination of the number of freezes. Cryosurgery is always performed by a urologist and a radiologist working together.