Karen Elaine Reisiger MD, Presenter: Nothing to Disclose

Lance A. Mynderse MD, Abstract Co-Author: Nothing to Disclose

David Arthur Woodrum MD, PhD, Abstract Co-Author: Nothing to Disclose

To establish the feasibility of MR guided cryoablation in patients with biopsy proven local recurrence of prostate adenocarcinoma.

Under IRB approval, we reviewed the outcome of 12 men ages 52-78 treated with MR guided cryoablation (Galil Medical, Minneapolis, MN) of biopsy proven prostate adenocarcinoma local recurrence following radical prostatectomy. The initial recurrence was treated with external beam radiation (5), hormone ablation (7), and/or laser ablation (2). Surgical pathology was extremely unfavorable; 10/12 patients had a Gleason 7-9 lesion, 3/12 positive surgical margins, 1/12 extraprostatic extension, 2/12 perineural invasion and 1/12 with positive lymph node(1). Patients had no known distant metastases. Under general anesthesia, the patients were brought into a wide-bore 1.5T MRI (Siemens Medical, Malvern, PA) suite, in supine feet first position with an endorectal coil in place. A needle guide grid was placed against the perineum, and was co-localized with the prostate imaging data set. 2-5 cryotherapy probes were placed in/around the recurrence with intermittent MRI guidance. In some cases, saline displacement of the rectum was employed. A MRI compatible urethral warming catheter (Galil Medical, Minneapolis, MN) was used to prevent urethral thermal damage. 2-3 cycles of freezing were performed with sequential intra-procedural MR imaging to monitor iceball growth. Treatment duration was determined by iceball coverage of the lesion 5mm beyond its margin. Active thawing was performed after each freeze cycle.

After overnight observation, and each was followed with PSA at 4 weeks, and contrast enhanced MR at 3 months. There were no immediate complications, with no urethral or rectal injuries. One patient experienced urinary retention which resolved after two weeks of indwelling Foley catheter. Early results are mixed and include recurrence adjacent to the urethra in 2 patients. We postulate that the urethral warmer prevents adequate freezing in this region.

MR guided cryoablation of prostate cancer recurrence is safe and feasible. Further work is necessary to define the treatment durability and proper patient selection.

Local recurrence of prostate adenocarcinoma following radical prostatectomy, radiation therapy and hormone ablation often proves a clinical dilemma with few options left for the patient.

Reisiger, K, Mynderse, L, Woodrum, D, MR-guided Cryoablation of Prostate Adenocarcinoma Recurrence: The Mayo Clinic Experience.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11006486.html