Studies Demonstrate Effectiveness of Cryoablation for Kidney Cancer

Endocare, Inc, a medical device company focused on the development of minimally invasive technologies for tissue and tumor ablation, announced that six studies and papers demonstrating the effectiveness of cryoablation for treating renal cancer were published in a supplement to the July 2006 issue of Urology. The studies also help show that renal cryoablation, which involves freezing and destroying the diseased tissue using an Endocare cryoablation device, is a less invasive treatment option than the standard surgical procedure, which involves full or partial removal of the affected kidney, and generally results in less morbidity, faster recovery, and fewer complications.

Beyond Prostate Cancer

Taken as a whole, the six published papers, which include 379 patients and comparisons between cryoablation and other ablative treatments, show that cryoablation can be a safe and effective treatment for renal cancer with few serious complications and can be repeated if the disease reoccurs. The physicians participating in the papers come from leading medical institutions including the Cleveland Clinic, Johns Hopkins, UCI Medical Center, and Hahnemann University Hospital, among others.

"It has already been well documented that cryoablation is an effective treatment for prostate cancer, but these studies and papers show that a growing number of physicians from some of the leading medical institutions are using our tumor-freezing technology for the ablation of renal cancers as well," said Craig T. Davenport, Chairman and Chief Executive Officer of Endocare. "This is further evidence that the advances we have made in targeting the tumors throughout the body and accurately destroying the diseased tissue without damaging surrounding healthy tissue are providing better outcomes for patients battling the often deadly effects of cancer."

Six Studies

The six studies are summarized as follows:

• Long-Term Results of Cryoablation for Renal Cancer and Complex Renal Masses. The first ever 5-year study of 48 patients (with a median follow-up of 64 months) showed a cancer-specific survival rate of 100% and no major complications. Persistent disease was noted in six of the patients (12.5%). After a repeat procedure, five of the six now show no evidence of disease, yielding a 97.5% cancer-free survival rate for all patients in the study.

• Probe-Ablative Nephron-Sparing Surgery: Cryoablation vs Radiofrequency Ablation. A 246-patient study comparing the outcomes of laparoscopic cryoablation and percutaneous radiofrequency ablation of patients at the Cleveland Clinic showed no difference in terms of morbidities, which were minimal for both procedures, or impact on renal function. The most significant finding was the recurrence rate for cryoablation, which was only 1.8% compared to 11.1% for radiofrequency ablation.

• Cryoablation of Small Peripheral Renal Masses: A Retrospective Analysis. In a study of 85 patients with a mean follow-up of 15 months, enhancement was seen for 2.4% of the patients and biopsy-confirmed recurrence was observed in 1.2%. Short-term results are indicative of long-term efficacy, as it has been documented that the median time to failure is only 12 months.

• Percutaneous Renal Cryoablation. This article reviews the evolution of cryoablation and offers promising results for percutaneous cryoablation in terms of both efficacy and morbidity. The cost-effectiveness of the procedure was also cited and longer-term outcomes noted as key to defining the role of computed tomography-guided percutaneous renal cryoablation.

• Review of Minimally Invasive Renal Therapies: Needle-Based and Extracorporeal. In a review of the different approaches to renal ablation, the paper shows that cryoablation and radiofrequency offer the most potential.

• Cryotherapy: Clinical End Points and Their Experimental Foundations. In a review of the cryobiologic foundation upon which renal cryoablation is built and the interactions of ice and tissue, this paper notes that cryoablation has minimal impact on renal function and does not damage the collecting system.