Cryotherapy proves effective for small renal cell tumors

Despite physician skepticism, mounting clinical evidence shows that cryoablation eradicates renal cell carcinomas4 cm or smaller with the assurance that they will not reappear for at least a year.

Interventionalist Dr. Christos Georgiades and colleagues at Johns Hopkins University Hospital assessed 35 patients with localized renal cell carcinoma confirmed by biopsy. All patients underwent CT-guided cryoablation and quarterly follow-up for about four years. The investigators found that treatment showed 97% efficacy in tumors 4 cm or smaller and almost 90% efficacy in tumors up to 7 cm at one-year follow-up.

The findings, presented at the 2008 Society of Interventional Radiology meeting, complement other ongoing research.

"We expect that laparoscopic partial nephrectomy and percutaneous cryoablation will be shown to be equivalent in a comparative study that is ongoing now at Johns Hopkins," Georgiades said.

Citing a separate study, he warned about the high likelihood of short- and long-term complications associated with renal cryotherapy. Nearly a fifth of 50 procedures in the analysis resulted in clinically significant morbidities that could beavoided by following proper technique, Georgiades said.

In a third study at Wayne State University Medical Center in Detroit, Dr. Hussein D. Aoun found only six of 90 patients who underwent cryoablation of kidney lesions, including primary renal cell carcinoma, showed local tumor recurrence in the year after treatment. Researchers observed rates of 7% and 3% for minor and major complications, respectively, which they graded using National Cancer Institute criteria.

Despite its long history, cryotherapy remains largely ignored by the mainstream medical community. It is, however, FDA approved, widely available at major institutions, and coveredby health insurance, accoring to Georgiades.