SIR: Percutaneous Cryoablation Freezes Out Kidney Tumors

March 5, 2007

SEATTLE -- For eliminating small kidney tumors, percutaneous cryoablation appears to be as effective as laparoscopic cryoablation, and about 60% cheaper, researchers reported here.

SEATTLE, March 5 -- For eliminating small kidney tumors, percutaneous cryoablation appears to be as effective as laparoscopic cryoablation, and about 60% cheaper, researchers said here.

So reported J. Louis Hinshaw, M.D., of the University of Wisconsin in Madison, and colleagues, in a small, retrospective study at the Society of Interventional Radiology meeting.

Because previous studies have shown that removing renal tumors is often curative without taking the entire kidney, treatment has progressively been shifting to less invasive procedures for selected patients, Dr. Hinshaw said.

Their study is the first to directly compare two methods of cryoablation -- laparoscopic and percutaneous -- he added. Cryoablation is approved by the Food and Drug Administration for the treatment of soft tissue tumors, which includes renal cell carcinoma.

It included 19 percutaneous procedures by CT and ultrasound guidance (18 patients, mean age 68.6, 7.3 months mean follow-up) and 48 laparoscopic cryoablations (46 patients, mean age 68.2, 13.3 months mean follow-up) completed at their institution.

Both groups were similar, though tumors treated percutaneously were slightly smaller than those treated laparoscopically (mean 2.0 versus 2.6 cm, P=0.0057). Protocol deemed that tumors in an anterior position or near the bowel or ureter were done laparoscopically because vulnerable structures can be moved out of the way more easily. Those in a posterior or "easier" position were preferentially done percutaneously.

Comparing percutaneous and laparoscopic procedures, the respective findings were:

  • Equivalent efficacy with respect to tumor recurrence (10.5% versus 12.5%, P>0.05),
  • Fewer major complications (0% versus 6.3%, P=0.55),
  • Shorter hospital stay (1.1 versus 2.3 days, P=0.01), and
  • Lower hospital costs (59.5% difference, ,153.69 versus ,556.93, P=0.0011).

While all percutaneous procedures were preplanned for an overnight hospital stay, it's likely that the procedure could be safely done on an outpatient basis, Dr. Hinshaw said.