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Percutaneous Cryoablation For Tumors

Interventional Solutions

Percutaneous cryoablation, or more simply “cryo”, is a minimally invasive image-guided treatment that destroys (ablates) tumors and other targeted tissue with extreme cold while sparing surrounding healthy tissue.

Q&A

How does percutaneous cryoablation work?

After anesthesia or conscious sedation is administered, one or more cryoprobes (slender needles) are inserted into or near the tumor. The doctor uses CT imaging scans to guide placement and verify that the cryoprobe tip is precisely positioned. Once each cryoprobe is in place, a cryogen (freezing agent) is circulated inside the probe to create a very cold ice ball at the tip. The ice ball encompasses (engulfs) the entire tumor plus a safety margin beyond the tumor edges, which is verified by a CT scan. Once this is accomplished, the doctor will then warm and remove the cryoprobe(s).

How does ice destroy cells and what is left?

Lethal ice destroys tumors with a combination of effects. Basically, freezing dries out cells and damages them beyond repair. It ultimately cuts off the tumor’s blood supply. It leaves behind harmless tissue that is absorbed by the body over time.

What are the advantages of percutaneous cryoablation?

Freezing is a natural process that is typically well tolerated by the body. Typically, cryoablation is associated with less pain during and after the procedure compared to heat-based treatments such as radiofrequency ablation and recovery time is shorter than for surgery1. While no treatment comes with a guarantee of success, a distinctive feature of cryo is its repeatability, if required.2-4

What kinds of conditions can be treated with percutaneous cryoablation?

Kidney, lung and liver tumors:

Percutaneous cryoablation is often used to treat kidney, lung and liver tumors. In kidneys, clinical data shows nearly 100% efficacy for tumors up to 4 centimeters in diameter5.

Painful bone metastases as part of palliative care:

Some bone metastases (cancer that spreads to other parts of the body) become painful, because the tumor at- tacks the bone and creates holes that make the bone thin and weak. As the tumor overtakes the bones, surrounding nerve endings send pain signals to the brain. Cryoablation can be used as a palliative (non-curative) treatment to reduce this pain. Twenty-four weeks after cryoablation for painful bone metastases, 69% of patients report at least a 2-point drop (out of 10) in average pain scores6.

Nerve tissue in pain management:

Cryoablation freezes nerves to provide relief from chronic nerve pain. Cryoablation stops the pain signal by physically damaging the nerve. Nerves are coated by sheaths of basic proteins called myelin. Without this protective outer layer, the nerve can’t communicate with the brain. Freezing the nerve actually destroys that myelin coating7. Freezing painful nerves after chest surgery has shown to significantly reduce pain scores and maintain this effect for weeks to months8.

Who is a candidate for percutaneous cryoablation?

Almost any adult with an unresectable (non-operable) tumor that requires treatment may be a candidate for percutaneous cryoablation. Because many patients can be treated under conscious sedation, patients who cannot receive general anesthesia may also be excellent candidates for cryoablation. Patients with extensive metastatic disease may or may not be candidates for cryoablation. Your doctor will inform you if cryo is appropriate for you.

How long does the procedure take?

Your physician can best answer that question, but a typical percutaneous cryoablation procedure takes about 1 1/2 to 2 hours.

How do I prepare for the procedure?

Your physician will let you know how best to prepare for the procedure. Patients who are taking certain medications, such as blood thinners, may be required to stop several days prior to the procedure. Diet restrictions prior to the procedure and what to bring with you will vary for each person. Check with your doctor for any pre-procedure instructions.

What will happen after the procedure?

Typically, after the procedure you will be taken to a recovery area where you will be monitored for a certain period of time. If your procedure requires you to stay overnight, you will be taken to your room once you can be safely moved. Otherwise, you may be allowed to go home the same day. Most patients may resume their normal routine in a day or two dependent upon their doctor’s advice.

How long is the recovery period?

While each person is different, most patients recover quickly. Typically, patients spend only one night in the hospital or may even go home the same day. Most patients make a full recovery within a week or so. However, as with any medical procedure there are risks, and you should always closely follow your doctor’s advice.

How will my results be monitored?

Your physician will schedule a CT scan shortly after the procedure. Follow-up CT scans may also be used to monitor your progress over time.

What are the risks of percutaneous cryoablation?

As with any medical procedure, there are potential risks and complications related to percutaneous cryo. Your physician will advise you of your specific risks before the procedure.

References

  1. Yılmaz S, et al. Use of cryoablation beyond the prostate. Insights Imaging. 2016;7(2):223-232.
  2. Higgins, LJ, et al. Renal Ablation Techniques: State of the Art. AJR Am J Roentgenol. 2015 Oct;205(4):735-41.
  3. Venkatesan AM, et al. Percutaneous Ablation in the Kidney. Radiology. 2011;261(2):375–91.
  4. Thacker PG, et al. Palliation of painful metastatic disease involving bone with imaging-guided treatment: comparison of patients’ immediate response to radiofrequency ablation and cryoablation. AJR Am J Roentgenol. 2011 Aug;197(2):510-5.
  5. Gunn AJ et al. Society of Interventional Radiology Quality Improvement Standards on Percutaneous Ablation in Renal Cell Carcinoma. J Vasc Interv Radiol. 2020 Feb; 31(2):195-201.
  6. Callstrom MR, et al. Percutaneous image‐guided cryoablation of painful metastases involving bone. Cancer. 2013;119(5):1033-1041.
  7. Hooshmand H, et al. Cryotherapy Can Cause Permanent Nerve Damage: A Case Report. American Journal of Pain Management. 2004; 14: 63-70.
  8. Moore M et al. CT Guided Percutaneous Cryoneurolysis for Post Thoracotomy Pain Syndrome. Academic Radiology, 2010 May; 17(5):603-6.