Traditionally the only way to remove a tumor was through surgery, an invasive procedure for the patient. However, technological advancements in the last few decades have provided a whole host of new approaches, and one of those exciting tools is cryoablation.
Cryoablation provides a safe, effective, and minimally-invasive approach to destroy tumors of the breast, lung, kidney, bone, liver and is one method for providing palliative care.
What is cryoablation therapy or treatment?
Cryoablation is a minimally invasive procedure that uses extreme cold temperatures to destroy (ablate) benign or malignant tumors. The tissues targeted for destruction are visualized using imaging guidance such as ultrasound or computed tomography (CT). An extremely cold freezing agent (liquid nitrogen, liquid nitrous oxide, or compressed argon gas) is administered through a thin needle called a cryoprobe in a closed-loop system, freezing and destroying the abnormal tissue.
During a cryoablation procedure, one or more cryoprobes are inserted into the affected area after anesthesia or conscious sedation has been administered. Ultrasound or CT imaging scans are used to guide placement and ensure that the cryoprobe tip is properly positioned. The freezing agent is circulated within the cryoprobe once it has been inserted, creating an ice ball around the targeted tissue. CT scans verify that the ice ball covers the entire tumor as well as a margin of healthy tissue to ensure the area was completely treated. Once this has been accomplished, the cryoprobe is warmed by the cryoablation system and safely extracted from the patient.
WHEN IS CRYOABLATION AN OPTION?
Cryoablation can effectively treat a wide range of benign and malignant tumors, including cancers of the lung, kidney, breast, bone, liver, and some others. The ability to treat the tumor will depend on a number of factors including the type of tumor, location, size, and how well the tumor can be seen under image-guidance.
Metastatic cancers (where the cancer spreads to another part of the body) may be treated with cryoablation to alleviate pain and other symptoms. When a patient is unsuitable for surgical removal of a tumor due to various reasons including advanced age, or other comorbidities, this type of treatment is often recommended.
HOW LONG DOES A CRYOABLATION PROCEDURE TAKE?
A typical percutaneous cryoablation procedure can take about 1 1/2 to 2 hours. Depending on the type of tumor and the location, such as in the case of treating breast tumors, that time can be shortened to 15-45 minutes.
WHAT ARE THE RISKS OF CRYOABLATION?
Cryoablation therapy is generally very safe and the risks involved are generally lower than compared to surgery. There is a small risk of bleeding, infection, and accidental damage to nearby, healthy organs, as with all medical procedures.
WHAT HAPPENS TO A TUMOR AFTER CRYOABLATION?
With a combination of effects, lethal ice destroys tumors. Freezing basically dries out cells and causes them irreparable damage. As a result, blood flow to the tumor is cut off. The necrotic tissue is slowly absorbed by phagocytotic activity of the inflammatory cells. Phagocytosis is a process in which inflammatory cells such as macrophages, neutrophils, eosinophils, and mast cells engulf and remove unwanted cells. Eventually the necrotic tissue is replaced by a fibrous, collagenous scar over the next few weeks and even months.
HOW IS CRYOABLATION TOLERATED BY PATIENTS?
The body typically tolerates freezing well because it is a natural process. A cryoablation procedure usually involves less pain and shorter recovery times than heat-based treatments like radiofrequency ablation. An additional advantage of cryoablation is that it can be repeated if required.
CRYOABLATION FOR BREAST TUMORS
Cryoablation therapy has been increasingly used to treat breast tumors over the last two decades and is a new hope in breast care.
Clinical trials support the use of cryoablation to treat benign breast tumors called fibroadenomas. The American Association of Breast Surgeons considers it “… a successful option for the resolution of fibroadenomas without surgical excision.”
For the treatment of breast cancer, there are exciting cryoablation studies underway in the USA and clinical experience globally supports its use. One such trial is the landmark ICE3 study. This is the largest controlled multi-site clinical trial ever performed for liquid nitrogen (LN2)-based cryoablation of small, low-risk, early-stage breast tumors without the need for surgical excision afterwards.
The ICE3 trial began in 2014, with 206 patients enrolled and treated with a duration procedure of 20-40 minutes, the ICE3 trial has shown promising interim results. At a mean of 34.83 months following treatment with the cryoablation system, ProSense®, only 2.06% (4 patients out of the 194 followed from the 206 enrolled) experienced cancer recurrence.
CRYOABLATION FOR LUNG CANCER
Lung cancer patients are increasingly undergoing percutaneous cryoablation in recent years. A number of studies have also been conducted. The percutaneous imaging-guided cryoablation of lung cancer is a minimally invasive procedure for treating medically inoperable early-stage lung cancer (stage I non-small-cell lung carcinoma (NSCLC)) and for debulking advanced-stage tumors.
The minimally invasive procedure is considered safe and effective, with a good overall long-term survival and minimally significant complications. A recent study followed 101 patients on average for 35 months with stage T1N0M0 non-small cell lung cancer treated with the ProSense™ Cryoablation System. Investigators found cryoablation using liquid nitrogen to be a promising treatment with local control and recurrence-free survival of cryoablation satisfactory for tumors <1.8 cm.
CRYOABLATION FOR KIDNEY CANCER
Renal cell carcinoma (RCC) is one of the most common types of kidney cancers in adults. Resection of the nephron sparingly or partial nephrectomy (where the surgeon removes the tumor but spares the kidney) has been considered the “gold standard” for treating resectable diseases. Increasingly, renal cell cancers are being detected at an early stage, usually at stage 1A or 1B, because of the widespread use of cross-sectional imaging techniques. In recent years, percutaneous cryoablation has gained acceptance as a cure for small renal cancers.
A press release published in the Radiological Society of North America (RSNA) reporting on a study in 2020 described cryoablation as comparable to surgery for treating early-stage kidney cancer, with one doctor commenting:
“For certain patients, cryoablation is equivalent to surgery with fewer side effects. The risk of significant complications from this minimally invasive procedure [in treating early-stage kidney cancer] is about 6%, compared to between 15% and 20% for surgery. In addition, recovery is much faster than with surgery.”
CRYOABLATION AND IMMUNOTHERAPY
Cryoimmunology, also referred to as cryoimmunotherapy, is a form of cancer treatment for various cancers that combines cryoablation of the tumor with immunotherapy treatment .
Early studies are showing an exciting synergetic response of cryoablation together with immunotherapy. It is thought that cryoablation may have an additional role beyond “just” tumor destruction to harness the patient’s own immune system to fight cancer. Together with immunotherapy, cryoablation can generate a synergy, an effective tumor vaccine that can cause resolution of the ablated area and create a systemic response that eradicates all visible disease. This makes cryoablation and immunotherapy an exciting new treatment strategy currently being evaluated for its efficacy, particularly in metastatic patients.
Studies are also showing that cryoablation is effective in controlling cancer pain without relevant side effects.
WHAT’S NEXT FOR CRYOABLATION?
There are many exciting opportunities for patients being treated with cryoablation. Clinical trials and global clinical use demonstrate it is a safe, effective treatment option for a wide variety of tumors. IceCure Medical currently has ongoing clinical trials and independent studies around the world to build further support for the safety and efficacy of cryoablation procedures performed with the ProSense Cryoablation System.
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*** IceCure Medical’s ProSense Cryoablation System has worldwide distribution. Please check that the clinical indications discussed in this blog are cleared for use in your country.***t