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GALIL MEDICAL LAUNCHES NEW FAMILY OF CRYOABLATION NEEDLES Arden Hills, MN—DATE October 5, 2015 — Galil Medical, the global leader in interventional oncology cryoablation technolo…

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Client Testimonials

I wanted it all out of the way as quickly as possible so that I could get back to work! I chose cryoablation because it was minimally invasive and there was a good chance that my renal [kidney] function could be preserved..

Introduction  |  Patient Selection Guidelines  |  Treatment  
Cryoablation Results  |  Frequently Asked Questions  |  Additional Resources



1. Introduction

Cryoablation, occasionally called cryotherapy or cryosurgery, is a minimally invasive treatment (no incisions) that uses extremely cold temperatures to kill cancer tumors. It is a well-established technology for the treatment of many benign and malignant tumors and lesions, including kidney tumors. Very precise targeting and control of the extremely cold energy allow for efficient destruction of tumor cells while leaving healthy kidney tissue intact and functional.

Kidney Anatomy

The kidneys are a pair of bean-shaped, fist-sized organs, located on either side of the spine just above waist level. As the chief organs of the urinary system, the kidneys are sophisticated reprocessing machines. Every day, the kidneys process about 200 quarts of blood to sift out about 2 quarts of waste products and extra water. The waste and extra water become urine.

Each kidney is composed of about one million microscopic "filtering packets" called nephrons. A complicated chemical exchange takes place in the nephrons as waste materials and water leave the blood and enter the urinary system. Each nephron connects to progressively larger tubular branches, until it reaches a large collection area called the calyx. The calices form a funnel-shape at the upper ureter called the renal pelvis. Urine moves from the renal pelvis through the ureters, the tubes that connect the kidney to the bladder. Urine leaves the body through another tube called the urethra.




Kidney Cancer

Kidney cancer, or renal cancer, is cancer that originates in the kidney. This cancer occurs most often in adults between the ages of 50 and 70, affecting men twice as often as women and is a rare cancer in children and young adults. There are two main types of kidney cancer, renal cell carcinoma (cancer that forms in the lining of the small kidney tubes that filter blood and remove waste) and renal pelvis carcinoma (cancer that forms in the center of the kidney where urine collects). Approximately 90% of adult kidney cancer is renal cell carcinoma (RCC).

Serious health problems occur when kidneys perform below 25% of full renal function. If function drops below 10-15%, some form of kidney replacement therapy is necessary to sustain life, such as dialysis or transplant. Therefore, preservation of maximum renal function is an important consideration in deciding the best treatment, especially if a patient’s kidney function is already below optimal.

a. Symptoms

The majority of kidney tumors are found during routine physical exams or during screening for other conditions. When initially discovered, many of these tumors are relatively small and the patient may not have experienced any symptoms.

The most common symptom of kidney cancer is blood in the urine, called hematuria. This may make the urine rusty or dark red in color. Sometimes the blood is not visible, but is only seen when a urine specimen is examined under a microscope. It may be discovered as part of a routine urinalysis performed during a regular physical exam.

Other symptoms of kidney cancer may include pain in the back or side that does not go away, a lump or mass on the side or the abdomen, unexplained weight loss, fever, feeling very tired, swelling in the legs or ankles, or having a general feeling of poor health. Most often, these symptoms do not indicate cancer. An infection, a cyst, or some other problem in the urinary system can cause these same symptoms.

b. Tests and Staging


If kidney cancer is suspected, laboratory and imaging tests may be conducted to confirm the diagnosis. Laboratory tests may include urinalysis (to look for blood or other substances in the urine), complete blood count (to measure the different cells in the blood), and blood chemistry tests (to evaluate chemicals in the blood and to assess kidney function).

Imaging tests are used to create pictures of the inside of a patient’s body. Energy (x-rays, sound waves, magnetic fields or radioactive particles) is sent through the body; as various body tissues change the energy pattern, a picture is created. These pictures can show normal and abnormal body structures. Computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound are the imaging modalities most commonly used to diagnose kidney tumors. A CT scanner uses x-rays to take multiple pictures as it rotates around the patient. A computer combines the pictures into cross-sectional images of the body that are evaluated by a radiologist. Similarly, MRI scans also provide detailed pictures of the body, but the energy source for MRI scans is a combination of radio waves and strong magnets. Ultrasound devices send sound waves into the body, pick up the echoes that bounce back from kidney tissue and convert the echoes into picture. The pictures created by the selected imaging modality provide information about the size, shape and location of a tumor.


Needle biopsy (removing a sample of tissue for microscopic examination by a pathologist) of a renal mass may be conducted to distinguish between benign lesions and renal cancer. The biopsy may be performed at a time prior to ablation or immediately prior to the ablation.



After a positive kidney cancer diagnosis has been made, a treatment plan must be created. One of the first steps in developing the plan is “staging” the cancer. The stage assigned describes the disease in a way that is understood throughout the medical community.

Renal cell carcinoma is commonly described using the TNM stages.

  • T – Refers to the tumor size and location (T1, T2, T3 or T4).
  • N – Describes whether lymph nodes are affected (N0 or N1).
  • M – Defines whether the cancer has spread beyond the kidney (metastases) (M0 or M1).


The T, N and M stages may be grouped together and described in numerical stages, ranging from I – IV.

  • Stage I – the earliest stage of kidney cancer; the tumor is less than 7cm (about 2-3/4 inches) in diameter (T1), has not spread outside the kidney (M0), and there is no lymph node metastasis (N0). 
    • T1a Tumor ≤ 4 cm in greatest dimension, limited to the kidney
    • T1b Tumor > 4 cm but < 7 cm in greatest dimension, limited to the kidney
  • Stage II – a fairly early stage of disease; the tumor is larger than 7 cm (T2), but the cancerous cells are still confined to the kidney (M0), and there is no lymph node metastasis (N0).
    • T2a Tumor > 7 cm but ≤ 10 cm in greatest dimension, limited to the kidney
    • T2b Tumor > 10 cm, limited to the kidney
  • Stage III – a kidney cancer stage described by one of the following:
    • The tumor has not spread outside the kidney, but cancer cells have been found in one nearby lymph node; or
    • The tumor has invaded the adrenal gland, the fat, and/or the fibrous tissue surrounding the kidney but has not spread beyond the fibrous tissue and cancer cells may be found in one nearby lymph node; or
    • Cancer cells have spread from the kidney to a nearby large blood vessel and cancer cells may be found in one nearby lymph node. 
  • Stage IV – a kidney cancer stage defined by one of the following:
    • The tumor extends beyond the fibrous tissue that surrounds the kidney; or
    • Cancer cells are found in more than one nearby lymph node; or
    • The cancer has spread to a remote area of the body, such as the lungs.

Recurrent cancer is cancer that has come back after treatment. It may be found in the kidney(s) or elsewhere in the body.

For further information, see:

Medicine Net   
National Cancer Institute
Macmillan Cancer Support


2. Patient Selection Guidelines

Cryoablation can be an effective, minimally invasive treatment option for most patients with kidney cancer. Physicians will review a patient’s characteristics, in combination with their experience, to identify candidates appropriate for cryoablation. The benefits and outcomes related to the use of cryoablation allow its use for patients who may be considered unsuitable for other treatment options, including individuals with:

  • Solid, localized kidney tumor masses
  • Multiple co-morbidities (simultaneous disease, medical condition)
  • Inability to tolerate general anesthesia
  • A single kidney
  • Renal insufficiency
  • Multiple renal tumors
  • Tumors that increase in size over a brief period of active surveillance
  • A desire for a non-surgical treatment

Clinical specialty societies (American Urological Association (AUA) and European Association of Urologists (EAU)) and national cancer groups include cryoablation as a treatment option in their guidelines for the management of kidney cancer.


AUA Clinical Guidelines for Management of Renal Mass
EAU Guidelines on Renal Cell Carcinoma
National Comprehensive Cancer Network Kidney Cancer Guidelines


3. Treatment

a. Overview

Cryoablation is a well-established technology for the treatment of many benign and malignant tumors and lesions. Kidney cancer cryoablation destroys the cancerous tissue by freezing the cancer cells. Very precise targeting and control of the extremely cold energy allow for efficient destruction of tumor cells while leaving healthy kidney tissue intact and functional.

b. Cryoablation Procedure

To freeze the cancer, special ultra-thin probes called cryoablation needles are inserted into the site targeted for ablation. Argon gas is delivered under pressure into a small chamber inside the tip of the needle where it expands and cools, reaching a temperature well below -100º Celsius. This produces an iceball of predictable size and shape around the needle. This iceball engulfs the tumor, killing the cancerous cells as well as a small margin of surrounding tissue while sparing healthy kidney structures.

Ultra-thin thermal sensors may also be placed at the margin of the tumor to monitor tissue temperature and help ensure that the entire tumor is destroyed.

c. Cryoablation Approaches

A couple of approaches can be used to perform renal cancer cryoablation, so the physician can customize the treatment to accommodate the patient’s general health as well as the size and location of the tumor. A minimally invasive approach, rather than an open surgical approach, is usually preferred.

Percutaneous Approach

The minimally invasive approach most frequently chosen is percutaneous ablation. With percutaneous access, no incisions are made. The patient is positioned in a CT (computerized tomography) or MRI (magnetic resonance imaging) scanner. The cryoablation needles and thermal sensors are inserted through the skin and positioned in the tumor under the image guidance of CT, MRI or ultrasound and the entire procedure is monitored using CT or MRI. Image-guided percutaneous cryoablation may be performed under conscious sedation, local anesthesia, or general anesthesia.

Laparoscopic Approach

Laparoscopic-guided kidney cryoablation, also a minimally invasive approach, is conducted using 3-4 small incisions through which instruments are inserted. A laparoscopic ultrasound probe is inserted through one of these incisions to send images to a screen so the physician can visualize the kidney, appropriately position the cryoablation needles, observe the iceball formation and ensure tumor destruction. Laparoscopic cryoablation is almost always performed under general anesthesia.

Open Surgery

Renal cryoablation can also be performed during traditional open surgery, although this approach is rarely used today.

4. Cryoablation Results

a. Patient Benefits

Minimally Invasive

An advantage of kidney cryoablation is that the procedure can be conducted percutaneously (directly through the skin), thus making it a minimally invasive procedure. The minimally invasive nature of the procedure means that it can be performed with minimal blood loss and without a large incision. A minimally invasive procedure, compared to an open surgical procedure, can mean significantly less pain, a shorter hospital stay, and more rapid recovery. As a minimally invasive procedure, cryoablation allows kidney cancer to be treated with much less disruption of patients’ lives. Patients usually are able to return to family, work, and routine activity in less than half the time that it takes to recover from an open surgical procedure.

Shorter Procedure with Fewer Complications

Patients who undergo cryoablation have less risk of experiencing some surgical complications, such as bleeding. The risk of excessive bleeding is decreased by not having to cut into the kidney as is typically done with a surgical procedure on the kidney, such as a partial or radical nephrectomy. Similarly, not cutting into the kidney minimizes the risk of disrupting the kidney’s collection system (the “plumbing” within the kidney which transports urine), which is a complication known as “urine leak.”

Preservation of Normal Kidney Tissue

Kidney cancer treatment that maintains adequate renal function is of the utmost importance to the patient’s ongoing quality of life. Because only the cancer is destroyed during cryoablation and normal kidney tissue is spared, remaining renal function is maximized. This means that the kidneys can continue to perform their many jobs more efficiently than if the entire kidney, or a significant part of it, had been removed.

In addition, sparing a portion of the affected kidney creates more options should a new tumor develop in the patient's second kidney, a risk confronting a small number of people with kidney cancer.

Cryoablation is Repeatable

In most cases, image-guided targeted ablation and real time temperature monitoring assure that only one session of cryoablation is necessary. Should the patient’s cancer recur, or if residual tumor is found on follow-up visits, renal cryoablation can be repeated with minimal trauma to the patient.

b. Outcomes

Local Tumor Control

Local tumor control describes how well the cancer has been destroyed or limited in the target tissue. A high number means more effective control at the time of follow-up.

Numerous studies document cryoablation efficacy for local tumor control after a single treatment. Clinical evidence documents oncologic outcomes following cryoablation are comparable to the oncologic outcomes following partial nephrectomy.



 Chart References

c. Complications

There are complications possible with any medical procedure and renal cryoablation is no exception. Complications that can occur during or after any procedure include problems related to general anesthesia and cardiovascular problems such as heart attack, stroke, deep vein thrombosis and pulmonary embolus. These problems rarely occur, and the risk depends on the patient’s general fitness for surgery and previous medical problems. Published data show that the location and size of the lesion can affect the risk for certain complications, as can the approach and technique employed to access the kidney. Overall, minimally invasive procedures have a lower complication rate than open surgeries.

Patients treated with cryoablation, compared to patients undergoing surgery, have less risk of bleeding because the physician is not actually cutting into the kidney. Similarly, not incising the kidney minimizes the risk of a complication known as “urine leak.” As used here, the term “urine leak” refers to urine leaking from the kidney’s internal collection system. This happens when the collection system is disrupted by the incision made into the kidney.

During the double freeze-thaw process of cryoablation, injury to nearby structures such as the blood vessels, spleen, liver, pancreas or bowel can occur. Great care is taken during every cryoablation procedure to avoid these injuries, and pre-procedure imaging studies aid the physician in planning the best approach, technique, and placement of the cryoablation needles to minimize trauma to healthy kidney tissue and adjacent structures.

Since patients undergoing cryoablation to destroy a kidney tumor report minimal pain, complications arising from the administration of pain killers are also kept to a minimum.

d. Follow-up Care

Recovery time and specific follow-up care will vary significantly depending on the approach, technique, and type of anesthesia used for the renal cancer ablation. However, there are some typical expectations.

After the procedure, the patient is taken to a recovery area, where vital signs and urinary output will be closely monitored. In most cases, many patients experience very little discomfort after an image-guided percutaneous procedure, but each case is treated on an individual basis with the goal of keeping the patient as comfortable as possible. Pain relief may be needed following an open or laparoscopic cryoablation procedure.

Patients remain in the hospital until they are eating, drinking, walking, and urinating satisfactorily. Again, depending on the approach, technique and anesthesia, this can vary from several hours, as in the case of an uneventful percutaneous kidney cryoablation, to a couple of days, in the case of cryoablation performed during an open surgical procedure. Should complications occur, it is possible that a longer hospital stay may be necessary.

There are several effective treatment protocols and standards of care that physicians follow for kidney cancer patients. CT or MRI scans will be repeated periodically to assess the effectiveness of the treatment.

5. Frequently Asked Questions

How is cryoablation performed?

There are two approaches typically used to treat kidney tumors with cryoablation; the type chosen will depend on the physician’s judgment, and the location and size of the tumor(s) to be treated. The majority of kidney cryoablation procedures performed are percutaneous procedures. Alternatively, a laparoscopic procedure may be performed. In either approach, the needles are inserted percutaneously.

What is percutaneous kidney cryoablation?

Percutaneous procedures are procedures in which access to the target tissue (e.g. kidney) is gained by needle(s) inserted through the skin. Percutaneous kidney cryoablation uses very thin needles, inserted through the skin to the kidney.

What is an image-guided procedure?

An image-guided procedure uses CT (computerized tomography), MR (magnetic resonance) or, occasionally, ultrasound imaging technology to give the doctor a clear view on a screen of the area to be treated. The imaging technology allows the doctor to accurately insert the cryoablation needles through the skin into the kidney tumor, carefully position the needles and control the creation of the ice to help make sure the entire tumor is treated.

What is laparoscopic kidney cryoablation?

A laparoscopic, or keyhole, procedure is performed through three or four small incisions placed into the patient. A tiny camera is inserted into the abdominal cavity through one of these small incisions and sends images to a screen. The camera allows the doctor to have excellent visibility to position the needles and to accurately control the size, shape and location of the ice. The position and size of the ice will also be checked by a special ultrasound scan to help make sure the entire tumor is treated.

What happens to the tumor once it has been frozen?

The cryoablation freezing process destroys the cells in the tumor. There is no need to remove this dead tissue as the body’s own immune system recognizes the cells are dead and sends white blood cells to clear them away. Once the clearing process is complete, only scar tissue remains where the tumor was previously located.

Does cryoablation cure kidney cancer?

For patients considered suitable for kidney cryoablation, it is likely that the procedure will effectively treat kidney cancer.

Numerous clinical studies have demonstrated that cryoablation successfully destroyed the cancer in the targeted tumors.

Who is suitable for cryoablation?

Physicians experienced in cryoablation procedures can identify who is a suitable candidate for cryoablation. The size and location of the tumor(s), the patient’s general health and the patient’s preference will all be factors in the decision.

Cryoablation may be used to treat a range of tumor sizes and locations within the kidney. Published data provide evidence that the oncologic outcomes following cryoablation are comparable to oncologic outcomes following partial nephrectomy and are superior to outcomes following radiofrequency ablation. Cryoablation can be performed under conscious sedation with local anesthesia, providing an alternative therapy for patients at risk for use of general anesthesia. For patients who are at risk for complications of surgery, cryoablation offers an alternative with low risk of bleeding or other complications. Patients who have poor kidney function, Von Hippel-Lindau syndrome or a single kidney may also be good candidates for cryoablation.

How long does the procedure take?

Although each case is different, a percutaneous kidney cryoablation procedure usually lasts approximately one hour; other cryoablation approaches will be longer.

How much pain is associated with cryoablation?

Many patients experience very little pain associated with cryoablation, but some patients may have some discomfort. If appropriate, pain medicines may be given to improve patient comfort.

How long is the hospital stay?

Many doctors prefer their patients to stay in the hospital for at least one night after the procedure. This allows the doctor to make sure patients are eating, drinking, walking and urinating satisfactorily before being discharged from the hospital. Of course, if there are any complications, patients may need to stay in the hospital longer, and local arrangements may vary.

What is the recovery time before returning to work?

Recovery time will depend on the extent of the disease treated, the approach used, the patient’s general health and the patient’s type of work. Most patients who do not have physically demanding jobs are able to return to work within two weeks.


6. Additional Resources

a. Definitions

Ablation: The destruction of tissue by the application of extreme cold, heat or light (laser).

Anesthesia: The loss of sensations and usually of consciousness artificially produced by the administration of one or more agents to block the passage of pain impulses along nerve pathways to the brain.

Benign: Without cancer; not cancerous.

Biopsy: The removal and examination of a sample of tissue for diagnostic purposes.

Calyx / calices: Chambers within the kidney through which collected urine passes to the renal pelvis.

Cancer: A malignant and invasive growth or tumor.

Comorbidity: The presence of one or more additional diseases or disorders occurring simultaneously with a primary disease or disorder.

Computed tomography (CT): A non-invasive imaging procedure that uses computer processed x-rays to create a series of detailed pictures (slices) of areas inside the body.

Conscious sedation: The technique of using medicines to create a relaxed state and to block pain during a medical procedure; intended to allow the patient to stay awake yet be comfortable during the procedure.

Cryoablation or Cryotherapy or Cryosurgery: The destruction of tissue by the application of extremely cold temperatures.

Cyst: A cluster of cells that form a sac and have a distinct surrounding membrane.

Hematuria: Presence of blood in the urine.

Image-guided procedure: A procedure that correlates real-time images created during a procedure (e.g., CT or MRI) with preoperative images.

Kidney cancer: Cancer that originates in the kidney.

Laparoscopic procedure: A surgical technique in which small incisions allow performing a procedure without major incisions; a small video camera is inserted through a small incision to inspect tissue or to observe a surgical procedure; surgical tools are inserted through other small incisions to perform a procedure.

Lymph node: Small, bean-shaped organs which filter bacteria and foreign particles and contain immune cells that fight infections and disease; lymph nodes are located throughout the body.

Magnetic resonance imaging (MRI): A non-invasive imaging procedure that uses a powerful magnetic field, radio frequency pulses and a computer to produce detailed pictures of areas inside the body.

Metastases: New occurrences of cancer that have spread from the original cancer site to another organ or tissue not directly connected to the original site.

Minimally invasive procedure: A procedure that is performed through tiny incisions or needle punctures rather than a large incision; recovery time may be quicker and these procedures may produce less discomfort than conventional, open surgical procedures.

Nephron: The basic structural and functional unit of a kidney; responsible for regulating the concentration of water and soluble substances in blood by filtering blood, removing waste and excess substances to be excreted as urine.

Oncology: The branch of medicine dealing with tumors, including the diagnosis, development, and treatment of malignancies.

Oncologic: Of or relating to oncology; practicing oncology.

Partial nephrectomy: A surgical procedure to remove only the cancerous tumor or diseased portion of the kidney, leaving intact healthy kidney tissue

Percutaneous: A medical procedure in which access to the target tissue is gained using a needle puncture through the skin, rather than using an incision into the skin.

Radiofrequency ablation: A procedure to destroy target tissue with heat using high-frequency electrical energy delivered through a needle

Recurrent cancer: The return of cancer after treatment and after a period of time during which the cancer was not detected.

Renal cancer: Cancer that originates in the kidney.

Renal cell carcinoma: Cancer that forms in the lining of the small kidney tubes that filter blood and remove waste; approximately 90% of kidney cancer is renal cell carcinoma (RCC).

Renal pelvis carcinoma: Cancer that forms in the center of the kidney where urine collects.

Ultrasound imaging: A non-invasive imaging procedure that uses high-frequency sound waves to produce real-time pictures of areas inside the body.

Ureter: The tube that carries urine from a kidney to the bladder.

Urethra: The tube that carries urine from the bladder to be discharged outside the body.

Urinalysis: The microscopic, physical and chemical examination of urine to evaluate the compounds in the urine.

Urine leak: A complication of kidney surgery that results in urine leaking from the kidney’s internal collection system.

Von Hippel-Lindau syndrome: A rare, inherited disorder that predisposes individuals to form tumors and cysts in the body; the tumors may be benign or malignant.

b. Clinical Publications


Galil Medical is a global leader in delivering innovative cryotherapy solutions. We focus primarily on the ablation of solid tumor cancers and nerve ablation for pain management. Our products address a range of cancers including kidney, lung, bone, liver and prostate as well as several local pain and nerve conditions. Our customers include multiple physician specialties — primarily Interventional Radiologists, Interventional Oncologists and Urologists.


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