In recent years, cryoablation for kidney cancer is being adopted as a promising minimally invasive treatment option for early stage RCC. Large studies show comparable oncological outcomes to surgery, with fewer complications and a shorter hospital stay. 
The majority of kidney tumors are small, localized masses. Renal cell carcinoma (RCC) is the most common solid lesion within the kidney accounting for approximately 90% of all kidney malignancies and representing the sixth most frequently diagnosed cancer in men and the 10th in women worldwide.
The lifetime risk for developing kidney cancer in men is about 1 in 46 (2.02%) and about 1 in 80 (1.03%) for women.
Today, partial nephrectomy or nephron sparing (where the surgeon removes the tumor but spares the kidney) has traditionally been considered the “gold standard” for treating resectable diseases.
Cryoablation for kidney cancer
Cryoablation is a minimally invasive procedure that uses extreme cold temperatures to destroy (ablate) benign or malignant tumors. 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. The tissues targeted for destruction and the ice ball that grows around it during the treatment, are visualized using real-time image guidance, allowing a good approximation of the frozen tissue in the ablated area.
As discussed in an earlier blog, more and more renal cell cancers are being detected at an earlier stage, usually at stage T1a or T1b. As a result, percutaneous cryoablation has gained acceptance as a treatment for small renal cancers.
Advantages of cryoablation
Cryoablation brings many advantages for the treatment of kidney cancer. It is a minimally invasive and fast procedure requiring a shorter stay in the hospital versus nephron-sparing surgery. For example, using the ProSense™ (IceCure-Medical Ltd.) liquid nitrogen cryoablation system, a procedure can be performed in as little as 40 minutes, with most patients being able to go home that same day, leading to significant cost benefits for hospitals.
Patients have minimal scarring and procedures are fairly painless with only a mild sedation required because of the analgesic effect of the freezing temperature. Cryoablation is also safe and repeatable enabling further treatment and potentially reducing the impact of higher local recurrence after a single ablation.
Cryoablation is a viable treatment option for patients with multiple comorbidities or those deemed unfit for surgery. 
How effective is cryoablation for kidney cancer?
Cryoablation is considered a safe and effective treatment option for small kidney lesions.
Interim results from a clinical trial (ICE-SECRET) with IceCure’s ProSense™ liquid-nitrogen system demonstrated percutaneous cryoablation for early-stage (T1a) small renal masses (SRMs) was a feasible and safe procedure, with minimal adverse effects and similar oncologic results as Nephron Sparing Surgery (NSS).
At 1 year follow-up of 42 patients with ≤4cm renal masses from 74 patients involved in the trial, results demonstrated:
- 93% of patients were recurrence free
- 92% of patients had no adverse effects.
Cryoablation vs partial nephrectomy (surgery)
When it comes to treating resectable kidney diseases, partial nephrectomy or sparing-nephrectomy, as mentioned, is considered the “gold standard.” In terms of effectiveness, cryoablation has demonstrated similar efficacy outcomes,  with similar local recurrence-free survival rates* and similar metastasis free survival rates. This technique is specifically advantageous in patients with multiple comorbidities and technically complex lesions, who are not good candidates for surgery.
*Metastasis or local recurrence-free survival rates refer to the length of time after primary treatment for a cancer ends that the patient survives without any signs or symptoms of that cancer.
In a 10-years prospective study of percutaneous cryoablation for stage I renal cell carcinoma by Morkos et al (2020), the disease-specific survival was 94% at 5 and 10 years, equivalent to that reported after Radical Nephrectomy or Partial Nephrectomy.
Cryoablation vs radiofrequency ablation
Both cryoablation and radiofrequency ablation are options for patients who elect thermal ablation. Radiofrequency ablation (RFA) is a heat-based ablation technique. Through an interstitial electrode, an alternating electric current is applied to the target tissue. Coagulative tissue necrosis is caused by heat created from using low frequency radio-waves with a long wavelength. Under ultrasound (US) guidance, a needle electrode is inserted percutaneously using image guidance to deliver an alternating current that causes localized tissue heating and cell death.
Current data based on analyzing forty-seven studies representing 1375 kidney lesions treated by cryoablation or RFA, suggests that cryoablation provides superior oncologic outcomes. Cryoablation resulted in fewer retreatments, improved local tumor control, and it may be associated with a lower risk of metastatic progression compared with RFA.
Cryoablation vs microwave ablation (MWA)
MWA uses microwaves to provide intense heat to destroy the tumor, while tissues with lower-water-content such as adipose tissues remain unharmed.
Microwave ablation uses US, computed tomography (CT), or magnetic resonance imaging (MRI) to guide placement of a needle-like probe into a tumor.
Cryoablation has certain procedural advantages over heat-based ablation techniques such as MWA and RFA. It allows the simultaneous use and synergy of more than one probe, thus sculpting the ice-ball.
Cryoablation also has low intraprocedural pain as ice has an analgesic effect versus heat-based techniques which may cause significant pain. It also enables reliable efficacy evaluation as post-ablation boundaries following the procedure are smooth, uniform, and consistent with actual ablation. As compared to MWA that may cause irregular and unpredictable post ablation boundaries due to vascular heat sink effect and conductivity impact.
Clinical effectiveness of cryoablation and MWA are considered comparable. A meta-analysis of fifty-one studies representing 3950 kidney lesions showed there is no difference in local or metastatic recurrence between cryoablation and microwave ablation-treated small renal masses. 
Cryoablation represents an alternative treatment approach for patients diagnosed with kidney cancer. Before undergoing the procedure, a healthcare professional will order an MRI or CT scan to ensure that an individual is a suitable candidate for the procedure.
Typically, patients who have stage T1a or T1b kidney cancer are suitable. Age, kidney function, location and size of the tumor will affect whether cryoablation is suitable.
Based on National Comprehensive Cancer Network (NCCN) guidelines, cryoablation is best suited for treating small renal masses of ≤4cm in patients who are:
- not suitable for surgery
- following a partial nephrectomy
- with a single or transplanted kidney.
Kidney cryoablation success rate & long-term follow-up
There are several retrospective studies supporting the short and midterm outcome and efficacy of percutaneous renal cryoablation.
Results of a long-term, prospective study reported efficacy and safety of percutaneous cryoablation for 265 stage T1a/b renal cancers treated over a period of 5 years. The 5-year cancer specific survival rate was 100% and the 5-year recurrence free survival rate was 97%, with a significant complication rate of 6%, lower than that of other surgical options.
These results are comparable to the gold-standard (partial nephrectomy) in terms of efficacy, and better in terms of safety.
Kidney cancer cryoablation procedure
Kidney cryoablation recovery time
Most patients recover relatively quickly and can go home the same or next day with full recovery often made within a week.
Kidney cryoablation side effects
The most common complications for cryoablation are “Probe site pain” (10.9%), “Bleeding/ Perinephric Hematoma” (4.8-6.2%) and Hematuria (2.8%).
Watch a percutaneous cryoablation procedure of renal cancer using the ProSense™ System here.
Cryoablation for kidney cancer: An overview
There is growing evidence that favors ablation in helping with the treatment of kidney cancer. Generally, ablative techniques have been shown to be a safe and effective way of treating kidney cancer for patients who meet certain selection criteria.
Cryoablation has been shown to be a safe, minimally invasive alternative to surgery that preserves more of the kidney while being able to be repeated more than once in the same area. Furthermore, the patient feels less pain and is released from the hospital usually the same or the next day, resulting in lower hospital costs.
Clinical studies demonstrate that cryoablation has similar efficacy outcomes, with similar local recurrence-free survival rates and similar metastasis-free survival rates to partial nephrectomy.
 Campbell et al, 2017 RENAL MASS AND LOCALIZED RENAL CANCER: AUA GUIDELINE Escudier B, Porta C, Schmidinger M, Rioux-Leclercq N, Bex A, Khoo V, Grünwald V, Gillessen S, Horwich A; ESMO Guidelines Committee. Electronic address: firstname.lastname@example.org. Renal cell carcinoma: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up†. Ann Oncol. 2019 May 1;30(5):706-720. doi: 10.1093/annonc/mdz056. PMID: 30788497.
 2022 EAU-Guidelines-on-Renal-Cell-Carcinoma https://uroweb.org/guidelines/renal-cell-carcinoma
 Mershon JP. et al. Thermal ablation of the small renal mass: a critical analysis of current literature. Minerva Urol Nefrol. 2020 Apr;72(2):123-134. doi: 10.23736/S0393-2249.19.03572-0. Epub 2019 Dec 12. PMID: 31833721
 Georgiades C. et al. Renal tumor ablation. Tech Vasc Interv Radiol. 2013 Dec;16(4):230-8.
 Thompson RH. et al. Comparison of partial nephrectomy and percutaneous ablation for cT1 renal masses. Eur Urol. 2015 Feb;67(2):252-9.
 Morkos J. et al. Percutaneous Cryoablation for Stage 1 Renal Cell Carcinoma: Outcomes from a 10-year Prospective Study and Comparison with Matched Cohorts from the National Cancer Database. Radiology. 2020 Aug;296(2):452-459.
 Maria T & Georgiades C. Percutaneous Cryoablation for Renal Cell Carcinoma. J Kidney Cancer VHL. 2015; 2(3): 105–113.
 Martin J & Athreya S. Meta-analysis of cryoablation versus microwave ablation for small renal masses: is there a difference in outcome? Diagn Interv Radiol. Nov-Dec 2013;19(6):501-7. doi: 10.5152/dir.2013.13070.
 Georgiades CS, Rodriguez R. Efficacy and safety of percutaneous cryoablation for stage 1A/B renal cell carcinoma: results of a prospective, single-arm, 5-year study. Cardiovasc Intervent Radiol. 2014;37(6):1494–9.
 Mershon JP. et al. . Thermal ablation of the small renal mass: a critical analysis of current literature. Minerva Urol Nefrol. 2020 Apr;72(2):123-134. doi: 10.23736/S0393-2249.19.03572-0. Epub 2019 Dec 12. PMID: 31833721