Protection from injury of organs adjacent to a renal tumor during percutaneous cryoablation

Is cryoablation a valid option for renal cell carcinomas in direct contact with critical organs?

PURPOSE

This study aimed to assess the outcomes of percutaneous cryoablation (PCA) for renal cell carcinomas (RCCs) contacting critical organs without intervening fat tissue.

MATERIAL AND METHODS

Twenty-three patients with 24 RCCs (mean size, 28.8 mm) contacting critical organs on preprocedural images were included. The organ displacement techniques, technical success, efficacy, and adverse events per Clavien-Dindo classification were retrospectively reviewed.

RESULTS

The organs contacting the RCCs included the colon (n = 16), pancreas (n = 3), duodenum (n = 3), small intestine (n = 1), and stomach (n = 1). In all procedures, hydrodissection was conducted, and probe traction was additionally utilized in one to displace organs. Two procedures were terminated with an insufficient ice-ball margin (<6 mm) due to recurring proximity of the colon or thermal sink effect by renal hilar vessels, yielding a technical success rate of 91.6% (22/24). No severe adverse events were noted. All patients were alive without any metastases during a median follow-up of 34.4 months. The primary and secondary technical efficacy rates were 91.6% (22/24) and 95.8% (23/24) of tumors, respectively.

CONCLUSION

PCA can be a valid option for RCCs contacting critical organs with a good safety profile and sufficient technical efficacy.

Effects of percutaneous cryoablation for renal tumor on overall and split renal function

PURPOSE

To evaluate retrospectively the influence of percutaneous cryoablation for small renal tumors on total and affected kidney function and risk factors associated with worsening function of the affected kidney.

MATERIALS AND METHODS

Between April 2016 and March 2022, 27 patients who underwent cryoablation for small renal tumors at our institution participated in this study, which investigated time-dependent changes in postoperative renal function. We evaluated estimated glomerular filtration rates (eGFRs) and split renal function revealed by scintigraphy using 99 m technetium-mercaptoacetyltriglycine (99mTc-MAG3) before cryoablation and at 1 week, 1 month, and 6 months after cryoablation. Numerous variables were analyzed to assess risk factors for worsening renal function.

RESULTS

Baseline eGFR (mean ± standard deviation) was 56.5 ± 23.7 mL/min/1.73 m2 (mean ± SD; range, 20.5-112.5). Mean eGFRs at 1 week, 1 month, and 6 months after cryoablation were 57.4 ± 24.5 (19.1-114.9), 57.1 ± 25.1 (21.5-114.9), and 53.8 ± 23.9 mL/min/1.73 m2 (20.0-107.5), respectively. Changes were statistically insignificant (p = 1.0000, = 0.6749, and = 0.0761, respectively). Regarding split renal function, mean baseline contribution of the affected kidney determined by 99mTc-MAG3 was 49.7% ± 6.0% (38.8-63.3%); these rates at 1 week, 1 month, and 6 months after cryoablation were 43.7% ± 8.8 (29.1-70.6%), 46.2% ± 7.7% (32.6-70.3%), and 46.0% ± 8.5% (32.5-67.6%), respectively. Differences from baseline were significant for all periods (p < 0001, < 0001, = 0.0001, respectively). Serum C reactive protein and lactate dehydrogenase at 1 day following cryoablation, tumor's nearness to the collecting system or sinus, and volume of ablated normal renal parenchyma were significantly correlated with decreased contributions of the affected kidney by > 10% after cryoablation.

CONCLUSION

Unlike total renal function, affected kidney function could worsen after cryoablation.

Ablation of Kidney Tumors in Patients with Substantial Kidney Impairment: Current Status

PURPOSE OF REVIEW

To review the current status of kidney tumor ablation in patients with substantial kidney impairment.

RECENT FINDINGS

Few reports of kidney tumor ablation in such patients have recently been published. The reported prevalence of patients with stage 4 or 5 chronic kidney disease (CKD) among patients undergoing ablation is 2.0%-10%. In patients with stage 4 or 5 CKD, local tumor control rates were 88%-100%. The effect of ablation on CKD stage is unclear, and the observed deteriorations in kidney function are consistent with both the effect of cryoablation and the natural course of advanced CKD. According to guidelines, active surveillance may be selected. The goals of treatment are complete tumor removal and maintenance of kidney function, both of which can be met by ablation. Given the limited treatment options, ablation may play a pivotal role in the management of patients with advanced CKD.

Hydrodissection During Computed Tomography-Guided Cryoablation for Renal Tumors: Where is the Effective Fluid Accumulation Space in the Retroperitoneum?

PURPOSE

This study was performed to investigate the effectiveness of hydrodissection during computed tomography-guided renal cryoablation by evaluation of the fluid distribution based on the retroperitoneal anatomy with the interfascial plane.

MATERIALS AND METHODS

Between March 2014 and March 2021, 52 renal tumors were treated by cryoablation with hydrodissection (36 men; mean age 72.5 years). The hydrodissection needle was located in perirenal space. The spreading fluid space based on the retroperitoneal anatomy with the interfascial plane was retrospectively evaluated. The fluid space that most effectively separated the tumor from the adjacent organs was defined. The relationship of the needle tip position in the perirenal space (renal capsule or fascia side) and the most effective fluid space was also evaluated.

RESULTS

Cryoablation was successfully completed in all cases with no major complications. Hydrodissection was effective in all cases. The distance between the tumors and the adjacent organs was significantly longer after hydrodissection (from 7.50 ± 7.43 to 22.6 ± 9.86 mm) (P < 0.0001). Although fluid spreading through multiple retroperitoneal spaces was frequently observed, the retromesenteric plane was observed more frequently as the most effective fluid space (67.3%) than the perirenal space (21.2%) (P < 0.0001). Regardless of the needle tip position, the most effective fluid space was also commonly the retromesenteric plane.

CONCLUSIONS

The retromesenteric plane could be the most effective fluid space to separate the tumor from the adjacent organ, regardless of where the hydrodissection needle tip is positioned in the perirenal space.

LEVEL OF EVIDENCE

3b.

Perioperative, functional, and oncologic outcomes of minimally-invasive surgery for highly complex renal tumors (RENAL or PADUA score ≥ 10): an evidence-based analysis

The primary objective of the current study is to undertake a comparative analysis of the effectiveness and safety of minimally-invasive partial nephrectomy (MIPN; including laparoscopic and robotic approaches) and open partial nephrectomy (OPN) for the treatment of highly complex renal tumors (defined as PADUA or RENAL score ≥ 10). A comprehensive search was conducted in four electronic databases (PubMed, Web of Science, Embase, and Cochrane Library) to identify relevant studies published in the English language up to April 2023. The current study employed Review Manager 5.4 and encompassed controlled trials of both MIPN and OPN for the treatment of highly complex renal tumors. This study comprised a total of eight comparative trials involving 1161 patients. MIPN demonstrated a significant reduction in length of hospital stay (weighted mean difference [WMD] - 2.08 days, 95% confidence interval [CI] - 2.48, - 1.68; p < 0.00001), blood loss (WMD - 39.86 mL, 95% CI - 75.32, - 4.39; p = 0.03), transfusion rates (odds ratio [OR] 0.30, 95% CI 0.13, 0.71; p = 0.006), and overall complications (OR 0.46, 95% CI 0.31, 0.70; p = 0.0003). However, there were no significant differences between MIPN and OPN in terms of operative time, warm ischemia time, conversion to radical nephrectomy rates, renal functional and oncologic outcomes. This study reveals that MIPN presents several benefits in comparison to OPN, including decreased length of hospital stay, blood loss, transfusion rates, and complications, while still offering renal functional and oncological outcomes that are comparable to those of OPN in patients with highly complex renal tumors.

Feasibility and Safety of Single-Probe Cryoablation with Liquid Nitrogen: An Initial Experience in 24 Various Tumor Lesions

Simple Summary

Percutaneous cryoablation was developed to minimally perform multi-organ tumor ablations. The most widely known cryotherapy systems use argon gas (high-pressure) and multiple needles to achieve sufficient ablations. The aim of our retrospective study was to assess the feasibility of a new cryotherapy system using single-probe liquid nitrogen for tumor lesions of various sizes and locations, and to evaluate the safety of cryoablation with this technique. Correlations between ice ball sizes and ablation zone sizes with two needle sizes (10G or 13G) and with the freezing duration were evaluated, as well as the sphericity of the ice ball and ablation zones. We showed that this technique is safe in all organs tested. We showed a correlation between the freezing duration and the ice ball size, but not with the ablation zone, which is useful for planning the procedure and treatment conducted by the oncology team.

Abstract

Background: Percutaneous cryoablation with liquid nitrogen is a new technique being used in the treatment of some malignant tumors. Our objective was to assess its feasibility in the ablation of tumor lesions of various sizes and locations. Methods: This retrospective, monocentric study included all consecutive patients who underwent percutaneous cryoablation with liquid nitrogen between December 2019 and March 2021. Cryoablation was performed using 10G or 13G cryoprobes. The ablation volume was measured on post-treatment CT or MRI. Results: 22 patients (24 lesions) were included, 16 of whom were men (73%), while median age was 66 years. The lesions were located in the bone (42%), kidney (29%), soft tissue (17%), lung (8%), or liver (4%). It was feasible in all tumor locations and produced median ablation zones 25 mm in width and 35 mm in length, with a 23 min median freezing time. Freezing duration was correlated with the ice volume (p Spearman = 0.02), but not with the ablation volume (p = 0.11). The average difference between the ablation zone and ice ball sizes were −6.4 mm in width and −7.7 mm in length. Both ice and ablation volumes were larger when using the 10G probe as compared to when the 13G was used. No complications were reported. Discussion: We showed that this technique was safe and feasible in all organs tested. The freezing duration was correlated with the ice ball size, but not with the ablation zone.

Computed Tomography Image under Three-Dimensional Reconstruction Algorithm Based in Diagnosis of Renal Tumors and Retroperitoneal Laparoscopic Partial Nephrectomy

This study was to explore the clinical application value of computed tomography (CT) images based on a three-dimensional (3D) reconstruction algorithm for laparoscopic partial nephrectomy (LPN) in patients with renal tumors. 30 cases of renal cell carcinoma (RCC) patients admitted to the hospital were selected as the research objects and were rolled into two groups using a random table method. The patients who received PLN under the three-dimensional reconstruction and laparoscopic technique were included in the experimental group (group A), and the patients who received LPN using CT images only were included in the control group (group B). In addition, the treatment results of the two groups of patients were compared and analyzed. Results. The effective rate of the established model was 93.3%; the total renal arteriovenous variability of group A (13.3%) was higher than that of group B (6.7%), and the operation time (131.5 ± 32.1 minutes) was much lower than that of group B (158.7 ± 36.2 minutes), showing statistical significance (P < 0.05). Conclusion. CT images based on 3D reconstruction algorithms had high clinical application value for LPN in patients with renal tumors, which could improve the efficiency and safety of LPN.

Impact of Laparoscopic Partial Nephrectomy and Open Partial Nephrectomy on Outcomes of Clear Cell Renal Cell Carcinoma

Objective: To analyze the impact of laparoscopic partial nephrectomy (LPN) and open partial nephrectomy (OPN) on outcomes of complex clear cell renal cell carcinoma (ccRCC).

Methods: A total of 132 high-complex ccRCC patients with a Radius Exophytic Nearness Anterior Location (R.E.N.A.L) score ≥7 enrolled in our hospital between January 2018 and June 2020 were matched and assigned to an LPN group (given LPN treatment) and an OPN group (given OPN treatment), with 66 cases in each group. Two weeks and 3 months after the operation, the renal indexes, inflammatory factors, basic perioperative conditions, and incidence of complications were compared.

Results: Two weeks after the operation, the levels of SCr and CysC were elevated, with higher levels observed in the LPN group (all P < 0.05), and the eGFR levels were reduced, with a lower result in the LPN group. Three months after the operation, the two groups observed decreased levels of SCr and CysC, and an increased level of eGFR; moreover, the decreased SCr and CysC levels were still higher, and the increased eGFR was lower than those before the operation (P < 0.05). The levels of CRP and TNF-α in the two groups increased after the operation, with a lower outcome in the LPN group (P < 0.05). Moreover, the LPN group had less intraoperative blood loss and shorter postoperative length of hospital stay but longer blocking time compared to the OPN group (P < 0.05). Patients in the LPN group were recorded with a lower complication incidence compared with the OPN group (3.03 vs. 15.15%, P < 0.05).

Conclusion: Both LPN and OPN enjoy significant efficacy in the treatment of complex ccRCC and effectively protect renal function. Moreover, LPN is a more acceptable option for complex ccRCC due to its numerous benefits in postoperative stress response, complications, recovery. which is worthy of promotion with safety and feasibility.

Percutaneous Image-guided Thermal Ablation for Renal Cell Carcinoma

Nephrectomy is the gold standard for the treatment of renal cell carcinoma (RCC). However, some patients are not suitable candidates for nephrectomy because of high surgical risk, reduced renal function, or the presence of multiple renal tumors. Percutaneous image-guided thermal ablation, including cryoablation and radiofrequency ablation, is a minimally invasive and highly effective treatment and can be used to treat RCC in patients who are not good candidates for surgery. This article will review percutaneous image-guided thermal ablation for RCC, covering treatment indications, ablation modalities and techniques, oncologic outcomes, and possible complications. In addition, the characteristics of each ablation modality and its comparison with nephrectomy are also presented.