Percutaneous Renal Cryoablation Research Articles

Same-day discharge after percutaneous renal cryoablation and its effect on 30 day hospital re-admission rates and post-procedural complications

PurposeThe purpose of this study is to identify if the local institutional shift from routine overnight observation to same-day discharge following percutaneous cryoablation (PCA) of renal tumors increases 30 day re-admission rates or serious adverse events (AEs). Materials and methodsThis retrospective study included 133 adult patients. PCA patients in calendar years 2018-2019 were routinely observed overnight in the hospital, comprising the control group (Group A). PCA patients in calendar years 2021-2022 were routinely discharged the same day, comprising the test group (Group B). Relevant demographic information, tumor characteristics, technical outcomes, and clinical outcomes were recorded. Results15 patients (11.3 %) from the total cohort were re-admitted to the hospital within 30 days of PCA for any reason. Seven patients (10.4 %) and eight patients (12.1 %) were re-admitted for any reason within 30 days in Group A and Group B, respectively, with no difference between the two groups (p = 0.76). Nine patients (6.8 %) from the total cohort were re-admitted to the hospital within 30 days for a diagnosis secondary to the procedure. Four patients (6 %) and five patients (7.6 %) were re-admitted within 30 days for reasons related to PCA in Group A and Group B, respectively, with no significant difference between the groups (p = 0.71). Eight patients (12 %) and four patients (6 %) had major AEs following PCA in Group A and Group B, respectively, with no difference between the two groups (p = 0.43). ConclusionOverall, the change in post-procedural care after PCA did not have a deleterious effect on 30 day re-admission rates or rates of major AEs.

Safety and Technical Feasibility of Percutaneous Renal Cryoablation of Central Tumors without Pyeloperfusion

PurposeTo assess the safety and technical success of percutaneous cryoablation (PCA) without pyeloperfusion in 94 patients with central renal tumors. Materials and MethodsA retrospective review of all central renal tumors treated by PCA without pyeloperfusion was performed. Central tumors were defined as those involving the renal sinus fat on preprocedural cross-sectional imaging. Patient demographics and baseline tumor characteristics were recorded. The details of the PCA procedure, primary and secondary technical success, rates of local recurrence, adverse events (AEs), cancer-specific survival (CSS), and overall survival (OS) were compiled. ResultsNinety-four patients (48 females [51%]; mean age, 68.2 years [range, 38–87 years]) with 94 central renal tumors were included. The mean maximal tumor diameter and mean RENAL nephrometry score were 37 mm (range, 15–67 mm) and 8 (range, 4–11), respectively. Primary technical success was achieved in 94% (n = 88) of procedures. Of the patients who did not achieve primary technical success, 3 underwent successful repeat PCA (secondary technical success, 97%; n = 91/94). The other 3 patients were surveilled for residual disease. Twenty-four patients (26%) required hydrodissection during PCA. Six patients (6%) experienced major AEs after PCA including hemorrhage requiring embolization (n = 3), hemorrhage requiring transfusions with admission (n = 2), and perinephric abscess necessitating drain placement (n = 1). Twenty-two patients (23%) experienced minor AEs. Nine patients (10%) experienced local recurrence during the follow-up period. OS was 94% (n = 88/94), whereas CSS was 98% (n = 92/94) during the study follow-up period (mean, 16 months [range, 1–102 months]). ConclusionsPCA of central renal tumors appears to be safe with high rates of technical success, even without the use of pyeloperfusion.

MP47-18 OUTCOMES OF PERCUTANEOUS RENAL CRYOABLATION IN A LARGE COHORT OVER 15 YEARS

You have accessJournal of UrologyCME1 Apr 2023MP47-18 OUTCOMES OF PERCUTANEOUS RENAL CRYOABLATION IN A LARGE COHORT OVER 15 YEARS Zachary A. Valley, Evan Allarie, Steven Lu, Richard Cormack, Michael Welsh, Bryan J. Donnelly, and Kamaljot S. Kaler Zachary A. ValleyZachary A. Valley More articles by this author , Evan AllarieEvan Allarie More articles by this author , Steven LuSteven Lu More articles by this author , Richard CormackRichard Cormack More articles by this author , Michael WelshMichael Welsh More articles by this author , Bryan J. DonnellyBryan J. Donnelly More articles by this author , and Kamaljot S. KalerKamaljot S. Kaler More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003293.18AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Historically, the standard of care for renal cell carcinoma (RCC) has been partial nephrectomy (PN) or radical nephrectomy (RN). Image-guided percutaneous cryoablation (PCA) of renal masses has emerged as a nephron-sparing, minimally invasive alternative. In this study, we aim to assess outcomes of percutaneous renal cryoablation at a single centre over 15 years. METHODS: Patients who underwent PCA of renal masses from 2006 to 2022 were included with no exclusions. All patients had cross-sectional imaging prior to the procedure and most underwent biopsy at the time of procedure. Cryoprobe placement and ice-ball formation was monitored via computed tomography (CT) imaging during the procedure. Data were collected via electronic medical record review, as well as pre-, intra-, and post-procedure imaging review. Data included demographics, tumor characteristics, pathology, local recurrence and metastatic disease rates, complications, pre- and post-procedure renal function and blood counts, co-morbidities, and mortality rate of patients in follow-up. RESULTS: This study included 598 patients in the analysis with a median age of 65.1 years and median follow-up of 39 months (Table 1). The average size of tumor was 2.7 cm. Overall local recurrence rate was 4.8% including surgically resected and hereditary RCC. Average nephrometry score was 6.1. Median time to local recurrence was 2.0 years. Five percent of patients made up 52% of the recurrences. Overall survival rate was 82.3% at time of analysis. Cancer-specific survival overall was 97.3%. Average length of time to discharge was 28.2 hours. The Clavien-Dindo 3+ complication rate was 2.3%. Overall metastatic rate was 1.8% and 0.7% in patients with no recurrence. CONCLUSIONS: PCA outcomes in this large cohort with no exclusions and long-term follow-up revealed an overall low recurrence rate, low complication rate, and an acceptable metastatic rate. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e651 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Zachary A. Valley More articles by this author Evan Allarie More articles by this author Steven Lu More articles by this author Richard Cormack More articles by this author Michael Welsh More articles by this author Bryan J. Donnelly More articles by this author Kamaljot S. Kaler More articles by this author Expand All Advertisement PDF downloadLoading ...

Feasibility of Computed Tomography-guided Percutaneous Renal Cryoablation Under Local Anesthesia: A Single Center Experience in Taiwan.

To survey the safety and efficacy of percutaneous cryoablation for renal tumors under local anesthesia and pain control by using the -40°C lethal isotherm of the ice ball to cover the tumor margin as well as the coaxial cryoablation technique. All procedures were performed between February 2014 and November 2021 with computed tomography (CT) guidance. All tumors were ablated by following the aforementioned plan, according to which tumor margins were covered by the -40°C lethal isotherm. Hydrodissection and coaxial cryoablation were performed in some cases to avoid organ injury and massive bleeding. 2% xylocaine was used for local anesthesia and 50 mg of pethidine (meperidine) was injected intramuscularly for pain control and sedation. The complications were evaluated and the Kaplan-Meier method was used to estimate local recurrence-free survival (LRFS). Sixty-five tumors [49 renal cell carcinomas (RCC) and 16 angiomyolipomas] were ablated in 55 patients (median Charlson Comorbidity Index=5.0). Local recurrence occurred in three of the 49 RCC cases. Two received a second cryoablation. LRFS at three and five years were both 91%. LRFS at three and five years reached 100% in tumors <3 cm. A large tumor (≥3 cm) was observed in the recurrence group. Hemorrhage was the most common complication (76.9%). Two patients who needed blood transfusion did not receive coaxial cryoablation. Three (4.6%) major complications (Clavien-Dindo grade ≥3) occurred. By using -40°C as the pre-plan tumor coverage, with the aid of coaxial cryoablation and multiplanar reconstruction method, CT-guided percutaneous renal cryoablation under local anesthesia is a safe and effective procedure in patients with many comorbidities.

External Validation of the Renal Ablation-Specific (MC)2 Risk Scoring System in Predicting Complications from Percutaneous Renal Cryoablation

The (MC)2 score is a renal ablation-specific risk scoring system to predict major complications from percutaneous renal cryoablation (PRCA). However, it is untested in an external population of patients. The purpose of this study is to validate the ability of the (MC)2 score to predict major complications after PRCA in an external population. Retrospective review of patients who underwent PRCA from 2004 to 2019. Patient demographics, medical histories, and tumor characteristics were collected. The (MC)2 score was calculated and patients were assigned to low risk (< 5), moderate risk (5-8) and high-risk (> 8) groups. Complications were recorded. Major complications were classified according to CIRSE guidelines. Two hundred and one patients [M = 116; F = 85; median age = 65 (range 27-90)] met inclusion criteria. Eleven patients (5.5%) developed major complications and 50 patients (24.9%) developed minor complications. Of patients with major complications, mean tumor diameter was 39mm (± 10.4), seven patients (63.6%) had a central tumor, four patients (36.4%) had complicated diabetes, and one patient (9.1%) had a prior MI. Major complication rates were 2.1%, 14%, and 14.3% in the (MC)2 low risk, moderate risk, and high risk groups, respectively. The mean (MC)2 score for patients with major complications [6.2 (± 2.4)] was higher than the mean score for patients with minor complications [4.7 (± 2.4) (p = 0.07)] and no complications [3.9 (± 1.9) (p < 0.01)]. The area under the ROC curve to predict major complications was 0.78. The (MC)2 risk scoring system appropriately identifies patients at risk for major complications from PRCA in this external patient population.

Percutaneous Renal Cryoablation for Small Renal Masses: The Price is Right.

Percutaneous Renal Cryoablation for Small Renal Masses: The Price is Right.

Long-term renal function outcomes after renal cryoablation complicated by major hemorrhage requiring selective transarterial embolization.

To determine long-term renal function outcomes after renal cryoablation complicated by major hemorrhage requiring transarterial embolization compared to patients who underwent uncomplicated renal cryoablation without major hemorrhage. Utilizing a matched cohort study design, retrospective review identified 23 patients who underwent percutaneous image-guided renal cryoablation complicated by major hemorrhage requiring ipsilateral transarterial embolization (TAE group) and a control group of 23 patients who underwent uncomplicated renal cryoablation matched 1:1 by age, gender and RENAL Nephrometry score at a single institution from 1/1/2005 to 12/31/2019. Primary outcome parameters included change in creatinine (mg/dl) and estimated glomerular filtration rate (ml/min/1.73 m2; eGFR) from baseline and were compared between TAE and control group using a paired t-test. There was a significantly higher proportion of patients on pre-ablation anticoagulation in the TAE v. control group (30% v. 4%; p = 0.047), but all patients were off anticoagulation and with normal coagulation parameters at the time of cryoablation. Otherwise there were no significant differences in clinical, renal tumor, Charlson co-morbidity index, baseline renal function or cryoablation parameters between the TAE and control group. In the post-ablation period, there was trend toward greater increase in creatinine from baseline to worst post-ablation creatinine in the TAE v. the control group (+ 0.5 ± 0.7mg/dl v. 0.2 ± 0.1mg/dl; p = 0.056). However, at a mean follow-up of 42.7 ± 35.7months, there was no significant difference between the TAE and control group in creatinine (p = 0.68), eGFR (p = 0.60) or change from baseline in creatinine (p = 0.28), eGFR (p = 0.80) or CKD stage (p = 0.74). No patient required initiation of hemodialysis. Selective transarterial embolization for post-renal cryoablation hemorrhage does not significantly affect long-term renal function compared to cryoablation alone. Pre-ablation anticoagulation despite normal coagulation at time of ablation may be a risk factor for post-ablation hemorrhage, and warrants further evaluation when considering pre-ablation embolization.

Percutaneous CT-Guided Renal Cryoablation: Technical Aspects, Safety, and Long-Term Oncological Outcomes in a Single Center.

Background and objectives: Cryoablation is emerging as a safe and effective therapeutic option for treating renal cell carcinoma. This study analyzed the safety and long-term oncological outcomes of cryoablation in our center. Materials and methods: Patients who underwent computed tomography (CT)-guided percutaneous cryoablation between February 2011 and June 2020 for one or more clinically localized renal tumors were identified. Technical success and treatment efficacy were assessed. Post-procedural complications were classified according to the Clavien-Dindo system. Recurrence–free survival was determined for biopsy-proven malignant renal tumors. Results: A total of 174 renal tumors, 78 of which were biopsy-proven malignant carcinomas, were treated in 138 patients (97 males and 41 females, mean age: 73 years, range: 43–89 years). Mean tumor size was 2.25 cm and 54.6% of the lesions required a complex approach. Technical success was achieved in 171 out of 174 tumors (98.3%). Primary treatment efficacy was 95.3% and increased to 98.2% when retreats were taken into account. The overall complication rate was 29.8%. No complications of Clavien-Dindo grade III or more were encountered. Median follow-up was 21.92 months (range: 0.02–99.87). Recurrence-free survival was 100% at 1 year, 95.3% (95% CI: 82.1%–98.8%) at 3 years, and 88.6% (95% CI: 71.8%–95.7%) at 5 years. Conclusions: Cryoablation is a safe and effective technique for the treatment of small renal lesions, with no major complications when performed by expert interventional radiologists. The multidisciplinary discussion is essential, especially considering the high number of histologically undetermined lesions. Our long-term oncological outcomes are encouraging and in line with the literature.

Safety and effectiveness of percutaneous renal cryoablation with conscious sedation

ABSTRACT Objective To investigate complications and treatment failure rates of percutaneous renal cryoablation (PRC) for small renal masses under local anaesthesia and conscious sedation (LACS), to assess the safety and effectiveness of this approach, as PRC is typically performed under general anaesthesia (GA). Patients and methods We retrospectively reviewed PRC under LACS from 2003 to 2017. We analysed perioperative parameters between patients who successfully underwent PRC under LACS and patients with post-procedural complications or treatment failure (renal mass enhancement after successful intraoperative tumour ablation). Two-sided non-parametric and Fisher’s exact tests were performed to compare uncomplicated or disease-free PRC with the complication or treatment failure group, respectively. Results A total of 100 PRCs under LACS were performed during the study period. Of these patients, six patients had at least one postoperative complication (6%), and treatment failure was diagnosed in nine patients (9%) after PRC [mean (SD) follow-up of 42.7 (26.6) months]. The procedural failure rate was 1%. No ablations were converted to GA. The mean tumour size was smaller in patients who had no complications during PRC compared to those who did, at a mean (SD) of 2.2 (0.6) cm vs 3.0 (1.0) cm (P = 0.039). The use of more intraoperative probes during the PRC was also associated with complications, at a mean (SD) 3.0 (1.4) vs 1.8 (0.8) (P = 0.021). Conclusions PRC under LACS is an effective and safe procedural approach for managing small renal masses with low complication, treatment failure, and procedural failure rates. Larger renal masses and intraoperative use of multiple probes is associated with an increased risk of PRC complications. Abbreviations BMI: body mass index; CCI: Charlson Comorbidity Index; GA: general anaesthesia; LACS: local anaesthesia and conscious sedation; PRC: percutaneous renal cryoablation; R.E.N.A.L.: Radius, Exophytic/Endophytic, Nearness, Anterior/Posterior, Location

Post-ablation syndrome after percutaneous cryoablation of small renal tumors: A prospective study of incidence, severity, duration, and effect on lifestyle

PurposeTo prospectively investigate the incidence, severity, duration, and effect on lifestyle of post-ablation syndrome (PAS) after percutaneous renal cryoablation. Materials and MethodsWe enrolled 39 patients (27 male and 12 female; mean age, 62 years) who underwent 40 CT-guided cryoablation sessions for pathologically proven renal cancer (mean size, 20 mm) between December 2015 and December 2017. Four symptoms attributable to PAS, i.e., fever, nausea, vomiting, malaise, and the synergistic effect of these symptoms on lifestyle by 21 days after ablation were evaluated using a questionnaire. Symptoms were graded according to the common toxicity criteria of adverse events. ResultsThe incidences of fever, nausea, vomiting, and malaise were 100% (40/40), 20% (8/40), 20% (8/40), and 63% (25/40), respectively. Most (78/81, 96%) symptoms had begun by day 2. The highest grade of fever per session was 0 (defined as ≥37.0 °C and <38.0 °C) (n = 24), 1 (n = 15), or 2 (n = 1); that of nausea was 2 (n = 8); that of vomiting was 1 (n = 7) or 3 (n = 1); and that of malaise was 1 (n = 14) or 2 (n = 11). Most (76/81, 94%) symptoms had resolved by day 8. The average values for the maximum scores of interference with general activity and work were 3.6 and 1.1, respectively. ConclusionAll symptoms were generally early-onset and self-limiting, with minimal impact on lifestyle and resolution by day 8. The clinical course and impact of PAS should be acknowledged by practitioners who manage patients undergoing renal cryoablation.

Safety of percutaneous renal cryoablation: an international multicentre experience from the EuRECA retrospective percutaneous database.

To investigate the safety profile of percutaneous cryoablation of renal tumours < 7cm, utilising data extracted from an international multicentre registry. A retrospective review of all immediate and delayed complications from a multicentre database was performed and was categorised according to the Clavien-Dindo classification. Statistical analysis was performed for both overall complications (all Clavien-Dindo) and major complications (Clavien-Dindo 3 to 5). The following criteria were identified as potential predictive factors for complications: centre number, modality of image guidance, tumour size (≤ 4cm vs. > 4cm), number of tumours treated in the same session (1 vs. > 1) and tumour histology. A total of 713 renal tumours underwent ablation in 647 individual sessions. In 596 of the cases, one tumour was treated; in the remaining 51 cases, several tumours were treated per session. Mean lesion size was 2.8cm. Fifty-four complications (Clavien-Dindo 1 to 5) occurred as a result of the 647 procedures, corresponding to an overall complication rate of 8.3%. The most frequent complication was bleeding (3.2%), with 9 cases (1.4%) requiring subsequent treatment. The rate of major complication was 3.4%. The only statistically significant prognostic factor for a major complication was a tumour size > 4cm. Percutaneous renal cryoablation is associated with a low rate of complications. Tumours measuring more than 4cm are associated with a higher risk of major complications. • Percutaneous kidney cryoablation has a low rate of complications. • Bleeding is the most frequent complication. • A tumour size superior to 4cm is a predictive factor of major complication.

Re: A Comparison of Bleeding Complications in Patients Undergoing Percutaneous Renal Cryoablation Using Cryoprobes with and without Heat-Based Track Ablation

Re: A Comparison of Bleeding Complications in Patients Undergoing Percutaneous Renal Cryoablation Using Cryoprobes with and without Heat-Based Track Ablation

A Comparison of Bleeding Complications in Patients Undergoing Percutaneous Renal Cryoablation Using Cryoprobes with and without Heat-Based Track Ablation

PurposeTo determine if the use of heat-based track ablation with new-generation cryoprobes is associated with decreased renal cryoablation bleeding complications. Materials and MethodsEighty-nine patients who underwent percutaneous cryoablation for treatment of a solitary renal mass with the use of cryoprobes with track ablation (CwTA) from October 29, 2015, to May 18, 2017, were compared with a propensity score–matched control group of 178 patients who underwent treatment with the use of cryoprobes without track ablation (Cw/oTA) from January 5, 2012, to October 28, 2015. Bleeding complications were assessed with the use of the Clavien-Dindo classification system and compared between the matched patient groups by means of conditional logistic regression, both univariately and in a multivariate model to adjust for imbalanced covariates. Change in patient hemoglobin was evaluated as a secondary measure of periprocedural bleeding. ResultsSeven of the 89 patients (7.9%) who underwent percutaneous renal cryoablation with the use of CwTA developed major (grade ≥3) bleeding complications, versus 13 of the 178 patients (7.3%) treated with the use of Cw/oTA. Conditional logistic regression analysis adjusted for potential confounders showed that major, minor, and overall bleeding complications were not associated with the type of cryoprobes used for treatment (P values .727, .370, and .733, respectively). There was also no significant difference in postprocedural change in hemoglobin for patients treated with the use of CwTA compared with Cw/oTA (P = .909). Furthermore, total duration of track ablation in patients with bleeding complications (mean 169 seconds, SD 68, range 60–240) was not significantly different than in patients without bleeding complications (mean 171 seconds, SD 86, range 30–360; P = .940). ConclusionsThe use of cryoprobes with heat-based track ablation did not decrease the incidence of bleeding complications after renal cryoablation compared with procedures performed without track ablation.

Efficacy of antegrade and retrograde warm saline pyeloperfusion during renal cryoablation for ureteral preservation.

Cryoablation of renal tumors adjacent to the ureter or pelvicalyceal system carries risks for thermal injury of the collecting system. Although cold antegrade perfusion has been described for radiofrequency ablation, warm saline perfusion for renal cryoablation has not been well-characterized. The purpose of this study was to determine the safety and feasibility of antegrade and retrograde warm saline perfusions during percutaneous renal cryoablation. A retrospective review was performed on 136 patients treated with percutaneous renal cryoablation at a single academic institution between 2009 and 2015. Six patients undergoing antegrade (n=3) or retrograde (n=3) warm saline perfusion for protection of the collecting system were identified. Warm saline was perfused through a 4 French nephrostomy tube in the antegrade technique and through a 6 French end-hole catheter in the retrograde technique. Outcome measures were tumor recurrence rates, success of urothelial preservation, hospital stay, blood loss and procedural time. Four tumors were in the lower pole and two tumors in the middle pole. The mean distance from tumor to ureter was 6.8 mm (0.8-11.5 mm) and no patient developed ureteral stricture. There was no tumor recurrence at a median follow-up of 37.3 months (7-65). The median procedural time was 3 hours and 13 minutes. One patient in each group developed minor complications (Clavien I and II) and there were no major complications. This study demonstrates the feasibility of antegrade and retrograde warm saline perfusion for ureteral preservation during cryoablation, without compromising oncologic outcomes.

Image-guided percutaneous renal cryoablation: Five years experience, results and follow-up

ObjectivesTo describe the experience of our institution in image-guided renal nodules percutaneous cryoablation, evaluating demographic and technical aspects as well as efficacy, safety and follow up. Materials and methodsRetrospective study approved by our institutional review board. Seventy-one renal tumors evaluated in 60 patients treated with image guided percutaneous renal cryoablation from January 2009 to December 2015. No patient was excluded from study, even those who were lost on follow up. All the procedures were guided both by ultrasound and tomography. An argon and helium based cryoablation machine was used for all treatments. Hydrodissection was performed when the bowel or ureters were within 1 cm (iodinated contrast media in dextrose solution). Complications were assessed by the terminology criteria of the National Institutes of Health (NIH). Patients were monitored and evaluated by ultrasound, tomography, MRI and/or PET-CT. ResultsIn most procedures (91.9%) only one nodule was treated. Nodules had a median size of 1.6 cm. Most nodules (61,9%) were exophytic. Hydrodissection and retrograde warm pyeloperfusion were performed in most procedures. Among all variables evaluated in univariate analysis, nearness of nodule to collecting system and anterior/posterior location were significantly associated with PRCA complications. No other factor evaluated was significantly associated with complications. ConclusionPRCA is solid alternative to traditional surgical therapies for treatment of small renal tumors in wide subset of patients. Medium term evidence shows excellent long-term oncological results, similar to nephrectomy, with minimal risk of major complications.

Long-term outcomes after percutaneous renal cryoablation performed with adjunctive techniques

ObjectiveTo review the technical success of image-guided percutaneous cryoablation of renal masses in difficult anatomic locations using adjunctive techniques to displace critical structures away from the ablation zone, while also reporting longer-term outcomes within this patient population. MethodsAn IRB approved, retrospective analysis of 92 renal masses treated with percutaneous cryoablation revealed 15 cases utilizing adjunctive techniques. Tumor size and distance to adjacent organ before and after adjunctive technique and long-term outcomes were evaluated. ResultsThe adjunctive techniques used were hydrodissection (n=15) and angioplasty balloon interposition (n=1). Before and after adjunctive technique, median tumor proximity to closest organ was 4mm and 26mm, respectively. All cases had appropriate ablation zones and protection of adjacent critical structures. There is no evidence of recurrence or complication on follow-up (median 51months). ConclusionsAdjunctive techniques to ablate renal masses in difficult locations provide technical success, safety, and favorable long-term outcomes.

Percutaneous Cryoablation of Renal Tumors: Is It Time for a New Paradigm Shift?

PurposeTo retrospectively assess long-term outcomes of percutaneous renal cryoablation, including factors affecting complications and local recurrence rates. Materials and MethodsA total of 357 computed tomographic (CT) fluoroscopy–guided percutaneous cryoablation procedures were performed for 382 masses in 302 outpatients; 347 were biopsy-proven renal-cell carcinoma (RCC) or Bosniak category > III masses (n = 28). Benign pathologic conditions (n = 18) or metastatic non-RCC disease (n = 17) were included to analyze procedural complication rate, but recurrence rates, tumor staging, and nephrometry score were limited to RCCs. The average tumor diameter was 2.9 cm (range, 1–10.3 cm), and median nephrometry score for RCC was 8 (mean, 7.4). Protection of adjacent vital structures was performed in 34% of procedures (n = 121), and ureteral stent placement was performed for 9.2% (n = 33). All major complications were graded per surgical Clavien–Dindo criteria. ResultsThe average CT-visible cryoablation zone diameter was 5 cm (range, 2.5–10.5 cm). Grade ≥ 3 complications occurred in 2.8% of procedures (n = 10), and appeared related to only high nephrometry scores (P = .0086) and larger tumors (P = .0034). No significant changes in renal function before and after the procedure were noted (P = .18). At a mean follow-up of 31.8 months, the local tumor recurrence rate was 3.2% (11 of 347) for RCC, and no significant difference was noted between tumors larger or smaller than 3 cm (P = .15). The difference reached significance only among the small number of stage ≥ T2 RCC tumors (P = .0039). ConclusionsLong-term follow-up of percutaneous renal cryoablation demonstrates low recurrence rates with preserved renal function, even for patients with high nephrometry scores and body mass index, assuming thorough cytotoxic technique and protection measures.

Changes in Perioperative Systolic Blood Pressure in Percutaneous Renal Mass Cryoablation.

To analyze changes in systolic blood pressure (SBP) in the perioperative period of percutaneous renal mass cryoablation and risk factors. This retrospective study included 54 patients who underwent percutaneous renal cryoablation. SBP before ablation (pre-Tx), during ablation (intra-Tx), immediately after ablation (post-Tx), and before discharge (discharge) were measured using a BP cuff. The highest SBP during cryoablation was regarded as SBP at intra-Tx. Antihypertensive agents were administrated when SBP was 160mmHg or greater during cryoablation. Relationship between SBP at pre-Tx, pain degree, tumor size, cryoprobe number, or endophytic extension of the radiographic ice-ball, and SBP elevation or administration of antihypertensive agents was investigated. Mean SBP elevation from pre-Tx to intra-Tx was 22.9±18.0mmHg (range -6-78mmHg). SBP of intra-Tx was significantly higher than that of the other periods (p<.001), while SBP of post-Tx or discharge was similar with that of pre-Tx (p>.05). Tumor size (r=.324; p=.016), cryoprobe number (r=.300; p=.027), and endophytic extension (r=.348; p=.009) were correlated with SBP elevation, while SBP at pre-Tx or pain degree were not (p>.05). Antihypertensive agents were administrated for 24 patients (44.4%). In multivariate analysis, SBP at pre-Tx and endophytic ablation was associated with administration of antihypertensive agents during cryoablation (p<.05). SBP elevation may occur during percutaneous renal mass cryoablation, but be improved before discharge. Endophytic extension of the radiographic ice-ball may be associated with significant BP elevation during ablation.

Estimated glomerular filtration rate on postoperative day 1 is associated with renal functional outcome after percutaneous renal cryoablation for renal tumors.

Estimated glomerular filtration rate on postoperative day 1 is associated with renal functional outcome after percutaneous renal cryoablation for renal tumors.

Analysis of the RENAL and mRENAL Scores and the Relative Importance of Their Components in the Prediction of Complications and Local Progression after Percutaneous Renal Cryoablation

PurposeTo determine if modified RENAL (mRENAL) score and its individual components have superior predictive value relative to the RENAL nephrometry score in prediction of complications and recurrence after percutaneous renal cryoablation. Materials and MethodsPrimary masses treated with CT–guided percutaneous renal cryoablation between June 2007 and May 2016 were retrospectively reviewed. RENAL and mRENAL scores were used to stratify masses into low, medium, and high complexity tertiles. Complications were characterized by SIR criteria. Predictors of complications and local progression were analyzed using multivariate logistic regression and Kaplan-Meier analysis. ResultsThere were 95 renal cryoablation procedures in 86 patients. Of ablations, 89 had at least 1 follow-up imaging study, with median follow-up of 29 months. There were 11 (12.4%) complications, including 5 (6.5%) major complications. Mass complexity, as measured by mRENAL complexity tertile, was associated with increased risk of complications on multivariate analysis (P = .045). Endophytic location was the only individual ordinal component of the RENAL and mRENAL scores associated with complications (P = .021). Local progression occurred in 7 (8.3%) masses. Complexity as measured by either scoring system was not associated with local progression. Only diameter > 3 cm was associated with increased risk of local progression (hazard ratio = 9.9, 95% confidence interval = 2.1–45, P = .003). ConclusionsmRENAL score was predictive of complications and tumor size was predictive of recurrence. Use of mRENAL score for complications and tumor size for recurrence should allow for simpler risk stratification and more accurate patient counseling.