Cryoablation For Renal Cell Carcinoma Research Articles

Effect of iodized oil embolization on temperature change during cryoablation for renal cell carcinoma

Introduction We aimed to evaluate the effect of transcatheter arterial embolization (TAE) with iodized oil (Lipiodol) on temperature change during cryoablation (CA) for renal cell carcinoma (RCC). Material and methods We retrospectively reviewed patients receiving CA for RCC from February 2020 to July 2021, including those who received Lipiodol TAE prior to CA (TAE group) and those who underwent only CA with comparable clinical and tumor characteristics (non-TAE group). Clinical data and tumor characteristics of both groups were recorded. The temperature readings of each cryoprobe at every 15 s and ‘time to −100 °C’ were compared between the groups. Results A total of 17 patients with 18 RCCs were recruited (seven in the TAE group and 11 in the non-TAE group). The ‘time to −100 °C’ was significantly longer in the TAE group than in the non-TAE group (64.5 ± 24.3 s vs. 48.8 ± 9.7 s, p = 0.018). Positive correlation between ‘time to −100 °C’ and tumor maximal diameter, RENAL nephrometry and PADUA score were observed in the non-TAE group, while no corresponding correlation was found in the TAE group. Conclusions Pre-embolization with iodized oil influences the temporal temperature changes during cryoablation by disrupting the positive correlation between the time to reach the target temperature and tumor characteristics.

Percutaneous cryoablation of renal cell carcinomas in patients with Von Hippel-Lindau disease: Functional and oncological outcomes.

Percutaneous cryoablation of renal cell carcinomas in patients with Von Hippel-Lindau disease: Functional and oncological outcomes.

Oncological and Peri-Operative Outcomes of Percutaneous Cryoablation of Renal Cell Carcinoma for Patients with Hereditary RCC Diseases-An Analysis of European Multi-Centre Prospective EuRECA Registry.

This study aims to evaluate the safety, efficacy, and renal function preservation of percutaneous cryoablation (PCA) for small renal masses (SRMs) in inherited RCC syndromes. Patients with inherited T1N0M0 RCCs (<7 cm) undergoing PCA from 2015 to 2021 were identified from the European Registry for Renal Cryoablation (EuRECA). The primary outcome was local recurrence-free survival (LRFS). The secondary outcomes included technical success, peri-operative outcomes, and other oncological outcomes estimated using the Kaplan-Meier method. Simple proportions, chi-squared tests, and t-tests were used to analyse the peri-operative outcomes. A total of 68 sessions of PCA were performed in 53 patients with RCC and 85 tumours were followed-up for a mean duration of 30.4 months (SD ± 22.0). The overall technical success rate was 99%. The major post-operative complication rate was 1.7%. In total, 7.4% (2/27) of patients had >25% reduction in renal function. All oncological events were observed in VHL patients. Estimated 5-year LRFS, metastasis-free survival, cancer-specific survival, and overall survival were 96.0% (95% CI 75-99%), 96.4% (95% CI 77-99%), 90.9% (95% CI 51-99%), and 90.9% (95% CI 51-99%), respectively. PCA of RCCs for patients with hereditary RCC SRMs appears to be safe, offers low complication rates, preserves renal function, and achieves good oncological outcomes.

Renal cryoablation combined with prior transcatheter arterial embolization in non-dialysis patients with stage 4 or 5 chronic kidney disease: a retrospective study

PurposeTo retrospectively evaluate cryoablation combined with prior transcatheter arterial embolization (TAE) for renal cell carcinoma (RCC) in non-dialysis patients with stage 4 or 5 chronic kidney disease (CKD).Materials and methodsPatients with stage 4 or 5 CKD undergoing TAE and cryoablation for RCC between May 2012 and October 2021 were included. TAE was selectively performed using iodized oil with absolute ethanol or gelatin sponge 1–14 days before cryoablation. Local efficacy, safety, and changes in renal function were evaluated.ResultsNine patients (seven men and two women; median age, 64 years; range 52–88 years) with nine RCCs (mean diameter, 3.0 ± 1.0 cm; range 1.7–4.7 cm) were included. The mean pre-treatment estimated glomerular filtration rate (eGFR) was 24.2 ± 5.6 ml/min/1.73 m2 (range 10.4–29.2 ml/min/1.73 m2). The mean amount of contrast medium used in TAE was 58 ± 29 ml (range 40–128 ml). Except in one patient (grade 3 pyelonephritis), no grade ≥ 3 complications occurred. During the follow-up period (median, 18 months; range 7–54 months), no local tumor progression occurred. In two patients with pre-treatment eGFR of < 20 ml/min/1.73 m2, hemodialysis was initiated at 3 and 19 months after cryoablation. At their last follow-up, the remaining seven patients showed a decrease of 6.2 ± 5.3 ml/min/1.73 m2 (range 0.7–17.2 ml/min/1.73 m2) in their eGFR.ConclusionCryoablation combined with TAE for RCC in non-dialysis patients with stage 4 or 5 CKD was effective and safe, with an acceptable impact on renal function.

Oncological and peri-operative outcomes of percutaneous cryoablation of renal cell carcinoma for patients with hereditary RCC diseases - An analysis of European multi-centre prospective EuRECA registry

Oncological and peri-operative outcomes of percutaneous cryoablation of renal cell carcinoma for patients with hereditary RCC diseases - An analysis of European multi-centre prospective EuRECA registry

Ablation zone considerations in cryoablation of RCC: accuracy of manufacturer provided model and change from first to second freeze cycle

PurposeTo determine the accuracy of manufacturer models and difference in ice ball dimensions from the first to second freeze cycles during cryoablation of renal cell carcinoma (RCC). MethodsAll patients who underwent cryoablation for RCC and had either a uniform type of needle placed in a pattern consistent with manufacturer provided data (n = 48) or computed tomography performed during the first and second freeze cycles (n = 28) were retrospectively reviewed. Ice ball measurements were made in relationship to the cryoablation probes. Factors which may affect the manufacturer prediction or change in the size of the ice ball from first to second freeze cycles were evaluated. ResultsThe visualized ice ball was significantly smaller than predicted in the long axis (LA) (Visualized: 29 mm ± 8; Predicted: 54 mm ± 7; p < 0.001), perpendicular transverse (PTR) (Visualized: 31 mm ± 7; Predicted: 52 mm ± 6; p < 0.001) and perpendicular craniocaudal (PCC) (Visualized: 30 mm ± 8; Predicted: 50 mm ± 7; p < 0.001). Furthermore, in the LA, PTR and PCC directions the achieved ice ball size was significantly closer to the predicted size as the total number of probes increased (p = 0.006, p = 0.048 and p = 0.023, respectively). The ice ball was significantly larger in the LA (3 mm (range: −7, 14 mm), p < 0.001), PTR (3 mm (range: −4, 11 mm), p < 0.001), and PCC (3 mm (range: 0, 26 mm), p < 0.001) dimensions on the second as compared to the first freeze cycle. ConclusionThe manufacturer provided model overestimates the size of the visualized Ice ball and Ice balls formed on the second freeze are significantly larger (median 3 mm) than those formed on the first freeze.

V69 - CT-guided percutaneous cryoablation for renal cell carcinoma

V69 - CT-guided percutaneous cryoablation for renal cell carcinoma

Percutaneous Cryoablation of Renal Tumors: Initial Indian Experience

Abstract Purpose The purpose of this study was to report short-term outcomes of cryoablation of early-stage renal tumors (T1a and T1b) at a tertiary hospital in India. Methods This was a retrospective study of consecutive patients who underwent cryoablation for renal cell carcinoma (RCC) from November 2018 to June 2020. Cryoablation was performed under combined ultrasound and computed tomography guidance using a helium-argon cryoablation system. Tumor number, size, location, nephrometry score, relationship of the tumor with pelvicalyceal system, and adjacent organs were tabulated, and technical and clinical success evaluated. Early and late recurrence and complications were also assessed. Results Eleven patients (median age: 62 years) with 11 tumors underwent cryoablation. The mean tumor size was 2.58 cm (range: 1.62–5.62 cm) with 10 lesions being T1a and one lesion T1b. Tissue sampling was done in 9/11 patients, 3 were papillary RCC and the rest, clear cell RCC. In two patients, the tumor was completely endophytic, three patients had partially endophytic tumors while 6 patients had exophytic lesions. The median nephrometry score was 6 (range: 4–11, Mode 4). Technical success was achieved in all patients. Complete response was achieved in 81% (9/11) of the patients at 1-month follow-up. Median follow-up period was 6 months. Two patients showed residual disease on follow-up imaging at 1 and 3 months, respectively. Conclusion Cryoablation is a promising, relatively new minimally invasive therapy for treating small renal tumors in India. It is safe, technically feasible, and shows excellent short-term efficacy.

Percutaneous Angiographically Assisted Cryoablation of Renal Cell Carcinoma under the Control of Flat-Detector Computed Tomography: Capabilities and Potential Advantages of the Technique

Purpose: Percutaneous cryoablation (PCA) of renal cell carcinoma (RCC) stage T1a (≤4 cm) generally performed using MDCT with intravenous contrast material administration. Most interventional radiology departments are not equipped MDCT scanners and this is holding back widespread adoption of this technique into practical medicine. Flat-detector computed tomography (FDCT) is included in the standard equipment of modern angiographic systems, which makes it possible to combine the technologies of computed tomography with various technologies of intra-arterial contrasting and endovascular treatment. The purpose of the study was to assess the possibilities and potential advantages of using intraarterial contrasting during FDCT-controlled PCA of RCC T1a.Material and methods: Since 2017 angiographically assisted PCA under the FDCT control performed in 14 patients with RCC T1a. The procedure was performed in the X-ray operating room on an Artis Zee Floor angiographic unit with FDCT function and iGuide Needle Guidance and 3D/3D Fusion technologies (Siemens, Germany) using the SeedNet Gold system and IceEDGE 13 G, IceRod 17 G or IceSphere 17 G cryoprobes (Galil Medical, USA). At all stages of the procedure, FDCT-arteriography of the kidney (FDCT-A) performed according to the original technique: injection into the renal artery 12 ml of non-ionic contrast materials at a rate of 1 ml/s and performing scanning 5 s after the start of contrast materials injection.Results: The primary technical efficiency of FDCT-controlled PCA of RCC T1a was 92.9 %, the secondary — 100 %. Complications of grade 3 according to the CIRSE classification were identified in three patients (21.4 %), complications of grade 4, 5 and 6 not observed. The use of arterial access and the FDCT-A execution at different stages of PCA had the following advantages: 1) high-quality visualization of the tumor with minimal consumption of contrast materials; 2) simple and accurate positioning of cryoprobes using the iGuide Needle Guidance program; 3) estimation of the future ablative margin by fusion FDCT data about tumor with FDCT data about ice ball; 4) reliable diagnosis of bleeding after removal of cryoprobes with the possibility of immediate performing of endovascular hemostasis.Conclusion: Percutaneous angiographically assisted cryoablation under the FDCT control is an affordable, safe and effective technology for the treatment of RCC T1a, which has a number of potential advantages compared to performing procedures using MDCT control. Further research is advisable to study of this PCA technique with its subsequent possible introduction into the routine practice in Interventional Radiology departments of multidisciplinary oncological hospitals.

CT evaluation of patent artery after percutaneous cryoablation of renal cell carcinoma

PurposeThe purpose of this retrospective study was to determine the incidence of persistent patent artery after percutaneous cryoablation of renal cell carcinoma (RCC) and the relationship between patent arteries one month after cryoablation and early tumor progression. Materials and methodsOne hundred and fifty-nine patients (112 men, 47 women; mean age, 63.6±14.6 [SD] years; age range: 21–91 years) who underwent percutaneous cryoablation for 186 RCCs (mean diameter, 1.9±0.6 [SD] cm; range: 0.7–4.0cm) were retrospectively included. After cryoablation, patients underwent contrast-enhanced computed tomography (CT) with ≤2-mm slice thickness within one week from cryoablation, and at one, three, and six months. The time course of patent artery in the ablated renal parenchyma after cryoablation was the primary endpoint. The relationships between patent arteries one month after cryoablation and treatment effectiveness, tumor vascularity, tumor enhancement one month after cryoablation, tumor subtype, and renal function changes were evaluated as secondary endpoints. ResultsCT showed patent arteries in the ablated renal parenchyma within one week in 166 RCCs (89.2%), at one month in 54 RCCs (29.0%), at three months in 8 RCCs (4.3%), and at six months in 2 RCCs (1.1%). The presence of patent artery one month after cryoablation was significantly associated with tumor enhancement at the same time point (P=0.015). There was no association between patent arteries one month after cryoablation and treatment effectiveness (P=0.693). ConclusionPatent arteries in the ablated renal parenchyma are commonly observed on CT examination after percutaneous cryoablation of RCC. However, they gradually disappear and do not require specific treatment.

Risk factors for abdominal wall pseudohernia after percutaneous cryoablation of renal cell carcinoma.

IntroductionPercutaneous cryoablation (PCA) is increasingly recognized as a feasible minimally invasive, nephron-sparing treatment for renal cell carcinomas, with comparable efficacy to nephrectomy. The development of abdominal wall pseudohernia (AWP) is a rare complication of PCA for renal masses, which can negatively impact patients’ quality of life.AimTo retrospectively evaluate the risk factors and prognosis for AWP after PCA and, based on these results, to discuss strategies to lower the risk of AWP associated with image-guided PCA for renal masses.Material and methodsWe retrospectively studied 117 PCAs performed for renal masses in 92 patients, between 2016 and 2019, at our hospital. We compared the following clinical characteristics (age, sex, body mass index, tumour diameter, RENAL nephrometry score, procedural details, transcatheter arterial embolization, dissection techniques, number of cryoneedles used, location of needles, and location of ice ball) between those who developed AWP and those who did not.ResultsOf the 117 PCAs (92 patients) included in our study group, AWP complications were observed in 6 (5.1%) procedures. Puncture through the erector spinae muscle (p < 0.01) and non-use of hydro- or pneumo-dissection (p = 0.01) were identified as risk factors for AWP.ConclusionsAlthough PCA is relatively safe to perform and the occurrence of an associated AWP is a rare and infrequent complication, the risk for AWP could be further decreased by avoiding punctures through the erector spinae muscle and using hydro- or pneumo-dissection.

Cryoablation for Secondary Renal Cell Carcinoma After Surgical Nephrectomy.

To retrospectively evaluate the clinical outcomes of cryoablation for secondary renal cell carcinoma for patients with a history of nephrectomy for initial renal cell carcinoma. Thirty patients with 40 renal tumors who had undergone a nephrectomy for initial renal cell carcinoma and cryoablation for renal cell carcinoma as a secondary treatment during the period from April 2014 to December 2018 at a single center institution were enrolled. The patients' overall survival, local control, relapse-free survival, change of renal function, and complications were evaluated. The clinical factors of relapse-free survival were also evaluated. The 5year overall survival rate was 94.5%, the 5year local control rate was 89.3%, and the 5year relapse-free survival rate (RFSR) was 56.3%. There was an average reduction in renal function of 8.5% after 1year, and > grade 3 complications occurred in only one case. The RFSR in the patients whose initial stage was T3 was 0%, significantly lower than the 70.4% RFSR in the patients whose initial stage was T1 or T2. Cryoablation for secondary renal cell carcinoma after nephrectomy was safe and provided good local control with preserved renal function. However, the indications for cryoablation should be carefully considered for patients with T3-stage initial renal cell carcinoma, because of the high risk of relapse. III.

Oncologic outcomes and safety of percutaneous cryoablation for biopsy-proven renal cell carcinoma up to 4cm in diameter: a prospective observational study.

Percutaneous cryoablation is widely used for the treatment of renal cell carcinoma. We prospectively evaluated the oncologic outcomes and safety of percutaneous cryoablation for the treatment of tumors ≤ 4cm in diameter. We included patients aged ≥ 20years, who had histologically proven renal cell carcinoma, tumor diameter ≤ 4cm, a performance status of ≤ 1, acceptable laboratory parameters, were inoperable or refused to undergo surgery, and had signed a written informed consent. The primary endpoint was the cause-specific survival rate. The secondary endpoints were overall and progression-free survival, and adverse event frequency and grade. All procedures were percutaneously performed under computed tomography fluoroscopy guidance. From October 2013 to October 2015, 33 patients (mean age: 68 ± 14years; sex: six women, 27 men) were enrolled. The mean tumor diameter was 2.1 ± 0.6 (range 1.0-3.4) cm. The median follow-up period was 60.1 (range 18.4-76.6) months. One patient died of non-renal cell carcinoma-related disease 46months after percutaneous cryoablation. The cause-specific and overall survival rates were 100% and 96.8% at 3years, and 100% and 96.8% at 5years, respectively. There was no local tumor progression or distant metastasis. The incidence of severe urological (urinary fistula and perinephric infection) and non-urological adverse events (increased creatine kinase and skin ulceration) was 6% each. Percutaneous cryoablation for renal cell carcinoma ≤ 4cm in diameter achieved good tumor control with a low complication frequency.

Combined Laparoscopic and CT Monitoring of the Ice-Ball Margin during Cryoablation for Renal Cell Carcinoma Associated with von Hippel-Lindau Disease: First Case.

We report a 47-year-old Japanese female with 10 previous treatments for multiple bilateral renal cell carcinoma (RCC) associated with von Hippel-Lindau disease. The 14-mm right lower pole renal tumor was in contact with the right ureter. Laparoscopic cryoablation was performed to protect the ureter wrapped with gauze. Computed tomography (CT) monitoring was used to confirm the precise ≥ 6 mm ice-ball margin. There was no local progression at 6-months post-surgery. The serum creatinine has been stable. This is apparently the first report of combined laparoscopic and CT monitoring of an ice-ball formation and its margin during cryoablation for RCC.

Safety and Oncologic Outcomes of Magnetic Resonance Imaging-Guided Cryoablation of Renal Cell Carcinoma: A 10-Year Single-Center Experience.

Magnetic resonance imaging guidance has been sporadically reported for renal tumor cryoablation (CA); therefore, clinical experience with this modality is still limited.The aim of this study is to retrospectively analyze our 10-year experience with renal tumor CA performed on a 1.5 T magnetic resonance imaging unit with the intent of reporting procedural safety and oncologic outcomes. We included 143 patients (102 men; 41 women; median age, 73 years; range, 34-91 years) with 149 tumors (median size, 2.6 cm; range, 0.6-6.0 cm), treated between 2009 and 2019. Patient, tumor, procedure, and follow-up data were collected and analyzed. The Kaplan-Meier method was used to estimate local recurrence-free (LRFS), metastasis-free (MFS), disease-free (DFS), cancer-specific, and overall (OS) survival. Univariate and multivariate models were used to identify factors associated with complications, LRFS, MFS, DFS, and OS. The overall complication rate was 10.7% (16/149 tumors), with 1 major (1/149 [0.7%]; 95% confidence interval, 0.0%-3.7%) hemorrhagic complication. Other minor complications (15/149 [10.1%]; 95% confidence interval, 0.6%-16.1%) did not include any cases of injury to nearby organs. There were no factors associated with complications.Five-year estimates of LRFS (primary/secondary), MFS, DFS, cancer-specific survival, and OS were 82.8%/91.5%, 91.1%, 75.1%, 98.2%, and 89.6%, respectively. Increasing tumor size (hazard radio [HR], 1.8; P = 0.02) and intraparenchymal tumor location (HR, 5.6; P < 0.01) were associated with lower LRFS; increasing patient's age (HR, 0.5; P = 0.01), high tumor grade (HR, 23.3; P < 0.01) and non-clear-cell/nonpapillary histology (HR, 20.1; P < 0.01) with metastatic disease; and high tumor grade (HR, 3.2; P = 0.04) with lower DFS. Magnetic resonance imaging-guided CA of renal tumors is associated with acceptable morbidity and high survival estimates at 5-year follow-up. Given the absence of complications resulting from injuries to nearby organs, further studies are required to evaluate whether the potential reduced incidence of these adverse events justifies large-scale implementation of this interventional modality.

Efficacy of arterial infusion of iodized oil on CT-guided cryoablation for renal cell carcinoma

Purpose To evaluate the effectiveness of the transarterial infusion of iodized oil and gelatin particles for marking before CT-guided percutaneous cryoablation (PCA) in patients with renal cell carcinoma (RCC). Material and methods This study included ten patients (seven men, three women; mean age 53 years) with 13 RCCs between July 2016 and September 2017. The transarterial infusion of iodized oil and gelatin particles was considered successful when iodized oil accumulated in the target area on CT. CT value of the tumor before and after marking was measured and two diagnostic radiologists evaluated the visualization scores by using a five-point scale (5 = excellent to 1 = invisible). Results Preoperative marking was successful in all 13 tumors; the median visualization score was 5 post-lipiodol marking and 4 at the time of PCA. The mean CT density was 597 ± 371 Hounsfield units (HU) just after marking and 437 ± 234 HU at the time of PCA. All 13 CT-guided PCA procedures were successful. There were no significant complications. During follow-up (median 11.5 ± 7.0 months) there were no local recurrences. Conclusion As the transarterial infusion of iodized oil and gelatin particles improved RCC visualization on CT, its delivery before CT-guided PCA may improve its safety and success rate in patients with RCC.

Cryoablation of renal cell carcinoma for patients with stage 4 or 5 non-dialysis chronic kidney disease.

To evaluate the safety and efficacy of cryoablation for renal cell carcinoma (RCC) in patients with stage 4 or 5 non-dialysis chronic kidney disease (CKD). This retrospective multicenter study included patients with maximum tumor diameter ≤4cm, estimated glomerular filtration rate (eGFR) <30ml/min/1.73m2, in whom cryoablation was performed percutaneously with curative intent between July 2011 and May 2016. Of 541 patients who underwent renal tumor cryoablation, 17 (3.1%; 4 women, 13 men; mean age 70.1±10.6years) with stage 4 or 5 non-dialysis CKD were included in this study. The pre-cryoablation eGFR was 22.5±6.3ml/min/1.73m2. The mean tumor diameter was 2.8±0.7cm. No Grade 3 or higher adverse events occurred post-cryoablation. The eGFR at each time point was significantly lower than that before treatment. One patient required hemodialysis initiation at 21months post-procedure. None of the patients showed residual RCC at their last follow-up. Cryoablation of RCC is safe in patients with stage 4 or 5 non-dialysis CKD and yields treatment results comparable to those in patients without CKD. This treatment could be completed without the early initiation of hemodialysis after the procedure.

Time-Dependent Effects of Cryoablation for Renal Tumor on Overall and Split Renal Function

PurposeTo evaluate the influence of percutaneous cryoablation for renal cell carcinoma on function of the affected kidney. Materials and MethodsBetween June 2016 and September 2017 at our institution, 12 inoperable patients underwent 15 cryoablation sessions for 17 small renal tumors. Of these, 9 patients who underwent 11 sessions of cryoablation were the focus of this study. For those patients, time-dependent changes in postoperative renal function were investigated by a retrospective review of clinical records. Evaluated were the estimated glomerular filtration rate (eGFR) and scintigraphy using 99m technetium-mercaptoacetyltriglycine (99mTc-MAG3) before and 1 week, 1–2 months, and more than 6 months after cryoablation. ResultsMean baseline eGFR was 76.88 ± 29.82 mL/min/1.73 m2 (mean ± standard deviation; range, 23.4–112.5). Mean eGFR 1 week, 1–2 months, and more than 6 months after cryoablation were 74.56 ± 26.68 mL/min/1.73 m2 (21.0–101.1), 69.5 ± 25.28 mL/min/1.73 m2 (24.1–105.6), and 75.08 ± 26.25 mL/min/1.73 m2 (29.0–107.3), respectively. Changes were statistically insignificant (P = .6044, P = .6699, and P = .9038, respectively). Regarding split renal function, the mean baseline contribution of the affected kidney determined by 99mTc-MAG3 was 47.27% ± 6.14 (38.8%–57.0%). Mean contributions of the affected kidney 1 week after, 1–2 months after, and more than 6 months after cryoablation were 44.40% ± 5.37 (38.3%–53.6%), 44.57% ± 6.52 (34.35%–55.0%), and 45.41% ± 7.77 (34.4%–56.5%), respectively. Differences from baseline were significant for the earliest 2 periods (P = .0473 and P = .0334, respectively) but not the later period (P = .2532). ConclusionsResults suggested that total renal function does not worsen after cryoablation; however, function of the affected kidney worsened after cryoablation but later partially recovered.

Percutaneous cryoablation for renal cell carcinoma using ultrasound-guided targeting and computed tomography-guided ice-ball monitoring: radiation dose and short-term outcomes.

Usefulness of ultrasound (US)-guided mass targeting and computed tomography (CT)-guided ice-ball monitoring in percutaneous cryoablation (PCA) for renal cell carcinoma (RCC) is still uncertain. To assess radiation dose and short-term outcomes of PCA for RCC using US-guided targeting and CT-guided ice-ball monitoring. Thirty-nine consecutive patients who underwent PCA for biopsy-proven RCC were included. Mass targeting was performed with US and ice-ball was monitored with CT guidance. Effective radiation dose of CT during PCA was recorded. Follow-up was conducted with contrast-enhanced CT or magnetic resonance imaging (MRI) (mean follow-up time = 10.1 ± 7.0 months). Local tumor progression was defined by the presence of focal enhancing areas at the ablation zone (CT, ≥ 20 HU; MRI, presence of focal enhancement on subtraction contrast-enhanced image). Technical success, major complication rate (e.g. Clavien-Dindo classification ≥ 3), and one-year local tumor progression-free survival (PFS) rate were analyzed. Mean effective radiation dose in association with PCA was 12.1 ± 4.5 mSv (range = 7.0-25.2 mSv). Technical success was achieved in 100%. Local tumor progression occurred in a single patient (2.6%, 1/39), and one-year local tumor PFS rate was 95.7%. No major complication was found. PCA using US-guided targeting and CT-guided ice-ball monitoring may allow acceptable local tumor control for RCC, as a radiation-reducing strategy.

Local anesthesia for ultrasound-guided percutaneous cryoablation of renal cell carcinoma

Background. There is a category of patients with renal masses, due to severe concomitant diseases, can not perform the operation or may be associated with a threat to life. In addition, many patients with small tumor sites are extremely concerned about their disease and are negative about the tactics of active observation and insist on treatment. These patients can be offered alternative methods of treatment of renal cell carcinoma (RCC), the leading of which is cryoablation.Objective: to evaluate the effectiveness and safety of percutaneous cryoablation of the kidney tumor under ultrasound control.Materials and methods. In the Urology Clinic of the I.M. Sechenov First Moscow State Medical University during the period from 2015 to 2017 performed 23 percutaneous cryoablation of RCC, 7 (men – 4, women – 3) of which were performed under local anesthesia. In 4 patients due to severe concomitant diseases, general anesthesia was associated with an extremely high risk. Three patients refused from dynamic observation and from traditional surgical treatment; preferred an alternative treatment in the form of a percutaneous cryoablation under local anesthesia. In 4 cases, the formations were located in the lower segment along the posterior surface of the kidney, in 3 – along the lateral surface in the middle segment. The size of the formations was not used 4 cm (T1a). The age of the patients was 62.3 years (51 to 83 years). Right-sided localization of the tumor was noted in 3 patients, left-sided – in 4. One patient had a single kidney.At the preoperative stage and 6 months after the operation, all patients underwent ultrasound with dopplerography, multislice computerized tomography with contrast, and computer 3D modeling, which helped to clearly assess the size of the tumor, clarify the prevalence of the tumor process and the spatial ratio of the internal surface of the tumor node to the elements of the bowl-and-pelvis system. In all the observations, the formations were located along the posterior or lateral surface of the kidney; in the lower or middle segment; without invasion of the sine. We used a 3rd generation cryomash machine SeedNet gold (Galil Medical), cryoprobes IceSeed and IceRod. Intraoperative, immediately before cryoablation, a tumor biopsy was performed, the presence of RCC in all patients was confirmed morphologically.Results. According to the ultrasound examination with echodopplerography at 6 months after the operation, the size of the tumor node’s formations decreased on average by 6–8 mm, while there was no blood flow in them. When multislice computerized tomography with 3D modeling was performed, the formation was reduced and the accumulation of the contrast preparation was completely absent or their accumulation gradient did not exceed 10 HU (initially it was about 200 HU). There were no intraoperative complications. In 1 observation, a postoperative hematoma measuring 7 × 3 cm was resolved conservatively and did not require surgical treatment.Conclusions. Percutaneous cryodestruction under local anesthesia using ultrasound guidance seems to be an effective and safe technique for treating patients with stage T1a RCC with localization in the posterior or lateral surface in the lower or middle segments without invasion of the renal sinus and surrounding tissues. It is planned to continue monitoring patients to assess the long-term effectiveness of cryoablation.