Magnetic-Resonance-Imaging-Guided Cryoablation for Solitary-Biopsy-Proven Renal Cell Carcinoma: A Tertiary Cancer Center Experience.

BACKGROUND: Our purpose is to evaluate the long-term oncologic efficacy and survival rates of MRI-guided cryoablation for patients with biopsy-proven cT1a renal cell carcinoma (RCC). MATERIALS AND METHODS: We retrospectively reviewed our renal ablation database between January 2007 and June 2021 and only included patients with solitary-biopsy-proven cT1a RCC (≤4 cm) who underwent MRI-guided cryoablation. We excluded patients with genetic syndromes, bilateral RCC, recurrent RCC or benign lesions, those without pathologically proven RCC lesions and patients who underwent radiofrequency ablation or CT-guided cryoablation. For each patient, we collected the following: age, sex, lesion size, right- or left-sided, pathology, ablation zone tumor recurrence, development of new tumor in the kidney other than ablation zone, development of metastatic disease, patient alive or not, date and cause of death. We used the Kaplan and Meier product limit estimator to estimate the survival outcomes. RESULTS: Twenty-nine patients (median age 70 years) met our inclusion criteria. Twenty-nine MRI-guided cryoablation procedures were performed for twenty-nine tumor lesions with a median size of 2.2 cm. A Clavien-Dindo grade III complication developed in one patient (3.4%). Clear cell RCC was the most reported histology (n = 19). The median follow up was 4.5 years. No tumor recurrence or metastatic disease developed in any of the patients. Two patients developed new renal lesions separate from the ablation zone. The 5- and 10-year OS were 72% and 55.6%, respectively. The 5- and 10-year DFS were 90.5% and the 5-year and 10-year LRFS, MFS and CSS were all 100%. CONCLUSIONS: MRI-guided cryoablation is a safe treatment with a low complication rate. Long-term follow-up data revealed long-standing oncologic control.

Comparison of Renal Damage Following Renal Artery Embolization with Three Different Embolic Mixtures in Swine.

Purpose: Renal artery embolization is a minimally invasive and effective procedure for renal ablation, a complete necrosis of the renal parenchyma. This study aims to compare the extent of renal damage in swine following renal artery embolization with ethanol and N-butyl-2-cyanoacrylate, commonly used as embolic materials in renal ablation. Material and Methods: Three different embolic mixtures were prepared for renal artery embolization in swine: 33% ethanol-Lipiodol mixture (ethanol:Lipiodol = 1:2; Group A), 67% ethanol-Lipiodol mixture (ethanol:Lipiodol = 2:1; Group B), and 10% N-butyl-2-cyanoacrylate-Lipiodol mixture (N-butyl-2-cyanoacrylate:Lipiodol = 1:9; Group C). Three swine were assigned to each group and underwent embolization of the unilateral renal artery. Renal arteriography was performed before, immediately after, and two days after renal artery embolization. After two days, the kidneys were removed to determine the macroscopic necrosis rate and for histologic examination. Dark tissue regions were considered necrotic. Results: The macroscopic necrosis rate of the kidneys was 50.3%±7.4%, 100%±0%, and 100%±0% in Groups A, B, and C, respectively. The necrosis rates were higher in Groups B and C than in Group A. Histologically, the renal tubules were damaged in the necrotic areas. In addition, the glomeruli were damaged in Groups A and B but were preserved in Group C. Conclusions: Sixty-seven percent ethanol-Lipiodol mixture and 10% N-butyl-2-cyanoacrylate-Lipiodol mixture are effective embolic materials in renal artery embolization for renal ablation in swine. Also, ethanol caused partial glomerular necrosis, whereas N-butyl-2-cyanoacrylate preserved the glomeruli. Therefore, ethanol should be used for renal ablation.

Tips and Tricks for Successful Percutaneous Cryoablation of Large Renal Cell Carcinomas.

Percutaneous cryoablation has proved to be safe and effective for the treatment of stage T1a renal cell carcinoma (RCC). Patients with larger-sized RCCs may not be good surgical candidates or may have tumors located in anatomically unfavorable locations, which makes partial nephrectomy more challenging. In this patient population, percutaneous cryoablation can be considered a treatment option, given its less invasive nature when compared to surgery. The ablation of larger-sized RCCs requires careful planning to ensure that the tumor volume is completely covered within the ablation zone, while minimizing the risks of non-target injury to the surrounding critical organs. In this article, we share our institutional experience in treating larger-sized RCCs (> 4 cm) using percutaneous cryoablation alone. We discuss strategies to maximize the volume of the ablation zone through the precise placement of the probes. We also shed light on different techniques to protect the surrounding structures during cryoablation.

Cone-Beam CT-Assisted Ablation of Renal Tumors: Preliminary Results.

INTRODUCTION: Renal ablation is a recognized treatment modality for small renal masses. Cone-beam CT (CBCT) has been recently used in interventional oncology as a promising new guidance device, but this technology still needs to be validated for renal ablations. We aimed to assess the technical success of CBCT applications in renal ablative treatments. MATERIALS AND METHODS: Between March 2016 and June 2018, 14 patients (mean age 69, range 54-83, 7F, 7M) underwent 21 renal ablations for histologically proven renal cell carcinoma (RCC). All treatments were performed with ultrasound (US) and CBCT guidance under general anesthesia in a dedicated angiography room setting. CBCT was mainly used to assess needle placement and to exclude complications at the end of the procedure. In two small lesions (< 1 cm), pre-acquired CBCT was co-registered with real-time US to obtain a US-CBCT fusion image guidance for tumor ablation. RESULTS: Whether used alone or in combination with other imaging modalities, CBCT was proven to be technically successful in all 21 procedures to guide or assist tumor ablation. A primary technical efficacy of thermal ablation was achieved in 19/21 ablations (90.1%) at 1 month. Mean procedure duration was 100.2 min (range 160-64). Mean length of hospital stay was 2 days (range 1-10 days). All patients are still under active surveillance for a mean follow-up of 14.5 months (range 4-26 months). CONCLUSIONS: CBCT for renal ablation guidance is a viable tool. Larger series are needed to compare it to MDCT.

Pneumodissection during Percutaneous Renal Ablation Resulting in Air Embolism: Percutaneous Management and a Review of the Literature.

Percutaneous renal ablation is a nephron-sparing approach for selected patients with renal cell carcinoma. Common complications include hemorrhage, injury to the urinary collecting system, and abscess formation. The purpose of this article is to present a case of vascular air embolism as a complication of pneumodissection performed during percutaneous ablation of renal cell carcinoma, discuss its successful percutaneous management, review common complications of renal ablation, and outline steps physicians can take to lessen these complications.

Cardioprotection Conferred by Sitagliptin Is Associated with Reduced Cardiac Angiotensin II/Angiotensin-(1-7) Balance in Experimental Chronic Kidney Disease.

Dipeptidyl peptidase IV (DPPIV) inhibitors are antidiabetic agents that exert renoprotective actions independently of glucose lowering. Cardiac dysfunction is one of the main outcomes of chronic kidney disease (CKD); however, the effects of DPPIV inhibition on cardiac impairment during CKD progression remain elusive. This study investigated whether DPPIV inhibition mitigates cardiac dysfunction and remodeling in rats with a 5/6 renal ablation and evaluated if these effects are associated with changes in the cardiac renin-angiotensin system (RAS). To this end, male Wistar rats underwent a 5/6 nephrectomy (Nx) or sham operation, followed by an 8-week treatment period with the DPPIV inhibitor sitagliptin (IDPPIV) or vehicle. Nx rats had lower glomerular filtration rate, overt albuminuria and higher blood pressure compared to sham rats, whereas CKD progression was attenuated in Nx + IDPPIV rats. Additionally, Nx rats exhibited cardiac hypertrophy and fibrosis, which were associated with higher cardiac DPPIV activity and expression. The sitagliptin treatment prevented cardiac fibrosis and mitigated cardiac hypertrophy. The isovolumic relaxation time (IRVT) was higher in Nx than in sham rats, which was suggestive of CKD-associated-diastolic dysfunction. Sitagliptin significantly attenuated the increase in IRVT. Levels of angiotensin II (Ang II) in the heart tissue from Nx rats were higher while those of angiotensin-(1-7) Ang-(1-7) were lower than that in sham rats. This cardiac hormonal imbalance was completely prevented by sitagliptin. Collectively, these results suggest that DPPIV inhibition may delay the onset of cardiovascular impairment in CKD. Furthermore, these findings strengthen the hypothesis that a crosstalk between DPPIV and the renin-angiotensin system plays a role in the pathophysiology of cardiorenal syndromes.

Interventional Oncology: Keeping Out of Trouble in Ablation Techniques.

Interventional radiologists provide an essential role in the therapy and management of cancer patients. Computed-tomography (CT) guided percutaneous procedures have enabled interventionalists to treat multiple solid organ malignancies with minimal risk, however, certain lesions may present challenges to physicians due to a difficult approach, or their close proximity to other vital structures. The following presents a brief summary of tips and tricks the interventionalist may use to provide their patients with safe and effective therapy.

Valoración de la variabilidad de la frecuencia cardiaca en pacientes con hipertensión arterial sistémica tratados mediante ablación renal por radiofrecuencia. Serie de casos / Assessment of the variability of the cardiac frequency in patients with systemic arterial hypertension treated through renal ablation by radio frequency. Series of cases

Resumen Introducción La hipertensión arterial sistémica refractaria es la presión arterial en el consultorio por encima de la meta apropiada a pesar del uso de tres o más antihipertensivos, uno de los cuales es un diurético; la denervación renal por ablación por radiofrecuencia es un tratamiento para este padecimiento, el cual es efectivo y seguro. Consideramos que la denervación disminuye el tono del sistema nervioso autónomo a nivel renal (eje renina angiotensina aldosterona), por lo que el resultado será la disminución de la presión arterial sin afectar la variabilidad de la frecuencia cardiaca. Objetivo Determinar si existe modificación en la variabilidad de la frecuencia cardiaca en pacientes con hipertensión arterial sistémica refractaria que son tratados mediante denervación renal por radiofrecuencia con catéter. Material y métodos Estudio observacional, descriptivo y analítico de pacientes con hipertensión arterial sistémica refractaria que fueron tratados mediante ablación renal por radiofrecuencia con catéter. Se midió la variabilidad de la frecuencia cardiaca en el dominio temporal y frecuencial, antes y dos meses después del procedimiento. El análisis estadístico de resultados se hizo con la prueba t de Student para muestras relacionadas. Resultados Fueron elegibles nueve pacientes, sólo se incluyeron seis pacientes con hipertensión arterial sistémica refractaria tratados mediante ablación renal por radiofrecuencia en el dominio temporal para la desviación estándar de los intervalos NN (SDNN), se observó un incremento estadísticamente no significativo (7 ms, p = 0.58). Conclusión En los seis pacientes con hipertensión arterial sistémica refractaria tratados mediante ablación renal por radiofrecuencia se observó, dos meses posteriores al procedimiento, que la variabilidad de la frecuencia cardiaca en el dominio temporal para la desviación estándar de los intervalos NN (SDNN) se incrementó 7 ms, siendo estadísticamente no significativo (p = 0.58).

Abstract Introduction Refractory systemic arterial hypertension is the blood pressure above the appropriate goal despite the use of three or more antihypertensive drugs, one of which is a diuretic; renal denervation by radiofrequency ablation, is a treatment for this condition, which is effective and safe. We consider that denervation decreases the tone of the autonomic nervous system at the renal level (renin angiotensin aldosterone axis), so that the result will be a decrease in blood pressure without affecting the variability of the heart rate. Objective To determine if there is a change in the variability of heart rate in patients with refractory systemic arterial hypertension who are treated by radiofrequency renal denervation with catheter. Material and methods Observational, descriptive and analytical study of patients with refractory systemic arterial hypertension who were treated by radiofrequency renal ablation with catheter. The variability of the heart rate in the temporal and frequency domain was measured before and two months after the procedure. The statistical analysis of results was by Student's t-test for related samples. Results Nine patients were eligible, only six patients with refractory systemic arterial hypertension treated by radiofrequency renal ablation were included, in the domain temporal domain for the standard deviation of the NN intervals (SDNN), a statistically non-significant increase was observed (7 ms, p = 0.58). Conclusion In the six patients with refractory systemic arterial hypertension treated by radiofrequency renal ablation, it was observed two months after the procedure, that the variability of the heart rate in the time domain for the standard deviation of the NN intervals (SDNN), it increased 7 ms, being statistically non-significant (p = 0.58).

Assessing the Effect of Weight-Based Protocol Modifications to Lower Dose for CT-Guided Hepatic and Renal Tumor Radiofrequency Ablations.

OBJECTIVE: This study assessed radiation dose after CT-guided percutaneous radiofrequency ablations (RFAs) of hepatic and renal tumors and the effect of weight-based CT protocol modification for lowering overall dose in these procedures. MATERIALS AND METHODS: CT-guided RFA for renal and hepatic ablations performed from January 1, 2009, through December 31, 2009, were retrospectively reviewed (90 men and 48 women; age, 42-81 years). The radiation dose was recorded during each of the following steps: planning, performing, and postprocedure. Weight-based protocol modification changes in tube voltage and tube current were then applied to renal and hepatic ablations performed subsequently (18 men and 11 women; age, 48-82 years). Image quality, needle localization, lesion detection, ability to detect complications, and overall operator satisfaction were noted for each case (score, 1-5). Dose reduction after modification was then calculated. RESULTS: Retrospective analysis found a mean (± SD) overall CT dose index (CTDI) for CT-guided RFA to be 16.5 ± 2.3 mGy. After protocol modification, the mean CTDI decreased to 6.63 ± 0.67 mGy, a 59.6% reduction overall; for hepatic ablations, the reduction was 65.96% (p < 0.0001) and the reduction for renal ablations was 38.97% (p = 0.0153). Image quality analysis showed high operator satisfaction (3-5), including adequate needle localization (4-5), lesion visibility (3-5), and high performer confidence (4-5). Higher dose reduction was noted for patients weighing more than 180 lb (82 kg) (p < 0.0001). CONCLUSION: Simple weight-based CT protocol modifications can significantly reduce radiation dose during CT-guided percutaneous ablations in the liver and kidneys without significantly sacrificing image quality.

Efecto reno-protector y reno-reparador del Factor de Crecimiento Epidérmico en biomodelo de Insuficiencia Renal Crónica / Reno-protective and reno-restorative effect of the Epidermal Growth Factor in biomodel of Chronic Renal Failure

Introducción: La Enfermedad Renal es un problema de salud mundial. El Factor de Crecimiento Epidérmico actúa como citoprotector y trófico reparador. Objetivo: Evaluar el efecto reno-protector y reno-reparador del Factor de Crecimiento Epidérmico en biomodelo de Insuficiencia Renal Crónica. Material y Métodos: Se estudiaron 120 ratas, Wistar, en 6 grupos: Control Negativo y positivo, Solución Salina Dosis Única y Múltiple, Factor de Crecimiento Epidérmico Dosis Única y Múltiple. Se aplicó para efecto reno-protector dosis única antes del daño, y para el reno-reparador dosis múltiples posterior al daño, a razón de 100 µg/kg de peso. Resultados: La creatinina, urea y ácido úrico disminuyeron significativamente en los grupos experimentales, con mayor disminución para el grupo experimental dosis única, por lo que el efecto reno-protector fue mayor que el reno-reparador para los esquemas de tratamiento utilizados. Conclusiones: El Factor de Crecimiento Epidérmico mostró efecto reno-protector y reno-reparador al disminuir las variables hematológicas de daño renal(AU)

Introduction: Kidney disease is a world health problem. Epidermic Growth Factor acts as cyto-protector, and trophic restorative. Objective: To assess the reno-protective and reno-restorative effect of the Epidermal Growth Factor in biomodel of Chronic Renal Failure. Material and Methods: 120 Wistar rats were studied in 6 groups: Negative and Positive Control, Saline Solution Single-Dose and Multiple-Dose, Epidermal Growth Factor Single-Dose and Multiple-Dose. A single dose was applied before the damage for the reno-protective effect, and multiple doses after the damage for the reno-restorative effect, at a rate of 100 µg/kg of weight. Results: Creatinine, urea, and uric acid diminished significantly in the experimental groups, with a higher decrease for experimental group with single dose; therefore, the reno-protective effect was higher than reno-restorative one for the treatment patterns used. Conclusions: Epidermal Growth Factor showed reno-protective and reno-restorative effect by diminishing the hematological variables in kidney damage(AU)

Tips and tricks for a safe and effective image-guided percutaneous renal tumour ablation.

Image-guide thermal ablations are nowadays increasingly used to provide a minimally invasive treatment to patients with renal tumours, with reported good clinical results and low complications rate. Different ablative techniques can be applied, each with some advantages and disadvantages according to the clinical situation. Moreover, percutaneous ablation of renal tumours might be complex in cases where there is limited access for image guidance or a close proximity to critical structures, which can be unintentionally injured during treatment. In the present paper we offer an overview of the most commonly used ablative techniques and of the most important manoeuvres that can be applied to enhance the safety and effectiveness of percutaneous image-guided renal ablation. Emphasis is given to the different technical aspects of cryoablation, radiofrequency ablation, and microwave ablation, on the ideal operating room setting, optimal image guidance, application of fusion imaging and virtual navigation, and contrast enhanced ultrasound in the guidance and monitoring of the procedure. Moreover, a series of protective manoeuvre that can be used to avoid damage to surrounding sensitive structures is presented. A selection of cases of image-guided thermal ablation of renal tumours in which the discussed technique were used is presented and illustrated. TEACHING POINTS: • Cryoablation, radiofrequency and microwave ablation have different advantages and disadvantages. • US, CT, fusion imaging, and CEUS increase an effective image-guidance. • Different patient positioning and external compression may increase procedure feasibility. • Hydrodissection and gas insufflation are useful to displace surrounding critical structures. • Cold pyeloperfusion can reduce the thermal damage to the collecting system.

Laparoscopic approach to colo-renal fistula with renal preservation and omentoplasty: A case report.

Colorenal fistula as a result of percutaneous cryoablation has not been extensively reported. We report a gentleman who presented with urosepsis after percutaneous biopsy of a renal mass complicated by colorenal fistula. After failed attempts at conservative management, he underwent laparoscopic resection of his fistula with renal salvage and omentoplasty highlighting that nephrectomy is not always indicated.

Microwave ablation of renal tumors: A narrative review of technical considerations and clinical results.

PURPOSE: The purpose of this review was to identify the specific technical considerations to adequately perform microwave ablations (MWA) of renal tumors and analyze the currently available clinical results. METHODS: Using Medline, a systematic review was performed including articles published between January 2000 and September 2016. English language original articles, reviews and editorials were selected based on their clinical relevance. RESULTS: MWA has several theoretical advantages over radiofrequency ablation in consistently providing higher intratumoral temperatures. MWA is less dependent of electrical conductivities of tissues and the delivered energy is less limited by desiccation of heated tissues. While there are insufficient data, especially because of a lack of studies with mid- to long-term follow-up, to determine the oncologic effectiveness of MWA, this technique appears safe and effective for the ablation of T1 renal tumors. There is evidence for using mid-level settings based on experimental and clinical data. Power set at 50-65W for 5-15min appears adequate in kidney but close clinical and imaging follow-up have to be performed. CONCLUSION: Renal MWA offers theoretical advantages by comparison with other available techniques to treat renal tumors. However, MWA suffers of less cumulative data compared to radiofrequency ablation or cryoablation. Moreover, microwaves still require further studies to identify the optimal tumor characteristics and device settings leading to predictable ablation.

Discoidin domain receptor 1 kinase activity is required for regulating collagen IV synthesis.

Discoidin domain receptor 1 (DDR1) is a receptor tyrosine kinase that binds to and is activated by collagens. DDR1 expression increases following kidney injury and accumulating evidence suggests that it contributes to the progression of injury. To this end, deletion of DDR1 is beneficial in ameliorating kidney injury induced by angiotensin infusion, unilateral ureteral obstruction, or nephrotoxic nephritis. Most of the beneficial effects observed in the DDR1-null mice are attributed to reduced inflammatory cell infiltration to the site of injury, suggesting that DDR1 plays a pro-inflammatory effect. The goal of this study was to determine whether, in addition to its pro-inflammatory effect, DDR1 plays a deleterious effect in kidney injury by directly regulating extracellular matrix production. We show that DDR1-null mice have reduced deposition of glomerular collagens I and IV as well as decreased proteinuria following the partial renal ablation model of kidney injury. Using mesangial cells isolated from DDR1-null mice, we show that these cells produce significantly less collagen compared to DDR1-null cells reconstituted with wild type DDR1. Moreover, mutagenesis analysis revealed that mutations in the collagen binding site or in the kinase domain significantly reduce DDR1-mediated collagen production. Finally, we provide evidence that blocking DDR1 kinase activity with an ATP-competitive small molecule inhibitor reduces collagen production. In conclusion, our studies indicate that the kinase activity of DDR1 plays a key role in DDR1-induced collagen synthesis and suggest that blocking collagen-mediated DDR1 activation may be beneficial in fibrotic diseases.

Does significant renal ablation truly and invariably lead to hyperfiltration and progressive chronic kidney disease?

It is generally believed that significant renal ablation leads to hyperfiltration and eventually progressively worsening chronic kidney disease. The data behind this belief have not been scrutinized intensively. More importantly, the above belief leads many physicians to manage patients differently than they otherwise would manage. Here, we examine the data behind whether hyperfiltration occurs when patients lose kidney mass (by excision or by disease) and whether the hyperfiltration is uniformly injurious.

Percutaneous radiofrequency ablation of renal tumors in high-risk patients: 10 years' experience. / Ablación percutánea mediante radiofrecuencia de tumores renales en pacientes de alto riesgo: 10 años de experiencia.

OBJECTIVE: To retrospectively evaluate the efficacy and safety of percutaneous radiofrequency ablation (RFA) done to treat renal tumors in patients with high surgical risk or with the risk of developing multiple renal tumors in the medium term at our center over a period of 10 years. MATERIAL AND METHODS: Between 2005 and 2015, we used RFA to treat 89 T1a or T1b tumors in 87 patients (mean age, 73.7±10.87 years) with high surgical risk. We excluded patients treated with radiofrequency and embolization or microwave ablation. The tumors treated were clear cell carcinomas (43.6%), papillary renal carcinomas (17.2%), chromophobe renal cell carcinomas (10.3%), cystic tumors (2.2%), and an angiomyolipoma (1.1%). The mean size of the tumors was 2.6cm. Computed tomography and/or ultrasonography were used to guide the procedure. We analyzed the relation between the efficacy of the procedure and patients' age, the type of needle, the source of the patients, the size and location of the tumor, and the number of sessions required to achieve ablation. We recorded all complications. RESULTS: The RFA procedure was completed in all patients. The mean follow-up period was 32.1 months. The efficacy was 93.7%. A single session was sufficient in 87.5% of patients; 8% required two sessions and 4.5% required three sessions. The only factor associated with worse efficacy was the size of the tumor (p=0.03). The rate of complications was 5.6%. CONCLUSIONS: RFA is efficacious and safe, with results comparable to those reported in the literature.

Renal ablation using magnetic resonance-guided high intensity focused ultrasound: Magnetic resonance imaging and histopathology assessment.

AIM: To use magnetic resonance-guided high intensity focused ultrasound (MRg-HIFU), magnetic resonance imaging (MRI) and histopathology for noninvasively ablating, quantifying and characterizing ablated renal tissue. METHODS: Six anesthetized/mechanically-ventilated pigs underwent single/double renal sonication (n = 24) using a 3T-MRg-HIFU (1.1 MHz frequency and 3000J-4400J energies). T2-weighted fast spin echo (T2-W), perfusion saturation recovery gradient echo and contrast enhanced (CE) T1-weighted (T1-W) sequences were used for treatment planning, temperature monitoring, lesion visualization, characterization and quantification, respectively. Histopathology was conducted in excised kidneys to quantify and characterize cellular and vascular changes. Paired Student's t-test was used and a P-value < 0.05 was considered statistically significant. RESULTS: Ablated renal parenchyma could not be differentiated from normal parenchyma on T2-W or non-CE T1-W sequences. Ablated renal lesions were visible as hypoenhanced regions on perfusion and CE T1-W MRI sequences, suggesting perfusion deficits and necrosis. Volumes of ablated parenchyma on CE T1-W images in vivo (0.12-0.36 cm(3) for single sonication 3000J, 0.50-0.84 cm(3), for double 3000J, 0.75-0.78 cm(3) for single 4400J and 0.12-2.65 cm(3) for double 4400J) and at postmortem (0.23-0.52 cm(3), 0.25-0.82 cm(3), 0.45-0.68 cm(3) and 0.29-1.80 cm(3), respectively) were comparable. The ablated volumes on 3000J and 4400J double sonication were significantly larger than single (P < 0.01), thus, the volume and depth of ablated tissue depends on the applied energy and number of sonication. Macroscopic and microscopic examinations confirmed the locations and presence of coagulation necrosis, vascular damage and interstitial hemorrhage, respectively. CONCLUSION: Contrast enhanced MRI provides assessment of MRg-HIFU renal ablation. Histopathology demonstrated coagulation necrosis, vascular damage and confirmed the volume of damage seen on MRI.

Contemporary Status of Percutaneous Ablation for the Small Renal Mass.

Renal cell carcinoma is the tenth most common malignancy in the USA, with upwards of 61,000 new cases and resulting in more than 14,000 deaths annually. Although partial nephrectomy remains the standard treatment, image-guided nephron-sparing ablative techniques including cryoablation, radiofrequency ablation, and microwave ablation have emerged as treatment options in certain patient populations. Ablative therapies have high technical successes, low tumor recurrence rates, and preserve renal parenchymal volume. The purpose of this article is to provide an update on ablation therapies for small renal masses.