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Purpose: To evaluate the response of the ureter and renal pelvis to direct targeting by histotripsy guided by cone-beam computed tomography (CT) in a human-scale porcine chronic-survival model., Materials and Methods: Bilateral ureteral histotripsy treatments were completed on 6 female swine (n = 12). Animals were divided into 2 groups: (a) acute (n = 2 animals, 4 treatments, sacrificed at Day 0) and (b) chronic (n = 4 animals, 8 treatments, sacrificed at Day 7 [n = 2] and Day 28 [n = 2]). For each treatment, a 2.5-cm sphere (ureter/renal pelvis and renal parenchyma) was targeted using cone-beam CT guidance. CT urography imaging was performed immediately after treatment for all animals, and on Days 7 and 28 for chronic animals, followed by sacrifice, necropsy, and histopathology. Serum chemistries were drawn before treatment and at Days 7 and 28., Results: All 12 treatments were successful in targeting the renal pelvis/ureter and renal parenchyma. CT urography findings at Day 0 included ureteral thickening (9/12), delayed parenchymal enhancement (3/12), and mild hydronephrosis (5/12), all resolving by Day 7. Histologic findings of low-grade damage resolved by Day 7. No urine leaks or ureteral strictures were observed. Renal function (creatinine and estimated glomerular filtration rate) remained within the normal range throughout the study., Conclusions: Histotripsy treatment of the ureter and renal pelvis results in transient injuries, suggesting that treatment of central renal tumors adjacent to the ureter and renal pelvis is safe. The results of this study could help expand the range of renal tumors that can be treated with histotripsy., (Copyright © 2024 SIR. All rights reserved.)

Purpose: To evaluate safety and oncologic efficacy of percutaneous microwave ablation (MWA) for treating clinically localized T1b (cT1b) renal cell carcinoma (RCC)., Methods: This single-center retrospective study was performed under a waiver of informed consent. Seventy-four consecutive patients (49M/25F) with 76 cT1b RCC (median tumor diameter 4.5 cm) were treated with percutaneous MWA between 5/2012 and 8/2020. Patients were stratified into two groups by technique, depending on whether antennas were repositioned for additional ablation or not. Primary efficacy, complications, and local tumor progression (LTP) were compared using the Wilcoxon rank sum and Fisher's exact tests. The Kaplan Meier method was used for survival analysis., Results: Patients were elderly (median age 69.5), obese (median BMI 34.5), and comorbid (Charlson Comorbidity Index = 4). Most tumors were low-grade (grade 1-2) (67/89, 88%) and clear cell RCC was the most common histology (62/76, 82%). A median of three MWA antennas were powered at 65 W for 7 min for treatment. Renal masses were larger (4.6 vs 4.5 cm, p = 0.01) and procedure times longer (100 min vs 80.5 min, p = 0.04) for the antenna reposition cohort (n = 34, 45%). Primary efficacy and high-grade complication rates were 93% and 8%, respectively. The local tumor progression rate (LTP), at a median follow-up was 28.2 months, was 16%. Primary efficacy, low and high-grade complications, change in estimated glomerular filtration rate and LTP were similar between cohorts (p = 0.20-0.55)., Conclusion: Percutaneous MWA for cT1b RCC is safe in elderly and comorbid patients with acceptable oncologic efficacy. Repeat ablation is well-tolerated and can improve oncologic efficacy., Competing Interests: Declarations. Conflict of interest: SAW, JLH, and TJZ are consultants for Ethicon Inc. The other authors, have no relevant financial or non-financial interests to disclose., (© 2025. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Introduction: The prevalence of preoperative paraneoplastic syndromes (PNS) in renal cell carcinoma (RCC) is poorly understood. Many laboratory abnormalities representative of PNS have demonstrated prognostic value when incorporated into predictive survival models in RCC. We sought to characterize the relationship between baseline prevalence of PNS with overall survival (OS) and cancer-specific survival (CSS) in RCC patients following nephrectomy., Methods: Our prospectively maintained nephrectomy database was retrospectively reviewed for any stage, major histology RCC patients that underwent surgery from 2000 to 2022. Baseline laboratory values within 90 days (closest used) were required. Presence of PNS was defined according to established laboratory cutoffs. Kaplan-Meier curves estimated survival rates, and multivariable Cox proportional hazards models examined the association between PNS with OS and CSS following nephrectomy., Results: 2599 patients were included with listed staging: 1494 Stage I; 180 Stage II; 616 Stage III; 306 Stage IV. Proportion of patients presenting with >1 PNS significantly increased from stage I (31.3%) to stage IV (74.2%) RCC (P < .001). Elevated C-reactive protein was the most prevalent PNS (45.4%). On multivariable analysis, the presence of >1 PNS was associated with higher risk of all-cause (HR 2.09; P < .001) and cancer-specific mortality (HR 2.55; P < .001). The 10-year OS estimates as reported: 65.2% (no PNS), 52.3% (1 PNS), 36.6% (>1 PNS); and 10-year CSS estimates: 88.3% (no PNS), 79.3% (1 PNS), 61.6% (>1 PNS)., Discussion: Increased prevalence of PNS in major histology RCC was associated with a significant increase in the risk of all-cause and cancer-specific mortality even when accounting for patient and disease characteristics., Competing Interests: Disclosure The authors have stated that they have no conflicts of interest., (Copyright © 2024. Published by Elsevier Inc.)

Background/Objectives: The presence of paraneoplastic syndromes (PNS) in patients with renal cell carcinoma (RCC) is associated with worse survival; however, little is known about whether resolution of PNS after intervention has any prognostic value. We sought to determine if resolution of PNS by one year after cytoreductive nephrectomy was significantly associated with improved overall survival (OS) and cancer-specific survival (CSS). Methods: We retrospectively reviewed a prospectively maintained nephrectomy database for patients with any histology metastatic RCC (mRCC) who underwent nephrectomy between 2000 and 2022. Patients with the necessary laboratory studies available within 90 days before and by one year after surgery were included for study. PNS resolution was defined as an abnormal value compared to established laboratory cutoffs by one year after surgery. Multiple PNS in one patient was allowed, and resolution of each PNS was measured separately. OS and CSS were assessed using Kaplan-Meier curves and Cox proportional hazards models. Results: A total of 253 patients met inclusion criteria. A total of 177 patients (70.0%) met criteria for at least one PNS resolution by one year. Five-year OS and CSS rates were 15.7% and 36.2% for no PNS resolved, 24.5% and 31.6% for 1 PNS resolved, and 43.0% and 58.2% for ≥2 PNS resolved, respectively ( p < 0.001). On multivariable analysis, no PNS resolution was associated with worse OS (HR 2.75, p < 0.001) and CSS (HR 2.62, p < 0.001) compared to ≥2 PNS resolved. Conclusions: Resolution of preoperative PNS abnormalities by one year following surgery is associated with improved OS and CSS in patients with mRCC.

Background: The standard of care for patients with intermediate-to-high risk renal cell carcinoma is partial or radical nephrectomy followed by surveillance. We aimed to investigate use of nivolumab before nephrectomy followed by adjuvant nivolumab in patients with high-risk renal cell carcinoma to determine recurrence-free survival compared with surgery only., Methods: In this open-label, randomised, phase 3 trial (PROSPER EA8143), patients were recruited from 183 community and academic sites across the USA and Canada. Eligible patients were aged 18 years or older with an Eastern Cooperative Oncology Group performance status of 0-1, with previously untreated clinical stage T2 or greater or T any N+ renal cell carcinoma of clear cell or non-clear cell histology planned for partial or radical nephrectomy. Selected patients with oligometastatic disease, who were disease free at other disease sites within 12 weeks of surgery, were eligible for inclusion. We randomly assigned (1:1) patients using permuted blocks (block size of 4) within stratum (clinical TNM stage) to either nivolumab plus surgery, or surgery only followed by surveillance. In the nivolumab group, nivolumab 480 mg was administered before surgery, followed by nine adjuvant doses. The primary endpoint was investigator-reviewed recurrence-free survival in patients with renal cell carcinoma assessed in all randomly assigned patients regardless of histology. Safety was assessed in all randomly assigned patients who started the assigned protocol treatment. This trial is registered with ClinicalTrials.gov, NCT03055013, and is closed to accrual., Findings: Between Feb 2, 2017, and June 2, 2021, 819 patients were randomly assigned to nivolumab plus surgery (404 [49%]) or surgery only (415 [51%]). 366 (91%) of 404 patients assigned to nivolumab plus surgery and 387 (93%) of 415 patients assigned to surgery only group started treatment. Median age was 61 years (IQR 53-69), 248 (30%) of 819 patients were female, 571 (70%) were male, 672 (88%) were White, and 77 (10%) were Hispanic or Latino. The Data and Safety Monitoring Committee stopped the trial at a planned interim analysis (March 25, 2022) because of futility. Median follow-up was 30·4 months (IQR 21·5-42·4) in the nivolumab group and 30·1 months (21·9-41·8) in the surgery only group. 381 (94%) of 404 patients in the nivolumab plus surgery group and 399 (96%) of 415 in the surgery only group had renal cell carcinoma and were included in the recurrence-free survival analysis. As of data cutoff (May 24, 2023), recurrence-free survival was not significantly different between nivolumab (125 [33%] of 381 had recurrence-free survival events) versus surgery only (133 [33%] of 399; hazard ratio 0·94 [95% CI 0·74-1·21]; one-sided p=0·32). The most common treatment-related grade 3-4 adverse events were elevated lipase (17 [5%] of 366 patients in the nivolumab plus surgery group vs none in the surgery only group), anaemia (seven [2%] vs nine [2%]), increased alanine aminotransferase (ten [3%] vs one [<1%]), abdominal pain (four [1%] vs six [2%]), and increased serum amylase (nine [2%] vs none). 177 (48%) patients in the nivolumab plus surgery group and 93 (24%) in the surgery only group had grade 3-5 adverse events due to any cause, the most common of which were anaemia (23 [6%] vs 19 [5%]), hypertension (27 [7%] vs nine [2%]), and elevated lipase (18 [5%] vs six [2%]). 48 (12%) of 404 patients in the nivolumab group and 40 (10%) of 415 in the surgery only group died, of which eight (2%) and three (1%), respectively, were determined to be treatment-related., Interpretation: Perioperative nivolumab before nephrectomy followed by adjuvant nivolumab did not improve recurrence-free survival versus surgery only followed by surveillance in patients with high-risk renal cell carcinoma., Funding: US National Institutes of Health National Cancer Institute and Bristol Myers Squibb., Competing Interests: Declaration of interests VM reports support for attending meetings or travel from American College of Surgeons; and participation on the Advisory Board on Diversity, Equity, and Inclusion at Exelixis. VM also reports a leadership role (unpaid) on Society of Urologic Oncology Clinical Trials Consortia. DFM received payment or honoraria from Bristol Myers Squibb, Pfizer, Merck, Eisai, Xilio, Aveo, Genentech, Cullinan, and Exelixis; and support for attending meetings or travel from Bristol Myers Squibb, Merck, Genentech, Pfizer, Exelixis, X4 Pharma, and Alkermes. LCH reports ownership of stock in Coherus and previous employment at Surface Oncology. SS reports grants or contracts from Bristol Myers Squibb and Exelixis to their institution; and royalties or licenses from Biogenex. SS also reports consulting fees from AstraZeneca, Merck, and CRISPR Therapeutics; and a leadership or fiduciary role at American Association for Cancer Research as Senior Editor at Clinical Cancer Research and at the NCI National Cancer Institute as Renal Task Force Co-Chair. HE reports consulting fees for Janssen and Aveo advisory boards. NA reports grants or contracts from Exelixis, Genentech, Merck, and Bristol Myers Squibb; and consulting fees from Exelixis, Bristol Myers Squibb, Aveo, Merck, EMD Serono, and Sanofi. MAB reports institutional grants from Merck, Xencor, Bayer, Bristol Myers Squibb, Genentech/Roche, SeaGen, Incyte, Nektar, AstraZeneca, Tricon Pharmaceuticals, Genome & Company, AAA, Peloton Therapeutics, and Pfizer; and payment or honoraria for Advisory Board participation from Exelixis, Bayer, Bristol Myers Squibb, Eisai, Pfizer, AstraZeneca, Janssen, Calithera Biosciences, Genomic Health, Nektar, EMD Serono, SeaGen, and Sanofi. TMM reports payment to their institution for clinical trials from Merck, Curium, and ECOG; consulting fees from Impact Network and Aptitude Health; and honoraria from Exelixis and Blue Earth Diagnostics. TC reports support from Alkermes, AstraZeneca, Aravive, Aveo, Bayer, Bristol Myers Squibb, Calithera, Circle Pharma, Deciphera Pharmaceuticals, Eisai, EMD Serono, Exelixis, GlaxoSmithKline, Gilead, HiberCell, IQVIA, Infinity, Ipsen, Jansen, Kanaph, Lilly, Merck, Nikang, Neomorph, Nuscan/PrecedeBio, Novartis, Oncohost, Pfizer, Roche, Sanofi/Aventis, Scholar Rock, Surface Oncology, Takeda, Tempest, Up-To-Date, and CME events (Peerview, OncLive, MJH, CCO, and others), outside the submitted work. TC also reports institutional research funding related to clinical trials from AstraZeneca, Aveo, Arcus, Bayer, Bristol Myers Squibb, Eisai, EMD Serono, Exelixis, GlaxoSmithKline, Lilly, Merck, Nikang, Novartis, Pfizer, Roche, Sanofi/Aventis, and Takeda. TC also reports consulting fees from Alkermes, AstraZeneca, Aravive, Aveo, Bayer, Bristol Myers Squibb, Calithera, Circle Pharma, Deciphera Pharmaceuticals, Eisai, EMD Serono, Exelixis, GlaxoSmithKline, Gilead, HiberCell, IQVIA, Infinity, Ipsen, Jansen, Kanaph, Lilly, Merck, Nikang, Neomorph, Nuscan/PrecedeBio, Novartis, Oncohost, Pfizer, Roche, Sanofi/Aventis, Scholar Rock, Surface Oncology, Takeda, Tempest, Up-To-Date, CME events (Peerview, OncLive, MJH, CCO, and others), outside the submitted work. TC also reports payment or honoraria from Alkermes, AstraZeneca, Aravive, Aveo, Bayer, Bristol Myers Squibb, Calithera, Circle Pharma, Deciphera Pharmaceuticals, Eisai, EMD Serono, Exelixis, GlaxoSmithKline, Gilead, HiberCell, IQVIA, Infinity, Ipsen, Jansen, Kanaph, Lilly, Merck, Nikang, Neomorph, Nuscan/PrecedeBio, Novartis, Oncohost, Pfizer, Roche, Sanofi/Aventis, Scholar Rock, Surface Oncology, Takeda, Tempest, Up-To-Date, CME events (Peerview, OncLive, MJH, CCO, and others), outside the submitted work. TC also reports support for attending meetings or travel in relation to meetings, lectures, and advisory boards; and participates in the Aravive Data and Safety Monitoring Board or advisory board. TC also reports a patent related to ctDNA and biomarkers of response to immune checkpoint inhibitors (no royalties as of current date). TC also reports a leadership or fiduciary role in KidneyCan (unpaid) and committees for American Society of Clinical Oncology, European Society of Medical Oncology, National Comprehensive Cancer Network, and Genitourinary Steering Committee of the NCI. TC also reports stock ownership (for being an advisor) of Pionyr, Tempest, Precede Bio, Osel, Curesponse, Immdura, and Primium. TC also reports no receipt of equipment, materials, drugs, medical writing, gifts, or other services, except for travel and accommodation (flights, hotel, and meals) related to advisory or consulting when travel needed. TC also reports to be supported in part by the Dana-Farber/Harvard Cancer Center Kidney SPORE(2P50CA101942-16) and Program 5P30CA006516-56, the Kohlberg Chair at Harvard Medical School and the Trust Family, Michael Brigham, Pan-Mass Challenge, Hinda and Arthur Marcus Fund, and Loker Pinard Funds for Kidney Cancer Research at Dana Farber Cancer Institute. MDD reports participation on the Scientific Advisory Boards (honoraria received) at Merck, Eisai, Exelixis, and Janssen. DYH reports compensation from consulting work from Bristol Myers Squibb, Merck, Ipsen, Exelixis, Pfizer, and Eisai. BS reports consulting fees from Merck, Veracyte, Telix, and Johnson and Johnson; payment or honoraria from Merck; and receipt of equipment, materials, drugs, medical writing, gifts, or other services from Telix. BCL reports a leadership or fiduciary role at Kidney Cancer Association as Chair of Board of Directors. JM reports participation on the NCI Central Institutional Review Board and has been recused from all discussions of this study. RU reports participation and financial support on a Data Safety Monitoring Board at Pfizer and other financial support on a steering committee at Merck. RU also reports a leadership or fiduciary role (non-financial support) at Haymarket Media as a board member. GB reports a leadership role during the study as President of the Society of Urologic Oncology–Clinical Trial Consortium. NBH reports participation in the Data and Safety Monitoring Committee atezolizumab at Roche Genentech and advisory boards at Bristol Myers Squibb and Eisai. NBH also reports a non-financial leadership role as ECOG ACRIN Genitourinary Committee Co-Chair. All other authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved, including those for text and data mining, AI training, and similar technologies.)

Background: Careful patient selection is critical when considering cytoreductive nephrectomy (CN) for metastatic renal cell carcinoma (mRCC) but few studies have investigated the prognostic value of radiologic features that measure tumor burden., Objective: To develop a prognostic model to improve CN selection with integration of common radiologic features with known prognostic factors associated with mortality in the first year following surgery., Design, Settings, and Participants: Data were analyzed for consecutive patients with mRCC treated with upfront CN at five institutions from 2006 to 2017. Univariable and multivariable models were used to evaluate radiographic features and known risk factors for associations with overall survival. Relevant factors were used to create the SCREEN model and compared to the International mRCC Database Consortium (IMDC) model for predictive accuracy and clinical usefulness., Results and Limitations: A total of 914 patients with mRCC were treated with upfront CN during the study period. Seven independently predictive variables were used in the SCREEN score: three or more metastatic sites, total metastatic tumor burden ≥5 cm, bone metastasis, systemic symptoms, low serum hemoglobin, low serum albumin, and neutrophil/lymphocyte ratio ≥4. Predictive accuracy measured as the area under the receiver operating characteristic curves was 0.76 for the SCREEN score and 0.55 for the IMDC model. Decision curve analysis showed that the SCREEN model was useful beyond the IMDC classifier for threshold first-year mortality probabilities between 15% and 70%., Conclusions: The SCREEN score had higher predictive accuracy for first-year mortality compared to the IMDC scheme in a multi-institutional cohort and may be used to improve CN selection., Patient Summary: This study provides a model to improve selection of patients with metastatic kidney cancer who may benefit from surgical removal of the primary kidney tumor. We found that radiographic measurements of the tumor burden predicted the risk of death in the first year after surgery. The model can be used to improve decision-making by these patients and their physicians., (Copyright © 2023. Published by Elsevier B.V.)

Purpose To determine if microwave ablation (MWA) of retroperitoneal tumors can safely provide high rates of local tumor control. Materials and Methods This retrospective study included 19 patients (median age, 65 years [range = 46-78 years]; 13 [68.4%] men and six [31.6%] women) with 29 retroperitoneal tumors treated over 22 MWA procedures. Hydrodissection (0.9% saline with 2% iohexol) was injected in 17 of 22 (77.3%) procedures to protect nontarget anatomy. The primary outcomes evaluated were local tumor progression (LTP) and complication rates. Oncologic outcomes, including overall survival (OS), progression-free survival (PFS), and treatment-free interval (TFI), were examined as secondary outcome measures. Results Median follow-up was 18 months (range = 0.5-113). Hydrodissection was successful in displacing nontarget anatomy in 16 of 17 (94.1%) procedures. The LTP rate was 3.4% (one of 29; 95% CI: 0.1, 17.8) per tumor and 5.3% (one of 19; 95% CI: 0.1, 26.0) per patient. The overall complication rate per patient was 15.8% (three of 19), including two minor complications and one major complication. The OS rate at 1, 2, and 3 years was 81.8%, 81.8%, and 72.7%, respectively, with a median OS estimated at greater than 7 years. There was no evidence of a difference in OS ( P = .34) and PFS ( P = .56) between patients with renal cell carcinoma (six of 19 [31.6%]) versus other tumors (13 of 19 [68.4%]) and patients treated with no evidence of disease (15 of 22 [68.2%]) versus patients with residual tumors (seven of 22 [31.8%]). Median TFI was 18 months (range = 0.5-108). Conclusion Treatment of retroperitoneal tumors with MWA combined with hydrodissection provided high rates of local control, prolonged systemic therapy-free intervals, and few serious complications. Keywords: Ablation Techniques (ie, Radiofrequency, Thermal, Chemical), Retroperitoneum, Microwave Ablation, Hydrodissection © RSNA, 2024.

Predicting which patients will progress to metastatic disease after surgery for non-metastatic clear cell renal cell carcinoma (ccRCC) is difficult; however, recent data suggest that tumor immune cell infiltration could be used as a biomarker. We evaluated the quantity and type of immune cells infiltrating ccRCC tumors for associations with metastatic progression following attempted curative surgery. We quantified immune cell densities in the tumor microenvironment and validated our findings in two independent patient cohorts with multi-region sampling to investigate the impact of heterogeneity on prognostic accuracy. For non-metastatic ccRCC, increased CD8 + T cell infiltration was associated with a reduced likelihood of progression to metastatic disease. Interestingly, patients who progressed to metastatic disease also had increased percentages of exhausted CD8 + T cells. Finally, we evaluated the spatial heterogeneity of the immune infiltration and demonstrated that patients without metastatic progression had CD8 + T cells in closer proximity to ccRCC cells. These data strengthen the evidence for CD8 + T cell infiltration as a prognostic biomarker in non-metastatic ccRCC and demonstrate that multi-region sampling may be necessary to fully characterize immune infiltration within heterogeneous tumors. Tumor CD8 + T cell infiltration should be investigated as a biomarker in adjuvant systemic therapy clinical trials for high-risk non-metastatic RCC.

Objective: To evaluate factors associated with perioperative outcomes in a multi-institutional cohort of patients treated with cytoreductive nephrectomy (CN)., Methods: Data were analyzed for metastatic renal cell carcinoma patients treated with CN at 6 tertiary academic centers from 2005 to 2019. Outcomes included: Clavien-Dindo complications, mortality, length of hospitalization, 30-day readmission rate, and time to systemic therapy. Univariate and multivariable models evaluated associations between outcomes and prognostic variables including the year of surgery., Results: A total of 1272 consecutive patients were treated with CN. Patients treated in 2015-2019 vs 2005-2009 had better performance status (P<.001), higher pathologic N stage (P = .04), more frequent lymph node dissections (P<.001), and less frequent presurgical therapy (P = .02). Patients treated in 2015-2019 vs 2005-2009 had lower overall and major complications from surgery, 22% vs 39%, P<.001% and 10% vs 16%, P = .03. Mortality at 90days was higher for patients treated 2005-2009 vs 2015-2019; 10% vs 5%, P = .02. After multivariable analysis, surgical time period was an independent predictor of major complications and 90-day mortality following cytoreductive surgery., Conclusion: Postoperative major complications and mortality rates following CN are significantly lower in patients treated within the most recent time period., Competing Interests: Declaration of Competing Interest The authors have no conflict of interest to declare., (Copyright © 2023. Published by Elsevier Inc.)

Purpose: To compare the safety and efficacy of histotripsy with cryoablation in a chronic human-scale normal porcine kidney model., Materials and Methods: Eighteen female domestic swine were divided evenly into histotripsy and cryoablation treatment arms. A planned 2-3 cm diameter treatment was performed under ultrasound (histotripsy) or ultrasound and computed tomography (CT) guidance (cryoablation). Contrast-enhanced CT and serum blood analysis were performed immediately postprocedure and on day 7, with either immediate killing (n = 3) or continued survival to day 30 (n = 6), at which time contrast-enhanced CT, serum blood analysis, and necropsy were performed. Animal welfare, treatment zone appearance, procedure-related adverse events, and histopathology of the treatment zones and surrounding tissues were assessed., Results: Histotripsy treatment zones (mean ±standard deviation diameters, 2.7 ± 0.12 × 2.4 ± 0.19 × 2.4 ± 0.26 cm; volume, 8.3 ± 1.9 cm 3 ) were larger than cryoablation zones (mean diameters, 2.2 ± 0.19 × 1.9 ± 0.13 × 1.7 ± 0.19 cm; volume, 3.9 ± 0.8 cm 3 ; P < .001). At 30 days, histotripsy and cryoablation treatment zone volumes decreased by 96% and 83% on CT, respectively (P < .001). Perirenal hematomas were present after 8 of 9 (89%) cryoablation (mean volume, 22.2 cm 3 ) and 1 of 9 (11%, P < .001) histotripsy (volume, 0.4 cm 3 ) procedures, with active arterial extravasation in 4 of 9 (44%) cryoablation and no histotripsy animals (P = .206). All 9 histotripsy animals and 5 of 9 (56%) cryoablation animals had collecting system debris (P = .042). Changes in serum creatinine were similar between the groups (P = .321)., Conclusions: Other than a higher rate of bleeding after cryoablation, the safety and early efficacy of histotripsy and cryoablation were comparable for creating treatment zones in a chronic normal porcine kidney model., (Copyright © 2023 SIR. All rights reserved.)

Cytoreductive nephrectomy became accepted as standard of care for selected patients with metastatic renal cell carcinoma (mRCC) because of improved survival observed in patients treated with cytoreductive nephrectomy in combination with interferon-α in two randomized clinical trials published in 2001. Over the past two decades, novel systemic therapies have shown higher treatment response rates and improved survival outcomes compared with interferon-α. During this rapid evolution of mRCC treatments, systemic therapies have been the primary focus of clinical trials. Results from multiple retrospective studies continue to suggest an overall survival benefit for selected patients treated with nephrectomy in combination with systemic mRCC treatments, with the notable exception of one debated clinical trial. The optimal timing for surgery is unknown, and proper patient selection remains crucial to improving surgical outcomes. As systemic therapies continue to evolve, clinicians have an increasing need to understand how to incorporate cytoreductive nephrectomy into the management of mRCC., (© 2023. Springer Nature Limited.)

Scientific understanding of how the immune microenvironment interacts with renal cell carcinoma (RCC) has substantially increased over the last decade as a result of research investigations and applying immunotherapies, which modulate how the immune system targets and eliminates RCC tumor cells. Clinically, immune checkpoint inhibitor therapy (ICI) has revolutionized the treatment of advanced clear cell RCC because of improved outcomes compared to targeted molecular therapies. From an immunologic perspective, RCC is particularly interesting because tumors are known to be highly inflamed, but the mechanisms underlying the inflammation of the tumor immune microenvironment are atypical and not well described. While technological advances in gene sequencing and cellular imaging have enabled precise characterization of RCC immune cell phenotypes, multiple theories have been suggested regarding the functional significance of immune infiltration in RCC progression. The purpose of this review is to describe the general concepts of the anti-tumor immune response and to provide a detailed summary of the current understanding of the immune response to RCC tumor development and progression. This article describes immune cell phenotypes that have been reported in the RCC microenvironment and discusses the application of RCC immunophenotyping to predict response to ICI therapy and patient survival.

Purpose: To determine the risk of mechanical vessel wall damage resulting in hemorrhage during and after hepatic and renal histotripsy in an anticoagulated in vivo porcine model., Materials and Methods: Non-tumor-bearing pigs (n = 8; mean weight, 52.5 kg) were anticoagulated with warfarin (initial dose, 0.08 mg/kg) to a target prothrombin time (PT) of 30%-50% above baseline. A total of 15 histotripsy procedures were performed (kidney: n = 8, 2.0-cm sphere; liver: n = 7, 2.5-cm sphere). Treatments were immediately followed by computed tomography (CT) imaging. Animals were observed for 7 days while continuing anticoagulation, followed by repeat CT and necropsy., Results: All animals survived to complete the entire protocol with no signs of disability or distress. Three animals had hematuria (pink urine without clots). Baseline PT values (mean, 16.0 seconds) were elevated to 22.0 seconds (37.5% above baseline, P = .003) on the day of treatment and to 28.8 seconds (77.8% above baseline, P < .001) on the day of necropsy. At the time of treatment, 5 of 8 (63%) animals were at a therapeutic anticoagulation level, and all 8 animals (100%) reached therapeutic levels by the time of necropsy. There were no cases of intraparenchymal, peritoneal, or retroperitoneal hemorrhage associated with any treatments despite 5 of 7 (71%) liver and all 8 (100%) kidney treatments extending to the organ surface., Conclusions: Liver and kidney histotripsy seems safe with no elevated bleeding risk in this anticoagulated animal model, supporting the possibility of histotripsy treatments in patients on anticoagulation., (Copyright © 2022 SIR. Published by Elsevier Inc. All rights reserved.)

Patients with metastatic renal cell cancer (mRCC) who respond to upfront immune checkpoint inhibitor (ICI) combination therapies may be treated with cytoreductive nephrectomy (CN) to remove radiographically viable primary tumors. Early data for post-ICI CN suggested that ICI therapies induce desmoplastic reactions in some patients, increasing the risk of surgical complications and perioperative mortality. We evaluated perioperative outcomes for 75 consecutive patients treated with post-ICI CN at four institutions from 2017 to 2022. Our cohort of 75 patients had minimal or no residual metastatic disease but radiographically enhancing primary tumors after ICI and were treated with CN. Intraoperative complications were identified in 3/75 patients (4%) and 90-d postoperative complications in 19/75 (25%), including two patients (3%) with high-grade (Clavien ≥III) complications. One patient was readmitted within 30 d. No patients died within 90 d after surgery. Viable tumor was present in all but one specimen. Approximately half of the patients (36/75, 48%) remained off systemic therapy at last follow-up. These data suggest that CN following ICI therapy is safe and associated with low rates of major postoperative complications in appropriately selected patients at experienced centers. Post-ICI CN may facilitate observation without additional systemic therapy in patients without significant residual metastatic disease., Patient Summary: Current first-line treatment for patients with kidney cancer that has spread to other sites (metastatic cancer) is immunotherapy. For cases in which metastatic sites respond to this therapy but primary tumor is still detected in the kidney, surgical treatment of the tumor is feasible and has a low rate of complications, and may delay the need for further chemotherapy., (© 2023 The Author(s).)

Purpose: Liquid biopsies in metastatic renal cell carcinoma (mRCC) provide a unique approach to understand the molecular basis of treatment response and resistance. This is particularly important in the context of immunotherapies, which target key immune-tumor interactions. Unlike metastatic tissue biopsies, serial real-time profiling of mRCC is feasible with our noninvasive circulating tumor cell (CTC) approach., Methods: We collected 457 longitudinal liquid biopsies from 104 patients with mRCC enrolled in one of two studies, either a prospective cohort or a phase II multicenter adaptive immunotherapy trial. Using a novel CTC capture and automated microscopy platform, we profiled CTC enumeration and expression of HLA I and programmed cell death-ligand 1 (PD-L1). Given their diametric immunological roles, we focused on the HLA I to PD-L1 ratio (HP ratio)., Results: Patients with radiographic responses showed significantly lower CTC abundances throughout treatment. Furthermore, patients whose CTC enumeration trajectory was in the highest quartile (> 0.12 CTCs/mL annually) had shorter overall survival (median 17.0 months v 21.1 months, P < .001). Throughout treatment, the HP ratio decreased in patients receiving immunotherapy but not in patients receiving tyrosine kinase inhibitors. Patients with an HP ratio trajectory in the highest quartile (≥ 0.0012 annually) displayed significantly shorter overall survival (median 18.4 months v 21.2 months, P = .003)., Conclusion: In the first large longitudinal CTC study in mRCC to date to our knowledge, we identified the prognostic importance of CTC enumeration and the change over time of both CTC enumeration and the HP ratio. These insights into changes in both tumor burden and the molecular profile of tumor cells in response to different treatments provide potential biomarkers to predict and monitor response to immunotherapy in mRCC.

While an important role for the SUMO protease SENP1 is recognized in multiple solid cancers, its role in renal cell carcinoma (RCC) pathogenesis, particularly the most dominant subtype, clear cell RCC (ccRCC), is poorly understood. Here we show that a combination of high HIF2α and SENP1 expression in ccRCC samples predicts poor patient survival. Using ccRCC cell models that express high HIF2α but low SENP1, we show that overexpression of SENP1 reduces sumoylation and ubiquitination of HIF2α, increases HIF2α transcriptional activity, and enhances expression of genes associated with cancer cell invasion, stemness and epithelial-mesenchymal transition. Accordingly, ccRCC cells with high HIF2α and SENP1 showed increased invasion and sphere formation in vitro, and local invasion and metastasis in vivo. Finally, SENP1 overexpression caused high HIF2α ccRCC cells to acquire resistance to a clinical mTOR inhibitor, everolimus. These results reveal a combination of high SENP1 and HIF2α expression gives particularly poor prognosis for ccRCC patients and suggest that SENP1 may be an attractive new target for treating metastatic RCC (mRCC)., (© 2022. The Author(s).)

Objective: To evaluate the effect of intra-procedural contrast-enhanced CT (CECT) and same-session repeat ablation (SSRA) on primary efficacy, the complete eradication of tumor after the first ablation session as confirmed on first imaging follow-up, of clinically localized T1a (cT1a) renal cell carcinoma (RCC)., Methods: 398 consecutive patients with cT1a RCC were treated with cryoablation between 10/2003 and 12/2017, radiofrequency (RFA) or microwave ablation (MWA) between 1/2010 and 12/2017. SSRA was performed for residual tumor identified on intra-procedural CECT. Kruskal-Wallis and Pearson's chi-squared tests were performed to assess differences in continuous and categorical variables, respectively. Multivariate linear regression was used to determine predictors for primary efficacy and decline in estimated glomerular filtration rate., Results: 347 consecutive patients (231 M, mean age 67.5 ± 9.1 years) were included. Median tumor diameter was smaller [2.5 vs 2.7 vs 2.6 (p = 0.03)] and RENAL Nephrometry Score (NS) was lower [6 vs 7 vs 7 (p = 0.009] for MWA compared to the RFA and cryoablation cohorts, respectively. Primary efficacy was higher in the MWA cohort [99.4% (170/171)] compared to the RFA [91.4% (85/93)] and cryoablation [92.8% (77/83)] cohorts (p = 0.001). Microwave ablation and SSRA was associated with higher primary efficacy on multivariate linear regression (p = 0.01-0.03)., Conclusion: MWA augmented by SSRA, when residual tumor is identified on intra-procedural CECT, may improve primary efficacy for cT1a RCC., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Solid renal masses are often indeterminate for benignity versus malignancy on magnetic resonance imaging. Such masses are typically evaluated with either percutaneous biopsy or surgical resection. Percutaneous biopsy can be non-diagnostic and some surgically resected lesions are inadvertently benign., Purpose: To assess the performance of ten machine learning (ML) algorithms trained with MRI-based radiomics features in distinguishing benign from malignant solid renal masses., Methods: Patients with solid renal masses identified on pre-intervention MRI were curated from our institutional database. Masses with a definitive diagnosis via imaging (for angiomyolipomas) or via biopsy or surgical resection (for oncocytomas or renal cell carcinomas) were selected. Each mass was segmented for both T2- and post-contrast T1-weighted images. Radiomics features were derived from the segmented masses for each imaging sequence. Ten ML algorithms were trained with the radiomics features gleaned from each MR sequence, as well as the combination of MR sequences., Results: In total, 182 renal masses in 160 patients were included in the study. The support vector machine algorithm trained on radiomics features from T2-weighted images performed superiorly, with an accuracy of 0.80 and an area under the curve (AUC) of 0.79. Linear discriminant analysis (accuracy = 0.84 and AUC = 0.77) and logistic regression (accuracy = 0.78 and AUC = 0.78) algorithms trained on T2-based radiomics features performed similarly. ML algorithms trained on radiomics features from post-contrast T1-weighted images or the combination of radiomics features from T2- and post-contrast T1-weighted images yielded lower performance., Conclusion: Machine learning models trained with radiomics features derived from T2-weighted images can provide high accuracy for distinguishing benign from malignant solid renal masses., Clinical Impact: Machine learning models derived from MRI-based radiomics features may improve the clinical management of solid renal masses and have the potential to reduce the frequency with which benign solid renal masses are biopsied or surgically resected., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Modeling renal cell carcinoma is critical to investigating tumor biology and therapeutic mechanisms. Multiple systems have been developed to represent critical components of the tumor and its surrounding microenvironment. Prominent in vitro models include traditional cell cultures, 3D organoid models, and microphysiological devices. In vivo models consist of murine patient derived xenografts or genetically engineered mice. Each system has unique advantages as well as limitations and researchers must thoroughly understand each model to properly investigate research questions. This review addresses common model systems for renal cell carcinoma and critically evaluates their performance and ability to measure tumor characteristics., Competing Interests: DB holds equity in Bellbrook Labs LLC, Tasso Inc., Turba LLC, Salus Discovery LLC, Stacks to the Future LLC, Lynx Biosciences Inc., Flambeau Diagnostics, and Onexio Biosystems. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Shapiro, Virumbrales-Muñoz, Beebe and Abel.)

Renal cell carcinomas are common genitourinary tumors characterized by high vascularization and strong reliance on glycolysis. Despite the many available therapies for renal cell carcinomas, first-line targeted therapies, such as cabozantinib, and durable reaponses are seen in only a small percentage of patients. Yet, little is known about the mechanisms that drive response (or lack thereof). This dearth of knowledge can be explained by the dynamic and complex microenvironment of renal carcinoma, which remains challenging to recapitulate in vitro. Here, we present a microphysiological model of renal cell carcinoma, including a tubular blood vessel model of induced pluripotent stem cell-derived endothelial cells and an adjacent 3D carcinoma model. Our model recapitulated hypoxia, glycolic metabolism, and sprouting angiogenesis. Using our model, we showed that cabozantinib altered cancer cell metabolism and decreased sprouting angiogenesis but did not restore barrier function. This microphysiological model could be helpful to elucidate, through multiple endpoints, the contributions of the relevant environmental components in eliciting a functional response or resistance to therapy in renal cell carcinoma., (Copyright © 2022. Published by Elsevier Ltd.)

Purpose: Simple renal cysts are common benign lesions that arise from the renal parenchyma. Cyst growth can lead to confusion as well as concern from patients and referring providers about the need for imaging follow-up or additional evaluation. The purpose of this study was to evaluate the natural history of simple renal cysts and determine the best metric to characterize cyst evolution., Methods: 222 simple renal cysts in 182 adults (age = 58.4 ± 6.0 years) were longitudinally evaluated on non-contrast CT examinations over a mean interval of 7.5 ± 2.8 years. Axial long axis, surface area, and volume were evaluated at baseline and follow-up CT examinations. Absolute and percent annualized growth rates were computed between CT studies for each parameter., Results: At baseline CT examinations, mean (± SD) axial long axis, surface area, and volume measurements were 2.5 ± 1.7 cm, 2.5 ± 4.5 cm 2 , and 17.6 ± 52.5 ml, respectively. On follow-up examinations, measurements were 3.4 ± 2.0 cm, 4.2 ± 5.9 cm 2 , and 34.4 ± 92.3 ml, respectively. Significant differences (p < 0.01) were found between baseline and follow-up values for each parameter. The absolute growth rate of each parameter was + 0.1 ± 0.1 cm/year, + 2.1 ± 3.4 cm 2 /year, and + 2.0 ± 5.6 ml/year, respectively. The percent annualized growth rate for each parameter was +6.5 ± 7.3%/year, +18 ± 24%/year, and +46 ± 100%/year, respectively. Overall, 86% (190/222) of cysts increased in size over time; most notably 78% (174/222) increased by ≥ 6% in volume per year. None of the simple cysts developed septations or solid components on follow-up examinations., Conclusion: The majority of simple renal cysts increase in size over time, which was not associated with the development of complex features. Surface area and volume are the parameters most indicative of cyst growth or regression over time. In patients with enlarging asymptomatic simple renal cysts, no follow-up imaging is indicated., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Prostate cancer (PC) development involves epigenetic DNA methylation changes that occur in the tumor. However, distinct DNA methylation changes have been previously found to encompass a widespread cancer field defect involving normal prostate tissue. In the current study, we analyzed a series of DNA methylation field markers to determine if they predict the presence of PC in urine. Urine samples were collected from patients undergoing prostate biopsy with biopsy-proven PC (90), and without PC (77). From the urine pellet, methylated DNA was quantified across several previously identified CpG island regions near the caveolin 1 (CAV1), even-skipped homeobox 1 (EVX1), fibroblast growth factor 1 (FGF1), natural cytotoxicity triggering receptor 2 (NCR2) and phospholipase A and acyltransferase 3 (PLA2G16) genes using bisulfite pyrosequencing. Univariate and multivariate analyses were performed. Urine cell pellets show significant increases in methylation in four of the markers from patients with PC compared to those without PC including EVX1 12.2 vs. 7.7%, CAV1 15.7 vs. 10.36%, FGF1 12.0 vs. 7.1%, and PLA2G16 12.2 vs. 8.3% [all P<0.01]. Area under the ROC Curve (AUCs) were generated for EXV1 (0.74, Odds ratios (OR) 1.09; 95% confidence intervals (CI) 0.94-1.25, CAV1 (0.72, OR 1.18; 95% CI 1.09-1.28) and PLA2G16 (0.76, OR 1.35; 95% CI 1.199-1.51). In combination, a two-marker assay performs better than prostate specific antigen (PSA), AUC 0.77 vs. PSA AUC of 0.6 (P = 0.01) with the lowest error. In addition, FGF1 distinguished between grade group 1 (GG1) and higher grade cancers (P<0.03). In conclusion, applying methylation of field defect loci to urine samples provides a novel approach to distinguish patients with and without cancer., Competing Interests: A patent has been filed by the Wisconsin Alumni Research Foundation (WARF) regarding this technology., (AJCEU Copyright © 2021.)

Microwave (MW) ablation and stereotactic body radiation therapy (SBRT) are both used in treating inoperable renal cell carcinoma (RCC). MW ablation and SBRT have potentially complementary advantages and limitations. Combining SBRT and MW ablation may optimize tumor control and toxicity for patients with larger (> 5 cm) RCCs or those with vascular involvement. Seven patients with RCC were treated at our institution with combination of SBRT and MW ablation, median tumor size of 6.4 cm. Local control was 100% with a median follow-up of 15 months. Four patients experienced grade 2 nausea during SBRT. Three patients experienced toxicities after MW ablation, 2 with grade 1 hematuria and 1 with grade 3 retroperitoneal bleed/collecting system injury. Median eGFR (estimated glomerular filtration rate) preceding and following SBRT and MW ablation was 69 mL/min/1.73 m 2 and 68 mL/min/1.73 m 2 (P = .19), respectively. In patients who are not surgical candidates, larger RCCs or those with vascular invasion are challenging to treat. Combination treatment with SBRT and MW ablation may balance the risks and benefits of both therapies and demonstrates high local control in our series. MW ablation and SBRT have potentially complementary advantages and limitations., (Copyright © 2021. Published by Elsevier Inc.)

Objective: To interrogate the National Veterans Health Administration (VA) database to determine if beta-blocker use at time of initiation of androgen therapy deprivation (ADT) would result in improved oncological outcomes in advanced prostate cancer (PCa)., Methods: All men diagnosed with high risk PCa (PSA >20) from 2000-2008 who were on ADT ≥ 6 months were identified. Patients receiving ADT concurrently with primary radiation therapy were excluded. Pharmacy data was interrogated for all beta-blockers, but then focused on the selective beta-1 blocker metoprolol. Cox proportional hazards ratios were calculated for overall survival (OS), PCa specific survival (CSS) and skeletal related events (SREs)., Results: In 39,198 patients with high risk PCa on ADT, use of any beta-blocker was not associated with improvement in OS, CSS, or SREs. Further analyses focusing on metoprolol found that 10,224 (31.9%) had used metoprolol while 21,834 had no beta-blocker use. Multivariable analysis with Inverse Propensity Score Weighting, adjusted for factors including PSA, Gleason score, and duration ADT, found that utilization of metoprolol was not associated with improvement in OS (hazard ratio [HR] 0.97, P = .19), CSS (HR 0.94, P = .23) or SREs (HR 0.98, P = .79)., Conclusion: In this large cohort, metoprolol use in conjunction with ADT in high risk PCa was not associated with improvement in OS, CSS, or risk of SRE. In contrast to a recent smaller clinical study, our data strongly suggests no cancer specific benefit to beta-blocker use in advanced PCa., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Purpose: The purpose of this study was to evaluate the use of CT radiomics features and machine learning analysis to identify aggressive tumor features, including high nuclear grade (NG) and sarcomatoid (sarc) features, in large renal cell carcinomas (RCCs)., Methods: CT-based volumetric radiomics analysis was performed on non-contrast (NC) and portal venous (PV) phase multidetector computed tomography images of large (> 7 cm) untreated RCCs in 141 patients (46W/95M, mean age 60 years). Machine learning analysis was applied to the extracted radiomics data to evaluate for association with high NG (grade 3-4), with multichannel analysis for NG performed in a subset of patients (n = 80). A similar analysis was performed in a sarcomatoid rich cohort (n = 43, 31M/12F, mean age 63.7 years) using size-matched non-sarcomatoid controls (n = 49) for identification of sarcomatoid change., Results: The XG Boost Model performed best on the tested data. After manual and machine feature extraction, models consisted of 3, 7, 5, 10 radiomics features for NC sarc, PV sarc, NC NG and PV NG, respectively. The area under the receiver operating characteristic curve (AUC) for these models was 0.59, 0.65, 0.69 and 0.58 respectively. The multichannel NG model extracted 6 radiomic features using the feature selection strategy and showed an AUC of 0.67., Conclusions: Statistically significant but weak associations between aggressive tumor features (high nuclear grade, sarcomatoid features) in large RCC were identified using 3D radiomics and machine learning analysis., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Management options for small renal masses include active surveillance, partial nephrectomy, radical nephrectomy, and thermal ablation. For tumors typically ≤3 cm in size, thermal ablation is a good option for those desiring an alternative to surgery or active surveillance, especially in patients who are considered high surgical risk. We favor microwave ablation because of the more rapid heating, higher temperatures that overcome the heat sink effect of vessels, reproducible cell kill, and a highly visible ablation zone formed by water vapor that corresponds well to the zone of necrosis. For central tumors, we favor cryoablation because of the slower formation of the ablation zone and less likelihood of damage to the collecting system. With microwaves, it is important to monitor the ablation zone in real time (ultrasound is the best modality for this purpose), avoid direct punctures of the collecting system, and to place probes tangential to the collecting system to avoid burning open a persistent tract between the urothelium and extrarenal spaces or causing strictures. The surgical steps described in this video cover our use of high-frequency jet ventilation with general anesthesia to minimize organ motion, initial imaging and targeting, probe insertion, hydrodissection (a technique that enables displacement of adjacent structures), the ablation itself, and finally our dressing. Postoperative cares typically consist of observation with a same-day discharge or an overnight stay. Follow-up includes a magnetic resonance imaging abdomen with and without contrast, chest X-ray, and laboratories (basic metabolic panel, complete blood count, and C-reactive protein) 6 months postablation. Overall, percutaneous microwave ablation is an effective and safe treatment option for renal cell carcinoma in both T1a and T1b tumors in selected patients with multiple studies showing excellent oncologic outcomes when compared with partial and radical nephrectomy.

Objective: To evaluate the effect of intravenous iodinated contrast on estimated glomerular filtration rate (eGFR) when administered immediately after thermal ablation of clinically localized T1a (cT1a) renal cell carcinoma (RCC)., Methods: This HIPAA-compliant, dual-center retrospective study was performed under a waiver of informed consent. Three hundred forty-two consecutive patients with cT1a biopsy-proven RCC were treated with percutaneous ablation between January 2010 and December 2017. Immediate post-ablation contrast-enhanced CT was the routine standard of care at one institution (contrast group), but not the other (control group). One-month pre- and 6-month post-ablation eGFR were compared using the Wilcoxon signed-rank test or the Kruskal-Wallis test. Multivariate linear regression was used to determine the effect of contrast on eGFR. A 1:1 propensity score matching was performed for all patients with a logistic model using patient, tumor, and procedural covariates., Results: In total, 246 patients (158 M; median age 69 years, IQR 62-74) were included. Median tumor diameter (2.4 vs 2.5, p = 0.23) and RENAL nephrometry scores (6 vs 6, p = 0.92), surrogates for ablation zone size, were similar. Baseline kidney function was similar for the control and contrast groups, respectively (median eGFR: 70 vs 74 mL/min/1.73 m 2 , p = 0.29). There was an expected mild decline in eGFR after ablation (control: 70 vs 60 mL/min/1.73 m 2 , p < 0.001; contrast: 75 vs 71 mL/min/1.73 m 2 , p = 0.001). Intravenous iodinated contrast was not associated with a decline in eGFR on multivariate linear regression (1.91, 95% CI - 3.43-7.24, p = 0.46) or 1:1 propensity score-matched model (- 0.33, 95% CI - 6.81-6.15, p = 0.92)., Conclusion: Intravenous iodinated contrast administered during ablation of cT1a RCC has no effect on eGFR., Key Points: • Intravenous iodinated contrast administered during thermal ablation of clinically localized T1a renal cell carcinoma has no effect on kidney function. • Thermal ablation of clinically localized T1a renal cell carcinoma results in a mild decline in kidney function. • A decline in kidney function is similar for radiofrequency and microwave ablation of clinically localized T1a renal cell carcinoma., (© 2021. European Society of Radiology.)

OBJECTIVE. The purpose of this article is to evaluate interobserver, intraobserver, and interplatform variability and compare the previously established association between texture metrics and tumor histologic subtype using three commercially available CT texture analysis (CTTA) software platforms on the same dataset of large (> 7 cm) renal cell carcinomas (RCCs). MATERIALS AND METHODS. CT-based texture analysis was performed on contrast-enhanced MDCT images of large (> 7 cm) untreated RCCs in 124 patients (median age, 62 years; 82 men and 42 women) using three different software platforms. Using this previously studied cohort, texture features were compared across platforms. Features were correlated with histologic subtype, and strength of association was compared between platforms. Single-slice and volumetric measures from one platform were compared. Values for interobserver and intraobserver variability on a tumor subset ( n = 30) were assessed across platforms. RESULTS. Metrics including mean gray-level intensity, SD, and volume correlated fairly well across platforms (concordance correlation coefficient [CCC], 0.66-0.99; mean relative difference [MRD], 0.17-5.97%). Entropy showed high variability (CCC, 0.04; MRD, 44.5%). Mean, SD, mean of positive pixels (MPP), and entropy were associated with clear cell histologic subtype on almost all platforms ( p < .05). Mean, SD, entropy, and MPP were highly reproducible on most platforms on both interobserver and intraobserver analysis. CONCLUSION. Select texture metrics were reproducible across platforms and readers, but other metrics were widely variable. If clinical models are developed that use CTTA for medical decision making, these differences in reproducibility of some features across platforms need to be considered, and standardization is critical for more widespread adaptation and implementation.

Close to 74,000 cases of renal cell carcinoma (RCC) are diagnosed each year in the United States. The past 2 decades have shown great developments in surgical techniques, targeted therapy and immunotherapy agents, and longer complete response rates. However, without a global cure, there is still room for further advancement in improving patient care in this space. To address some of the gaps restricting this progress, the Kidney Cancer Association brought together a group of 27 specialists across the areas of clinical care, research, industry, and advocacy at the inaugural "Think Tank: Coalition for a Cure" session. Topics addressed included screening, imaging, rarer RCC subtypes, combination drug therapy options, and patient response. This commentary summarizes the discussion of these topics and their respective clinical challenges, along with a proposal of projects for collaboration in overcoming those needs and making a greater impact on care for patients with RCC moving forward., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: The decision to perform a partial nephrectomy (PN) relies largely upon the complexity of the renal mass and its surrounding anatomy. The presence of adherent perinephric fat (APF) can increase surgical complexity and extend operative times. The accurate prediction of APF may improve surgical planning and aid in decision making for the surgical approach., Objective: We sought to develop and externally validate a score that predicts APF based on preoperative clinical and radiological prognostic factors., Design, Setting, and Participants: We retrospectively analyzed 495 consecutive patients who underwent open or minimally invasive PN. APF was defined as the presence of "dense," "adherent," or "sticky" perinephric fat at the time of dissection by the surgeon, and this did not require subcapsular dissection. Additionally, we analyzed an independent cohort of 285 patients for external validation., Outcome Measurements and Statistical Analysis: A score model was developed using multivariate logistic regression analysis. Calibration of the fitted model was assessed graphically with a plot of the predicted versus the actual probability of APF, and discrimination was assessed by calculating the area under the receiver operating characteristic curve., Results and Limitations: Of the 495 patients, 95 (19%) had APF. Patients with APF had longer operative (p=0.02) and arterial clamp (p=0.01) times than non-APF patients. On multivariate analyses, diabetes mellitus (p=0.009), posterior perinephric fat thickness (p<0.001), and perinephric stranding (p<0.001) were predictors of encountering APF in PN. A risk score ranging from 0 to 4 was developed based on these three variables to predict APF. The scoring system demonstrated good discrimination of 0.82 and 0.84 for the development and external validation cohorts, respectively., Conclusions: The APF score can accurately predict the presence of APF in patients with a small renal mass who are planning to undergo PN. This score could aid in pre- and intraoperative planning and impact the surgical approach., Patient Summary: The presence of "sticky" fat surrounding the kidney in patients undergoing partial nephrectomy has previously been linked to longer operative times, intraoperative complications, and surgical conversion. In our study, we found that this feature is more often presented in patients with diabetes mellitus, and thicker and more inflammatory fat on renal imaging. Based on these findings, we developed a risk score that can accurately predict this feature before surgery, in order to improve surgical planning and better counsel the patients., (Copyright © 2019 European Association of Urology. Published by Elsevier B.V. All rights reserved.)

Objective: To evaluate postoperative recurrence patterns for high-risk nonmetastatic renal cell carcinoma (RCC) and to identify prognostic factors associated with site-specific metastatic recurrence using a multi-institutional contemporary cohort., Methods: Data for nonmetastatic ≥pT3a RCC patients treated with surgery at 4 independent centers was analyzed. Initial recurrence locations were identified, and imaging templates were defined by anatomic landmarks using radiologic definitions. Prognostic factors for site specific recurrence were evaluated with univariate and multivariable analyses., Results: A total of 1057 patients were treated surgically for ≥pT3a RCC. Initial recurrence location was in a single site for 160 (59.3%) patients and at multiple locations in 110 (41.7%) patients. The most common sites of metastatic recurrence were lung (144/270, 53.3%), liver (54/270, 20.0%), and bone (48/270, 17.8%). Recurrence was identified in 52 of 270 (19.3%) patients outside the chest/abdomen template, most commonly in the pelvis (25/270, 9.3%). Bone and brain metastases were the most common organs for metastases outside chest/abdomen. Patients with tumor diameter >10 cm and grade 4 were more likely to recur in the bone (HR 3.61, P <.001) and brain (HR 16.5, P <.001)., Conclusion: Metastatic progression outside chest/abdomen imaging templates was present in 1 of 5 high risk patients at initial metastatic RCC diagnosis, most commonly in the pelvis. Patients with large (>10 cm) tumors and grade 4 histology are at highest risk for bone and brain metastases., (Copyright © 2020. Published by Elsevier Inc.)

Clear cell renal cell carcinoma (ccRCC) is a common genitourinary cancer associated with the development of abnormal tumor angiogenesis. Although multiple anti-angiogenic therapies have been developed, responses to individual treatment are highly variable between patients. Thus, the use of one-patient clinical trials has been suggested as an alternative to standard trials. We used a microfluidic device to generate organotypic primary patient-specific blood vessel models using normal (NEnC) and tumor-associated primary CD31+ selected cells (TEnC). Our model was able to recapitulate differences in angiogenic sprouting and vessel permeability that characterize normal and tumor-associated vessels. We analyzed the expression profile of vessel models to define vascular normalization in a patient-specific manner. Using this data, we identified actionable targets to normalize TEnC vessel function to a more NEnC-like phenotype. Finally, we tested two of these drugs in our patient-specific models to determine the efficiency in restoring vessel function showing the potential of the model for single-patient clinical trials.

Objective: To describe the CT and MR imaging findings after microwave ablation of clinical stage 1 renal cell carcinoma (RCC)., Methods: This single-center retrospective study was performed under a waiver of informed consent. 49 patients (38 M/11F, mean age 66 ± 9.0) with 52 cT1a RCC and 19 patients (10M/9F, mean age 67 ± 9.7) with 19 cT1b RCC were treated with percutaneous microwave ablation between January 2012 and June 2014. The size and volume of the RCC and ablation zone were measured and the kidney, ablation zones and retroperitoneum were assessed at immediate post-procedure CT and surveillance CT and MRI., Results: Median imaging follow-up was 18 months (IQR 12-28). Ablation zones were heterogeneously hyperintense on T1W and hypointense on T2W MRI and hyperdense at CT. Thin peripheral, but no internal enhancement after contrast administration signified successful ablation zones. Ablation zones decreased in size, but did not resolve during surveillance. Immediate post-procedure subcapsular gas and hematoma (5/71, 7%) resolved prior to first follow-up. Focal, enhancing soft tissue within the ablation zone, invariably along the renal margin, signified local recurrence. Local recurrence rates were higher for T1b (2/19, 11%) compared to T1a (1/52, 2%). Urinomas (4/71, 6%) decreased in size and resolved during surveillance. Retroperitoneal fat necrosis (6/71, 9%), with opposed-phase loss of T1W MRI signal, was confirmed at histology after percutaneous biopsy., Conclusion: CT and MR imaging features after microwave ablation of renal cell carcinoma are predictable and reliably demonstrate treatment success, early and delayed complications, and local recurrences that can guide patient management.

Purpose: Evaluate the safety and efficacy of adrenal microwave ablation performed with continuous intra-arterial blood pressure monitoring (IABPM) and without alpha-adrenergic blockade (AAB) as pretreatment., Material and Methods: A single-center, retrospective review of all percutaneous adrenal microwave ablation performed between 2011 and 2018. Microwave ablation was completed on 11 patients, with a total of 15 adrenal tumors with a mean size of 3.3 cm (1.4-6.9 cm) treated metastatic RCC, HCC, esophageal carcinoma, adrenal adenoma. Cases were performed without prior AAB, but with continuous IABPM and rapid intervention using short-acting antihypertensive medications., Results: There were no post-procedural episodes of hypertension, no neurological or cardiovascular complications, and no SIR moderate or worse adverse event complications. Mean intraprocedural maximum systolic blood pressure (SBP) was 211 mmHg (range: 132-288), with an average increase in SBP of 100 mmHg (range: 23-180). A hypertensive crisis (SBP ≥ 180 and/or DBP ≥ 120) occurred in 9 of the 15 procedures (60%) with a mean length of 3.0 min (range: 1-12). The technical success rate was 100% (15/15 procedures). The mean follow-up time was 2.4 years (range: 0.9-7.7 years), with primary and secondary efficacy rates of 77% and 87%, respectively, and an overall survival of 82%., Conclusion: In this single-center retrospective study, microwave ablation of adrenal tumors without AAB was safe and effective when performed with continuous arterial line monitoring of vital signs and the use of short-acting, rapid-onset antihypertensive medications., Level of Evidence: Level 4, Case Series.

Surgical metastasectomy continues to be utilized for patients with solitary or low-volume metastatic renal cell carcinoma (mRCC). Although few high-quality data are available to evaluate outcomes, local treatment is recommended when feasible because it may allow a subset of patients to delay or avoid systemic treatments. With the development of improved mRCC therapies, utilization of metastasectomy has increased because most patients have incomplete responses to systemic treatment of their metastases. This review discusses the rationale and history of metastasectomy, trends in utilization, prognostic factors for patient selection, site-specific considerations, alternatives for nonsurgical local treatment, and risk of morbidity associated with metastasectomy., Competing Interests: Conflicts of interest The authors have nothing to disclose., (Published by Elsevier Inc.)

Epidural anesthesia is used to improve pain control after major surgeries. Few data describe the impact of epidural use for bladder cancer patients treated with radical cystectomy (RC). Here, we evaluate epidural use on perioperative and long-term outcomes for patients treated with radical cystectomy for bladder cancer. Patients who received radical cystectomy for non-metastatic bladder urothelial carcinoma with epidural (n=1,748) and without epidural (n=6,109) anesthesia from 2002-2014 were identified using Surveillance, Epidemiology and End Results-Medicare data. Radical cystectomy outcomes with and without epidural anesthesia were compared using propensity score weighting. Epidural use at time of radical cystectomy was identified in 1,748 (22.2%) of 7,857 patients who met inclusion criteria. After propensity score weighted adjustment, epidural use was associated with increased 30-day readmission (29.6% vs. 26.2%, P<0.001), increased median length of stay in days (9.0, IQR 7.0-12.0 vs 8.0, IQR 6.0-12.0, P<0.01), and decreased likelihood of being discharged directly to home without need for home health or skilled nursing care (21.6% vs 29.1%, P<0.001). Post-operative MI (2.6% vs 1.3%, P<0.001) in the first 30 days after radical cystectomy was more common in the epidural group, but perioperative 30-day mortality was similar (3.3% vs 2.9%, P=0.21). Epidural use was not associated with increased cancer specific (HR 0.96, 0.90-1.02, P=0.20) or overall survival (HR 0.99, 0.95-1.04, P=0.73). Epidural use at time of radical cystectomy is associated with increased risk of perioperative complications, hospital readmission, and longer hospitalization without improving disease specific survival. Prospective studies are needed to confirm these findings., Competing Interests: None., (AJCEU Copyright © 2020.)

Background: The neutrophil-lymphocyte ratio (NLR) is an established signature of inflammation used for evaluating renal cell carcinoma (RCC)., Objective: To determine the utility of NLR and its relationship with known risk factors associated with poor survival in patients with metastatic RCC and tumor thrombus undergoing cytoreductive nephrectomy (CN)., Design, Setting, and Participants: Prognostic variables were reviewed for patients undergoing CN with thrombectomy between 2000 and 2014 from six different institutions. Patients were stratified for NLR >4.0 based on cut point analysis., Outcome Measurements and Statistical Analysis: Kaplan-Meier curves compared overall survival of the total cohort and established risk models (Memorial Sloan Kettering Cancer Center [MSKCC], International Metastatic Renal-Cell Carcinoma Database Consortium [IMDC], and M.D. Anderson Cancer Center [MDACC]) stratified by NLR. Multivariable Cox regression determined predictors of overall survival. Receiver operator characteristic curves tested the predictive accuracy of survival ≥12 mo, and area under the curve (AUC) was compared between models., Results and Limitations: In total, 332 patients were identified. Patients with NLR ≤4.0 had longer median survival (24.7 vs 15.2 mo, p=0.004). NLR >4.0 distinguished patients with significantly shorter survival for non-poor-risk groups defined by MSKCC, IMDC, and MDACC criteria. Systemic symptoms, low hemoglobin, elevated lactate dehydrogenase, retroperitoneal adenopathy, level IV thrombus, elevated absolute neutrophil count, and NLR >4 were independent predictors of decreased survival (p<0.05). These factors had higher predictive accuracy for survival at 12 mo (AUC=0.755) than MKSCC, IMDC, and MSKCC models., Conclusions: NLR >4.0 independently predicts poor survival and further distinguishes established risk model survival curves. We identified seven preoperative risk factors related to poor survival for patients with metastatic RCC with tumor thrombus undergoing CN., Patient Summary: The neutrophil-lymphocyte ratio and six additional preoperative variables can be used to better council patients regarding survival after surgery for metastatic renal cell carcinoma with tumor thrombus., (Copyright © 2018 European Association of Urology. Published by Elsevier B.V. All rights reserved.)

Objective: To compare perioperative and oncologic outcomes for patients with clinical T1b renal cell carcinoma following treatment with microwave ablation (MW), partial nephrectomy (PN), or radical nephrectomy (RN)., Methods: Comprehensive clinical and pathologic data were collected for nonmetastatic renal cell carcinoma patients with cT1b tumors following MW, PN, or RN from 2000 to 2018. Local recurrence-free, metastasis-free, cancer-specific and overall survival were estimated using Kaplan-Meier method. Prognostic factors for complications and survival were determined using logistic regression and Cox hazard models, respectively., Results: A total of 325 patients (40 MW, 74 PN, and 211 RN) were identified. Patients treated with MW were older with higher Charlson comorbidity indices compared to surgical patients. Median length of hospitalization was shorter for MW compared to surgical patients (1 day vs 4 days, P <.0001). Post-treatment estimated glomerular filtration rate decreased by median 4.5% for MW compared to 3.2% for PN (P = .58) and 29% for RN (P <.001). Median follow-up was 34, 35, and 49 months following MW, PN, and RN, respectively. Estimated 5-year local recurrence-free survival was 94.5% for MW vs 97.9% for PN (P = .34) and 99.2% for RN (P = .02). Two patients recurred after MW and underwent repeat ablation without subsequent recurrence. No difference in 5-year metastasis-free survival or cancer-specific survival was found among MW, PN, or RN. Four (10%) MW patients had high-grade complication. Only prior abdominal surgery predicted high-grade complication (OR 6.29, P = .017)., Conclusion: Microwave ablation is a feasible alternative to surgery in select comorbid patients with clinical T1b renal cell carcinoma., (Copyright © 2019. Published by Elsevier Inc.)

Penile amputation is a rare injury with significant posttraumatic ramifications. We present a case of successful immediate replantation after traumatic penile avulsion in a 52-year-old male patient. The patient reported his penis was caught in machinery during a boating accident, and avulsed at the level of the pubis. Immediate replantation of this proximal avulsion injury with no suitable proximal arterial stumps required transfer of the superficial inferior epigastric artery for arterial inflow. One artery and two veins were repaired. The urethral injury was found to be immediately distal to the urethral sphincter in the membranous portion, and repaired primarily. Urinary diversion was performed with a suprapubic catheter until the repair had healed. The postoperative course was complicated by less than 10% skin necrosis requiring skin grafting. At three years follow up, the patient has a penis with normal urinary function and is able to obtain erections with pharmacologic aids. Avulsion should not preclude penile replantation, which may have acceptable functional and esthetic results., (© 2019 Wiley Periodicals, Inc.)

OBJECTIVE. The purpose of this study was to evaluate the utility of CT texture analysis (CTTA) in differentiating low-attenuation renal cell carcinoma (RCC) from renal cysts on unenhanced CT. MATERIALS AND METHODS. Ninety-four patients with low-attenuation RCC on unenhanced CT were compared with a cohort of 192 patients with benign renal cysts. CT characteristics (size and minimum, maximum, and mean attenuation) and CTTA features were recorded using an ROI approximately two-thirds the size of the mass. Masses were subjectively assessed by two expert genitourinary readers and two novice readers using a 5-point Likert scale (1 = definite cyst, 5 = definite renal cell carcinoma). Results of first-order CTTA and subjective evaluation were compared using ROC analysis. RESULTS. The group of 94 patients with low-attenuation RCC included 62 men and 32 women (mean age, 58.0 years). On unenhanced CT, the RCC were larger than 10 mm and of a median size of 50 mm with less than or equal to 20 HU (mean attenuation, 16 ± 4 HU). Of the RCC cohort, 83 were clear cell subtype. The cohort of 192 patients included 134 men and 58 women (mean age, 64.7 years) with benign renal cysts greater than 10 mm and a median size of 27 mm and less than or equal to 20 HU (mean attenuation, 9 ± 6 HU). The mean follow-up time was 6.2 years. Mean entropy in the low-attenuation RCC group (4.1 ± 0.7) was significantly higher than in the cyst group (2.8 ± 1.3, p < 0.0001). Entropy showed an ROC AUC of 0.89, with sensitivity of 84% and specificity of 80% at threshold 3.9. The AUC was better than subjective evaluation by novice readers (AUC, 0.77) and comparable to subjective evaluation by two expert readers (AUC, 0.90). A model combining the three best texture features (unfiltered mean gray-level attenuation, coarse entropy, and kurtosis) showed an improved AUC of 0.92. CONCLUSION. High entropy revealed with CTTA may be used to differentiate low-attenuation RCC from cysts at unenhanced CT; this technique performs as well as expert readers.

Objective: To analyze risk factors and patterns of RCC recurrence following percutaneous ablation for stage 1 tumors and develop risk-stratified follow-up imaging protocols., Method: Biopsy-proven sporadic stage 1 RCC patients treated with percutaneous microwave ablation (MWA) or cryoablation (CA) from 2002 to 2017 were included. Kaplan-Meier analysis was used to estimate local and distant recurrence-free survival, cancer-specific survival and metastatic-free survival. Multivariable models were used to identify risk factors associated with recurrence., Results: A total of 256 patients with stage 1 RCC (215 T1a, 41 T1b) were treated with percutaneous MWA (178 subjects) or CA (78 subjects). Recurrence was identified in 23 patients (16 local, 7 distant). Clinical T stage (HR 2.46, 95% CI 1.06-5.72, P = .04) and tumor grade (HR 4.17, 95% CI 1.17-14.76, P = .03) were independent predictors of recurrence. Recurrence was not associated with Nephrometry score, cystic tumors, ablation modality (CA vs MWA) or gender. Five-year cancer-specific survival, and metastatic-free survival were 98.6% and 97.4%, respectively. Patients were stratified into 2 groups: reduced risk stage 1 (no risk factors) or elevated risk stage 1 (≥1 risk factor). Recurrence risk was higher in the elevated-risk group (HR = 3.19, 95% CI 1.35-7.53, P = .008). Five-year overall recurrence-free survival (local + distant) was higher in reduced-risk vs elevated-risk cohorts, 88% vs 69%, P = .005., Conclusion: High nuclear grade or T1b tumors have increased recurrence risk following percutaneous thermal ablation for stage 1 RCC. Current postablation follow-up protocols may be modified for individual recurrence risk to allow more frequent imaging for elevated-risk patients, while enabling less frequent imaging for reduced-risk patients., (Copyright © 2019. Published by Elsevier Inc.)

Introduction: Oncocytic neoplasms are renal tumors similar to oncocytoma, but their morphologic variations preclude definitive diagnosis. This somewhat confusing diagnosis can create treatment and surveillance challenges for the treating urologist. We hypothesize that these subtle morphologic variations do not drastically affect the malignant potential of these tumors, and we sought to demonstrate this by comparing clinical outcomes of oncocytic neoplasms to those of classic oncocytoma and chromophobe., Methods: We gathered demographic and outcomes data for patients with variant oncocytic tumors. Oncologic surveillance was conducted per institutional protocol in accordance with NCCN guidelines. Descriptive statistics were used to compare incidence of metastasis and death against those for patients with oncocytoma and chromophobe. Three hundred and fifty-one patients were analyzed: 164 patients with oncocytoma, 28 with oncocytic neoplasms, and 159 with chromophobe tumors., Results: Median follow-up time for the entire cohort was 32.4 months, (interquartile range 9.2-70.0). Seventeen total patients (17/351, 4.9%) died during the course of the study. In patients with oncocytoma or oncocytic neoplasm, none were known to metastasize or die of their disease. Only chromophobe tumors >6 cm in size in our series demonstrated metastatic progression and approximately half of these metastasized tumors demonstrated sarcomatoid changes., Conclusion: Variant oncocytic neoplasms appear to have a natural course similar to classic oncocytoma. These tumors appear to have no metastatic potential, and oncologic surveillance may not be indicated after surgery., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objective: To evaluate the impact of anterior tumor location on oncologic efficacy, complication rates, and procedure duration for 151 consecutive biopsy-proven clinical T1a renal cell carcinoma (RCC) treated with percutaneous microwave (MW) ablation., Methods: This single-center retrospective study was performed under a waiver of informed consent. One hundred forty-eight consecutive patients (103 M/45 F; median age 67 years, IQR 61-73) with 151 cT1a biopsy-proven RCC (median diameter 2.4 cm, IQR 1.9-3.0) were treated with percutaneous MW ablation between March 2011 and August 2017. Patient and procedural data collected included Charlson comorbidity index (CCI), RENAL nephrometry score (NS), use of hydrodisplacement, MW antennas/generator output/time, and procedure time (PT). Data were stratified by anterior, posterior, and midline tumor location and compared with the Kruskal-Wallis or chi-squared tests. The Kaplan-Meier method was used for survival analyses., Results: Tumor size, NS, and use/volume of hydrodisplacement were similar for posterior and anterior tumors (p > 0.05). Patients with anterior tumors had a higher CCI (3 vs 4, p = 0.001). Median PT for posterior and anterior tumors was similar (100 vs 108 min, p = 0.26). Single session technical success and primary efficacy were achieved for all 151 tumors including 61 posterior and 67 anterior tumors. The 4 (3%) Clavien III-IV complications and 6 (4%) local recurrences were not associated with tumor location (p > 0.05). Three-year RFS, CSS, and OS were 95% (95% CI 0.87, 0.98), 100% (95% CI 1.0, 1.0), and 96% (95% CI 0.89, 0.98), respectively., Conclusions: The safety and efficacy of percutaneous microwave ablation for anterior and posterior RCC are similar., Key Points: • The safety profile for percutaneous microwave ablation of anterior and posterior T1a renal cell carcinoma is equivalent. • Percutaneous microwave ablation of T1a renal cell carcinoma provides durable oncologic control regardless of tumor location. • Placement of additional microwave antennas and use of hydrodisplacement are associated with longer procedure times.