Treatment Of Small Renal Masses Research Articles

Clinical safety and efficacy of microwave ablation for small renal masses.

CT-guided MWA is a safe and effective tool that should be utilized in the treatment of small renal masses (SRMs). We aim to clarify the utility of CT-guided MWA by examining patient outcomes such as recurrence, treatment success, changes in renal function, and complications. A retrospective review of consecutive patients with SRMs who underwent same day renal mass biopsy (RMB) and CT-guided MWA between 2015 and 2022 was performed. Treatment safety was assessed by 30-day complications according to the Clavien-Dindo system and change in eGFR >30 days post-procedure. Treatment efficacy was defined by local recurrence and incomplete treatment rates and calculated using the Kaplan-Meier method. A total of 108 renal masses were found in 104 patients. The overall complication rate was 7.4% (8/108), of which 4 were major complications (3.7%). For those with renal function available >30 days post ablation, the median eGFR was 47.2 (IQR: 36.0, 57), compared to 52.3 (IQR: 43.7, 61.5) pre-ablation, p<0.0001. 5-year local recurrence free survival was 86%. Among those with biopsy proven malignancy (n= 66), there were five local recurrences (7.54%) occurring at a median of 25.1 months (IQR 19.9, 36.2) and one case (1.5%) of incomplete treatment. As the medical field continues to evolve towards less invasive interventions, MWA offers a valuable tool in the management of renal masses. With low major complication and recurrence rates, our findings support the utility of CT-guided MWA as a tool for treatment of SRMs.

Conversion to Radical Nephrectomy From Robotic Partial Nephrectomy Is Most Commonly Due to Anatomic and Oncologic Complexity.

Partial nephrectomy is standard-of-care treatment for small renal masses. As utilization of partial nephrectomy increases and includes larger and complex tumors, the risk of conversion to radical nephrectomy likely increases. We evaluated incidence and reason for conversion to radical nephrectomy in patients scheduled for partial nephrectomy by surgeons participating in MUSIC (the Michigan Urologic Surgery Improvement Collaborative). All patients in whom robotic partial nephrectomy was planned were stratified by completed procedure (robotic partial nephrectomy vs radical nephrectomy). Preoperative and intraoperative records were reviewed for preoperative assessment of difficulty and reason for conversion. Patient, tumor, pathologic, and practice variables were compared between cohorts. Of 650 patients scheduled for robotic partial nephrectomy, conversion to radical nephrectomy occurred in 27 (4.2%) patients. No conversions to open were reported. Preoperative documentation indicated a plan for possible conversion in 18 (67%) patients including partial with possible radical (n = 8), partial vs radical (n = 6), or likely radical nephrectomy (n = 4). Intraoperative documentation indicated that only 5 (19%) conversions were secondary to bleeding, with the remaining conversions due to tumor complexity and/or oncologic concerns. Patients undergoing conversion had larger (4.7 vs 2.8 cm, P < .001) and higher-complexity tumors (64% vs 6%, P < .001) with R.E.N.A.L. (for radius, exophytic/endophytic, nearness of tumor to collecting system, anterior/posterior, location relative to polar line) nephrometry score ≥ 10. The converted cases had a higher rate of ≥ pT3 (27% vs 8.4%, P = .008). There was a low rate of conversion from robotic partial to radical nephrectomy in the MUSIC-KIDNEY (Kidney mass: Identifying and Defining Necessary Evaluation and therapY) collaborative, and an even lower risk of conversion due to uncontrolled bleeding. Targeted review of each conversion identified appropriate decision-making based on oncologic risk in most cases.

Image-Guided Ablation of Renal Masses: Challenges to Produce High-Quality Evidence and Future Directions.

Image-guided ablation (IGA) is a rapidly developing field in interventional oncology. There is some evidence suggesting IGA's non-inferiority compared with partial or radical nephrectomy for the treatment of small renal masses (SRM). However, these are mostly limited to retrospective cohort studies. This review article outlines the evidence comparing IGA to partial nephrectomy by collating the different survival measures and evaluates the challenges of producing clinical trials and high-quality evidence. The main challenges are due to the heterogeneity of SRM, patient selection bias, unstandardized endpoint and outcomes, and the lack of global practice standards. Despite the evidence thus far demonstrating that IGA stands as a non-inferior treatment modality for SRMs, exhibiting favorable short- and long-term outcomes, further robust research is needed to integrate ablation techniques into routine clinical practice with a multidisciplinary approach. There is emerging evidence that suggests randomized controlled trial in SRMs is possible, and technologies such as histotripsy as well as artificial intelligence are used in IGA.

Ablative Treatments for Small Renal Masses and Management of Recurrences: A Comprehensive Review.

This review focuses on ablative techniques for small renal masses (SRMs), including radiofrequency ablation (RFA), cryoablation (CA), microwave ablation (MWA), and irreversible electroporation (IRE), and discusses recurrence management. Through an extensive literature review, we outline the procedures, outcomes, and follow-up strategies associated with each ablative method. The review provides a detailed examination of these techniques-RFA, CA, MWA, and IRE-elucidating their respective outcomes. Recurrence rates vary among them, with RFA and CA showing comparable rates, MWA demonstrating favorable short-term results, and IRE exhibiting promise in experimental stages. For managing recurrences, various strategies are considered, including active surveillance, re-ablation, or salvage surgery. Surveillance is preferred post-RFA and post-CA, due to slow SRM growth, while re-ablation, particularly with RFA and CA, is deemed feasible without additional complications. Salvage surgery emerges as a viable option for larger or resistant tumors. While ablative techniques offer short-term results comparable to surgery, further research is essential to understand their long-term effects fully. Decisions concerning recurrence management should consider individual and tumor-specific factors. Imaging, notably contrast-enhanced ultrasounds, plays a pivotal role in assessing treatment success, emphasizing the necessity of a multidisciplinary approach for optimal outcomes. The lack of randomized trials highlights the need for further research.

Usefulness of renal nephrometry scoring systems in the prediction of complications associated to percutaneous image-guided treatment for small renal masses

IntroductionDue to their increasing prevalence and complex management, renal tumors are challenging for health professionals. The study aims to evaluate the usefulness of R.E.N.A.L. and PADUA nephrometry scores in the prediction of complications after percutaneous cryoablation. Material and methodsThe study prospectively analyzed 90 patients with 101 stage T1a renal cell carcinoma (RCC) tumors treated with cryoablation. ResultsNinety patients with 101 small renal tumors who received cryoablative therapy were investigated. The mean age of the patients was 68 years and 74.4% were male. Most tumors were smaller than 4 cm (89.1%) and the mean PADUA and R.E.N.A.L. scores were 8.65 and 7.35, respectively. Complications were observed in 12 cases. PADUA and R.E.N.A.L. scores demonstrated moderate predictive power (AUC = 0.58 and AUC = 0.63, respectively) for post-cryoablation complications. ConclusionsPercutaneous cryoablation is a safe and effective treatment for small renal tumors. The R.E.N.A.L. and PADUA renal nephrometry scores have moderate predictive power for complications associated with percutaneous cryoablation of renal tumors.

Percutaneous tumor ablation versus image guided robotic-assisted partial nephrectomy for cT1b renal cell carcinoma: a comparative matched-pair analysis (UroCCR 80).

Partial nephrectomy (PN) is the gold standard treatment for cT1b renal tumors. Percutaneous guided thermal ablation (TA) has proven oncologic efficacy with low morbidity for the treatment of small renal masses (<3 cm). Recently, 3D image-guided robot-assisted PN (3D-IGRAPN) has been described, and decreased perioperative morbidity compared to standard RAPN has been reported. Our objective was to compare two minimally invasive image-guided nephron-sparing procedures (TA vs. 3D-IGRAPN) for the treatment of cT1b renal cell carcinomas (4.1-7 cm). Patients treated with TA and 3D-IGRAPN for cT1b renal cell carcinoma, prospectively included in the UroCCR database (NCT03293563), were pair-matched for tumor size, pathology, and RENAL score. The primary endpoint was the local recurrence rate between the two groups. Secondary endpoints included metastatic evolution, perioperative complications, decrease in renal function, and length of hospitalization. A total of 198 patients were included and matched into two groups of 72 patients. The local recurrence rate was significantly higher in the TA group than that in the 3D-IGRAPN group (4.2% vs. 15.2%, P=0.04). Metastatic evolution and perioperative outcomes such as major complications, eGFR decrease, and length of hospitalization did not differ significantly between the two groups. 3D-IGRAPN resulted in a significantly lower local recurrence rate and comparable rates of complications and metastatic evolution compared with thermal ablation.

PE060 - Minimal surgical impact robotic-assisted partial nephrectomy for the treatment of small renal masses: The role of 3D models in the preoperative planning

PE060 - Minimal surgical impact robotic-assisted partial nephrectomy for the treatment of small renal masses: The role of 3D models in the preoperative planning

VE59 - Robotic-assisted partial nephrectomy with minimal surgical impact after 3D virtual planning for the treatment of small renal masses

VE59 - Robotic-assisted partial nephrectomy with minimal surgical impact after 3D virtual planning for the treatment of small renal masses

The role of three-dimensional virtual models to plan a minimal surgical impact robot assisted partial nephrectomy for the treatment of small renal masses

The role of three-dimensional virtual models to plan a minimal surgical impact robot assisted partial nephrectomy for the treatment of small renal masses

Radiofrequency Ablation, Cryoablation, and Microwave Ablation for the Treatment of Small Renal Masses: Efficacy and Complications.

Over the last two decades the detection rate of small renal masses has increased, due to improving diagnostic accuracy, and nephron-sparing treatments have become the first-choice curative option for small renal masses. As a minimally invasive alternative, thermal ablation has increased in popularity, offering a good clinical outcome and low recurrence rate. Radiofrequency ablation, Cryoablation, and Microwave ablation are the main ablative techniques. All of them are mostly overlapping in term of cancer specific free survival and outcomes. These techniques require imaging study to assess lesions features and to plan the procedure: US, CT, and both of them together are the leading guidance alternatives. Imaging findings guide the interventional radiologist in assessing the risk of complication and possible residual disease after procedure. The purpose of this review is to compare different ablative modalities and different imaging guides, underlining the effectiveness, outcomes, and complications related to each of them, in order to assist the interventional radiologist in choosing the best option for the patient.

SHORT-TERM OUTCOMES OF PERCUTANEOUS RADIOFREQUENCY AND MICROWAVE ABLATION IN THE TREATMENT OF SMALL RENAL MASSES.

Although the gold standard in the management of kidney tumors is surgical treatment, thermal ablation methods are a viable therapeutic option for patients with small (<4 cm) renal masses who are poor surgical candidates. The aim of this study was to compare the technical success, primary efficacy and complication rate of percutaneous radiofrequency and microwave ablation in the treatment of small renal masses. A retrospective analysis of consecutive patients with small renal masses treated with radiofrequency or microwave ablation between December 2017 and January 2022 was conducted. Response to the ablative therapy was assessed on contrast-enhanced computed tomography examination after 3 months. Ablations of 44 kidney lesions were performed in 43 patients. Sixteen lesions were treated with radiofrequency and 28 with microwave ablation. Both methods were associated with high technical success (100%). Primary efficacy rates of radiofrequency and microwave ablation were 81.3% and 89.3%, respectively. Ablation-related complications were noted only in the patients treated with microwave ablation (18.5%), all of them being low grade (Clavien-Dindo 1 and 2). Radiofrequency and microwave ablation exhibited comparable efficacy in the treatment of small renal masses. Microwave ablation was associated with a comparatively higher number of complications.

Cryoablation for the management of Small Renal Masses

Renal cell carcinoma is identified most often in the sixth or seventh decade of life, coinciding with the rise in incidental diagnosis of small renal masses as imaging technology has advanced. However, not all patients in this older age group are surgical candidates owing to their comorbidities. Cryoablation is a well-established minimally invasive technique for the treatment of small renal masses. The advent of less invasive ablative treatment has alleviated the surgical dilemma for certain patients who are contraindicated for extirpative procedures. With the appropriate patient selection, cryoablation is safe and effective, resulting in comparable local tumor control, fewer complications, better preservation of renal function, a faster recovery, and a shorter hospital stay. The percutaneous procedure has increased in popularity due to the advantages of reduced pain, shorter hospitalization, the ability to be performed without general anesthesia, and decreased cost relative to surgery.

Microwave versus cryoablation and radiofrequency ablation for small renal mass: a multicenter comparative analysis.

Ablative techniques emerged as effective alternative to nephron-sparing surgery for treatment of small renal masses. Radiofrequency ablation (RFA) and cryoablation (CRYO) are the two guidelines-recommended techniques. Microwave ablation (MWA) represents a newer technology, less described. The aim of the study was to compare outcomes of MWA to those of CRYO and RFA. Retrospective investigation of patients who underwent MWA, CRYO, or RFA from seven high-volume US and European centers was performed. The first group included patients who underwent CRYO or RFA; the second MWA. We collected baseline characteristics, clinical, intraoperative, and postoperative data. Oncological data included technical success, local recurrence, and progression to metastasis. Multivariate analysis was performed to find predictors for postoperative complications. A composite outcome of "trifecta" was used to assess surgical, functional, and oncological outcomes. 739 patients underwent CRYO or RFA and 50 MWA. CRYO/RFA group had significantly longer operative time (P<0.001), but no difference in LOS, postprocedural Hb mean, intraprocedural complications (P=0.180), overall postprocedural complication rates (P=0.126), and in the 30-day re-admission rate (P=0.853) were detected. No predictive parameter of postprocedural complications was found. Concerning functional outcome, no differences were detected in terms of eGFR at 1 year (P=0.182), ΔeGFR at 1 year (P=0.825) and eGFR at latest follow-up (P=0.070). "Technical success" was achieved in 98.6% of the cases (MWA=100%, CRYO/RFA=98.5%; P=0.775), and there was no significant difference in terms of 2-year recurrence rate (P=0.114) and metastatic progression (P=0.203). Trifecta was achieved in 73.0% of CRYO/RFA vs. 69.6% of MWA cases (P=0.719). MWA is a safe and effective treatment option for small renal masses. Compared with CRYO/RFA, it seems to offer low complication rates, shorter operation time, and equivalent surgical and functional outcomes.

Cost Implications of Routine Preoperative Blood Typing and Crossmatching Prior to Robot-Assisted Laparoscopic Partial Nephrectomy.

The surgical treatment of small renal masses has shifted from open to minimally invasive approaches. Preoperative blood typing and product orders often mirror the practices of the open era. We aim to define the rate of transfusion after robot-assisted partial laparoscopic nephrectomy (RAPN) at an academic medical center and the costs associated with current practice. A retrospective review of an institutional database was utilized to identify patients who underwent RAPN and transfusion of blood products. Patient, tumor and operative variables were identified. From 2008 to 2021, 804 patients underwent RAPN, with 9 (1.1%) patients requiring a transfusion. Comparison of the transfused group with nontransfused patients yielded a significant difference in mean operative blood loss (527.8 ml vs 162.5 ml, p <0.0001), R.E.N.A.L. (for radius, exophytic/endophytic, nearness of tumor to collecting system, anterior/posterior, location relative to polar line) nephrometry score (7.1 vs 5.9, p <0.05), hemoglobin (11.3 gm/dl vs 13.9 gm/dl, p <0.05) and hematocrit (34.2% vs 41.4%, p <0.05). The variables associated with transfusion on univariate analysis were examined for predictive capacity using logistic regression. Operative blood loss (p <0.05), nephrometry score (p=0.05), hemoglobin (p <0.05) and hematocrit (p <0.05) remained associated with a transfusion. The hospital charge for blood typing and crossmatching was $1,320 USD per patient. With the maturity of RAPN techniques and outcomes, the extent of preoperative testing related to blood products should evolve to better reflect current procedural risks. Prioritizing testing resources for patients at increased complication risk can be based on predictive factors.

Abstract No. 54 Multi-institutional report of patient characteristics and oncologic outcomes following microwave ablation of biopsy-proven renal cell carcinoma

CT-guided thermal ablation is an option for treatment of small renal masses. The use of microwave ablation (MWA) for these tumors is increasing. We report patient characteristics and oncologic outcomes following microwave ablation of biopsy-proven RCC at 3 high-volume ablation centers.

Diagnosis and Treatment of Small Renal Masses: Where Do We Stand?

To present an overview of the current evidence-based studies covering diagnostic and management of SRM. Renal cell carcinoma (RCC) represents 3% of the cancers. Nowadays, partial nephrectomy (PN) represents gold standard treatment. New nephron-sparing approaches such as active surveillance and ablative therapies have been increasingly used as an alternative to surgical intervention. Due to novel comprehension of RCC and widespread use of imaging techniques, diagnosis at early stage in elderly patients has increased. Treatment decision-making should be based on patient and tumour characteristics. With expanding treatment options, the management of SRMs has become a debate and should be adjusted to patient and tumour characteristics. In a shared decision manner, both active surveillance with possible delayed intervention and focal therapy should be discussed with the patient as an alternative to partial nephrectomy.

PD33-09 MULTI-INSTITUTIONAL REPORT OF PATIENT CHARACTERISTICS AND ONCOLOGIC OUTCOMES FOLLOWING MICROWAVE ABLATION OF BIOPSY-PROVEN RENAL CELL CARCINOMA

You have accessJournal of UrologyCME1 May 2022PD33-09 MULTI-INSTITUTIONAL REPORT OF PATIENT CHARACTERISTICS AND ONCOLOGIC OUTCOMES FOLLOWING MICROWAVE ABLATION OF BIOPSY-PROVEN RENAL CELL CARCINOMA Leo Dreyfuss, Arighno Das, Kimberly Maciolek, Rand Wilcox Vanden Berg, Glenn Allen, Jonathan Fainberg, Tudor Borza, Shane Wells, Stephen Culp, E. Jason Abel, and Timothy McClure Leo DreyfussLeo Dreyfuss More articles by this author , Arighno DasArighno Das More articles by this author , Kimberly MaciolekKimberly Maciolek More articles by this author , Rand Wilcox Vanden BergRand Wilcox Vanden Berg More articles by this author , Glenn AllenGlenn Allen More articles by this author , Jonathan FainbergJonathan Fainberg More articles by this author , Tudor BorzaTudor Borza More articles by this author , Shane WellsShane Wells More articles by this author , Stephen CulpStephen Culp More articles by this author , E. Jason AbelE. Jason Abel More articles by this author , and Timothy McClureTimothy McClure More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002584.09AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: CT-guided thermal ablation is an option for the treatment of small renal masses. Patients with comorbidities may not tolerate extirpative surgery for localized renal cell carcinoma (RCC) and microwave ablation (MWA) may be considered. We report patient characteristics and outcomes following MWA of biopsy-proven RCC at three high-volume centers. METHODS: Consecutive patients with localized, non-metastatic, pathologically confirmed RCC treated with MWA at three centers were included. Images were reviewed by abdominal radiologists experienced with ablation. Contrast-enhanced CT was performed immediately following ablation to confirm technical success. Surveillance included abdominal cross-sectional imaging at 3-6 month intervals for 2 years and yearly thereafter. Local recurrence was defined radiographically as enhancing tumor within the ablation site following complete ablation. RESULTS: 541 ablations were performed in 492 patients. Patients with hereditary RCC syndromes (n=15), prior RCC (n=107), multifocal/bilateral tumors (n= 82), and benign/negative biopsy (n=27) were excluded. Final analysis included 370 patients (median age 68; 139 female) with sporadic, biopsy-proven RCC. 307 patients had cT1a tumors and 63 patients had cT1b or greater tumors. Compared with T1a tumors, patients with T1b tumors had higher body mass index, Charlson Comorbidity index, and ECOG performance status (p<0.05) but did not differ in gender or age. T1b tumors were more likely to be clear cell RCC (p=0.010) and high grade (0.028). 32 patients developed recurrences at a median time of 12 (IQR 6-26) months. Local recurrence free survival in the entire cohort was 88.7% at 36 months, 92.1% (95% CI 86.6-95.5) for T1a and 88.1% (95% CI 69.8-95.7) for T1b. Local recurrence free survival improved to 97.3% (95% CI 93.6-98.9) when repeat ablations were included in the analysis. Metastatic free survival was 98.2% at 36 months for all patients, 98.8% (95% CI 96.4-99.6) for T1a and 94.8% (95% CI 80.2-98.7) for T1b. RCC subtype and tumor grade were not associated with local recurrence in patients with T1a tumors. For T1b patients, high tumor grade was predictive of local recurrence (p=0.037). CONCLUSIONS: In this multi-institutional series of biopsy-proven RCC, metastatic spread was rare following MWA. Local control can be achieved for cT1a and cT1b tumors, though multiple ablation sessions may be necessary. Microwave ablation for cT1b masses may be a viable option for patients with medical comorbidities precluding surgical management. Source of Funding: None © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e556 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Leo Dreyfuss More articles by this author Arighno Das More articles by this author Kimberly Maciolek More articles by this author Rand Wilcox Vanden Berg More articles by this author Glenn Allen More articles by this author Jonathan Fainberg More articles by this author Tudor Borza More articles by this author Shane Wells More articles by this author Stephen Culp More articles by this author E. Jason Abel More articles by this author Timothy McClure More articles by this author Expand All Advertisement PDF DownloadLoading ...

A prospective randomized parallel-controlled pilot trial of stereotactic body radiation therapy versus radiofrequency ablation for the management of small renal masses.

363 Background: The potential of ablative technologies as an alternative to surgery for the treatment of small renal masses (SRMs) ≤4cm is unclear. Our objective was to evaluate the feasibility and toxicity of stereotactic body radiation therapy (SBRT) and radiofrequency ablation (RFA) for SRMs in a prospective randomized pilot trial. Methods: Patients scheduled for renal cell carcinoma (RCC) treatment at a single academic center were approached for the pilot trial, with the aim of recruiting 24 patients. Participants were assigned 1:1 to SBRT or RFA. Imaging (CT or MRI) using a renal tumor protocol is completed at 3, 6, 9, and 12 months post-procedure. Biopsies were completed prior to the procedure and at 12 months. Multiple clinical parameters were collected. Follow-up visits will occur at 6 month intervals following the trial up to 5 years. SBRT included an initial simulation session and a single image-guided treatment session with a prescribed dose of 25 Gy. RFA was conducted by either percutaneous or laparoscopic access with 2 cycles of 8 minutes duration each upon reaching target temperature. Results: Beginning in December 2019, 24 patients were recruited and randomized (SBRT = 11; RFA = 13). Eleven had SBRT, 8 RFA, 3 have not yet had treatment, and 2 became ineligible. Median age for all patients was 67 (53,85) and 17 were male. A total of 17 patients had clear cell RCC, 6 had papillary RCC (type 1), and 1 had chromophobe RCC. All patients had T1a disease. Mean procedure length (minutes) for SBRT and RFA was 15.5±7.4 and 10.5±3.9, respectively. Two patients (both SBRT) had a 12-month biopsy showing no evidence of recurrence or metastases, while two patients (1 RFA, 1 SBRT) had a 9-month CT showing no recurrence. Data are pending for the remaining patients. An early grade 2 flare-up occurred in one SBRT patient. Conclusions: Recruitment and randomization of patients with SRMs in a SBRT vs. RFA prospective trial is feasible on a timeline that allows for regular follow-up and imaging. To date, both treatment modalities have been shown to have excellent short-term safety profiles.

Disease Progression in Older Patients With Renal Tumor Assigned to an Active Surveillance Protocol.

Active surveillance (AS) is a validated option for the treatment of small renal masses (SMRs), especially in older patients. This study investigates the oncologic outcomes and competitive mortality of older patients prospectively assigned to AS. We conducted a monocentric study on patients ≥75 years treated between 2011 and 2016 for a SMR. Treatment modalities, biopsy data, survivals (overall, specific, cancer progression) and delayed interventions were analyzed. Overall, 106 patients (median age 80.5 years) were included, of which 41 were managed by AS during a follow-up of 3.4 years [0-7.1]. Seven patients (17%) had a primary biopsy with 3 confirmed renal cell carcinomas. Fourteen patients (34.1%) presented with progression (29.2% local; 4.9% metastatic), 8 (19.5%) requiring delayed interventions (75% ablative therapy and 25% radical nephrectomy). Overall survival (OS) was 68.3% and cancer specific survival was 95.1% during the study period. Competitive mortality was higher (84.6%) than cancer specific mortality (15.4%), P=.001. The growth rate of progression including 4.9% metastatic progression underlines the value of AS compared to simple watchful surveillance in the treatment of SMRs in older patients. Of note, the higher competitive mortality confirm that AS should be preferred to active intervention at the beginning of the management.

PD25-06 PERCUTANEOUS MICROWAVE ABLATION VS PARTIAL NEPHRECTOMY FOR SMALL RENAL MASSES: COST-EFFECTIVENESS ANALYSIS

You have accessJournal of UrologyHealth Services Research: Value of Care: Cost and Outcomes Measures II (PD25)1 Sep 2021PD25-06 PERCUTANEOUS MICROWAVE ABLATION VS PARTIAL NEPHRECTOMY FOR SMALL RENAL MASSES: COST-EFFECTIVENESS ANALYSIS Clinton Yeaman, Lauren O'Connor, Jennifer Lobo, Anthony DeNovio, Christopher Ballantyne, and Noah Schenkman Clinton YeamanClinton Yeaman More articles by this author , Lauren O'ConnorLauren O'Connor More articles by this author , Jennifer LoboJennifer Lobo More articles by this author , Anthony DeNovioAnthony DeNovio More articles by this author , Christopher BallantyneChristopher Ballantyne More articles by this author , and Noah SchenkmanNoah Schenkman More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002018.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: To perform a cost-effective analysis using a Markov model between percutaneous microwave ablation (MWA) and partial nephrectomy (PN) for treatment of small renal masses using both literature values and institutional outcome data. METHODS: We created a decision analytic Markov model depicting management of the small renal mass (percutaneous MWA vs robotic-assisted PN) incorporating costs, health utilities, and probabilities of complications and recurrence as model inputs from the literature. Iterations of the model were also cycled using our institutional outcome and financial data and various patient characteristics based on our IRB approved small renal mass database. Modeling was performed using Treeage (2020.2.1). A willingness to pay (WTP) threshold of $75,000 was used. RESULTS: Percutaneous MWA was the preferred treatment modality. MWA dominated RA-PN, meaning it resulted in more quality adjusted life years (QALYs) at a lower cost. Model inputs are shown in Table 1 and the model decision tree is shown in Figure 1. Cost-effectiveness analysis revealed an Incremental Cost Effectiveness Ratio (ICER) of -$6,847 per quality adjusted life-year (QALY). The model revealed a mean cost of MWA of $12,921 and 12.5 QALYs. Robotic-assisted PN had a mean cost of $21,477 and 11.2 QALYs. Sensitivity analysis was performed for all variables. Patient age of 39 years or younger resulted in RA-PN being favored over MWA. Both MWA and RA-PN are cost-effective approaches under this condition, but RA-PN is preferred at the WTP threshold. Relative preference of MWA was robust to sensitivity analysis of all other variables. Cost of PN and patient age had the most dramatic impact on ICER. It was more cost-effective if local recurrence was managed with MWA rather than partial or radical nephrectomy. CONCLUSIONS: Cost-effectiveness analysis demonstrates MWA is the preferred treatment of small renal masses when compared with RA-PN and accounting for complication and recurrence risk. Source of Funding: N/A © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e433-e434 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Clinton Yeaman More articles by this author Lauren O'Connor More articles by this author Jennifer Lobo More articles by this author Anthony DeNovio More articles by this author Christopher Ballantyne More articles by this author Noah Schenkman More articles by this author Expand All Advertisement Loading ...