Open and Robotic Uretero-enteric Stricture Repair: Early Outcomes and Complications.

Objective: To characterize our single institutional experience with robotic and open uretero-enteric stricture (UES) repair. Materials and Methods: We queried our ureteral reconstructive database for UES repair between 01/2017 and 10/2023. Patients with <3 months follow-up were excluded. Prior to surgery, patients underwent ureteral rest (4 weeks) with conversion to nephrostomy tube. Clinical characteristics, complications, reconstructive success (uretero-enteric patency), need for repeat intervention, and renal function were assessed in patients undergoing open and robotic UES reconstruction. Results: Of 50 patients undergoing UES repair during the study period, 45 were included for analysis due to complete follow-up (34 [76%] robotic and 11 [24%] open repair). UES repair was performed in 50 renal units a median of 13 months (interquartile range 7-30) from index surgery, and most often involved the left renal unit (34/50; 68%). Compared with robotic, open cases were significantly more likely to have undergone open cystectomy (100% vs 68%, p = 0.04), have longer strictures (median 4 vs 1 cm, p < 0.001), require tissue substitution (27% vs 3%, p = 0.04), and have lengthier postoperative hospitalization (5 vs 2 days, p < 0.001). There was no significant difference in total operative time (410 vs 322 minutes) or 30d major complications (18% vs 21%). At a follow-up of 13 months, per patient reconstructive success was 100% (11/11) for open and 97% (33/34) for robotic, respectively. Conclusion: In select patients with short UES unlikely to require advanced reconstructive techniques, a robotic-assisted approach can be considered. Careful patient selection is associated with limited morbidity and high reconstructive success.

End-Stage Kidney Disease After Partial and Radical Nephrectomy Among Patients with Severe Chronic Kidney Disease.

PURPOSE: AUA guidelines prioritize nephron sparing in patients with preexisting chronic kidney disease (CKD). However, few studies analyze long-term renal function in patients with preoperative severe CKD who undergo extirpative renal surgery. Herein, we compare the hazard of progression to end-stage kidney disease (ESKD) following partial nephrectomy (PN) and radical nephrectomy (RN) among patients with preoperative severe CKD. MATERIALS AND METHODS: Patients with stage 4 CKD who underwent PN or RN from 1970 to 2018 were identified. A multivariable Fine-Gray subdistribution hazard model was employed to assess associations with progression to ESKD accounting for the competing risk of death. RESULTS: A total of 186 patients with stage 4 CKD underwent PN (n = 71; 38%) or RN (n = 115; 62%) for renal neoplasms with median follow-up of 6.9 years (interquartile range 3.8-14.1). On multivariable analyses adjusting for competing risk of death, the subdistribution hazard ratio (SHR) for older age at surgery (SHR for 5-year increase 0.81; 95% CI 0.73-0.91; P < .001) and higher preoperative estimated glomerular filtration rate (SHR for 5-unit increase 0.63; 95% CI 0.47-0.84; P = .002) was associated with lower hazard of progression to ESKD. There was no significant difference in hazard of ESKD between PN and RN (SHR 0.82; 95% CI 0.50-1.33; P = .4). CONCLUSIONS: Among patients with preoperative severe CKD, higher preoperative estimated glomerular filtration rate was associated with lower hazard of progression to ESKD after extirpative surgery for renal neoplasms. We did not observe a significant difference in overall hazard for developing ESKD between PN and RN.

Incidence and predictors of ipsilateral local recurrence following partial nephrectomy.

PURPOSE: Ipsilateral local recurrence (LR) after partial nephrectomy (PN) for renal cell carcinoma (RCC) may result from a metachronous tumor or PN bed recurrence. To date, literature has predominantly reported ipsilateral LRs collectively, although the pathophysiology and prognostic implications of these event may be distinct. We sought to assess variables associated with LR and evaluated associations of LR with metastasis and death from RCC. MATERIALS AND METHODS: We identified adults undergoing PN for unilateral, sporadic, localized RCC from 2000 to 2019 using a prospectively maintained, single institution registry. LR was defined as new, enhancing tumor within/near the PN bed on MRI/CT. Cox proportional hazards models were used to create a preoperative risk score for LR and to examine the association of LR with metastasis and CSS following PN among patients with clear cell RCC. RESULTS: In a cohort of 2,164 PNs, 106 true LRs were identified, for a 10-year incidence of 6.2%. A preoperative risk score for LR based on age, symptoms, solitary kidney, complex tumor necessitating open partial nephrectomy, and cT stage was created (c-index = 0.73). Postoperatively, positive margins, pT stage, and clear cell subtype were associated with LR. Notably, 21% (23/106) of patients with LR presented with synchronous metastases. Following LR, 5-year metastasis-free and cancer-specific survival were 64% and 71%, respectively. LR remained associated with metastasis (HR 6.25; P < 0.001) and death from RCC (HR 1.93; P = 0.03) on multivariable analysis. CONCLUSIONS: We developed a preoperative risk score to identify patients at risk for LR following PN. LR was an independent risk factor for metastasis and death from RCC. Further study is warranted to determine whether treatment of LR improves oncologic outcomes.

Mayo Clinic Validation of the AUA Risk Groups for Localized Renal Cell Carcinoma.

PURPOSE: The AUA guidelines introduced a new risk group stratification system based primarily on tumor stage and grade to guide surveillance for patients treated surgically for localized renal cell carcinoma (RCC). We sought to evaluate the predictive ability of these risk groups using progression-free survival (PFS) and cancer-specific survival (CSS), and to compare their performance to that of our published institutional risk models. MATERIALS AND METHODS: We queried our Nephrectomy Registry to identify adults treated with radical or partial nephrectomy for unilateral, M0, clear cell RCC, or papillary RCC from 1980 to 2012. The AUA stratification does not apply to other RCC subtypes as tumor grading for other RCC, such as chromophobe, is not routinely performed. PFS and CSS were estimated using the Kaplan-Meier method. Predictive abilities were evaluated using C indexes from Cox proportional hazards regression models. RESULTS: A total of 3191 patients with clear cell RCC and 633 patients with papillary RCC were included. For patients with clear cell RCC, C indexes for the AUA risk groups and our model were 0.780 and 0.815, respectively (P < .001) for PFS, and 0.811 and 0.857, respectively (P < .001), for CSS. For patients with papillary RCC, C indexes for the AUA risk groups and our model were 0.775 and 0.751, respectively (P = .002) for PFS, and 0.830 and 0.803, respectively (P = .2) for CSS. CONCLUSIONS: The AUA stratification is a parsimonious system for categorizing RCC that provides C indexes of about 0.80 for PFS and CSS following surgery for localized clear cell and papillary RCC.

Initial Experience and Clinical Assessment of the Karl Storz FLEX-XC1 Single-Use Flexible Ureteroscope.

INTRODUCTION: The Karl Storz FLEX-XC1 is a novel single-use flexible ureteroscope that uses the same videographics platform as its reusable digital counterpart. We evaluated the technical performance of the FLEX-XC1 in its initial clinical use. METHODS: We reviewed a series of consecutive ureteroscopy procedures performed by 2 endourologists using the FLEX-XC1 for indications for which we typically use a single-use device: total stone burden > 15 mm or > 10 mm in the lower pole, anticipated case duration > 60 minutes, bilateral procedure, or upper tract urothelial cancer procedures. We assessed device tip deflection, intraoperative mechanical failure, and clinical outcomes for each case. Surgeons rated visual clarity, image quality, and maneuverability on a 1 to 5 Likert scale. RESULTS: Of 29 procedures using FLEX-XC1, 27 (93%) were successfully completed. Preoperative upward deflection was < 270° in 6 (21%) cases, and downward deflection was < 270° in 9 (31%) cases. Three types of intraoperative malfunctions occurred: rotational twisting of deflectable tip (4 cases, 13%), device not advancing through distal ureter (1 case, 3%), and working channel not accommodating a 365-µm laser (1 case, 3%). Visual clarity, image quality, and maneuverability were rated as 5 "very good" or 4 "good" in 100%, 100%, and 97% of cases, respectively. No device-specific or general 30-day complications were observed. CONCLUSIONS: The FLEX-XC1 showed comparable image quality and maneuverability to reusable digital devices. We observed incomplete deflection in up to 31% of cases and mechanical failure in 2 cases. The FLEX-XC1 may be advantageous in prolonged cases where maintaining visual clarity is paramount.

Development and Validation of a Multivariable Nomogram Predictive of Post-Nephroureterectomy Renal Function.

BACKGROUND AND OBJECTIVE: The timing of perioperative nephrotoxic chemotherapy for upper tract urothelial carcinoma (UTUC) remains controversial and strongly depends on predicted platinum eligibility after radical nephroureterectomy (RNU). The study objective was to develop and validate a multivariable nomogram to predict estimated glomerular filtration rate (eGFR) following RNU. METHODS: This was a multi-institutional retrospective study of patients with UTUC treated with RNU from 2000 to 2020 at seven high-volume referral centers. Use of adjuvant chemotherapy was risk-stratified. Patients were retrospectively randomly allocated 2:1 to discovery and validation cohorts. Discovery data were used to identify independent factors associated with GFR at 1-3 mo after RNU on linear regression, and backward selection was applied for model construction. Accuracy was defined as the percentage of predicted eGFR results within 30% of the corresponding observed eGFR. KEY FINDINGS AND LIMITATIONS: We included 1100 patients, of whom 733 were in the discovery and 367 were in the validation cohort. Multivariable predictors of postoperative eGFR decline included advanced age (odds ratio [OR] -0.18, 95% confidence interval [CI] -0.28 to -0.08), diabetes (OR -2.38, 95% CI -4.64 to -0.11), and hypertension (OR -2.24, 95% CI -4.16 to -0.32). Factors associated with favorable postoperative eGFR included larger tumor size (OR 10.57, 95% CI 7.4-13.74 for tumors >5 cm vs ≤2 cm) and preoperative eGFR (OR 0.44, 95% CI 0.39-0.49). A composite nomogram predicted postoperative eGFR with good accuracy in both the discovery (80.5%) and validation (78.6%) cohorts. Limitations include exclusion of patients who received neoadjuvant chemotherapy. CONCLUSIONS: A nomogram that incorporates ubiquitous preoperative clinical variables can predict post-RNU eGFR and was validated with an independent cohort. PATIENT SUMMARY: We developed a tool that uses patient data to predict eligibility for chemotherapy after surgery to remove the kidney and ureter in patients with cancer in the upper urinary tract.

Oncologic Outcomes in Patients with Residual Upper Tract Urothelial Carcinoma Following Neoadjuvant Chemotherapy.

BACKGROUND AND OBJECTIVE: Growing evidence supports the use of neoadjuvant chemotherapy (NAC) for upper tract urothelial carcinoma (UTUC). However, the implications of residual UTUC at radical nephroureterectomy (RNU) after NAC are not well characterized. Our objective was to compare oncologic outcomes for pathologic risk-matched patients who underwent RNU for UTUC who either received NAC or were chemotherapy-naïve. METHODS: We retrospectively identified 1993 patients (including 112 NAC recipients) who underwent RNU for nonmetastatic, high-grade UTUC between 1985 and 2022 in a large, international, multicenter cohort. We divided the cohort into low-risk and high-risk groups defined according to pathologic findings of muscle invasion and lymph node involvement at RNU. Recurrence-free survival (RFS), overall survival (OS), and cancer-specific survival (CSS) estimates were calculated using the Kaplan-Meier method. Multivariable analyses were performed to determine clinical and demographic factors associated with these outcomes. KEY FINDINGS AND LIMITATIONS: Among patients with low-risk pathology at RNU, RFS, OS, and CSS were similar between the NAC and chemotherapy-naïve groups. Among patients with high-risk pathology at RNU, the NAC group had poorer RFS (hazard ratio [HR] 3.07, 95% confidence interval [CI] 2.10-4.48), OS (HR 2.06, 95% CI 1.33-3.20), and CSS (subdistribution HR 2.54, 95% CI 1.37-4.69) in comparison to the pathologic risk-matched, chemotherapy-naïve group. Limitations include the lack of centralized pathologic review. CONCLUSIONS AND CLINICAL IMPLICATIONS: Patients with residual invasive disease at RNU after NAC represent a uniquely high-risk population with respect to oncologic outcomes. There is a critical need to determine an optimal adjuvant approach for these patients. PATIENT SUMMARY: We studied a large, international group of patients with cancer of the upper urinary tract who underwent surgery either with or without receiving chemotherapy beforehand. We identified a high-risk subgroup of patients with residual aggressive cancer after chemotherapy and surgery who should be prioritized for clinical trials and drug development.

Percutaneous Image Guided Cryoablation of Adrenal Metastases From Renal Cell Carcinoma: A Single Institution Review.

OBJECTIVES: To assess the safety, technical success, disease progression, and survival associated with percutaneous image-guided cryoablation of renal cell carcinoma metastasis (mRCC) in the adrenal gland. METHODS: Retrospective, single-institution review of adult patients undergoing percutaneous cryoablation for adrenal mRCC between the years of 2007-2021. Technical parameters, technical success, safety, and survival were analyzed according to standard criteria. RESULTS: Forty-six patients (39 male; mean age 66 ± 8.8 years) with 57 tumors ablated over 51 sessions with a median hospital length of stay of 1 day (range 0-3 days). Forty-four (96%) had primary of clear cell histology. Aim of ablation was curative intent in 39 of 57 tumors (72%) with local tumor control in the remainder. There were 2 (4%) technical failures and technique efficacy was achieved in 52 out of the remaining 55 (95%). There were no Common Terminology Criteria for Adverse Events' immediate complications and 4 of 51 (8%) delayed complications. Twenty-five of 57 (44%) had disease progression anywhere, away from ablation site. One-, 3-, and 5-year recurrence free survival rates were 100%, 89%, and 89% and overall survival was 98%, 85%, and 71%. Fifty-one of 57 (89%) underwent preprocedural alpha blockade with hypertensive crisis in 27 of 56 (54%) available records, of which there were no adverse outcomes. CONCLUSION: Percutaneous cryoablation of mRCC to the adrenal glands is safe with robust local control, leading to advocacy for its ongoing use in this patient population. Multi-disciplinary management is recommended for successful treatment.

Diagnosis and Management of Non-Metastatic Upper Tract Urothelial Carcinoma: AUA/SUO Guideline.

PURPOSE: The purpose of this guideline is to provide a useful reference on the effective evidence-based diagnoses and management of non-metastatic upper tract urothelial carcinoma (UTUC). MATERIALS/METHODS: The Pacific Northwest Evidence-based Practice Center of Oregon Health & Science University (OHSU) team conducted searches in Ovid MEDLINE (1946 to March 3rd, 2022), Cochrane Central Register of Controlled Trials (through January 2022), and Cochrane Database of Systematic Reviews (through January 2022). The searches were updated August 2022. When sufficient evidence existed, the body of evidence was assigned a strength rating of A (high), B (moderate), or C (low) for support of Strong, Moderate, or Conditional Recommendations. In the absence of sufficient evidence, additional information is provided as Clinical Principles and Expert Opinions (Table 1).[Table: see text]Results:This Guideline provides updated, evidence-based recommendations regarding diagnosis and management of non-metastatic UTUC including risk stratification, surveillance and survivorship. Treatments discussed include kidney sparing management, surgical management, lymph node dissection (LND), neoadjuvant/adjuvant chemotherapy and immunotherapy. CONCLUSION: This standardized guideline seeks to improve clinicians' ability to evaluate and treat patients with UTUC based on available evidence. Future studies will be essential to further support these statements for improving patient care. Updates will occur as the knowledge regarding disease biology, clinical behavior and new therapeutic options develop.

Healthcare system contact following ureteroscopy: does discharge instruction readability matter?

INTRODUCTION: We aimed to assess the impact of discharge instruction (DCI) readability on 30-day postoperative contact with the healthcare system. MATERIALS AND METHODS: Utilizing a multidisciplinary team, DCI were modified for patients undergoing cystoscopy, retrograde pyelogram, ureteroscopy, laser lithotripsy, and stent placement (CRULLS) from a 13th grade to a 7th grade reading level. We retrospectively reviewed 100 patients including 50 consecutive patients with original DCI (oDCI) and 50 consecutive patients with improved readability DCI (irDCI). Clinical and demographic data collected including healthcare system contact (communications [phone or electronic message], emergency department [ED], and unplanned clinic visits) within 30 days of surgery. Uni/multivariate logistic regression analyses used to identify factors, including DCI-type, associated with increased healthcare system contact. Findings reported as odds ratios with 95% confidence intervals and p values (< 0.05 significant). RESULTS: There were 105 contacts to the healthcare system within 30 days of surgery: 78 communications, 14 ED visits and 13 clinic visits. There were no significant differences between cohorts in the proportion of patients with communications (p = 0.16), ED visits (p =1.0) or clinic visits (p = 0.37). On multivariable analysis, older age and psychiatric diagnosis were associated with significantly increased odds of overall healthcare contact (p = 0.03 and p = 0.04) and communications (p = 0.02 and p = 0.03). Prior psychiatric diagnosis was also associated with significantly increased odds of unplanned clinic visits (p = 0.003). Overall, irDCI were not significantly associated with the endpoints of interest. CONCLUSIONS: Increasing age and prior psychiatric diagnosis, but not irDCI, were significantly associated with an increased rate of healthcare system contact following CRULLS.

Effect of Dataset Size and Medical Image Modality on Convolutional Neural Network Model Performance for Automated Segmentation: A CT and MR Renal Tumor Imaging Study.

The aim of this study is to investigate the use of an exponential-plateau model to determine the required training dataset size that yields the maximum medical image segmentation performance. CT and MR images of patients with renal tumors acquired between 1997 and 2017 were retrospectively collected from our nephrectomy registry. Modality-based datasets of 50, 100, 150, 200, 250, and 300 images were assembled to train models with an 80-20 training-validation split evaluated against 50 randomly held out test set images. A third experiment using the KiTS21 dataset was also used to explore the effects of different model architectures. Exponential-plateau models were used to establish the relationship of dataset size to model generalizability performance. For segmenting non-neoplastic kidney regions on CT and MR imaging, our model yielded test Dice score plateaus of [Formula: see text] and [Formula: see text] with the number of training-validation images needed to reach the plateaus of 54 and 122, respectively. For segmenting CT and MR tumor regions, we modeled a test Dice score plateau of [Formula: see text] and [Formula: see text], with 125 and 389 training-validation images needed to reach the plateaus. For the KiTS21 dataset, the best Dice score plateaus for nn-UNet 2D and 3D architectures were [Formula: see text] and [Formula: see text] with number to reach performance plateau of 177 and 440. Our research validates that differing imaging modalities, target structures, and model architectures all affect the amount of training images required to reach a performance plateau. The modeling approach we developed will help future researchers determine for their experiments when additional training-validation images will likely not further improve model performance.

Comparing Oncological and Perioperative Outcomes of Open versus Laparoscopic versus Robotic Radical Nephroureterectomy for the Treatment of Upper Tract Urothelial Carcinoma: A Multicenter, Multinational, Propensity Score-Matched Analysis.

OBJECTIVES: To identify correlates of survival and perioperative outcomes of upper tract urothelial carcinoma (UTUC) patients undergoing open (ORNU), laparoscopic (LRNU), and robotic (RRNU) radical nephroureterectomy (RNU). METHODS: We conducted a retrospective, multicenter study that included non-metastatic UTUC patients who underwent RNU between 1990-2020. Multiple imputation by chained equations was used to impute missing data. Patients were divided into three groups based on their surgical treatment and were adjusted by 1:1:1 propensity score matching (PSM). Survival outcomes per group were estimated for recurrence-free survival (RFS), bladder recurrence-free survival (BRFS), cancer-specific survival (CSS), and overall survival (OS). Perioperative outcomes: Intraoperative blood loss, hospital length of stay (LOS), and overall (OPC) and major postoperative complications (MPCs; defined as Clavien-Dindo > 3) were assessed between groups. RESULTS: Of the 2434 patients included, 756 remained after PSM with 252 in each group. The three groups had similar baseline clinicopathological characteristics. The median follow-up was 32 months. Kaplan-Meier and log-rank tests demonstrated similar RFS, CSS, and OS between groups. BRFS was found to be superior with ORNU. Using multivariable regression analyses, LRNU and RRNU were independently associated with worse BRFS (HR 1.66, 95% CI 1.22-2.28, p = 0.001 and HR 1.73, 95%CI 1.22-2.47, p = 0.002, respectively). LRNU and RRNU were associated with a significantly shorter LOS (beta -1.1, 95% CI -2.2-0.02, p = 0.047 and beta -6.1, 95% CI -7.2-5.0, p < 0.001, respectively) and fewer MPCs (OR 0.5, 95% CI 0.31-0.79, p = 0.003 and OR 0.27, 95% CI 0.16-0.46, p < 0.001, respectively). CONCLUSIONS: In this large international cohort, we demonstrated similar RFS, CSS, and OS among ORNU, LRNU, and RRNU. However, LRNU and RRNU were associated with significantly worse BRFS, but a shorter LOS and fewer MPCs.

Biological and prognostic implications of biopsy upgrading for high-grade upper tract urothelial carcinoma at nephroureterectomy.

OBJECTIVES: Technical limitations of ureteroscopic (URS) biopsy has been considered responsible for substantial upgrading rate in upper tract urothelial carcinoma (UTUC). However, the impact of tumor specific factors for upgrading remain uninvestigated. METHODS: Patients who underwent URS biopsy were included between 2005 and 2020 at 13 institutions. We assessed the prognostic impact of upgrading (low-grade on URS biopsy) versus same grade (high-grade on URS biopsy) for high-grade UTUC tumors on radical nephroureterectomy (RNU) specimens. RESULTS: This study included 371 patients, of whom 112 (30%) and 259 (70%) were biopsy-based low- and high-grade tumors, respectively. Median follow-up was 27.3 months. Patients with high-grade biopsy were more likely to harbor unfavorable pathologic features, such as lymphovascular invasion (p < 0.001) and positive lymph nodes (LNs; p < 0.001). On multivariable analyses adjusting for the established risk factors, high-grade biopsy was significantly associated with worse overall (hazard ratio [HR] 1.74; 95% confidence interval [CI], 1.10-2.75; p = 0.018), cancer-specific (HR 1.94; 95% CI, 1.07-3.52; p = 0.03), and recurrence-free survival (HR 1.80; 95% CI, 1.13-2.87; p = 0.013). In subgroup analyses of patients with pT2-T4 and/or positive LN, its significant association retained. Furthermore, high-grade biopsy in clinically non-muscle invasive disease significantly predicted upstaging to final pathologically advanced disease (≥pT2) compared to low-grade biopsy. CONCLUSIONS: High tumor grade on URS biopsy is associated with features of biologically and clinically aggressive UTUC tumors. URS low-grade UTUC that becomes upgraded to high-grade might carry a better prognosis than high-grade UTUC on URS. Tumor specific factors are likely to be responsible for upgrading to high-grade on RNU.

Environmental impact of single-use and reusable flexible cystoscopes.

OBJECTIVES: To compare the carbon footprint and environmental impact of single-use and reusable flexible cystoscopes. MATERIALS AND METHODS: We analysed the expected clinical lifecycle of single-use (Ambu aScope™ 4 Cysto) and reusable (Olympus CYF-V2) flexible cystoscopes, from manufacture to disposal. Performance data on cumulative procedures between repairs and before decommissioning were derived from a high-volume multispecialty practice. We estimated carbon expenditures per-case using published data on endoscope manufacturing, energy consumption during transportation and reprocessing, and solid waste disposal. RESULTS: A fleet of 16 reusable cystoscopes in service for up to 135 months averaged 207 cases between repairs and 3920 cases per lifecycle. Based on a manufacturing carbon footprint of 11.49 kg CO2 /kg device for reusable flexible endoscopes and 8.54 kg CO2 /kg device for single-use endoscopes, the per-case manufacturing cost was 1.37 kg CO2 for single-use devices and 0.0017 kg CO2 for reusable devices. The solid mass of single-use and reusable devices was 0.16 and 0.57 kg, respectively. For reusable devices, the energy consumption of reusable device reprocessing using an automated endoscope reprocessor was 0.20 kg CO2 , and per-case costs of device repackaging and repair were 0.005 and 0.02 kg CO2 , respectively. The total estimated per-case carbon footprint of single-use and reusable devices was 2.40 and 0.53 kg CO2 , respectively, favouring reusable devices. CONCLUSION: In this lifecycle analysis, the environmental impact of reusable flexible cystoscopes is markedly less than single-use cystoscopes. The primary contributor to the per-case carbon cost of reusable devices is energy consumption of reprocessing.

Perioperative and Oncologic Outcomes Associated with Simultaneous Radical Cystectomy and Nephroureterectomy.

OBJECTIVE: To compare the perioperative and oncologic outcomes associated with RCNU to a matched cohort undergoing RC alone. Simultaneous radical cystectomy and nephroureterectomy (RCNU) for synchronous upper tract and bladder urothelial carcinoma is an uncommon procedure. Sparse literature exists comparing outcomes in patients treated with radical cystectomy (RC) alone versus RCNU. METHODS: Adults treated with RCNU for urothelial carcinoma of the bladder (UCB) and upper tract urothelial carcinoma (UTUC) between 1980 and 2020 were identified. Patients were matched 2:1 to patients undergoing RC alone for UCB based on age (+/- 5 years), gender, BMI (+/- 5), Charlson Comorbidity Index, pathologic staging (stage ≤pT2 vs >pT2), and receipt of neoadjuvant chemotherapy. Outcomes included overall survival (OS), recurrence free survival (RFS), cancer specific survival (CSS), 30-day complications, length of stay (LOS), operative time, and estimated blood loss (EBL). RESULTS: A total of 39 patients undergoing RCNU were identified and matched to 74 patients undergoing RC. There were no significant differences in LOS, EBL, or 30-day complication rates. Operative time was significantly longer in the RC cohort. OS (HR 0.58, CI 0.35-0.97, P = .036) was significantly better for patients undergoing RC alone, while no significant difference was noted in RFS (HR 0.65, 0.34-1.24) and CSS (HR 0.58, CI 0.31-1.08, P = .08). CONCLUSIONS: Patients undergoing RCNU had significantly lower OS compared to a matched group of patients undergoing RC alone. Perioperative outcomes between the groups did not differ significantly. This data can inform patient counseling for treatment of this rare disease state.

Diagnostic Accuracy of Clinical Lymph Node Staging for Upper Tract Urothelial Cancer Patients: A Multicenter, Retrospective, Observational Study.

PURPOSE: Treatment options for the management of upper tract urothelial cancer are based on accurate staging. However, the performance of conventional cross-sectional imaging for clinical lymph node staging (N-staging) remains poorly investigated. This study aims to evaluate the diagnostic accuracy of conventional cross-sectional imaging for upper tract urothelial cancer N-staging. MATERIALS AND METHODS: This study was a multicenter, retrospective, observational study. We included 865 nonmetastatic (M0) upper tract urothelial cancer patients treated with curative intended surgery and lymph node dissection who had been staged with conventional cross-sectional imaging before surgery. We compared clinical (c) and pathological (p) N-staging results to evaluate the concordance of node-positive (N+) and node-negative (N0) disease and calculate cN-staging's diagnostic accuracy. RESULTS: Conventional cross-sectional imaging categorized 750 patients cN0 and 115 cN+. Lymph node dissection categorized 641 patients pN0 and 224 pN+. The cN-stage was pathologically downstaged in 6.8% of patients, upstaged in 19%, and found concordant in 74%. The sensitivity and specificity of cN-staging were 25% (95% CI 20; 31) and 91% (95% CI 88; 93). Positive and negative likelihood ratios were 2.7 (95% CI 2.0; 3.8) and 0.83 (95% CI 0.76; 0.89). The area under the receiver operating characteristics curve (0.58, 95% CI 0.55; 0.61) revealed low diagnostic accuracy. CONCLUSIONS: Conventional cross-sectional imaging had low sensitivity in detecting upper tract urothelial cancer pN+ disease. However, cN+ increased the likelihood of pN+ by almost threefold. Thus, conventional cross-sectional imaging is a rule-in but not a rule-out test. Lymph node dissection should remain the standard during extirpative upper tract urothelial cancer surgery to obtain accurate N-staging. cN+ could be a strong argument for early systemic treatment.

In Vivo Prediction of Kidney Stone Fragility Using Radiomics-Based Regression Models.

Introduction: The surgical technique for urinary stone removal is partly influenced by its fragility, as prognosticated by the clinician. This feasibility study aims to develop a linear regression model from CT-based radiomic markers to predict kidney stone comminution time in vivo with two ultrasonic lithotrites. Materials and Methods: Patients identified by urologists at our institution as eligible candidates for percutaneous nephrolithotomy were prospectively enrolled. The active engagement time of the lithotrite in breaking the stone during surgery denoted the comminution time of each stone. The comminution rate was computed as the stone volume disintegrated per minute. Stones were grouped into three fragility classes (fragile, moderate, hard), based on inverse of the comminution rates with respect to the mean. Multivariable linear regression models were trained with radiomic features extracted from clinical CT images to predict comminution times in vivo. The model with the least root mean squared error (RMSE) on comminution times and the fewest misclassification of fragility was finally selected. Results: Twenty-eight patients with 31 stones in total were included in this study. Stones in the cohort averaged 1557 (±2472) mm3 in volume and 5.3 (±7.4) minutes in comminution time. Ten stones had nonmoderate fragility. Linear regression of stone volume alone predicted comminution time with an RMSE of 6.8 minutes and missed all 10 stones with nonmoderate fragility. A fragility model that included stone volume, internal morphology, shape-based radiomics, and device type improved RMSE to below 3.3 minutes and correctly classified 20/21 moderate and 6/10 nonmoderate stones. Conclusions: CT metrics-based fragility models may provide information to surgeons regarding kidney stone fragility and facilitate the selection of stone removal procedures.

Progression of Chronic Kidney Disease Following Radical and Partial Nephrectomy.

OBJECTIVE: To compare renal functional outcomes, as determined by percent decline in estimated glomerular filtration rate (eGFR) and CKD stage progression following radical (RN) and partial nephrectomy (PN) stratified by preoperative CKD stage. MATERIALS AND METHODS: We retrospectively evaluated adults treated with RN or PN between 1980 and 2018 for unilateral, sporadic, solid renal masses. Multivariable linear models for percent change in eGFR (n = 3046) and competing-risk Cox proportional hazards models for increase in CKD staging (n = 5805) were used to determine if there was a significant interaction between type of surgery (RN vs PN) and preoperative CKD stage. RESULTS: Percent change in eGFR at 1 year was significantly worse for RN (n = 1724; 57%) compared with PN (n = 1322; 43%) for all preoperative CKD stages. RN (n = 3227; 56%) was more likely to result in CKD stage progression compared with PN (n = 2578; 44%) for preoperative CKD stages I-IIIb (P <.001) but not for CKD stage IV (P = .8). CONCLUSION: RN was more likely to result in decline in eGFR and CKD stage progression compared to PN for patients with preoperative CKD stage IIIb or less. Additionally, RN was associated with a significantly greater decline in eGFR at 1 year relative to PN in the CKD stage IV subset. Our data support performing PN for renal preservation when feasible.

Renin Production by Juxtaglomerular Cell Tumors and Clear Cell Renal Cell Carcinoma and the Role of Angiotensin Signaling Inhibitors.

OBJECTIVE: To profile juxtaglomerular cell tumors (JXG) and histologic mimics by analyzing renin expression; to identify non-JXG renin-producing tumors in The Cancer Genome Atlas (TCGA) data sets; and to define the prevalence of hypertension (HTN) and patient outcomes with angiotensin signaling inhibitor (ASI) use in tumors of interest. PATIENTS AND METHODS: Thirteen JXGs and 10 glomus tumors (GTs), a histologic mimic, were evaluated for clinicopathologic features; TCGA data were analyzed to identify non-JXG renin-overexpressing tumors. An institutional registry was queried to determine the incidence of HTN, the use of ASIs in hypertensive patients, and the impact of ASIs on outcomes including progression-free survival (PFS) in a tumor type with high renin expression (clear cell renal cell carcinoma [CC-RCC] diagnosed between January 1, 2005, and December 31, 2012). RESULTS: We found an association between renin production and HTN in JXG compared with GT. Analysis of TCGA data found that a subset of CC-RCCs overexpress renin relative to 29 other tumor types. Furthermore, analysis of our institutional registry revealed a high prevalence (64%) of HTN among 1203 patients treated with radical or partial nephrectomy for nonmetastatic CC-RCC. On multivariable Cox regression, patients with HTN treated with ASIs (34%) had improved PFS (hazard ratio, 0.76; 95% CI, 0.57 to 1.00; P=.05) compared with patients with HTN not treated with ASIs (30%). CONCLUSION: The identification of renin expression in a subset of CC-RCC may provide a biologic rationale for the high prevalence of HTN and improved PFS with ASI use in hypertensive patients with nonmetastatic CC-RCC.