Preoperative three-dimensional modelling and virtual reality planning aids nephron sparing surgery in a child with bilateral Wilms tumour.

Bilateral Wilms tumour (BWT) is a surgically challenging condition. Virtual reality (VR) reconstruction aids surgeons to foresee the anatomy ahead of Nephron Sparing Surgery (NSS). Three-dimensional (3D) visualisation improves the anatomical orientation of surgeons performing NSS. We herewith report a case of BWT where VR planning and 3D printing were used to aid NSS. Conventional imaging is often found to be inadequate while assessing the tumour-organ-vascular anatomy. Advances like VR and 3D printing help surgeons plan better for complex surgeries like bilateral NSS. Next-generation extended reality tools will likely aid robotic-assisted precision NSS and improve patient outcomes.

[Oncological results of repeat partial nephrectomy in patients with recurrence after nephron-sparing procedures].

AIM: To carried out a comparative analysis of the risk of complications and oncological results of repeat partial nephrectomy and radical nephrectomy in patients with local recurrence after previous organ-sparing procedures. MATERIALS AND METHODS: Retrospective and prospective data of 64 patients with local recurrence of kidney cancer after nephron-sparing procedures. who underwent surgical treatment in the department of oncourology of the National Medical Research Center of Oncology named after N.N. Blokhin in the period from 2000 to 2022. A total of 37 (57.8%) patients of the main group underwent repeat partial nephrectomy, while in 27 (42.2%) patients in the control group a radical nephrectomy was done. Median follow-up was 35 (3-131; Q1-Q3: 13-57) months. Both groups were comparable in terms of demographic and clinical characteristics (p>0.05). The median time to detect relapse after previous partial nephrectomy was 24 (2-172) months. RESULTS: Complications were noted in 8 (21.6%) patients after repeat partial nephrectomy, compared to 29.6% in the control group (n=8) (p=0.563). A comparative analysis revealed a significant advantage in overall survival in patients of the main group (p=0.042). There were no significant differences between groups in cancer-specific and disease-free survival (p=0.369 and p=0.537, respectively). CONCLUSION: Repeat partial nephrectomy for local recurrence of kidney cancer leads to an increase in overall survival compared to radical nephrectomy, in the absence of significant differences in cancer-specific and relapse-free survival.

Robotic transperitoneal versus retroperitoneal approach for anterior renal mass nephron-sparing surgery.

Robotic nephron-sparing surgery is traditionally performed via a transperitoneal (TP) approach. However, the retroperitoneal (RP) approach has gained popularity, particularly for posterolateral renal masses. The RP approach is associated with shorter operative time, less blood loss, and shorter length of stay, while preserving oncologic outcomes in selected masses. Here, we aim to assess the feasibility of the RP approach in excising anterior renal masses. Patients ≥ 18 years of age who underwent robotic nephron-sparing surgery for anterior renal masses were retrospectively identified (2008-2022). Baseline demographics, tumor characteristics, and perioperative data were collected and characterized based on TP vs RP approaches. Wilcoxon rank sum test and Pearson's Chi-squared test were used to compare continuous and categorical variables, respectively. Two hundred and sixteen patients were included-178 (82.4%) underwent TP approach and 38 (17.6%) underwent RP approach. Baseline demographics, preoperative tumor size, and renal nephrometry scores were similar. The RP approach was associated with shorter operative (150 vs 203 min, p < 0.001) and warm ischemia time (12 vs 21 min, p < 0.001), and less blood loss (20 vs 100 cc, p = 0.002) (Table 1). The RP approach was associated with shorter length of stay (1 vs 2 days, p < 0.001) and less total complications (5.3% vs 19.1%, p = 0.038). Major complication (Clavien-Dindo Grade > 3) rates were similar. There was no difference in positive surgical margin rates or pathologic characteristics. Robotic RP approach for nephron-sparing surgery is feasible for eligible anterior tumors and is associated with favorable perioperative outcomes with preserved negative surgical margin rates. Table 1 Patient baseline demographics Overall Transperitoneal Retroperitoneal p value Median/N IQR/% Median/N IQR/% Median/N IQR/% N 216 178 82.4% 38 17.6% Age (years) 60.5 (52.1-67.7) 60.4 (52.8-67.7) 61.6 (49.1-69.2) 0.393 Sex Male 126 58.3% 100 56.2% 26 68.4% Female 90 41.7% 78 43.8% 12 31.6% 0.165 Race White 162 75.0% 137 77.0% 25 65.8% Asian 4 1.9% 2 1.1% 2 5.3% Black 21 9.7% 18 10.1% 3 7.9% Hispanic 26 12.0% 18 10.1% 8 21.1% Other 2 0.9% 2 1.1% 0 0.0% 0.197 Body mass index (kg/m2) < 25 32 14.8% 25 14.0% 7 18.4% 25-30 68 31.5% 55 30.9% 13 34.2% 30-35 60 27.8% 50 28.1% 10 26.3% 35 + 56 25.9% 48 27.0% 8 21.1% 0.808 Prior abdominal surgery Yes 118 54.6% 104 58.4% 14 36.8% No 98 45.4% 74 41.6% 24 63.2% 0.015 Prior kidney surgery Yes 10 4.6% 9 5.1% 1 2.6% No 206 95.4% 169 94.9% 37 97.4% 0.518 Chronic kidney disease stage ≥ 3 Yes 45 20.8% 38 21.3% 7 18.4% No 171 79.2% 140 78.7% 31 81.6% 0.687 Charlson comorbidity index 0 138 63.9% 116 65.2% 22 57.9% 1 46 21.3% 38 21.4% 8 21.1% 2 19 8.8% 13 7.3% 6 15.8% ≥ 3 13 6.0% 11 6.2% 2 5.3% 0.412 Tumor size (cm) 2.7 (2-3.6) 2.8 (2-3.5) 2.55 (2-3.7) 0.796 Tumor laterality Left 100 46.3% 78 43.8% 22 57.9% Right 116 53.7% 100 56.2% 16 42.1% 0.114 Clinical T stage cT1a 186 86.1% 152 85.4% 34 89.5% cT1b 30 13.9% 26 14.6% 4 10.5% 0.509 RENAL Nephrometry score Low (4 to 6) 94 43.5% 76 42.7% 18 47.4% Intermediate (7 to 9) 112 51.9% 94 52.8% 18 47.4% High (≥ 10) 19 4.6% 8 4.5% 2 5.3% 0.829 TE tumor enucleation, SPN standard margin partial nephrectomy, IQR interquartile range.

Survival assessment of nephron-sparing surgery or radical nephrectomy in children with unilateral Wilms tumor receiving adjuvant chemotherapy: a retrospective cross-sectional study.

OBJECTIVE: Surgical treatment of unilateral Wilms tumor (WT) in children is controversial. In this study, we aimed to evaluate the survival and prognosis of radical nephrectomy (RN) and nephron-sparing surgery (NSS) in children with unilateral WT receiving adjuvant chemotherapy. PATIENTS AND METHODS: Data on pediatric patients with WT were collected from the Surveillance, Epidemiology, and End Results (SEER) database from 2000 to 2019. Multivariate logistic regression was used to analyze factors influencing the choice of surgical strategy. Cox proportional hazard models were used to assess factors associated with overall survival. RESULTS: We included 1,825 patients with unilateral WT (<14 years) who received adjuvant chemotherapy and surgery. Between 2000 and 2019, the percentage of patients treated with NSS increased from 4% in 2000 to 8% in 2019. There was no significant difference in 10-year overall survival between the two surgical strategies [NSS vs. RN, 93.26% (95% CI, 86.88%-100%) vs. 92.17% (95% CI, 90.75%-93.61%), p=0.98]. Patients with unilateral WTs ≤4 cm were more likely to be treated with NSS. There was no survival benefit for patients treated with RN compared with that for those treated with NSS (HR, 0.74; 95% CI, 0.29-1.86; p=0.5). CONCLUSIONS: The use of NSS in children with unilateral WT has increased over the last two decades. Tumor size is an important influencing factor for the surgical application of NSS. Patients who underwent NSS had an equivalent OS compared with the overall group of patients with unilateral tumors who received RN.

Nephrometry Scoring Systems for Nephron Sparing Surgery in Children.

The surgical decision to attempt nephron-sparing surgery (NSS) in children with renal tumors can be difficult. In adults, nephrometric tools are used for decision-making. More than 90% of low-complexity tumors are eligible for NSS, and high-complexity tumors often require total nephrectomy. We retrospectively applied those nephrometric tools [Radius, Exophytic, Nearness to the sinus or collecting system, Anterior/posterior, Location relative to polar lines (RENAL), Preoperative Aspects and Dimensions Used for an Anatomical classification (PADUA), and Renal Tumor Invasion Index (RTII) scoring systems] to the preoperative imaging of children operated for renal tumors in our institution from 2015 to 2019 and correlated them with the type of surgery. The scores were assessed by 2 independent surgeons and 1 radiologist. Forty-four tumors were removed, including 16 NSS, 38 after neo-adjuvant chemotherapy, and 6 upfront surgeries, in 30 children. More than 50% of patients in the low and medium-risk population for RENAL, PADUA, and RTII scores, and ~15% in the high-complexity categories underwent NSS. Tumors removed through NSS were significantly less complex according to each score. Interobserver reliability was good for 3 scores. The application of the RENAL, PADUA, and RTII was able to accurately classify most of the pediatric tumors, according to their complexity. These scores could help increase the indications of NSS in renal tumor surgery.

Redo nephron-sparing surgery in stage V pediatric renal tumors - A report from the SIOP/GPOH study group for renal tumors.

PURPOSE: Nephron-sparing Surgery (NSS) is the surgical treatment of choice in children with bilateral renal tumors or in syndromatic patients. With an increasing role of this surgical approach, there is also an increased number of tumor relapses after NSS. Aim of this study was to evaluate a second ("Redo-") NSS in children with relapsed renal tumors. MATERIALS AND METHODS: We retrospectively analysed patients undergoing Redo-NSS for relapsed kidney tumors between 2009 and 2021 at our institution, which represents a national reference center of the SIOP/GPOH renal tumor study group. RESULTS: Nine patients (5 girls, 4 boys) underwent Redo-NSS with resection of 15 lesions. Mean age at surgery was 58 months (12-137), mean operative time for Redo-NSS was 195 min (137-260). R0 resection status was achieved in all children. Two patients had second relapses, one of them was resected via NSS, the other child underwent tumor nephrectomy. Two patients with anaplastic relapses died from combined second relapses. Thus, 7/9 patients are alive without evidence of disease, an impaired renal function was observed in one child. Mean follow-up after Redo-NSS was 35 months (6-49). CONCLUSIONS: In renal tumor relapses, Redo-NSS can be performed with satisfactory oncological and functional results. Occurrence of diffuse anaplasia should possibly refrain from this approach. Further evaluation in international multicenter analyses are necessary for a definitive determination of Redo-NSS.

Real-time estimation of nephron activity with a linear measurement system (RENAL-MS) predicts postoperative estimated glomerular filtration rate.

OBJECTIVE: To determine whether a simple point-of-care measurement system estimating renal parenchymal volume using tools ubiquitously available could be used to replace nuclear medicine renal scintigraphy (NMRS) in current clinical practice to predict estimated glomerular filtration rate (eGFR) after nephrectomy by estimating preoperative split renal function. PATIENTS AND METHODS: We performed a retrospective review of patients who underwent abdominal cross-sectional imaging (computed tomography/magnetic resonance imaging) and mercaptoacetyltriglycine (MAG3) NMRS prior to total nephrectomy at a single institution. We developed the real-time estimation of nephron activity with a linear measurement system (RENAL-MS) method of estimating postoperative renal function via the following technique: renal parenchymal volume of the removed kidney relative to the remaining kidney was estimated as the product of renal length and the average of six renal parenchymal thickness measurements. The utility of this value was compared to the utility of the split renal function measured by MAG3 for prediction of eGFR and new onset Stage 3 chronic kidney disease (CKD) at ≥90 days after nephrectomy using uni- and multivariate linear and logistic regression. RESULTS: A total of 57 patients met the study criteria. The median (interquartile range [IQR]) age was 69 (61-80) years. The median (IQR) pre- and postoperative eGFR was 74 (IQR 58-90) and 46 (35-62) mL/min/1.73 m2 , respectively. [Correction added on 29 December 2023, after first online publication: The data numbers in the preceding sentence have been corrected.] Correlations between actual and predicted postoperative eGFR were similar whether the RENAL-MS or NMRS methods were used, with correlation using RENAL-MS being slightly numerically but not statistically superior (R = 0.82 and 0.76; P = 0.138). Receiver operating characteristic curve analysis using logistic regression estimates incorporating age, sex, and preoperative creatinine to predict postoperative Stage 3 CKD were similar between RENAL-MS and NMRS (area under the curve 0.93 vs. 0.97). [Correction added on 29 December 2023, after first online publication: The data numbers in the preceding sentence have been corrected.] CONCLUSION: A point-of-care tool to estimate renal parenchymal volume (RENAL-MS) performed equally as well as NMRS to predict postoperative eGFR and de novo Stage 3 CKD after nephrectomy in our population, suggesting NMRS may not be necessary in this setting.

The safety and effectiveness of laparoscopic off-clamp tumor evacuation versus traditional nephron-sparing surgery for large (>4 cm) sporadic renal angiomyolipomas.

BACKGROUND: Off-clamp nephron-sparing surgery (NSS) have been selectively performed in renal tumors in which the majority are T1a (<4 cm) renal caners. Less is known, however, whether off-clamp is a safe and effective option for treatment of Sporadic Renal Angiomyolipomas (RAML), especially in those >4 cm. The objective of our study was to compare the perioperative and renal function outcomes of a novel off-clamp tumor evacuation technique versus conventional laparoscopic NSS for the treatment of large sporadic RAMLs (>4 cm). METHODS: From January 2021 to June 2022, 42 patients diagnosed with RAML were prospectively randomized to receive laparoscopic standard NSS (Group 1) and off-clamp tumor evacuation (Group 2). The surgical and postoperative outcomes of both groups were compared. RESULTS: Baseline characteristics demonstrated no discernible variation between Group 1 and Group 2. Compared to Group 1, Group 2 was associated shorter operative time (92.5 vs 82.3 min, p < 0.001), elimination of warm ischemic time (22.9 vs 0 min, p < 0.001), more blood loss (92.6 vs 161.9 ml, p = 0.02), and lower short-term renal function reduction of the operated kidney (17.2% vs 9%; p < 0.001). Neither major complication nor recurrence occurred. CONCLUSION: It seems that transperitoneal laparoscopic off-clamp tumor evacuation is a feasible and safe option for the treatment of RAML, with the added benefit of preserving renal function to a greater extent than the traditional methods.

Efficacy and late kidney effects of nephron-sparing surgery in the management of unilateral Wilms tumor: a systematic review and meta-analysis.

To evaluate the efficiency and long-term renal function of nephron sparing surgery (NSS) in unilateral WT patients compared with radical nephrectomy (RN). The review was performed following Cochrane Handbook guidelines and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We searched five databases (Pubmed, Embase, Scopus, Web of Science and Cochrane) for studies reporting the efficiency and late renal function of NSS and/or RN on February 10, 2023. Comparative studies were evaluated by Risk of Bias in Non-randomized Studies of Interventions (ROBINS-I) and RoB 2.0. Assessed outcomes included survival rate, relapse rate, eGFR, renal dysfunction and hypertension. 26 studies involving 10322 unilateral WT cases underwent RN and 657 unilateral WT cases underwent NSS were enrolled. Overall effect estimates demonstrated that NSS significantly increased eGFR at follow-up (SMD, 0.38; 95% CI 0.05-0.72; p = 0.025) compared to that at diagnosis, and RN did not significantly decrease eGFR at follow-up (SMD, - 0.33; 95% CI - 0.77-0.11; p = 0.142) compared to that at diagnosis. Moreover, no significant difference was found in outcomes of survivability (OR, 1.38; 95% CI 0.82-2.32; p = 0.226), recurrence (OR, 0.62; 95% CI 0.34-1.12; p = 0.114), eGFR at follow-up (SMD, 0.16; 95% CI - 0.36-0.69; p = 0.538), renal dysfunction (OR, 0.36; 95% CI 0.07-1.73; p = 0.200) and hypertension (OR, 0.17; 95% CI 0.03-1.10; p = 0.063). Current evidence suggests that NSS is safe and effective for unilateral WT patients, because it causes better renal function and similar oncological outcomes compared with RN. Future efforts to conduct more high-quality studies and explore sources of heterogeneity is recommended.

Nephron-sparing ureteroscopic surgery vs. radical nephroureterectomy: comparable survival-outcomes in upper tract urothelial carcinoma.

PURPOSE: This study investigates the utility of ureteroscopic surgery (URS) as an alternative to radical nephroureterectomy (RNU) in managing upper tract urothelial carcinoma (UTUC), with a focus on survival outcomes and re-evaluation of current the European Association of Urology guidelines criteria. METHODS: We conducted a retrospective, multi-institutional review of 143 UTUC patients treated with URS (n = 35) or RNU (n = 108). Clinicopathological factors were analyzed, and survival outcomes were assessed using Kaplan-Meier analysis and Cox proportional-hazards models. RESULTS: The median follow-up period was 27 months. Overall survival (OS) and radiographic progression-free survival (rPFS) were comparable between the URS and RNU groups (OS: HR 2.42, 95% CI 0.63-9.28, P = 0.0579; rPFS: HR 1.82, 95% CI 0.60-5.47, P = 0.1641). URS conferred superior renal function preservation. In patients characterized by factors such as radiographically invisible lesions, negative cytology, pTa stage, low-grade tumors, and multiple lesions, the OS outcomes with URS were comparable to those with RNU as follows: radiographically invisible lesions (P = 0.5768), negative cytology (P = 0.7626), pTa stage (P = 0.6694), low-grade tumors (P = 0.9870), and multiple lesions (P = 0.8586). CONCLUSION: URS offers survival outcomes similar to RNU, along with better renal function preservation, especially in low-risk UTUC patients. These findings underscore the urgency of re-evaluating the current EAU guidelines and encourage further research into determining the ideal patient selection for URS in UTUC treatment.

RENAL nephrometry scoring system in bilateral Wilms tumor: predictive application.

AIM: This study aims to explore the application of RENAL nephrometry scoring system in bilateral Wilms tumor (BWT). METHODS: A retrospective review of patients with BWT from January 2010 to June 2022 was performed. Each kidney unit of the BWT was evaluated independently and scored according to RENAL nephrometry scoring system by 2 blinded reviewers, and reviewers were blinded to what surgery the patients ultimately had. Discrepancies were evaluated by a third reviewer to reach a consensus. Tumor anatomical characteristics were summarized and compared. RESULTS: 29 patients with 53 kidney units were included in the study. 53 kidney units included 12 (22.6%) low-complexity, 9 (17.0%) intermediate-complexity, and 32 (60.4%) high-complexity. 2 kidney units (3.8%) had tumor thrombus, and 14 (26.4%) had multiple lesions. A total of 42 kidney units (79.2%) underwent initial nephron-sparing surgery (NSS) and 11 (20.8%) underwent radical nephrectomy. Less complexity tumors were observed in the NSS group. Of the 42 kidney units undergoing initial NSS, 26 were performed in vivo and 16 ex vivo via autotransplantation. The latter group featured a higher complexity. During follow-up, 22 patients survived and 7 died, no statistically significant tumor complexity was observed between the two groups. CONCLUSIONS: The anatomical characteristics of BWT are complex. Despite this study did not indicate that the complexity correlates with prognosis, low-complexity tumors were candidates for NSS, and kidney autotransplantation provided a feasible procedure for high-complexity tumors. A refined system is required due to multiple lesions and tumor thrombus.

Minimally invasive nephron-sparing treatments for T1 renal cell cancer in patients over 75 years: a comparison of outcomes after robot-assisted partial nephrectomy and percutaneous ablation.

PURPOSE: To compare the oncological and perioperative outcomes of robot-assisted partial nephrectomy (RPN) and percutaneous thermal ablation (PTA) for treatment of T1 renal cell cancer (RCC) in patients older than 75 years. MATERIALS AND METHODS: Retrospective national multicenter study included all patients older than 75 years treated for a T1 RCC by RPN or PTA between January 2010 and January 2021. Patients' characteristics, tumor data, and perioperative and oncological outcomes were compared. RESULTS: A total of 205 patients for 209 procedures (143 RPN and 66 PTA) were included. In the PTA group, patients were older (80.4 ± 3.7 vs. 79 ± 3.7 years (p = 0.01)); frailer (ASA score (2.43 ± 0.6 vs. 2.17 ± 0.6 (p < 0.01)); and more frequently had a history of kidney surgery (16.7% [11/66] vs. 5.6% [8/143] (p = 0.01)) than in the RPN group. Tumors were larger in the RPN group (2.7 ± 0.7 vs. 3.2 ± 0.9 cm (p < 0.01)). Operation time, length of hospital stay, and increase of creatinine serum level were higher in RPN (respectively 92.1 ± 42.7 vs. 150.7 ± 61.3 min (p < 0.01); 1.7 ± 1.4 vs. 4.2 ± 3.4 days (p < 0.01); 1.9 ± 19.3% vs. 10.1 ± 23.7 (p = 0.03)). Disease-free survival and time to progression were similar (respectively, HR 2.2; 95% CI 0.88-5.5; p = 0.09; HR 2.1; 95% CI 0.86-5.2; p = 0.1). Overall survival was shorter for PTA that disappeared after Cox adjusting model (HR 3.3; 95% CI 0.87-12.72; p = 0.08). CONCLUSION: Similar oncological outcomes are observed after PTA and RPN for T1 RCC in elderly patients. CLINICAL RELEVANCE STATEMENT: Robot-assisted partial nephrectomy and percutaneous thermal ablation have similar oncological outcomes for T1a kidney cancer in patients over 75 years; however, operative time, decrease in renal function, and length of hospital stay were lower with ablation. KEY POINTS: • After adjusting model for age and ASA score, similar oncological outcomes are observed after percutaneous thermal ablation and robot-assisted partial nephrectomy for T1 renal cell cancer in elderly patients. • Operation time, length of hospital stay, and increase of creatinine serum level were higher in the robot-assisted partial nephrectomy group.

Utilizing RENAL nephrometry in pediatric patients undergoing nephron-sparing surgery for renal tumors: A single-institutional cohort.

INTRODUCTION: RENAL Nephrometry is a complexity score validated in adults with renal tumors and describes the likelihood of complication after partial nephrectomy (PN). Utilization in pediatrics has been limited. Thus, our goal is to quantify inter-rater agreement as well as determine how scores correlate with outcomes. We hypothesize that the RENAL Nephrometry Score is reproducible in children with renal tumors and is related to perioperative and post-operative complications. METHODS: All pediatric patients who underwent PN for a renal mass from 2006 to 2019 were identified. Patient data, operative details, and outcomes were aggregated. Pre-operative CT/MR imaging was anonymized and scored by 2 pediatric radiologists and 2 pediatric urologists using RENAL Nephrometry metrics. Statistical analysis utilized Fleiss' kappa and the intraclass correlation coefficient (ICC). Comparative analyses were performed based on Nephrometry Score <9 and ≥ 9. RESULTS: 28 patients undergoing 33 PN were identified. Median age at surgery was 3.2 years (IQR 1.8-4.0). There is moderate-good agreement across scorers on the domains of RENAL Nephrometry Score, with the lowest agreement noted for anterior vs posterior tumors. Comparing patients with scores <9 and ≥ 9, there was increased operative time (357 vs 267 min, p = 0.003) and LOS for those with a higher score, but no difference in the incidence of 30-day complications. CONCLUSION: RENAL Nephrometry Score is an easily reproducible complexity score for renal tumors in pediatric patients. Higher scores are associated with increased length of stay and estimated blood loss but not complications. Reporting of nephrometry scores in future publications on pediatric renal tumors should become standard in the literature.

Medial versus lateral camera port placement for robotic nephron-sparing surgery: evaluating surgical complications and outcomes.

As the growing popularity of robotic-assisted laparoscopic procedures for the treatment of renal cancer increases, there exists a variation in surgical technique among institutions and surgeons alike. One variation that exists in robotics is the anatomical placement of the camera port (medial versus lateral camera port placement). The purpose of this study is to evaluate surgical complications and outcomes in comparison to site of camera port placement during nephron-sparing surgery in an academic setting. Over a three-year period, outcomes for all robotic surgeries for renal cancer were examined. A total of 229 cases were discovered. Patient demographics and comorbidities were analyzed along with perioperative surgical data including location of camera port, surgery length, warm ischemia time, blood loss, pathological tumor margins, tumor size, length of stay and laboratory data. 134 patients had surgery performed with lateral camera port placement versus 95 patients with medial camera port placement. Operative time was significantly lower with an average operative time of 165.8 min for the lateral group versus 209.1 min in the medial group (p < 0. 0001). Warm ischemia time was also less in the lateral group with an average of 11 min versus 15.5 min for the medial group (p < 0. 0001). Blood loss was less in the lateral camera port group with an average of 158.2 mL (± 196.5 mL) versus 248.6 mL in the medial group (± 252.6) (p = 0.0040). Drain use, positive surgical margin rate, transfusion rate, conversion to radical nephrectomy, change in pre-operative versus postoperative creatinine and glomerular filtration rate and length of hospital stay did not statistically differ. Lateral camera port placement is associated with decreased operative time and warm ischemia time in this series. There may be certain laparoscopic advantages through a better visualization of surgical anatomy, thus allowing for faster extirpation of renal lesions and decrease in surgical time. These advantages may result in better long-term renal function and decreased clinical sequela from chronic kidney disease.

Advanced chronic kidney disease; A comparison between nephroureterectomy and nephron-sparing surgery for upper tract urothelial carcinoma.

PURPOSE: Renal function outcomes between radical nephroureterectomy (RNU) and nephron-sparing surgery (NSS) for upper tract urothelial carcinoma (UTUC) patients are not well established. We sought to compare the incidence and factors associated with development of advanced chronic kidney disease (CKD) between RNU and NSS and examine the role of acute kidney injury (AKI) on renal function outcomes. METHODS: We retrospectively analyzed an institutional database for patients who underwent either RNU or NSS for UTUC. Cumulative incidence of postoperative advanced CKD, defined as eGFR < 30 ml/min/1.73 m2, was compared between groups. Fine-Gray competing risk regression was used to identify predictors of advanced CKD. Locally weight scatterplot smoothing was used to assess postoperative eGFR trends. AKI events were counted, staged, and assessed for influence of progression to advanced CKD. RESULTS: Four hundred and twenty-six patients were included in analysis, with a median follow up of 6.68 years (IQR 3.4-12.2). Median preoperative eGFR was similar between the groups (NSS: 68 ml/min/1.73 m2, RNU: 65 ml/min/1.73 m2,P = 0.220). Cumulative incidence of advanced CKD was significantly lower in the NSS cohort (P = 0.009). Factors associated with advanced CKD included age, diabetes, recurrent AKI and RNU. Percent of patients with an AKI event differed between the groups (51.5% NSS, 72.7% RNU, P = <0.001), there was no between group difference in percentage of patients with recurrent AKI (25.6% NSS, 25.9% RNU, P =1). CONCLUSION: NSS provides a renal function benefit in UTUC. AKI is common among UTUC patients and recurrent AKI is a risk factor for development of advanced CKD.

Pediatric Small Renal Masses: Can Tumor Size Predict Histology and the Potential for Nephron-sparing Surgery?

PURPOSE: The majority of children with unilateral renal masses suspicious for malignancy undergo radical nephrectomy, while nephron-sparing surgery is reserved for select cases. We investigated the impact of tumor size on the probability of histology. We hypothesized that pediatric small renal masses are more likely benign or non-Wilms tumor, thus potentially appropriate for nephron-sparing surgery. MATERIALS AND METHODS: The SEER (Surveillance, Epidemiology, and End Results) database was analyzed for patients aged 0-18 years diagnosed with a unilateral renal mass from 2000-2016. Statistical analysis was performed to help determine a tumor size cut point to predict Wilms tumor and assess the predictive value of tumor size on Wilms tumor histology. Additionally, a retrospective review was performed of patients 0-18 years old who underwent surgery for a unilateral renal mass at a single institution from 2005-2019. Statistical analysis was performed to assess the predictive value of tumor size on final histology. RESULTS: From the SEER analysis, 2,016 patients were included. A total of 1,672 tumors (82.9%) were Wilms tumor. Analysis revealed 4 cm to be a suitable cut point to distinguish non-Wilms tumor. Tumors ≥4 cm were more likely Wilms tumor (OR 2.67, P ≤ .001), but this was driven by the statistical significance in children 5-9 years old. From the institutional analysis, 134 patients were included. Ninety-seven tumors (72.3%) were Wilms tumor. Tumors ≥4 cm had higher odds of being Wilms tumor (OR 30.85, P = .001), malignant (OR 6.75, P = .005), and having radical nephrectomy-appropriate histology (OR 46.79, P < .001). CONCLUSIONS: The probability that a pediatric unilateral renal mass is Wilms tumor increases with tumor size. Four centimeters is a logical cut point to start the conversation around defining pediatric small renal masses and may help predict nephron-sparing surgery-appropriate histology.

Nephron-sparing surgery for renal cell carcinoma in children and young adults: A systematic review.

OBJECTIVE: To determine the patient characteristics and role of nephron-sparing surgery (NSS) in the treatment of children and young adults with renal cell carcinoma (RCC). METHODS: A systematic search of Embase, MEDLINE, and Scopus databases was conducted in December 2021 according to Cochrane collaboration recommendations. All included manuscripts were assessed for patient characteristics and all reported outcomes for patients undergoing partial nephrectomy (PN), and radical nephrectomy (RN) outcomes were abstracted as a comparison group. Primary outcomes included surgical outcomes, overall survival, kidney outcomes. Outcomes were pooled with weighted mean and ranges. Meta-analysis was not performed given study quality. This systematic review was prospectively registered on PROSPERO (CRD42022300261). RESULTS: We found a total of 16 studies describing 119 and 559 unique patients undergoing PN and RN, respectively, with a mean age of 12.2 years and mean follow-up of 59.1 months. The mean tumor size for patients undergoing PN was 3.5 cm. Of the 113 patients undergoing PN with available data, 109 were alive at follow-up (98%). No studies reported long-term kidney outcomes, and four studies reported surgical outcomes. All studies had at least moderate risk of bias. CONCLUSIONS: The use of NSS in children and young adults with RCC is feasible in selected patients. However, small sample sizes, confounding, and low study quality limit clinical recommendation on NSS in this population. There are significant opportunities for future research on the use of NSS in RCC, especially with systematic reporting of oncological, kidney, and surgical outcomes.

Impact of Blood Loss on Renal Function and Interaction with Ischemia Duration after Nephron-Sparing Surgery.

OBJECTIVES: Nephron-sparing surgery (NSS) exposes the kidney to ischemia-reperfusion injury. Blood loss and hypotension are also associated with kidney injury. We aimed to test the hypothesis that, during NSS, both ischemia duration and blood loss significantly affect postoperative renal function and that their effects interact. METHODS: Consecutive patients undergoing NSS were enrolled. The primary endpoint was renal function expressed as the absolute delta between preoperative and postoperative peak creatinine. We developed a generalized linear model with the ischemia duration and absolute hemoglobin difference as independent variables, their interaction term, and the RENAL score. The model was than expanded to include a history of hypertension (as a proxy for hypotension susceptibility) and related interaction terms. Further, we described the perioperative and mid-term oncological outcomes. RESULTS: A total of 478 patients underwent NSS, and 209 (43.7%) required ischemia for a mean of 10.9 min (SD 8). Both the ischemia duration (partial eta 0.842, p = 0.006) and hemoglobin difference (partial eta 0.933, p = 0.029) significantly affected postoperative renal function, albeit without evidence of a significant interaction (p = 0.525). The RENAL score also significantly influenced postoperative renal function (p = 0.023). After the addition of a previous history of hypertension, the effects persisted, with a significant interaction between blood loss and a history of hypertension (p = 0.02). CONCLUSIONS: Ischemia duration and blood loss had a similar impact on postoperative renal function, albeit without potentiating each other. While the surgical technique and ischemia minimization remain crucial to postoperative kidney function, increased awareness of conscious hemodynamic management appears warranted.

Nephron sparing surgery outcomes in Wilms' tumor: is it ready for primetime?

PURPOSE: Radical nephrectomy is the gold standard in Wilms tumor (WT) treatment and is combined with adjuvant treatment in early stage disease or performed after neo adjuvant therapy in advanced disease. With the development of novel adjuvant and neoadjuvant therapeutic strategies, there is increasing interest in organ preserving procedures in several adult malignancies. Potential long-term complications of living with a single kidney include hyperfiltration syndrome, hypertension, and fluid retention. If NSS (Nephron Sparing Surgery) were to be adopted for the treatment of WT it would be necessary to preserve the gains in Overall Survival (OS) seen with current treatment protocols. With this in mind we undertook a study of outcomes of NSS performed in the USA using a large population-based registry. METHODS: We retrospectively queried the SEER Research Plus 18-registries Database 2010-2018 for patients 18 years old or younger with Wilms tumor as determined by ICD-O-3 code 8960. Clinical and demographic data was extracted, and statistical analysis was performed in GraphPad PRISM 9 with bivariate analysis and log-rank analysis to determine survival. RESULTS: 1087 patients with Wilms tumor were identified. 73 (6.72%) underwent nephron-sparing surgery. The final cohort consisted of 45 patients (64%) who underwent unilateral NSS and 25 patients (36%) who underwent bilateral NSS. Three were excluded from analysis due to non-renal origin of tumor. Mean age was 3.214 years (std dev 3.807). Demographics were similar between the groups, apart from younger age associated with bilateral tumor (p = 0.0441). No differences were found between radiation use (p = 0.4280), chemotherapy use (p = 0.5479), tumor size (p = 0.2186), positive regional lymph nodes (p = 0.707). Log-rank analysis demonstrated that cancer-specific survival was not significantly different between unilateral and bilateral NSS or radical nephrectomy (p = 0.4539). CONCLUSION: NSS may preserve renal function long-term, an important consideration in the pediatric population. Prospective study is necessary to select the appropriate patient subsets who may benefit from NSS in WT.