Nephrometry Systems Research Articles

SC45 - Retrospective analysis of three nephrometry systems in predicting outcomes of renal percutaneous cryoablation

SC45 - Retrospective analysis of three nephrometry systems in predicting outcomes of renal percutaneous cryoablation

MP61-15 PREDICTING RENAL FUNCTIONAL OUTCOMES AFTER PARTIAL NEPHRECTOMY: A COMPARISON OF NEPHROMETRY SYSTEMS

You have accessJournal of UrologyKidney Cancer: Epidemiology & Evaluation/Staging/Surveillance III (MP61)1 Sep 2021MP61-15 PREDICTING RENAL FUNCTIONAL OUTCOMES AFTER PARTIAL NEPHRECTOMY: A COMPARISON OF NEPHROMETRY SYSTEMS Jillian Egan, Sandeep Gurram, Jeunice Owens-Walton, Winston Li, Alexis Rompre-Brodeur, Michael Ahdoot, Nitin Yerram, Patrick Gomella, Heather Chalfin, W. Marston Linehan, and Mark W. Ball Jillian EganJillian Egan More articles by this author , Sandeep GurramSandeep Gurram More articles by this author , Jeunice Owens-WaltonJeunice Owens-Walton More articles by this author , Winston LiWinston Li More articles by this author , Alexis Rompre-BrodeurAlexis Rompre-Brodeur More articles by this author , Michael AhdootMichael Ahdoot More articles by this author , Nitin YerramNitin Yerram More articles by this author , Patrick GomellaPatrick Gomella More articles by this author , Heather ChalfinHeather Chalfin More articles by this author , W. Marston LinehanW. Marston Linehan More articles by this author , and Mark W. BallMark W. Ball More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002101.15AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Various nephrometry systems (NS) have been created to predict perioperative outcomes following nephron-sparing surgery (NSS). The aim of this study was to examine RENAL, PADUA, centrality index (C-index) and contact surface area (CSA) scores and their association with renal functional outcomes (RFO) after partial nephrectomy (PN). METHODS: An IRB-approved, prospectively maintained registry was queried for patients who underwent PN for a single renal mass from 2008-2019 and had 12-month (mo) postoperative renal function follow-up. Computerized tomography or magnetic resonance imaging was reviewed to obtain RENAL, PADUA, C-index and CSA for each patient. Postoperative renal function was measured by serum creatinine and estimated glomerular filtration rate (eGFR) or by 99-mTC-mercaptoacetyltriglycine renogram (MAG3). Correlations between NS and RFO were analyzed to determine their predictive capabilities. RESULTS: 122 patients underwent PN; 13 (10.5%), 73 (60%), 36 (29.5%) were under cold, warm, and no ischemia, respectively. 72 of these patients had postoperative MAG3 scan. Median age was 48 years [Interquartile range (IQR) 38-56]. Median tumor size was 3.2 cm [IQR 2.6-4.5]. Median baseline GFR was 84 ml/min [IQR 72-102 ml/min]. Median percent decrease in 12 mo GFR was 4.3% [IQR -6.8-14.7%]. On univariate analysis, only high PADUA class was associated with percent decrease in 12 mo GFR (13.2%, p=0.012). High RENAL class and CSA were associated with postoperative renal function changes detected by MAG3 (10.5%, p =0.002 and 0.10%, p=0.004). On multivariate analysis, only high PADUA class was associated with percent decrease in 12-mo GFR (11.7%, p=0.03) when controlling for EBL, baseline GFR, and ischemia type (warm vs. cold vs. no ischemia). CONCLUSIONS: This study demonstrates the variability in the ability of different NS to predict long-term RFO. PADUA NS appears to be most predictive of postoperative renal function following PN. Further study is needed to determine association of NS with other perioperative outcomes. Source of Funding: None © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e1088-e1089 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Jillian Egan More articles by this author Sandeep Gurram More articles by this author Jeunice Owens-Walton More articles by this author Winston Li More articles by this author Alexis Rompre-Brodeur More articles by this author Michael Ahdoot More articles by this author Nitin Yerram More articles by this author Patrick Gomella More articles by this author Heather Chalfin More articles by this author W. Marston Linehan More articles by this author Mark W. Ball More articles by this author Expand All Advertisement Loading ...

P0601 - Outcomes of 10 years’ experience of percutaneous cryoablation for the treatment of cT1 renal tumour presented according to RENAL, PADUA and ABLATE nephrometry systems

P0601 - Outcomes of 10 years’ experience of percutaneous cryoablation for the treatment of cT1 renal tumour presented according to RENAL, PADUA and ABLATE nephrometry systems

Assessment of the complexity of nephron-sparing surgery of kidney tumors

The work was aimed at evaluating the influence of a number of criteria related to the tumor itself and the general characteristics of the patient on the complexity of nephron-sparing surgery and developing an original comprehensive methodology for assessing the complexity of the nephron-sparing surgery of kidney tumors. We evaluated the criteria for the operation complexity taking into account the results of nephron-sparing surgery treatment of 701 patients with kidneys tumors. The creation of an original scale for assessing the complexity of nephron-sparing surgery is not an alternative to the most popular nephrometry systems in the world, but it reflects current trends in the development of kidney tumors treatment – using nephron-sparing surgery for the most complex tumors (for intravenous invasion, multifocal tumors, tumor localization in the kidney sinus, and relapse of the neoplasm) in patients with imperative indications. Such a scale for assessing the complexity of nephron-sparing surgery allowed us considering not only new factors related to the properties of the tumor, but also individual characteristics of the patient.

The role of RENAL, PADUA, C-index, CSA nephrometry systems in predicting ipsilateral renal function after partial nephrectomy

BackgroundFunctional outcome is an important issue in nephron-sparing surgery. Various nephrometries have been developed to predict renal function preservation. The aim of this study was to examine the applicability of R.E.N.A.L., PADUA, C-index, and mathematical tumor contact surface area (CSA) in predicting ipsilateral renal function after partial nephrectomy using radio-isotope scans.MethodsWe performed this retrospective study in patients who underwent partial nephrectomy between May 2013 and April 2017, and used abdominopelvic computerized tomography or magnetic resonance imaging to obtain R.E.N.A.L., C-index, and CSA. Renal function was measured by 99mTc mercaptoacetyltriglycine (MAG3). We evaluated correlations between nephrometries and perioperative parameters, and comparatively analyzed different nephrometries to determine the predictive ability in the percent change of effective renal plasma flow of the affected kidney.ResultsThree, two, and 35 patients received partial nephrectomy in open, laparoscopic, and robotic approaches, respectively. The median (IQR) tumor size was 3.13 (2.4) cm. The median (IQR) R.E.N.A.L., PADUA, C-index, and CSA scores were 7 (3), 8 (2), 2.01 (1.87), and 14.14 (19.25) cm2, respectively. Spearman correlation analysis showed that four nephrometries were correlated with each other. The strongest correlations were between CSA and C-index (coefficient: − 0.885, p < 0.001), followed by R.E.N.A.L. and PADUA (coefficient: 0.778, p < 0.001). Ischemia time was significantly correlated with R.EN.A.L. (coefficient: 0.35, p = 0.025), PADUA (coefficient: 0.42, p = 0.007), C-index (coefficient: − 0.45, p = 0.004), and CSA (coefficient: 0.41, p = 0.009). In multivariate analysis, PADUA significantly affected ischemia time (p = 0.04). The percent change in effective renal plasma flow (PCE) of the operated kidney was correlated with PADUA (coefficient: 0.48 p = 0.002), C-index (coefficient: − 0.74, p < 0.001), and CSA (coefficient: 0.75, p < 0.001). Only CSA and C-index independently affected PCE (both p < 0.05) in multivariate analysis. In ROC curve analysis, both C-index and CSA could predict 20% change in effective renal plasma flow (AUC: 0.91 vs 0.86, p = 0.2) of the affected kidney.ConclusionsWe suggest using PADUA to evaluate surgical complexity and ischemia time. Regarding the accuracy of the prediction of post-operative ipsilateral renal function, both CSA and C-index outperformed R.E.N.A.L. and PADUA nephrometries.

Interobserver Agreement of the Estimated Contact Surface Area System for Renal Masses.

Nephrometry scores have been designed to assist in standardization of renal masses before nephron-sparing surgery. Estimated contact surface area (eCSA) has been recently described. However, its reproducibility between raters has not been rigorously explored. Our aim was to examine the reproducibility of eCSA and Radius, Exophytic, Nearness, Anterior, Line (RENAL) score (RS) nephrometry systems for renal masses by studying the interobserver agreement between 4 raters. We reviewed the cross-sectional images (computed tomography, magnetic resonance imaging) of patients who underwent nephron-sparing surgery (open, laparoscopic, and robotic). Four urologists independently scored the renal tumors according to the eCSA and RS systems. Scoring was done separately for each nephrometry system. Interobserver agreement was assessed for total scores and separate components of each system by calculating the intraclass correlation coefficient (ICC). Ninety patients were scored to achieve power of 83% with α= 0.05. eCSA and RS demonstrated excellent interobserver agreement (ICC= 0.89 for both). The radius component of eCSA and RS had the highest ICC (0.97 and 0.9, respectively) compared with the other components. Location and anterior/posterior components of RS showed poor interobserver correlation (ICC= 0.69 and 0.50, respectively). Maximal difference in RS complexity group assignment was 1 of 43 (47.8%) of cases. eCSA has excellent interobserver agreement, similar to RS. Directly measurable anatomic variables have better interobserver correlation compared with qualitative variables. These results strengthen the applicability of eCSA as a surgical complexity metric for renal surgery.

Peritumoral Artery Scoring System: a Novel Scoring System to Predict Renal Function Outcome after Laparoscopic Partial Nephrectomy

The present study aimed to assess the impact of peritumoral artery characteristics on renal function outcome prediction using a novel Peritumoral Artery Scoring System based on computed tomography arteriography. Peritumoral artery characteristics and renal function were evaluated in 220 patients who underwent laparoscopic partial nephrectomy and then validate in 51 patients with split and total glomerular filtration rate (GFR). In particular, peritumoral artery classification and diameter were measured to assign arteries into low, moderate, and high Peritumoral Artery Scoring System risk categories. Univariable and multivariable logistic regression analyses were then used to determine risk factors for major renal functional decline. The Peritumoral Artery Scoring System and four other nephrometry systems were compared using receiver operating characteristic curve analysis. The Peritumoral Artery Scoring System was significantly superior to the other systems for predicting postoperative renal function decline (p < 0.001). In receiver operating characteristic analysis, our category system was a superior independent predictor of estimated glomerular filtration rate (eGFR) decline (area-under-the-curve = 0.865, p < 0.001) and total GFR decline (area-under-the-curve = 0.796, p < 0.001), and split GFR decline (area-under-the-curve = 0.841, p < 0.001). Peritumoral artery characteristics were independent predictors of renal function outcome after laparoscopic partial nephrectomy.

COMPARISON OF NEPHROMETRIC SYSTEMS IN PARTIAL NEPHRECTOMY FOR RENAL CELL CARCINOMA

Evaluation of efficacy of using nephrometry scores was performed on our own cohort of patients. Correlation between them and clinical variables was studied. All nephrometry scores - RENAL, PADUA and C-index - correlate significantly with ischemia time during partial nephrectomy, but not with total operative time. Kidney resection for intermediate and high complexity tumors caused chronic kidney disease (CKD) de novo or CKD upstaging more often than resection for low complexity tumors. Low complexity tumors on RENAL and PADUA were characterized by significantly lower renal parenchyma ischemia time required for resection. Complications of partial nephrectomy were observed only in groups with intermediate and high tumor complexity, while differences between intermediate and high complexity seemed practically insignificant. Nephrometry systems are useful in clinical practice, but require further improvement.

New-generation nephrometry systems: head-to-head comparison of tumor contact surface area and resected and ischemic volume

ObjectivesWe propose a calculus-based formula to calculate contact surface area (CSA). We examined the correlation of CSA and renal volume loss and the predictability for renal function after partial nephrectomy (PN). Materials and methodsWe conducted a retrospective study in patients who underwent PN between January 2012 and December 2014. Based on abdominopelvic computed tomography and magnetic resonance imaging, we calculated the CSA with the formula: 2 × π × r × d; where r = radius and d = depth, while resected and ischemic volume (RAIV) was determined by the equation [2w2 + 3w(r + d) + 6rd] × w × π⁄3, where w = width of parenchymal ischemia and resection, r = radius, and d = depth. We evaluated the correlation between CSA, RAIV, and perioperative parameters. We compared the ability of CSA and RAIV to predict the reduction in renal function. ResultsThere were 35, 26, and 45 patients receiving open, laparoscopic, or robot-assisted PN, respectively. The mean ± standard deviation CSA was 30.7 ± 26.1 cm2, and the mean ± standard deviation RAIV was 19.1 ± 14.4 cm3. In Spearman correlation analysis, we found that CSA and RAIV were highly correlated (coefficient: 0.99, p < 0.001). In univariate analysis, body mass index (p = 0.02), estimated blood loss (p = 0.001), RAIV (p < 0.001), and CSA (p < 0.001) significantly affected postoperative renal function (PRF). In receiver operating characteristic curve analysis, both CSA and RAIV had good ability to predict >10% change in estimated glomerular filtration rate (area under the curve: 0.86 vs. 0.87). There was no significant difference in area under the curve between CSA and RAIV. The area difference in PCE10 was 0.002 (p = 0.51). ConclusionCSA and RAIV were correlated with several perioperative outcomes and affected PRF. The ability to predict PRF between CSA and RAIV was nearly identical. CSA was simpler to use, and may possess less interobserver variability in comparison with RAIV. Therefore, we believe that CSA can represent renal parenchymal loss.

MP11-13 PREDICTORS OF VOLUME LOSS AFTER ROBOTIC PARTIAL NEPHRECTOMY: INFLUENCE OF TUMOR LOCATION BASED ON VASCULAR ANATOMY

INTRODUCTION AND OBJECTIVES: Current nephrometry systems describe polar location as a distance relative to a horizontal plane crossing the center of the kidney. Our goal was to evaluate volume loss using a new tumor location classification system based on vascular patterns. METHODS: Between 2008 and 2014, 73 consecutive patients with preand postoperative CT imaging were identified who underwent robotic partial nephrectomy by a single surgeon with a two-layer sliding clip renorrhaphy for presumed renal cell carcinoma. Threedimensional renal models were constructed using a semi-automatic segmentation algorithm in a slice-by-slice method. The primary outcome was percent volume loss from preto postoperative scan. Tumor location was defined as being located either in or out of the vascular zone, which was defined as a 90 wedge with origin at the center of the renal hilum (see figure). Tumor contact surface area and RENAL nephrometry were calculated as previously described. Multiple linear regressions were performed to find predictors of percent volume loss. RESULTS: Median (range) patient age, body mass index, and warm ischemia time were 65.6years (18e85), 28 (21e50), and 18.5minutes (0e33), respectively. The median (range) tumor diameter and contact surface area were 2.8cm2 (1e9) and 13.8cm2 (0.9-160), respectively. Twenty-six (43%) were were RENAL 7 and above. Both postoperative pseudoaneurysms were associated with tumors located in the vascular zone. There were no urinary leaks. On univariate analysis, location in the vascular zone (22.5 vs. 12.0cm3, p<0.001), tumor diameter (p<0.001), warm ischemia time (p1⁄40.002), RENAL location (p1⁄40.01), overall RENAL score (p1⁄40.02), and percent endophytic (p1⁄40.04) were predictors of percent volume loss. Tumor diameter and contact surface area were strongly correlated (Pearson1⁄40.83). On multivariable linear regression, only tumor diameter (b1⁄4-5.9%, p1⁄40.01) and vascular zone (b1⁄4-11.8%, p<0.001) were found to be independent predictors. Contact surface area was not a predictor of volume loss on univariable (p1⁄40.10) or multivariable (p1⁄40.15) analysis. CONCLUSIONS: Location within the central 90 vascular zone and tumor diameter are both predictors of volume loss after partial nephrectomy and may be helpful during surgical planning in patients with chronic kidney disease. Source of Funding: none

MP44-15 ANATOMICAL SCORING SYSTEM FOR ASSESSING PARTIAL NEPHRECTOMY TECHNICAL COMPLEXITY

You have accessJournal of UrologyKidney Cancer: Evaluation and Staging II1 Apr 2015MP44-15 ANATOMICAL SCORING SYSTEM FOR ASSESSING PARTIAL NEPHRECTOMY TECHNICAL COMPLEXITY Massimiliano Spaliviero, Bing Ying Poon, Christoph A. Karlo, Giuliano B. Guglielmetti, Pier Luigi Di Paolo, Felix Campos-Juanatey, Melanie L. Bernstein, Daniel D. Sjoberg, Paul Russo, Jonathan A. Coleman, Oguz Akin, and Karim A. Touijer Massimiliano SpalivieroMassimiliano Spaliviero More articles by this author , Bing Ying PoonBing Ying Poon More articles by this author , Christoph A. KarloChristoph A. Karlo More articles by this author , Giuliano B. GuglielmettiGiuliano B. Guglielmetti More articles by this author , Pier Luigi Di PaoloPier Luigi Di Paolo More articles by this author , Felix Campos-JuanateyFelix Campos-Juanatey More articles by this author , Melanie L. BernsteinMelanie L. Bernstein More articles by this author , Daniel D. SjobergDaniel D. Sjoberg More articles by this author , Paul RussoPaul Russo More articles by this author , Jonathan A. ColemanJonathan A. Coleman More articles by this author , Oguz AkinOguz Akin More articles by this author , and Karim A. TouijerKarim A. Touijer More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.1557AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES We developed a surgical complexity score system based on the arterial vascular anatomy of the kidney in an attempt to overcome the limitations of available nephrometry scoring systems including inconsistent ability to predict clinical outcomes of partial nephrectomy. METHODS Contrast-enhanced computed tomography images of 179 patients who underwent partial nephrectomy were independently scored by 4 readers. According to the order of vessels involved by the tumor or needed to be transected during partial nephrectomy, assigned score was 1 for interlobular and arcuate arteries; 2 for interlobar arteries; 3S for segmental arteries; and 3H for renal hilum (Fig. 1). The Interobserver variability was assessed with kappa values and percentage of exact matches between each pairwise combination of the 4 readers. Spearman correlation was used to evaluate the association between scores of the most experienced reader (reference score) and ischemia time, estimated blood loss, incidence of urinary fistula within 30 days, and percent change in eGFR from baseline to 6 weeks and 6 months after surgery. RESULTS All pairwise comparisons of readers' score assignments were significantly correlated (all p <0.0001) with an average kappa of 0.545 across all reader pairs. The average proportion of exact matches was 69%. Spearman correlations between the complexity score system and surgical outcomes (Table 1) showed significant levels of correlation between the reference category assignments and ischemia time (p <0.0001, coefficient = 0.435), estimated blood loss (p = 0.008, coefficient = 0.198), and urinary fistula formation (p=0.008, coefficient of 0.196). CONCLUSIONS Similar to other nephrometry scoring systems, our anatomic system is associated with the surgical complexity and perioperative morbidity of partial nephrectomy. However, its intuitiveness and ease of learning is highly favorable compared to existing nephrometry systems. While these initial results are promising, further evaluation of our new scoring system and direct comparisons to the existing nephrometry are required. Category 1 (n = 13) Category 2 (n = 62) Category 3S (n = 69) Category 3H (n = 35) Estimated Blood Loss, mL, mean (95% CI) 169 (107, 232) 256 (195, 316) 285 (230, 339) 377 (253, 501) Ischemia Time, min, mean (95% CI) 17 (7, 25) 29 (26, 33) 39 (35, 42) 43 (37, 49) Urinary Fistula Formation, % (95% CI) 0 (0, 24.7) 3.2 (0.4, 11.2) 8.7 (3.3, 18.0) 17.1 (6.6, 33.6) % Change in postoperative eGFR by 6±4 weeks, n=100, % (95% CI) -3.6 (-15.2, 7.9) -5.2 (-9.6, -0.8) -7.6 (-12.1, -3.1) -0.3 (-17.6, 17.1) % Change in postoperative eGFR by 6±1 month, n=49, % (95% CI) -14.3 (-193.4, 164.8) -3.0 (-16.1, 10) -2.0 (-10.1, 6.1) -6.9 (-16.4, 2.6) © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e532 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Massimiliano Spaliviero More articles by this author Bing Ying Poon More articles by this author Christoph A. Karlo More articles by this author Giuliano B. Guglielmetti More articles by this author Pier Luigi Di Paolo More articles by this author Felix Campos-Juanatey More articles by this author Melanie L. Bernstein More articles by this author Daniel D. Sjoberg More articles by this author Paul Russo More articles by this author Jonathan A. Coleman More articles by this author Oguz Akin More articles by this author Karim A. Touijer More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Novel kidney segmentation system to describe tumour location for nephron-sparing surgery.

To propose a novel system based on segmental renal anatomy for objectively reporting location of clinical T1 masses for nephron-sparing surgery. The kidney was subdivided into 12 standard segments, based on the computed tomography images. In 103 patients (105 cT1 tumours), three blinded radiologists (A, B, and C) prospectively reported segmental tumour location, size, and tumour-feeding arteries. Baseline, peri-operative, and post-operative data of 98 patients who underwent partial nephrectomy (PN) were prospectively collected, and the correlation between segmental tumour location and peri-operative data was evaluated. Kappa statistics were used to measure the inter-observer agreements. Tumour location could be assigned to the defined renal segment in all cases. Median tumour size was 2.8 cm (range 0.6-5.8). Inter-observer concordance was as follows: A versus B 0.82 (95% CI 0.74-0.90); A versus C 0.89 (95% CI 0.83-0.95); and B versus C 0.84 (95% CI 0.76-0.92). First, second, third, and fourth segments were involved by the tumour in 23, 39, 17, and 21% of cases, respectively. Number of segments involved by the tumour correlated with tumour size (p = 0.007), number of tumour-feeding arteries (p = 0.001), estimated blood loss during PN (p = 0.03), and trended towards higher post-operative complication rate (p = 0.07). Tumour-feeding arteries were identifiable in 80 patients (76%). Kidney segmentation (KS) system is an objective and reproducible radiologic method of universally reporting tumour location according to 12 renal segments. By adding descriptive information on tumour characteristics in candidates for nephron-sparing surgery, this novel KS system could serve as an adjunct to current nephrometry systems.

Interobserver variability of R.E.N.A.L., PADUA, and centrality index nephrometry score systems.

To assess interobserver variability of R.E.N.A.L., preoperative aspects and dimensions used for an anatomical classification system (PADUA), and centrality index (C-Index) systems among observers with varying degrees of clinical experience and each system's subscale correlation with surgical outcome metrics. Computed tomography images of 90 patients who underwent open, laparoscopic, or robot-assisted laparoscopic partial nephrectomy were scored by one radiology fellow, two urology fellows, one radiology resident, and one secondary school student. Agreement among readers was determined calculating intraclass correlation coefficients. Associations between radiology fellow scores (reference standard as reader with greatest clinical experience), ischemia time, and percent change in postoperative estimated glomerular filtration rate (eGFR) were evaluated using Spearman's correlation. Agreement using C-Index method (ICC=0.773) was higher than with PADUA (ICC=0.677) or R.E.N.A.L (ICC=0.660). Agreement between reference and secondary school student was lower than with other physicians, although the differences were not statistically significant. The reference's scores were significantly (p<0.05) associated with ischemia time on all three scoring systems and with percent change in eGFR at 6weeks using C-Index (p=0.016). Tumor size, nearness to sinus, and location relative to polar lines (R.E.N.A.L.) and tumor size, renal sinus involvement, and collecting system involvement (PADUA) correlated with ischemia time (all p≤0.001). No R.E.N.A.L. or PADUA subscales significantly correlated with percent change in postoperative eGFR. Clinical experience reduces interobserver variability of existing nephrometry systems though not significantly and less so when using directly measureable anatomic variables. Consistently, only measures of tumor size and distance to intrarenal structures were useful in predicting clinically relevant outcomes.

A Novel Mathematical Model to Predict the Severity of Postoperative Functional Reduction before Partial Nephrectomy: The Importance of Calculating Resected and Ischemic Volume

Preoperatively predicting postoperative kidney function is an essential step to achieve improved renal function and prevent chronic kidney disease. We introduce a novel formula especially to calculate resected and ischemic volume before partial nephrectomy. We examined whether resected and ischemic volume would have value for predicting postoperative renal function. We performed a retrospective cohort study in 210 patients who underwent robotic partial nephrectomy between September 2006 and October 2013 at a tertiary cancer care center. Based on abdominopelvic computerized tomography and magnetic resonance imaging we calculated resected and ischemic volume by the novel mathematical formula using integral calculus. We comparatively analyzed resected and ischemic volume, and current nephrometry systems to determine the degree of association and predictability regarding the severity of the postoperative functional reduction. On multivariable analysis resected and ischemic volume showed a superior association with the absolute change in estimated glomerular filtration rate/percent change in estimated glomerular filtration rate (B = 6.5, p = 0.005/B = 6.35, p = 0.009). The ROC AUC revealed accurate predictability of resected and ischemic volume on the stratified event of an absolute change in estimated glomerular filtration rate/event of percent change in estimated glomerular filtration rate compared to 3 representative nephrometry systems. The calibration plot of this model was excellent (close to the 45-degree line) within the whole range of predicted probabilities. We report a method of preoperatively calculating resected and ischemic volume with a novel formula. This method has superior correlation with the absolute and percent change in estimated glomerular filtration rate compared to current nephrometry systems. The predictive model achieved a strong correlation for the absolute and percent change in estimated glomerular filtration rate.

Correlations of Tumor Size, RENAL, Centrality Index, Preoperative Aspects and Dimensions Used for Anatomical, and Diameter-axial–polar Scoring With Warm Ischemia Time in a Single Surgeon's Series of Robotic Partial Nephrectomy

To evaluate the association of tumor size, renal nephrometry systems (RNSs), including RENAL, centrality index (C-index), preoperative aspects and dimensions used for anatomical, and diameter-axial-polar scoring, and individual categories of these RNSs with warm ischemia time (WIT). A single surgeon's series of robotic partial nephrectomy patients for whom RNS was available were identified from 2012 to 2013. Spearman's correlation was used to evaluate associations between the RNSs and individual categories and WIT. Analysis was performed based on 69 patients with a median tumor size of 3.5 cm (interquartile range 2.6-4.2). Overall, each scoring system and tumor size were found to have a statistically significant association with the WIT, with the C-index system exhibiting the strongest correlation (coefficient: -0.609, P <.001), which was confirmed in the series beyond the surgeon's learning curve. In the subgroup of relatively small renal masses (<3 cm), there was a statistically significant association between the C-index, preoperative aspects and dimensions used for anatomical, and diameter-axial-polar systems with WIT. However, for tumors >3 cm, none of the RNSs was found to have a statistically significant correlation with WIT, except for the tumor size (coefficient: 0.354, P = .027). For subcategories, axial scoring was found to have a consistent statistically significant correlation with WIT. Overall, each RNS and tumor size strongly correlated with WIT in patients undergoing robotic partial nephrectomy. However, the RNS outperformed tumor size in small (<3 cm) renal masses with an optimal discriminating power, whereas for relatively larger (>3 cm) tumors, WIT was significantly dependent on tumor size, and every centimeter may count.

Editorial Comment

The development of chronic kidney disease is associated with an increased risk of cardiovascular events and all-cause mortality in large population-based studies. 1 Sun M. Trinh Q.D. Bianchi M. et al. A non-cancer-related survival benefit is associated with partial nephrectomy. Eur Urol. 2012; 61: 725-731 Abstract Full Text Full Text PDF PubMed Scopus (102) Google Scholar , 2 Go A.S. Chertow G.M. Fan D. et al. Chronic kidney disease and the risks of death, cardiovascular events, and hospitalization. N Engl J Med. 2004; 351: 1296-1305 Crossref PubMed Scopus (8722) Google Scholar , 3 Levey A.S. Coresh J. Chronic kidney disease. Lancet. 2012; 379: 165-180 Abstract Full Text Full Text PDF PubMed Scopus (1212) Google Scholar Therefore, preservation of renal function remains an important consideration for patients undergoing renal surgery. The determinants of renal function after partial nephrectomy (PN) remain controversial and clinically relevant. 4 Thompson R.H. Lane B.R. Lohse C.M. et al. Renal function after partial nephrectomy: effect of warm ischemia relative to quantity and quality of preserved kidney. Urology. 2012; 79: 356-360 Abstract Full Text Full Text PDF PubMed Scopus (272) Google Scholar The quantity and quality of renal parenchymal preservation and the ischemic interval likely impact functional recovery after PN. 4 Thompson R.H. Lane B.R. Lohse C.M. et al. Renal function after partial nephrectomy: effect of warm ischemia relative to quantity and quality of preserved kidney. Urology. 2012; 79: 356-360 Abstract Full Text Full Text PDF PubMed Scopus (272) Google Scholar , 5 Thompson R.H. Lane B.R. Lohse C.M. et al. Every minute counts when the renal hilum is clamped during partial nephrectomy. Eur Urol. 2010; 58: 340-345 Abstract Full Text Full Text PDF PubMed Scopus (537) Google Scholar Correlations of Tumor Size, RENAL, Centrality Index, Preoperative Aspects and Dimensions Used for Anatomical, and Diameter-axial–polar Scoring With Warm Ischemia Time in a Single Surgeon's Series of Robotic Partial NephrectomyUrologyVol. 83Issue 5PreviewTo evaluate the association of tumor size, renal nephrometry systems (RNSs), including RENAL, centrality index (C-index), preoperative aspects and dimensions used for anatomical, and diameter-axial-polar scoring, and individual categories of these RNSs with warm ischemia time (WIT). Full-Text PDF

MP59-13 DOES THE RENAL NEPHROMETRY SYSTEM HAVE ITS OWN INDICATION IN PREDICTING SURGICAL OUTCOMES?--CORRELATION OF TUMOR SIZE, R.E.N.A.L., C-INDEX, PADUA AND DAP SCORING WITH WARM ISCHEMIA TIME IN A SINGLE SURGEON'¯S SERIES OF ROBOTIC PARTIAL NEPHRECTOMY

You have accessJournal of UrologyKidney Cancer: Localized IV1 Apr 2014MP59-13 DOES THE RENAL NEPHROMETRY SYSTEM HAVE ITS OWN INDICATION IN PREDICTING SURGICAL OUTCOMES?--CORRELATION OF TUMOR SIZE, R.E.N.A.L., C-INDEX, PADUA AND DAP SCORING WITH WARM ISCHEMIA TIME IN A SINGLE SURGEON'¯S SERIES OF ROBOTIC PARTIAL NEPHRECTOMY Linhui Wang, Zhenjie Wu, Huamao Ye, Mingmin Li, and Yinghao Sun Linhui WangLinhui Wang More articles by this author , Zhenjie WuZhenjie Wu More articles by this author , Huamao YeHuamao Ye More articles by this author , Mingmin LiMingmin Li More articles by this author , and Yinghao SunYinghao Sun More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.1809AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail Introduction and Objectives There remains a paucity of sound evidence validating which of the renal nephrometry systems (RNSs), or which subcategories of the RNS are more strongly related to the ischemia time, or whether any truly performs better than simple using tumor size. This study is to evaluate the association of tumor size, the RNS, including R.E.N.A.L., C-index, PADUA and DAP scoring, and individual categories of these RNS with warm ischemia time (WIT) in patients undergoing robotic partial nephrectomy (RPN). Methods A single surgeon's series of RPN patients for whom RNS was available were identified from Mar 2012 to Sept 2013. Spearman's correlation was used to evaluate associations between the RNSs as well as individual categories and the WIT. Results Analysis was performed based on 69 patients with a median tumor size of 3.5 cm (IQR 2.6- 4.2). Overall, each scoring system as well as tumor size was found to have a statistically significant association with the WIT, with the C-index system exhibited the strongest correlation (p < 0.001), which were confirmed in the series beyond the surgeon's learning curve. In the subgroup of relatively small renal masses (<3 cm), there was a statistically significant association between the C-index, PADUA and DAP systems with WIT. However, for tumors >3 cm, none of the RNSs was found to have a statistically significant correlation with WIT, except for the tumor size (p =0.027). For subcategories, axial scoring was found to have a consistent statistically significant correlation with WIT. Retrospective design, single center study with a small number of patients were the major limitations of the study. Conclusions Overall, each RNS and tumor size strongly correlated with the WIT in patients who underwent RPN. However, the RNS outperformed tumor size in small (<3 cm) renal masses with an optimal discriminating power, whereas for relatively larger (>3 cm) tumors the WIT was significantly dependent on tumor size and every centimeter may count. Besides, the subcategories had different effects on the WIT. © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e654-e655 Advertisement Copyright & Permissions© 2014MetricsAuthor Information Linhui Wang More articles by this author Zhenjie Wu More articles by this author Huamao Ye More articles by this author Mingmin Li More articles by this author Yinghao Sun More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

631 RENAL TUMOR CONTACT SURFACE AREA: A NOVEL CT-PARAMETER FOR PREDICTING PERI-OPERATIVE OUTCOMES USING ADVANCED IMAGE-PROCESSING SOFTWARE

You have accessJournal of UrologyKidney Cancer: Evaluation & Staging (I)1 Apr 2013631 RENAL TUMOR CONTACT SURFACE AREA: A NOVEL CT-PARAMETER FOR PREDICTING PERI-OPERATIVE OUTCOMES USING ADVANCED IMAGE-PROCESSING SOFTWARE Scott Leslie, Andre Luis de Castro Abreu, Hamed Ahmadi, Andre K Berger, R James Yu, Sheaumei Tsai, Steve Dong, Raed A Azhar, Mehrdad Alemozaffar, Arnaud Marien, Sunao Shoji, Monish Aron, Inderbir S Gill, Vinay A Duddalwar, and Mihir M Desai Scott LeslieScott Leslie Los Angeles, CA More articles by this author , Andre Luis de Castro AbreuAndre Luis de Castro Abreu Los Angeles, CA More articles by this author , Hamed AhmadiHamed Ahmadi Los Angeles, CA More articles by this author , Andre K BergerAndre K Berger Los Angeles, CA More articles by this author , R James YuR James Yu Los Angeles, CA More articles by this author , Sheaumei TsaiSheaumei Tsai Los Angeles, CA More articles by this author , Steve DongSteve Dong Los Angeles, CA More articles by this author , Raed A AzharRaed A Azhar Los Angeles, CA More articles by this author , Mehrdad AlemozaffarMehrdad Alemozaffar Los Angeles, CA More articles by this author , Arnaud MarienArnaud Marien Los Angeles, CA More articles by this author , Sunao ShojiSunao Shoji Los Angeles, CA More articles by this author , Monish AronMonish Aron Los Angeles, CA More articles by this author , Inderbir S GillInderbir S Gill Los Angeles, CA More articles by this author , Vinay A DuddalwarVinay A Duddalwar Los Angeles, CA More articles by this author , and Mihir M DesaiMihir M Desai Los Angeles, CA More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2013.02.183AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The surface area of contact that a tumor has with the adjacent renal parenchyma considerably determines the extent of resection of kidney tissue during partial nephrectomy (PN), and thus may impact on peri-operative outcomes. We present a novel method of calculating renal tumor contact surface area (CSA) using image-processing technology and correlate it with peri-operative variables in patients undergoing PN. METHODS From January 2010 - August 2011, 162 patients underwent minimally invasive PN for tumor, and had CSA data available using image rendering software (3D Synapse - Fuji film&©). Pre-operative CT scans were evaluated using 3D synapse to calculate CSA for each tumor (figure). This was performed by first calculating the tumor volume and percentage of tumor located within the renal parenchyma. The total surface area (4πr2) of the tumor was then multiplied by the percent intra-parenchymal component to give the CSA for each tumor. CSA was then correlated with baseline demographics and peri-operative outcomes. RESULTS Mean tumor size was 3.1 cm and mean CSA was 18.3 cm2. Univariate analysis demonstrated that CSA significantly correlated with blood loss (p=0.0001), operative time (p=0.003), length of hospital stay (p=0.0028), and post-operative eGFR (0.0124). On multivariable logistic regression a CSA ≥ 20 cm2 was an independent predictor of overall complications and adverse perioperative outcomes. CONCLUSIONS In patients undergoing partial nephrectomy, tumors with greater contact surface area with surrounding renal parenchyma require a more extensive resection, thus impacting on peri-operative outcomes including blood loss, operative duration, complications and renal function. If these findings are validated in larger cohorts, future nephrometry systems could incorporate CSA measurements to objectively quantify renal tumor complexity and predict peri-operative outcomes of partial nephrectomy surgery. © 2013 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 189Issue 4SApril 2013Page: e258 Advertisement Copyright & Permissions© 2013 by American Urological Association Education and Research, Inc.MetricsAuthor Information Scott Leslie Los Angeles, CA More articles by this author Andre Luis de Castro Abreu Los Angeles, CA More articles by this author Hamed Ahmadi Los Angeles, CA More articles by this author Andre K Berger Los Angeles, CA More articles by this author R James Yu Los Angeles, CA More articles by this author Sheaumei Tsai Los Angeles, CA More articles by this author Steve Dong Los Angeles, CA More articles by this author Raed A Azhar Los Angeles, CA More articles by this author Mehrdad Alemozaffar Los Angeles, CA More articles by this author Arnaud Marien Los Angeles, CA More articles by this author Sunao Shoji Los Angeles, CA More articles by this author Monish Aron Los Angeles, CA More articles by this author Inderbir S Gill Los Angeles, CA More articles by this author Vinay A Duddalwar Los Angeles, CA More articles by this author Mihir M Desai Los Angeles, CA More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

1100 COMPARISON OF PERIOPERATIVE OUTCOMES OF TRANSPERITONEAL VERSUS RETROPERITONEAL ROBOT ASSISTED PARTIAL NEPHRECTOMY - A MATCHED PAIR ANALYSIS BY NEPHROMETRY

You have accessJournal of UrologyKidney Cancer: Localized I1 Apr 20121100 COMPARISON OF PERIOPERATIVE OUTCOMES OF TRANSPERITONEAL VERSUS RETROPERITONEAL ROBOT ASSISTED PARTIAL NEPHRECTOMY - A MATCHED PAIR ANALYSIS BY NEPHROMETRY Seo Yeon Lee, Jae Duck Choi, Sin-Woo Lee, Jung Hun Kang, Joong Seo Ahn, Hyung Joon Kim, Hyun Hwan Sung, Bum Soo Park, Byong Chang Jeong, Seong Soo Jeon, Hyun Moo Lee, Han Yong Choi, and Seong Il Seo Seo Yeon LeeSeo Yeon Lee Goyang, Gyeonggi, Korea, Republic of More articles by this author , Jae Duck ChoiJae Duck Choi Gyeongju, Korea, Republic of More articles by this author , Sin-Woo LeeSin-Woo Lee Seoul, Korea, Republic of More articles by this author , Jung Hun KangJung Hun Kang Seoul, Korea, Republic of More articles by this author , Joong Seo AhnJoong Seo Ahn Seoul, Korea, Republic of More articles by this author , Hyung Joon KimHyung Joon Kim Seoul, Korea, Republic of More articles by this author , Hyun Hwan SungHyun Hwan Sung Seoul, Korea, Republic of More articles by this author , Bum Soo ParkBum Soo Park Seoul, Korea, Republic of More articles by this author , Byong Chang JeongByong Chang Jeong Seoul, Korea, Republic of More articles by this author , Seong Soo JeonSeong Soo Jeon Seoul, Korea, Republic of More articles by this author , Hyun Moo LeeHyun Moo Lee Seoul, Korea, Republic of More articles by this author , Han Yong ChoiHan Yong Choi Seoul, Korea, Republic of More articles by this author , and Seong Il SeoSeong Il Seo Seoul, Korea, Republic of More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.1208AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES To compare transperitoneal and retroperitoneal robot assisted partial nephrectomy (RPN) with matched analysis using the three nephrometry systems, RENAL, PADUA and C-index. METHODS Ninety two patients underwent RPN from December 2008 to June 2011. Initial 20 cases and 4 cases performed with other operation or multiple renal masses were excluded. Nephrometry scores were calculated with the computed tomography. Transperitoneal and retroperitoneal approach groups were matched by the three nephrometry systems each other and the perioperative outcomes were compared. RESULTS Forty one transperitoneal RPN and 27 retroperitoneal RPN cases were matched by 1:1. There was no significant difference of age, sex, laterality, clinical stage between two groups when matched by each system. Matched by RENAL system, operative time and warm ischemic time (WIT) was shorter and estimated blood loss (EBL) was less in the retroperitoneal RPN group (p<0.05). Matched by PADUA, retroperitoneal RPN group showed shorter operative time, WIT and period to oral resumption (p<0.05). Matched by C-index, operative time, WIT, period to oral resumption was shorter and EBL was less in the retroperitoneal approach (p<0.05). There was no significant difference in the visual analogue pain scale score and complication between the two groups. CONCLUSIONS Matching with the three nephrometry systems, retroperitoneal RPN showed shorter operative time, WIT, period to oral resumption and lesser EBL compared to transperitoneal RPN showing no significant difference in the pain score and complication. Therefore retroperitoneal RPN is considered as a recommended modality for the surgeons who are experienced with retroperitoneal approach. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e446-e447 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Seo Yeon Lee Goyang, Gyeonggi, Korea, Republic of More articles by this author Jae Duck Choi Gyeongju, Korea, Republic of More articles by this author Sin-Woo Lee Seoul, Korea, Republic of More articles by this author Jung Hun Kang Seoul, Korea, Republic of More articles by this author Joong Seo Ahn Seoul, Korea, Republic of More articles by this author Hyung Joon Kim Seoul, Korea, Republic of More articles by this author Hyun Hwan Sung Seoul, Korea, Republic of More articles by this author Bum Soo Park Seoul, Korea, Republic of More articles by this author Byong Chang Jeong Seoul, Korea, Republic of More articles by this author Seong Soo Jeon Seoul, Korea, Republic of More articles by this author Hyun Moo Lee Seoul, Korea, Republic of More articles by this author Han Yong Choi Seoul, Korea, Republic of More articles by this author Seong Il Seo Seoul, Korea, Republic of More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...