|Year : 2020 | Volume
| Issue : 3 | Page : 121-127
Nephrometry scores in renal cancer
Nikolaos A Kostakopoulos, Titos Markopoulos, Andreas A Skolarikos
Department of Urology, University of Athens, Sismanogleio General Hospital Athens, Greece
|Date of Submission||23-Dec-2020|
|Date of Decision||11-Jan-2021|
|Date of Acceptance||18-Jan-2021|
|Date of Web Publication||22-Feb-2021|
Nikolaos A Kostakopoulos
Department of Urology, University of Athens, Sismanogleio General Hospital, Athens
Source of Support: None, Conflict of Interest: None
Several independent tools and measurements can be used to assess the same endpoint. This is the case for renal tumors, for which different nephrometry scores (NSs) based on preoperative imaging are currently available. These systems provide objective information with regard to surgical complexity, risk of blood loss, ischemia time, and perioperative complications that can assist physicians in the decision-making process and in planning the most appropriate surgical approach. In this review article, the most widely used preoperative NSs are being mentioned; their parameters are analyzed and their usefulness and reliability in everyday clinical and surgical practice are being compared.
Keywords: Arterial-based complexity, C-index, NePhRO, nephrometry scoring systems, partial nephrectomy, Preoperative Aspects and Dimensions Used for an Anatomical score, Radius, Exophytic/Endophytic, Nearness, Anterior/Posterior, and Location nephrometry score
|How to cite this article:|
Kostakopoulos NA, Markopoulos T, Skolarikos AA. Nephrometry scores in renal cancer. Hellenic Urology 2020;32:121-7
| Introduction|| |
The preoperative objective assessment of renal surgical anatomy is essential for treatment planning and for minimizing the perioperative complications of nephron-sparing surgery (NSS) and tumor ablation techniques.,
Several objective anatomic classification systems or nephrometry scores (NSs), such as the Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) classification system; the Radius, Exophytic/Endophytic, Nearness, Anterior/Posterior, and Location (RENAL) NS; the C-index; an arterial-based complexity (ABC) scoring system (SS); the Zonal NePhRO SS; and the Margin, Ischemia, and Complications (MIC) score, have been proposed to standardize the description of renal tumors.
These scores can assist surgeons in determining the tumor anatomical complexity and together with the patient's features and the surgeon's experience, in selecting the most optimal treatment option, and in counseling patients.
The aim of this study was to evaluate the literature for the available nephrometry SSs and to compare the effectiveness of the existing systems in predicting the postoperative complications and the outcome of NSS.,
| Materials and Methods|| |
A nonsystematic search was performed in the MEDLINE database of the National Library of Medicine, PubMed, Cochrane Library, and other libraries for comparative studies, clinical trials, and systematic reviews on the topic using the terms: “Nephrometry scores,” “R.E.N.A.L. nephrometry score,” “partial nephrectomy,” “P.A.D.U.A. score,” “C-index,” “Zonal NePhRO,” “arterial based complexity,” “nephron sparing surgery,” “Margin, Ischemia, and Complications score” in various combinations.
| Nephrometry Scores|| |
Radius, Exophytic/Endophytic, Nearness, Anterior/Posterior, and Location
Standardized reporting of renal tumor size, location, and depth is essential for decision-making and effective comparisons. The RENAL NS is a reproducible standardized classification system that quantitates the salient anatomy of renal masses.
The RENAL NS is based on five critical and reproducible anatomical features of solid renal masses. Of the five components, four are scored on a one-, two-, or three-point scale with the 5th indicating the anterior or posterior location of the mass relative to the coronal plane of the kidney.
The RENAL NS consists of (R) radius (tumor size as maximal diameter), (E) exophytic/endophytic properties of the tumor, (N) nearness of tumor deepest portion to the collecting system or sinus, (A) anterior (a)/posterior (p) descriptor, and the (L) location relative to the polar line. The suffix h (hilar) is assigned to tumors that abut the main renal artery or vein. It was firstly developed and applied to 50 consecutive masses resected at Fox Chase Cancer Center [Table 1].
An article in the Journal of Endourology in September 2016 suggests that RENAL score can be used to predict postoperative pathologically determined healthy renal volume loss or nonneoplastic parenchymal volume (NNPV) removed and the renal function decline in patients undergoing robotic partial nephrectomy (RPN).
The Multi-Institutional Mount Sinai Kidney Cancer Database was used to identify 1235 patients who underwent RPN between January 2008 and February 2016, of whom 366 had complete data, including NNPV removed. Mann–Whitney U-tests and univariable linear regression models were used to assess the relationships between RENAL NS, warm ischemia time (WIT), and NNPV removed. Univariable and multivariable regression models were then used to assess the independent relationships of each of these variables with percent change in estimated glomerular filtration rates (eGFRs) and acute kidney injury (AKI) within the first 30 postoperative days in addition to percent change in eGFR and progression to chronic kidney disease at a median follow-up of 6.9 months.
Increasing RENAL NS was shown to be a predictor of WIT (β = 0.92, P < 0.001) and of NNPV removed (β = 6.21, P < 0.001) in univariable analyses. In multivariable analysis, postoperative reduction in eGFR within the first 30 days of surgery was associated with both RENAL NS (β = −2.02, P < 0.001) and NNPV removed (β = −5.19, P = 0.015). RENAL NS (odds ratio [OR] = 1.21, P = 0.013) and NNPV removed (OR = 1.90, P = 0.013) were also associated with an increased likelihood of AKI within the first 30 days. No significant association in this cohort was found between RENAL NS, NNPV removed, or WIT and renal function decline at 6.9 months.
The preoperative RENAL NS can be used to predict postoperative pathologically determined healthy renal volume loss or NNPV removed. Removal of not just the tumor but also the healthy surrounding parenchyma is important in determining renal function decline. As our understanding of the importance of renal volume loss grows, NNPV removed gains increasing utility as an easily determinable postoperative variable.
A study published in Urology in August 2015 showed that RN is independently associated with decreased renal function compared to partial nephrectomy (PN) for T2RM with RENAL sum ≤10, but not >10, with larger relative decrease in eGFR for each decrease in RENAL sum.
The role of the RENAL NS in predicting surgical outcomes in a series of robot-assisted partial nephrectomy (RAPN) was studied by Png et al. in the Journal of Urology in March 2013.
Of 99 cases of minimally invasive PN performed by a single surgeon from 2003 to 2011, 83 were performed with robotic assistance. A trained physician investigator applied the NS to these 83 cases using the preoperative computed tomography (CT) scans. Forty-two of these were reviewed by a urology resident to eliminate interobserver variation. Tumors were categorized into noncomplex (NS 4–6) or complex (NS 7–12) tumors, and perioperative outcomes were compared. Outcomes were also compared by each component of the NS. Perioperative outcomes were analyzed using Chi-square tests and Mann–Whitney/Kruskal–Wallis tests. Univariate regression was used to analyze trends between nephrometry and outcomes.
Strong correlation was found between the two sets of NS (Spearman correlational coefficient 0.814, P < 0.001). Comparing between noncomplex and complex tumors, statistical differences were found in operative time (181 min vs. 215 min, P = 0.028) and ischemia time (21 min vs. 24 min, P = 0.006). Complication rates, blood loss, conversion rate, and decrease in glomerular filtration rate were similar in both groups. On univariate regression analysis, only WIT showed a significant trend with the overall NS (P = 0.007) and the location score (P = 0.031).
A high NS was not associated with clinically worse outcomes during RAPN. Such renal tumors can still be excised safely with robotic assistance without adverse long-term effects.
Preoperative Aspects and Dimensions Used for an Anatomical score
The PADUA score is a simple anatomical system that can be used to predict the risk of surgical and medical perioperative complications in patients undergoing open NSS. The use of an appropriate score can help clinicians stratify patients suitable for NSS into subgroups with different complication risks and can help researchers evaluate the real comparability among patients undergoing NSS with different surgical approaches.
In a prospective study published in European Urology in 2009, 164 consecutive patients who underwent NSS for renal tumors at a tertiary academic referral center from January 2007 to December 2008 were enrolled prospectively. The purpose of the study was to propose an original, standardized classification of renal tumors suitable for NSS based on their anatomical features and size and to evaluate the ability of this classification to predict the risk of overall complications resulting from the surgery.
All patients underwent open PN without vessel clamping. All tumors were classified by integrating size with the following anatomical features: anterior or posterior face, longitudinal, and rim tumor location; tumor relationships with renal sinus or urinary collecting system; and percentage of tumor deepening into the kidney. The authors generated an algorithm evaluating each anatomical parameter and tumor size (the PADUA score) to predict the risk of complications. Anatomical features included are (a) longitudinal classification, (b) margin location of tumors, (c) tumor relationship with renal sinus, (d) tumor relationship with urinary collecting system, (e) tumor deepening into the parenchyma, and (f) tumor size [Table 2].
|Table 2: Preoperative Aspects and Dimensions Used for an Anatomical nephrometry score|
Click here to view
Overall rates of complication were significantly correlated to all the evaluated anatomical aspects, excluding clinical size and anterior or posterior location of the tumor. By multivariate analysis, PADUA scores were independent predictors of the occurrence of any grade complications (hazard ratio [HR] for score 8–9 vs. 6–7: 14.535; HR for score ≥10 vs. 6–7: 30.641). Potential limitations were the limited number of patients with T1b tumors included in the study and the lack of laparoscopically treated patients.
In May 2014, Shin et al. evaluated whether assessing the anatomical characteristics of renal masses increases the accuracy of prediction of tumor pathology in small renal masses (SRMs).
The authors retrospectively reviewed 1129 consecutive patients who underwent extirpative surgeries for a clinical T1 renal mass, for which the PADUA classification were available.
They concluded that age, sex, and tumor size are the primary predictors of tumor pathology of SRMs, and incorporating other anatomical characteristics has only a limited positive effect on the accuracy of prediction of pathological outcomes.
A novel classification system was introduced by Ficarra et al. in 2019 to simplify the original PADUA classification of renal tumors. The Simplified PADUA REnal NS system including (i) rim location, (ii) renal sinus involvement, (iii) exophytic rate, and (iv) tumor dimension showed equal performance in comparison with the original PADUA score (area under the curve [AUC] 0.657 vs. 0.664) and similar accuracy in predicting overall complications. However, the addition of tumor contact surface area was not associated with an increase in prognostic accuracy.
Tumor location assessment is essential to plan nephron-sparing kidney surgery. Centrality index (C-index) scoring provides a clinically useful measure of tumor centrality. This system may allow improved clinical and radiological assessment of kidney tumors and improved reporti7ng of quantitative tumor site.
A C-index of 0 equates to a tumor that is concentric with the center of the kidney. A C-index of 1 equates to a tumor with its periphery touching the kidney center. As the C-index increases, the tumor periphery becomes more distant from the kidney center.
C-index scoring was introduced by Simmons et al. in the Journal of Urology in 2010, as a method to quantify the proximity of kidney tumors to the renal central sinus for reporting and surgical management. C-index scoring was done using standard two-dimensional cross-sectional computerized tomography images in 133 consecutive patients undergoing transperitoneal laparoscopic PN between September 2003 and November 2005. The Pythagorean theorem was used to calculate the distance from tumor center to kidney center. The distance was divided by tumor radius to obtain the C-index. The correlation of the C-index with laparoscopic PN operative parameters and the urological complication rate was assessed. C-index accuracy and interobserver variability were also assessed. Multivariate regression analysis revealed an association of the C-index with WIT (P = 0.004), which is a surrogate for technical complexity. Interobserver correlation of C-index values was >93% with an estimated learning curve of 14 cases required for measurement variability to decrease below 10% of the mean C-index of 10 consecutive cases.
The ABC SS is a novel anatomy-reproducible tool developed to help patients and doctors understand the complexity of renal masses and predict the outcomes of kidney surgery. Introduced in European Urology in the January 2016 issue, its purpose is to predict morbidity of PN. In the study, four readers independently scored contrast-enhanced CT images of 179 patients who underwent PN.
Renal cortical masses were categorized by the order of vessels needed to be transected/dissected during PN. Scores of 1, 2, 3S, or 3H were assigned to tumors requiring transection of interlobular and arcuate arteries, interlobar arteries, segmental arteries, or in close proximity of the renal hilum, respectively, during PN.
Interobserver variability was assessed with kappa values and percentage of exact matches between each pairwise combination of readers. Linear regression was used to evaluate the association between reference scores and ischemia time, estimated blood loss, and eGFRs at 6 weeks and 6 months after surgery adjusted for baseline eGFR. Fisher's exact test was used to test for differences in risk of urinary fistula formation by reference category assignment.
Pairwise comparisons of readers' score assignments were significantly correlated (all P < 0.0001), average kappa = 0.545 across all reader pairs. The average proportion of exact matches was 69%. Linear regression between the complexity score system and surgical outcomes showed significant associations between reference category assignments and ischemia time (P < 0.0001) and estimated blood loss (P = 0.049). Fisher's exact test showed a significant difference in risk of urinary fistula formation with higher reference category assignments (P = 0.028). Limitations include use of a single institutional cohort to evaluate this SS.
In conclusion, the ABC SS for PN is intuitive, easy to use, and demonstrated good correlation with perioperative morbidity.
The Zonal NePhRO SS takes into account four parameters of SRMs that collectively indicate whether a patient's tumor should be removed. These are the extent of the tumor (“Ne” – nearness to cortex, medulla, and collecting system), whether it includes the collecting system (“Ph” – physical zones), the tumor's radius (“R”), and whether the mass is largely exophytic or endophytic (“O” – organization). Each patient is assigned a score of 1, 2, or 3 for each parameter, with low risk for malignancy being scores of 4–6 points, intermediate risk being scores of 7–9 points, and high risk being scores of 10–12.
Margin, Ischemia, and Complications score
Complete removal of the primary tumor remains the most relevant outcome of the surgical therapies for renal cell carcinoma (RCC). Evaluating the surgical margins of the specimen after PN is the best way to determine whether the primary tumor was completely removed. Usually, positive surgical margin (PSM) is defined as cancer cells at the level of the inked parenchymal excision surface.
More controversial is the method and timing of evaluating postprocedure renal function. The most important surgical variable that influences renal function is ischemia time. The most common method used to induce ischemia is clamping the renal artery with or without the renal vein for a period of time (i.e., WIT). Having a WIT <20 min can be considered a good clinical cutoff value.
Last, the safety profile of PN has been recently evaluated using the modified Clavien–Dindo classification, which has allowed clinicians to identify major postoperative complications by treatment.
Taking these three variables into consideration, Buffi N et al. proposed to combine them in a new MIC binary system with the aim of identifying patients with the best outcomes after PN procedures. According to the new system, the goal of PN is reached when (1) surgical margins are negative, (2) WIT is <20 min, and (3) no major complications (Grade 3–4 according to Clavien classification) are observed.
The application of this system could generate some issues. First, some authors use zero-ischemia or nonclamping techniques. In this case, the second goal of the system will be reached by definition. Second, the MIC rate could be influenced by the different anatomic and topographic characteristics of the treated tumor. More complex tumors should have a lower MIC rate than less complex ones. For this reason, the authors suggest stratifying the MIC rates according to the PADUA or RENAL nephrometry risk-group categories.
In a preliminary analysis, 99 consecutive patients who underwent RAPN for cT1a/cT1b renal tumors were evaluated at a tertiary care high-volume center between March 2008 and January 2012. In this population, the overall number (percentage) of PSMs, patients with <20 min of ischemia time, and complications were 7 (7%), 16 (16.6%), and 10 (10%), respectively. MIC rate was 75.8%. This proportion gradually increased with surgical experience from 66.7% to 87.9% in the last tertile of patients. The mean pre- and postoperative GFRs were 95.04 ml/min (range: 34.9–185.4 ml/min) and 99.03 ml/min (range: 45.1–197.7 ml/min), respectively (P = 0.2).
The preliminary findings showed that, besides surgeon experience, tumor size and location appear to have an important impact on MIC, as increasing tumor dimension is significantly related to a decrease in MIC achievement. In light of this, using the PADUA score might allow an adequate postoperative assessment of outcomes.
In conclusion, the MIC system could be easily adopted to standardize evaluation of PN outcomes in patients with renal tumors. This system could further improve the comparison of results from different series and of different surgical approaches. Prospective evaluation in larger series may define more exactly the potential role of the MIC score after PN.
| Discussion|| |
NSs are designed for standardized reporting of renal tumors and predicting complications. Multiple scores are available, but there is a lack of systematic comparison. In a study published in Clinical Genitourinary Cancer in August 2016, the most frequently used nephrometry tests were compared. A total of 305 consecutive patients admitted for open PN to 2 urological hospitals were prospectively assessed. Five cases with conversion to radical nephrectomy were excluded from further analysis. RENAL, PADUA, C-index, and NePhRO scores were obtained from preoperative sectional imaging. In addition, interobserver variance between 2 urologists and a radiologist was analyzed for 50 patients. Linear and ordered logistic regression was used to evaluate the association between scores and surgical parameters. Receiver operating characteristic analysis was employed to assess the predictive value for requirement of ischemia and opening of the collecting system.
High interobserver agreement was observed for RENAL (0.92 and 0.80), PADUA (0.81 and 0.85), NePhRO (0.94 and 0.82), and the C-index (0.98 and 0.95). All scores showed a significant association with opening of the collecting system (P < 0.016), requirement of on-clamp excision (P < 0.001), and ischemia time (P < 0.001). Logistic regression identified RENAL, PADUA, and NePhRO scores to be an independent predictor for severe complications (P = 0.016, P = 0.011, and P = 0.005, respectively). No correlation was found for the C-index (ß = 0.98; P = 0.779). Predictive effectiveness for opening of the collecting system and for on-clamp excision showed comparable AUC values for the 4 scores.
All SSs represent objective and reproducible measurement tools for renal tumor complexity that correlate well with surgical outcome. RENAL, PADUA, and NePhRO scores are comparable and seem to be superior to the more complex C-index system.
In a review article published in the Journal of Endourology in December of 2011, the C-index, PADUA classification, and RENAL nephrometry schemes were developed as standardized SSs to quantify anatomic characteristics of kidney tumors. The objective of the study was to establish reliability and assess relationships between these three SSs and perioperative and postoperative variables.
A retrospective chart review was performed in 101 patients who underwent laparoscopic PN. The nephrometry schemes were correlated with intraoperative and postoperative parameters using Spearman correlations. In addition, interobserver reliability was assessed on 50 of the patients by interclass correlations comparing the scores assigned by two residents and one fellow who reviewed preoperative CT studies of these patients.
The interobserver correlation was 0.84 for the C-index, 0.81 for the PADUA, and 0.92 for the RENAL SSs, demonstrating excellent interobserver reliability. All three SSs were significantly associated with WIT (C-index, P = −0.44; PADUA, P = 0.25; and RENAL, P = 0.32) and percent change in creatinine level (C-index, P = −0.33; PADUA, P = 0.37; and RENAL, P = 0.37). There were no significant associations between any of the three SSs assessed and the occurrence of complications, operative time, or estimated blood loss. No significant correlation was found between the PADUA and RENAL SS and length of stay; however, C-index did show a significant relationship for patients with lower scores having longer hospital stays (P = −0.21).
All three SSs demonstrated reliability among observers and represent novel methods of quantitatively describing renal tumors. They were all associated with WIT, percent change in creatinine level, and tumor size. They did not, however, correlate with any other perioperative parameters investigated. At this time, these SSs provide a common language for describing renal tumors.
A retrospective study of the Vattikuti Global Quality Initiative in Robotic Urologic Surgery (GQI-RUS) database that was published in BJU International in August 2016 had as its purpose to evaluate and compare the correlations between PADUA and RENAL (Radius [tumor size as maximal diameter], Exophytic/endophytic properties of the tumor, Nearness of tumor deepest portion to the collecting system or sinus, Anterior [a]/posterior [p] descriptor, and the Location relative to the polar line) NSs and perioperative outcomes and postoperative complications in a multicenter, international series of patients undergoing RAPN for masses suspicious for RCC.
The clinical records of patients who underwent RAPN between 2010 and 2013 for clinical N0M0 renal tumors in four international centers that completed all the data required for the Vattikuti GQI-RUS database were retrospectively evaluated. All patients underwent preoperative CT or magnetic resonance imaging to define the clinical stage and anatomical characteristics of the tumors. PADUA and RENAL scores were retrospectively assessed in each center. Univariate and multivariate analyses were used to evaluate the correlations between age, gender, Charlson Comorbidity Index, clinical tumor size, PADUA and RENAL complexity group categories and WIT of >20 min, urinary calyceal system closure, and grade of postoperative complications.
Overall, 277 patients were evaluated. The median (interquartile range) tumor size was 33.0 (22.0–43.0) mm. The median PADUA and RENAL scores were eight and seven, respectively; 112 (40.4%), 86 (31.0%), and 79 (28.5%) patients were classified in the low-, intermediate-, or high-complexity group according to PADUA score, while 118 (42.5%), 139 (50.1%), and 20 (7.2%) were classified in the low-, intermediate-, or high-complexity group according to RENAL score, respectively. Both nephrometry tools significantly correlated with perioperative outcomes at univariate and multivariate analyses.
A precise stratification of patients before PN is recommended to consider both the potential threats and benefits of NSS. In this analysis, both PADUA and RENAL were significantly associated with predicting prolonged WIT and high-grade postoperative complications after RAPN.
Another study published in International Journal of Urology in November 2015 compares diameter-axial-polar NS and RENAL NS for surgical outcomes following laparoscopic PN.
Data from 134 patients who underwent laparoscopic PN were retrospectively reviewed, using diameter-axial-polar and RENAL scores. Data for WIT and estimated blood loss intraoperatively and percentage change in eGFR 6 months and 1 year postoperatively were analyzed. Both scores were classified as low, middle, and high risk and were used to compare the three analyzed parameters.
The median tumor size was 2.3 cm (range: 1.0–5.4 cm); WIT was 25.4 min (range: 6.5–57 min), and at 6 months and 1 year, percentage change in eGFR was 93% (range: 51.7%–133.3%) and 91% (range: 49.4%–137.6%), respectively. There were no significant differences in WIT and estimated blood loss for RENAL between risk groups (P = 0.38 and 0.09, respectively) but significant differences between groups for diameter-axial-polar score (P = 0.02 and 0.01, respectively). There were no significant differences in either score between groups for percentage change in eGFR at 6 months and 1 year. A total of 27 high-risk cases with a diameter-axial-polar score of seven points underwent laparoscopic PN safely; all three cases with a diameter-axial-polar score of eight points were converted to open PN.
Diameter-axial-polar score seems to estimate the complexity of tumor characteristics in patients undergoing laparoscopic PN better than RENAL score. It has a better correlation with WIT and estimated blood loss.
A systematic review and meta-analysis by Veccia et al. in May 2020 about the predictive value of NSs in NSS showed that the RENAL and PADUA scores, which are the most widely assessed in the literature, are easy to calculate and have a good correlation with most outcomes, such as WIT and overall complications. Furthermore, RENAL score and peritumoral artery SS were independent predictors of an eGFR increase.
| Conclusion|| |
NSs, which are SSs based on radiological imaging and made to grade the complexity of a renal tumor, are essential for treatment planning and for minimizing the perioperative complications of NSS and tumor ablation techniques. In this study, we present the most widely assessed nephrometry SSs and compare their effectiveness in predicting the outcomes of patients undergoing surgical removal of renal tumors.,,
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Klatte T, Ficarra V, Gratzke C, Kaouk J, Kutikov A, Macchi V, et al
. A Literature Review of Renal Surgical Anatomy and Surgical Strategies for Partial Nephrectomy. Eur Urol 2015;68:980-92.
Ljungberg B, Albiges L, Abu-Ghanem Y, Bensalah K, Dabestani S, Fernández-Pello S, et al
. European Association of Urology Guidelines on Renal Cell Carcinoma: The 2019 Update. Eur Urol 2019;75:799-810.
Kutikov A, Uzzo RG. The R.E.N.A.L. nephrometry score: A comprehensive standardized system for quantitating renal tumor size, location and depth. J Urol 2009;182:844-53.
Husain FZ, Rosen DC, Paulucci DJ, Sfakianos JP, Abaza R, Badani KK. R.E.N.A.L. Nephrometry score predicts non-neoplastic parenchymal volume removed during robotic partial nephrectomy. J Endourol 2016;30:1099-1104. doi 10.1089/end.2016.0337.PMID:27604690.
Kopp RP, Liss MA, Mehrazin R, Wang S, Lee HJ, Jabaji R, et al
. Analysis of≥7 cm using the RENAL Score. Urology 2015;86:312-9.
Png KS, Bahler CD, Milgrom DP, Lucas SM, Sundaram CP. The role of R.E.N.A.L. nephrometry score in the era of robot-assisted partial nephrectomy. J Endourol 2013;27:304-8.
Ficarra V, Novara G, Secco S, Macchi V, Porzionato A, De Caro R, et al
. Preoperative aspects and dimensions used for an anatomical (PADUA) classification of renal tumours in patients who are candidates for nephron-sparing surgery. Eur Urol 2009;56:786-93.
Shin TY, Kim J, Koo KC, Lim SK, Kim DW, Kang MW, et al
. Assessing the anatomical characteristics of renal masses has a limited effect on the prediction of pathological outcomes in solid, enhancing, small renal masses: Results using the PADUA classification system. BJU Int 2014;113:754-61.
Ficarr V, Porpiglia F, Crestani A, Minervini A, Antonellin A, Longo N, et al
. The Simplified PADUA REnal (SPARE) nephrometry system: a novel classification of parenchymal renal tumours suitable for partial nephrectomy. BJU Int 2019;124:621-8.
Simmons MN, Ching CB, Samplaski MK, Park CH, Gill IS. Kidney tumor location measurement using the C index method. J Urol 2010;183:1708-13.
Spaliviero M, Poon BY, Karlo CA, Guglielmetti GB, Di Paolo PL, Beluco Corradi R, et al
. An Arterial Based Complexity (ABC) Scoring System to assess the morbidity profile of partial nephrectomy. Eur Urol 2016;69:72-9.
Hakky TS, Baumgarten AS, Allen B, Lin HY, Ercole CE, Sexton WJ, et al
. Zonal NePhRO scoring system: A superior renal tumor complexity classification model. Clin Genitourin Cancer 2014;12:e13-8.
Buffi N, Lista G, Larcher A, Lughezzani G, Ficarra V, Cestari A, et al
. Margin, ischemia, and complications (MIC) score in partial nephrectomy: A new system for evaluating achievement of optimal outcomes in nephron-sparing surgery. Eur Urol 2012;62:617-8.
Kriegmair MC, Mandel P, Moses A, Lenk J, Rothamel M, Budjan J, et al
. Defining renal masses: Comprehensive comparison of RENAL, PADUA, NePhRO, and C-index score. Clin Genitourin Cancer 2017;15:248-550.
Okhunov Z, Rais-Bahrami S, George AK, Waingankar N, Duty B, Montag S, et al
. The comparison of three renal tumor scoring systems: C-Index, P.A.D.U.A., and R.E.N.A.L. nephrometry scores. J Endourol 2011;25:1921-4.
Schiavina R, Novara G, Borghesi M, Ficarra V, Ahlawat R, Moon DA, et al
. PADUA and R.E.N.A.L. nephrometry scores correlate with perioperative outcomes of robot-assisted partial nephrectomy: Analysis of the Vattikuti Global Quality Initiative in Robotic Urologic Surgery (GQI-RUS) database. BJU Int 2017;119:456-63.
Yoshida K, Kinoshita H, Yoshida T, Takayasu K, Mishima T, Yanishi M, et al
. Comparison of diameter-axial-polar nephrometry score and RENAL nephrometry score for surgical outcomes following laparoscopic partial nephrectomy. Int J Urol 2016;23:148-52.
Veccia A, Antonelli A, Uzzo RG, Novara G, Kutikov A, Ficarra V, et al
. Predictive value of nephrometry scores in nephron-sparing surgery: A systematic review and meta-analysis. Eur Urol Focus 2020;6:490-504.
[Table 1], [Table 2]