Association of Tumor Size, Location, R.E.N.A.L., PADUA and Centrality Index Score with Perioperative Outcomes and Postoperative Renal Function

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

INTRODUCTION

Due to their increasing prevalence and complex management, renal tumors are challenging for health professionals. The study aims to evaluate the usefulness of R.E.N.A.L. and PADUA nephrometry scores in the prediction of complications after percutaneous cryoablation.

MATERIAL AND METHODS

The study prospectively analyzed 90 patients with 101 stage T1a renal cell carcinoma (RCC) tumors treated with cryoablation.

RESULTS

Ninety patients with 101 small renal tumors who received cryoablative therapy were investigated. The mean age of the patients was 68 years and 74.4% were male. Most tumors were smaller than 4 cm (89.1%) and the mean PADUA and R.E.N.A.L. scores were 8.65 and 7.35, respectively. Complications were observed in 12 cases. PADUA and R.E.N.A.L. scores demonstrated moderate predictive power (AUC = 0.58 and AUC = 0.63, respectively) for post-cryoablation complications.

CONCLUSIONS

Percutaneous cryoablation is a safe and effective treatment for small renal tumors. The R.E.N.A.L. and PADUA renal nephrometry scores have moderate predictive power for complications associated with percutaneous cryoablation of renal tumors.

Impact of tumor contact surface area on collecting system entry in robot-assisted partial nephrectomy: a retrospective analysis

BACKGROUND

Collecting system entry in robot-assisted partial nephrectomy may occur even in cases showing a low N factor in the R.E.N.A.L nephrometry score. Therefore, in this study, we focused on the tumor contact surface area with the adjacent renal parenchyma and attempted to construct a novel predictive model for collecting system entry.

METHODS

Among 190 patients who underwent robot-assisted partial nephrectomy at our institution from 2015 to 2021, 94 patients with a low N factor (1-2) were analyzed. Contact surface was measured with three-dimensional imaging software and defined as the C factor, classified as C1, < 10 cm [2]; C2, ≥ 10 and < 15 cm [2]; and C3: ≥ 15 cm [2]. Additionally, a modified R factor (mR) was classified as mR1, < 20 mm; mR2, ≥ 20 and < 40 mm; and mR3, ≥ 40 mm. We discussed the factors influencing collecting system entry, including the C factor, and created a novel collecting system entry predictive model.

RESULTS

Collecting system entry was observed in 32 patients with a low N factor (34%). The C factor was the only independent predictive factor for collecting system entry in multivariate regression analysis (odds ratio: 4.195, 95% CI: 2.160-8.146, p < 0.0001). Models including the C factor showed better discriminative power than the models without the C factor.

CONCLUSIONS

The new predictive model, including the C factor in N1-2 cases, may be beneficial, considering its indication for preoperative ureteral catheter placement in patients undergoing robot-assisted partial nephrectomy.

Robotic versus Laparoscopic Partial Nephrectomy in the New Era: Systematic Review

(1) Background: In recent years there have been advances in imaging techniques, in addition to progress in the surgery of renal tumors directed towards minimally invasive techniques. Thus, nephron-sparing surgery has become the gold standard for the treatment of T1 renal masses. The aim of this study is to investigate the benefits of robotic partial nephrectomy in comparison with laparoscopic nephrectomy. (2) Methods: We performed a systematic review according to the PRISMA criteria during September 2022. We included clinical trials, and cohort and case-control studies published between 2000 and 2022. This comprised studies performed in adult patients with T1 renal cancer and studies comparing robotic with open and laparoscopic partial nephrectomy. A risk of bias assessment was performed according to the Newcastle—Ottawa scale. (3) Results: We observed lower hot ischemia times in the robotic surgery groups, although at the cost of an increase in total operative time, without appreciating the differences in terms of serious surgical complications (Clavien III–V). (4) Conclusions: Robotic partial nephrectomy is a safe procedure, with a shorter learning curve than laparoscopic surgery and with all the benefits of minimally invasive surgery.

Imaging Features of Renal Masses to Select Optimal Candidates for Tumor Enucleation Partial Nephrectomy

PURPOSE OF REVIEW

The goal of this paper was to critically evaluate preoperative findings that optimally select candidates for renal tumor enucleation partial nephrectomy.

RECENT FINDINGS

Tumor enucleation has been widely accepted as a management option for patients with chronic kidney disease, hereditary renal cell carcinoma, or multifocal disease. Recent evidence suggests safety and efficacy in the management of routine small renal masses. With recent advances in imaging, the literature for ruling out aggressive renal cell carcinoma and selection for tumor enucleation is robust. As the incidence of renal cell carcinoma rises, partial nephrectomy continues to be the mainstay of treatment for localized renal cell carcinoma. Tumor enucleation maximizes preservation of renal parenchyma without hindering oncologic outcomes. It is important to recognize key tumor radiologic findings which urologists may use to optimize patient selection for tumor enucleation.

A “3S+f” Nephrometry Score System to Predict the Clinical Outcomes of Laparoscopic Nephron-Sparing Surgery

Background

When we treat renal cell carcinoma by laparoscopic nephron-sparing surgery (NSS), it is essential to use an evaluation system to predict clinical outcomes. Hitherto, there are more than a dozen nephrometry score systems. In this study, through assessing the correlations between nephrometry score systems and clinical outcomes, we aim to provide a novel nephrometry score system—the “3S+f” score system—to simplify the evaluation of technical complexity of partial nephrectomy.

Methods

We retrospectively collected the data of 131 patients who underwent NSS, which was performed by a single surgeon (SZ) from January 2013 to July 2018 at Peking University Third Hospital. The “3S+f” score system contains four parameters: “size, side, site, and fat”, all of which can be obtained from preoperative imaging data. We evaluated the correlations between the “3S+f” score and clinical outcomes, and compared R.E.N.A.L. score and PADUA score.

Results

All the three nephrometry score systems were related to some clinical outcomes in univariate analyses. In multivariate regression models, the “3S+f” score, the R.E.N.A.L. score, and the PADUA score were significantly associated with operative time (p = 0.016, p = 0.035, and p = 0.001, respectively) and warm ischemia time (all p = 0.008, p < 0.001, and p < 0.001, respectively). “3S+f” was also significantly related to extubation time > 5 days (p = 0.018). In predicting operative time > 120 min and extubation time >5 days from ROC curves, the AUCs of the “3S+f” score (0.717 and 0.652, respectively) were larger than both the R.E.N.A.L (0.598 and 0.554, respectively) and PADUA (0.600 and 0.542, respectively) score systems.

Conclusion

A novel nephrometry score system—the “3S+f” score system—shows equivalent correlation and the ability in predicting clinical outcomes when compared to the R.E.N.A.L. score system and the PADUA score system, which can describe renal tumors.

Nephrometry scoring systems: their importance for the planning of nephron-sparing surgery and the relationships among them

In recent years, the development of new imaging techniques and scoring systems have improved the diagnosis and management of small renal masses. Imaging-based nephrometry scoring systems play an interesting role in the planning of nephron-sparing surgery, providing surgeons with the information necessary to determine the complexity of the renal mass, to deliver the appropriate postoperative care, and to predict adverse outcomes. The aim of this study was to review nephrometry scoring systems, evaluating their characteristics and the relationships among them. The urology and radiology communities should decide which nephrometry scoring system will prevail and be used in daily practice.

A pilot study investigating the feasibility of using a fully automatic software to assess the RENAL and PADUA score

PURPOSE

Image-based morphometric scoring systems such as the RENAL and PADUA scores are useful to evaluate the complexity of partial nephrectomy for renal cell carcinoma (RCC). The main aim of this study was to develop a new imaging software to enable an automatic detection and a 3D visualization of RCC from CT angiography (CTA) and to address the feasibility to use it to evaluate the features of the RENAL and the PADUA scores.

METHODS

A training dataset of 210 patients CTA-scans manually segmented was used to train a deep learning algorithm to develop the automatic detection and 3D-visualization of RCC. A trained operator blindly assessed the RENAL and PADUA scores on a testing dataset of 41 CTA from patients with RCC using a commercialized semi-automatic software (ground truth) and the new automatic software. Concordance between the two methods was evaluated.

RESULTS

The median PADUA score was 9 (7-11) and the renal score was 8 (5.5-9). The automatic software enabled to automatically detect the tumoral kidney and provided a 3D-visualization in all cases, with a computational time less than 20 seconds. Concordances for staging the anatomical features of the RENAL scores were respectively: 87.8% for radius, 85.4% for exophytic rate, 82.9% for location to the polar lines and 92.7% for the antero-posterior location. For the PADUA scores, concordances were 90.2% for tumor size, 85.4% for exophytic rate, 87.8% for polar location and 100% for renal rim.

CONCLUSION

By enabling an automatic 3D-visualization of tumoral kidney, this software could help to calculate morphometric scores, save time and improve reproducibility for clinicians.

LEVEL OF EVIDENCE: 4

Parallel comparison of R.E.N.A.L., PADUA, and C-index scoring systems in predicting outcomes after partial nephrectomy: A systematic review and meta-analysis

Objective

To parallelly compare the applicability of the radius, exophytic/endophytic, nearness, anterior/posterior, location nephrometry score (R.E.N.A.L.), the Preoperative Aspects and Dimensions Used for an Anatomical (PADUA), and the centrality index (C‐index) scoring systems in predicting clinical outcomes after partial nephrectomy (PN).

Methods

We searched EMBASE, PubMed, Ovid, and Web of Science to perform a meta‐analysis examining the correlation coefficients between three nephrometry scores (NSs) and warm ischemia time (WIT), estimated blood loss (EBL), operation time (OT), length of stay (LOS), and absolute change in eGFR (ACE) up to 25 January 2021.

Results

In total, 13 studies including 1496 patients met the criteria for further analysis. Overall, all scoring systems had statistically significant correlations with the WIT, EBL, OT, ACE and LOS and ACE, except for the correlation between PADUA and LOS (r = 0.16 [−0.00, 0.31], p > 0.05). The C‐index had the strongest correlation with WIT (r = −0.35 [−0.43, −0.26], p < 0.05) and ACE (r = −0.29 [−0.48, −0.10], p < 0.05). Weak correlations were observed between OT as well as EBL and each scoring system. Publication bias was observed in PADUA score predicting ACE (p = 0.04) and high heterogeneity was found in some of our results.

Conclusion

Until now, this is the first meta‐analysis that parallelly compares these three scoring systems in predicting outcomes after PN. We found that all NSs showed a statistically significant correlation with WIT, EBL, OT, and ACE. Moreover, the C‐index scoring system is the best predictor of WIT and ACE. Due to the existence of publication bias and high heterogeneity, more well‐designed and large‐scale studies are warranted for validation.

To our knowledge, this is the first meta‐analysis that parallelly compares these three scoring systems in predicting outcomes after PN. Overall, three scoring systems were significantly correlated with WIT, EBL, OT and ACE. Moreover, the C‐index scoring system outperformed R.E.N.A.L. and PADUA scoring systems in WIT and ACE.

Varying Outcomes among Patients with Large Angiomyolipomas according to the Treatment Method

PURPOSE

This study aimed to evaluate the outcomes of large angiomyolipoma (AML) treatment by selective arterial embolization (SAE) versus nephron-sparing surgery (NSS) using a robotic surgical system.

MATERIALS AND METHODS

Between January 2011 and June 2018, we retrospectively reviewed 25 patients who underwent robot-assisted partial nephrectomy (RAPN) or SAE for large AMLs. Ten patients underwent RAPN, and 15 underwent SAE. Patient demographics, AML characteristics, and operative and postoperative clinical outcomes were recorded and analyzed. Outcomes were compared between patients who underwent RAPN and patients who underwent SAE. Specifically, changes in renal function and size were evaluated after the treatment.

RESULTS

The mean age of the patients was 52.9 years, and 22 of 25 patients were female. The mean maximum AML diameter on computed tomography was 8.9 cm, and 8 patients had multiple masses. Twenty-two of 25 patients had moderate to high RENAL complexity. Patients who underwent SAE had more symptoms (p = 0.018) and higher RENAL complexity scores (p = 0.013) on average. On average, tumor size decreased by 99% among RAPN patients and by 58% among SAE patients (p = 0.001). Although the mean pretreatment estimated glomerular filtration rate (eGFR) was higher among RAPN patients (99.8 vs. 80.0 mL/min/1.73 m2, p = 0.043), there were no significant changes in eGFR in either group after the treatment. One patient in the RAPN group experienced complications, but the postoperative ileus resolved without intervention.

CONCLUSIONS

Both RAPN and SAE were effective and feasible treatment options for large AMLs. The AML characteristics and the condition of the patient might be important in determining the appropriate treatment method.

Nephrometry scores: a validation of three systems for peri-operative outcomes in retroperitoneal robot-assisted partial nephrectomy

OBJECTIVE

To externally validate the RENAL, PADUA and SPARE nephrometry scoring systems for use in retroperitoneal robot-assisted partial nephrectomy (RAPN).

MATERIALS AND METHODS

Nephrometry scores were calculated for 322 consecutive patients receiving retroperitoneal RAPN at a tertiary referral centre from 2017. Patients with multiple tumours were excluded. Scores were correlated with peri-operative outcomes, including the trifecta (warm ischaemia time <25 min, no peri-operative complications and a negative surgical margin), both as continuous and categorical variables. Comparisons were performed using Spearman correlation and ability to predict the trifecta was assessed using binomial logistical regression.

RESULTS

All three scoring systems correlated significantly with the main variables (operating time, warm ischaemia time and estimated blood loss), both as continuous and categorical variables. Only PADUA and SPARE were able to predict achievement of the trifecta (PADUA area under the curve [AUC] 0.623, 95% confidence interval [CI] 0.559-0.668; SPARE AUC 0.612, 95% CI 0.548-0.677).

CONCLUSION

This study validates the RENAL, PADUA and SPARE scoring systems to predict key intra-operative outcomes in retroperitoneal RAPN. Only PADUA and SPARE were able to predict achievement of the trifecta. As a simplified version of the PADUA scoring system with comparable outcomes, we recommend using the SPARE system.

Diagnostic renal mass biopsy is associated with individual categories of PADUA and RENAL nephrometry scores: Analysis of diagnostic and concordance rates with surgical resection

BACKGROUND

Renal mass biopsy (RMB) is a safe and accurate method for diagnosis and clinical management of renal masses. However, the non-diagnostic rate is a limiting factor. We tested the hypothesis that imaging characteristics and anatomic complexity of the mass may impact RMB diagnostic outcome using the preoperative aspects and dimensions used for an anatomical (PADUA) classification and radius-exophytic/endophytic-nearness-anterior/posterior-location (RENAL) score.

MATERIAL AND METHODS

Single institution, retrospective study of 490 renal masses from 443 patients collected from 2001 to 2018. Outcome measurements include (1) diagnostic and concordance rates amongst RMB types and RMB with surgical resection specimens; (2) association between diagnostic RMB and anatomical complexity of renal masses. The analysis was conducted in unselected masses and small renal masses (SRMs).

RESULTS

RMB was performed by fine needle aspiration (FNA), core needle biopsy (CNB), or both (FNA+CNB). Non-diagnostic rate was significantly higher for FNA compared to CNB and FNA+CNB in both unselected and SRMs. Subset analysis in the FNA+CNB group showed similar diagnostic rates for FNA and CNB. In unselected masses, specificity for FNA, CNB, and FNA+CNB was 100%. Sensitivity was higher for CNB (90.1%, P = 0.002) and FNA+CNB (96.3%, P = 0.004) compared to FNA (66.7%). For unselected masses, endophytic growth predicted a non-diagnostic CNB. R.E.N.A.L location entirely between the polar lines (central) and entirely above the upper polar line predicted a diagnostic CNB. Sonography-guidance predicted a diagnostic FNA. For SRMs, non-diagnostic CNB was associated with endophytic growth, while diagnostic CNB was associated with renal sinus invasion and operator experience. More cystic masses were sampled by FNA, but diagnostic results were similar for FNA and CNB.

CONCLUSIONS

Endophytic growth consistently predicted a non-diagnostic CNB in unselected and SRMs, whereas sonography-guidance predicted a diagnostic FNA. Cystic masses could be adequately sampled by FNA.

The associations of RENAL, PADUA and C-index nephrometry scores with perioperative outcomes and postoperative renal function in minimally invasive partial nephrectomy

OBJECTIVE

This study aimed to assess the utility of the radius, exophytic/endophytic, nearness, anterior/posterior, location (RENAL); preoperative aspects and dimensions used for an anatomic evaluation (PADUA), and centrality index (C-index) scores for the outcomes of partial nephrectomy (PN).

MATERIAL AND METHODS

The patients who underwent PN with contrast-enhanced preoperative imaging from January 2015 to June 2018 were identified. The RENAL, PADUA, and C-index scores were assigned. The correlation between these scoring systems and perioperative and long-term renal functional outcomes were evaluated.

RESULTS

A total of 78 patients were included in the study (58 men and 20 women; age, 58±11.4 years). Median warm ischemia time (WIT), estimated blood loss (EBL), and operation time (OT) were 26 min, 115 mL, and 140 min, respectively. The RENAL score was related to WIT, EBL, and OT (p<0.001, p=0.003, and p=0.023, respectively). The PADUA score was associated with WIT, EBL, and OT (p<0.001, p=0.013, and p=0.005, respectively). The C-index score was correlated with WIT, EBL, and OT (p<0.001, p=0.010, and p=0.001, respectively). The C-index score also correlated with the percentage change in the estimated glomerular filtration rate (p=0.037). However, on univariable and multivariable regression analyses, only WIT significantly affected the postoperative estimated glomerular filtration rate reduction.

CONCLUSION

The RENAL, PADUA, and C-index scores were significantly associated with perioperative outcomes of PN. In addition, the C-index score was correlated with long-term renal functional outcomes.

Multi-institutional Retrospective Validation and Comparison of the Simplified PADUA REnal Nephrometry System for the Prediction of Surgical Success of Robot-assisted Partial Nephrectomy

BACKGROUND

The use of a nephron-sparing surgery for the treatment of localized renal masses is being pushed to more challenging cases. However, this procedure is not devoid of risks, and the Radius, Exophytic/Endophytic, Nearness, Anterior/Posterior, Location (RENAL) and Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) classifications are commonly employed in the prediction of complications. Recently, the Simplified PADUA REnal (SPARE) scoring system has been proposed with the aim to provide a more simple system, to improve its reproducibility to predict postoperative risks.

OBJECTIVE

We aim to retrospectively validate and compare the proposed new SPARE system in a multi-institutional population.

DESIGN, SETTING, AND PARTICIPANTS

The Transatlantic Robotic Nephron-sparing Surgery (TRoNeS) study group collected data from 737 patients subjected to robot-assisted partial nephrectomy (RAPN) between 2010 and 2016 at three tertiary care referral centers. Of these patients, 536 presented complete demographic and clinical data.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Renal masses were classified according to the SPARE, RENAL, and PADUA nephrometry scores, and surgical success was defined according to the margin, ischemia, and complication scores.

RESULTS AND LIMITATIONS

Of 536 patients, 340 were male; the median age was 61 (53-69) yr and preoperative tumor size was 30 (22-43) mm. The margin, ischemia, and complication score was achieved in 399 of cases (74.4%). All three nephrometry scores were significant predictors of surgical outcomes both in univariate and in adjusted multivariate logistic regression model analysis. In accuracy analysis, the area under the curve (AUC) of the SPARE scoring system (0.73) was significantly higher than those of the PADUA (0.65) and RENAL (0.68) nephrometry scores in predicting surgical success.

CONCLUSIONS

The SPARE score appears to be a promising and reliable score for the prediction of surgical outcomes of RAPN, showing a higher accuracy relative to the traditional PADUA and RENAL nephrometry scores. Further, prospective studies are warranted before its introduction in clinical practice.

PATIENT SUMMARY

The Simplified PADUA REnal (SPARE) score is a reproducible and simple nephrometry score, offering better predictive capabilities of surgical success and complications.

Nephrometry Scores: Can Preoperative Assessment of Sectional Imaging Really Mirror Intraoperative Renal Tumor Anatomy?

INTRODUCTION

To compare RENAL, preoperative aspects and dimensions used for an anatomical (PADUA) classification, and Mayo Adhesive Probability (MAP) scores with the respective intraoperative findings and surgeon's assessment in predicting surgical outcome of patients undergoing partial nephrectomy.

METHODS

Data of 150 eligible patients treated at the University Medical Center Mannheim between 2016 and 2018 were analyzed. Tumors were radiologically and intraoperatively assessed by PADUA, RENAL, and MAP scores and surgeon's assessment. Correlations and regression models were created to predict ischemia time (IT), major complications, and Trifecta (negative surgical margin, IT < 25 min, and absence of major complications).

RESULTS

There were strong correlations between radiological and intraoperative RENAL (r = 0.68; p < 0.001) and PADUA scores (r = 0.72; p < 0.001). Radiological RENAL, PADUA, and MAP scores and surgeon's assessment were independent predictors of Trifecta (OR = 0.71, p = 0.015; OR = 0.77, p = 0.035; OR = 0.65, p = 0.012; OR = 0.40, p = 0.005, respectively). IT showed significant associations with radiological RENAL, PADUA, and surgeon's assessment (OR = 1.41, p = 0.033; OR = 1.34, p = 0.044; OR = 3.04, p = 0.003, respectively). MAP score proved as only independent predictor of major complications (OR = 2.12, p = 0.002).

CONCLUSION

Radiologically and intraoperatively assessed scores correlated well with each other. Intraoperative nephrometry did not outperform radiological scores in predicting outcome confirming the value of the existing systems. MAP score correlates well with surgeon's assessment of perirenal fat and major complications underlining the importance of perirenal fat characteristics.

Three-dimensional nephrometry scoring system: a precise scoring system to evaluate complexity of renal tumors suitable for partial nephrectomy

Purpose

Several nephrometry scoring systems have been developed based on two-dimensional computerized tomography images to quantify anatomical features of renal tumors. We have developed an accurate three-dimensional nephrometry scoring system to respond to the urgent need for advanced systems based on three-dimensional images.

Materials and Methods

We retrospectively reviewed 135 patients who underwent partial nephrectomy in our institution. Stereoscopic models were reconstructed from preoperative computerized tomography images and three-dimensional scores were assigned directly on stereoscopic models. All tumors were analyzed for following features: tumor volume; endophytic tumor proportion; renal vascular variations; tumor’s relationships with urinary collecting system or renal sinus; longitudinal distance from tumor to equatorial plane. Correlation between three-dimensional score and warm ischemic time was calculated compared with existing classical nephrometry scoring systems. The value of nephrometry scoring systems predicting longer warm ischemic time was explored by receiver operating characteristic curves.

Results

Mean tumor volume was 31.25 ml; endophytic volume was less than 50% in 42 cases, more than 50% in 79 cases, and 100% in 14 cases; mean longitudinal distance from tumor to equatorial plane was 1.41 cm; 30 patients (22.2%) presented renal vascular variations; 18 cases (13.3%) involved both urinary collecting system and sinus. Mean three-dimensional score was 8.3. Variance analysis and covariance analysis revealed warm ischemic time a significant association with all evaluated tumor features. Furthermore, three-dimensional scores most highly correlated with warm ischemic time (rs = 0.64, p < 0.001), followed by R.E.N.A.L. scores (rs = 0.21, p = 0.012), centrality index (rs = − 0.20, p = 0.019) and Preoperative Aspects and Dimensions Used for Anatomy score (rs = 0.20, p = 0.019). Area under curve of above nephrometry scoring systems was 0.91, 0.67, 0.68 and 0.67 respectively (p < 0.05).

Conclusions

The three-dimensional scoring system developed in this study was a highly-accurate system to quantify the anatomical features of renal tumors. It was identified to have a value in predicting duration of warm ischemic time.

No ischemia technique, parenchymal preservation and age are the most important determinants of renal function after partial nephrectomy

OBJECTIVE

The aim of the present study was to compare the outcomes of Off-Clamp to On -Clamp approach during robot-assisted partial nephrectomy (RAPN).

MATERIEL AND METHODS

Retrospective study of 940 patients who underwent a RAPN between 2007 and 2015 for cT1a tumors using On-Clamp or Off-Clamp approaches. Patient with solitary kidney or multifocal were excluded. Overall, 103 patients underwent Off-Clamp approach and 37 patients On-Clamp approach. We matched the patients in terms of tumor size, Charlson comorbidity index and R.E.N.A.L. score. At all, 309 patients from the On-Clamp were matched to the Off-Clamp group. We compared the clinic-pathological characteristics, perioperative morbidity and late functional outcomes between the 2 propensity score matched groups. Limitation included retrospective analysis.

RESULTS

After matching, there were no difference in clinic-pathological characteristics in terms of gender, age, race, body mass index, Charlson comorbidity index, American Society of Anesthesiologists score, baseline estimated glomerular filtration rate (e-GFR), tumor size, R.E.N.A.L. score complexity, hilar (H) location between the 2 groups. Regarding perioperative outcomes; while operative time (P=0,4), estimated blood loss (P=0,28), Clavien grade III-IV complications (P=0,8) surgical reoperation (P=1), 30-day readmission (P=1), positive surgical margin (5,5% vs. 5,8%, P=0,9) were comparable between the 2 groups, there were significant difference in excisional volume loss (median, 7,08 vs. 3,51cm³, P<0,01), e-GFR decline (median, -9,7 vs. -2,2ml/min/1,73 m², P<0,01), percent of e-GFR preservation (median, 87% vs. 97%, P<0,01), and CKD upstaging (36,5% vs. 23,3%, P=0,01), Off-Clamp approach (P=0,01), and age (P=0,02) were predictors of renal function preservation, whereas excisional volume loss (OR=1,035, CI 95% (1,015-1,06), P<0,01) predicted upstaging.

CONCLUSION

RAPN for selected renal mass using Off-Clamp approach offered renal functional advantage over On-Clamp, without adding morbidities. While no ischemia technique was associated with less excisional volume loss, Off-Clamp approach, and age were independent predictors of renal function preservation. Clinical significance of these findings in various clinical settings will require further investigation.

The Simplified PADUA REnal (SPARE) nephrometry system: a novel classification of parenchymal renal tumours suitable for partial nephrectomy

OBJECTIVE

To simplify the original Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) classification of renal tumours, generating a new system able to predict equally or better the risk of overall complications in patients undergoing partial nephrectomy (PN); and to test if the addition of the contact surface area (CSA) parameter improves the accuracy of the original PADUA and new Simplified PADUA REnal (SPARE) nephrometry classification systems.

PATIENTS AND METHODS

We analysed the clinical records of 531 patients who underwent PN (open, laparoscopic and robot-assisted) for renal tumours at five tertiary academic referral centres from January 2014 to December 2016. The ability of each variable included in the PADUA classification to predict overall complications was tested using binary logistic regression analysis. The variables that were not statistically significant were excluded from the SPARE classification. In addition to the original PADUA and SPARE systems, another two models were generated adding tumour CSA. Receiver operating characteristic curve analysis was used to compare the ability of the four different models to predict overall complications. Binary logistic regression was used to perform both univariable and multivariable analyses looking for predictors of postoperative complications. Linear regression analysis was used to identify independent predictors of absolute change in estimated glomerular filtration rate (eGFR; ACE).

RESULTS

The SPARE nephrometry score system including: (i) rim location, (ii) renal sinus involvement, (iii) exophytic rate, and (iv) tumour dimension; showed equal performance in comparison with the original PADUA score (area under the curve [AUC] 0.657 vs 0.664). Adding tumour CSA to the original PADUA (AUC 0.661) or to the SPARE (AUC 0.658) scores did not increase the accuracy of either system to predict overall complications. The SPARE system (odds ratio 1.2, 95% confidence interval 1.1-1.3) was an independent predictor of postoperative overall complications. Age (P < 0.001), body mass index (P < 0.001), Charlson Comorbidity Index (P = 0.02), preoperative eGFR (P < 0.001), and tumour CSA (P = 0.005) were independent predictors of ACE. Limitations include the retrospective design and the lack of central imaging review.

CONCLUSIONS

The new SPARE score is comprised of only four variables instead of the original six and its accuracy to predict overall complications is similar to that of the original PADUA score. Addition of tumour CSA was not associated with an increase in prognostic accuracy. The SPARE system could replace the original PADUA score to evaluate the complexity of tumours suitable for PN.

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

Background

Functional 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.

Methods

We 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.

Results

Three, 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.

Conclusions

We 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.

[Evaluation of the Padua and R.E.N.A.L. scores regarding their validity and implication in the perioperative management during partial nephrectomy]

BACKGROUND

 Due to the rapid development of minimally-invasive surgery, there is a broader indication for surgical preservation of renal tissue. Current research suggests that, apart from the size of the tumour, its exact anatomical position should be considered when seeking optimal surgical treatment for individual patients. Therefore, numerous nephrometry scores have emerged, the Padua score and the R.E.N.A.L. score being most commonly used. Based on our patient population, we aimed to shed light on the question which score is best suited to assess the feasibility of nephron-sparing surgery and which can predict complications most accurately.

PATIENTS AND METHODS

 This study included 117 patients treated with partial nephrectomy at the University Hospital in Kiel (UKSH, Campus Kiel) between 2014 and 2017. The imaging results (computed tomography and magnetic resonance tomography) were retrospectively evaluated according to the Padua and R.E.N.A.L. score criteria. In some cases, radical nephrectomy became necessary despite the planned partial nephrectomy. We evaluated group differences regarding both nephrometry scores in these cases and the cases without radical nephrectomy. Then we performed correlation analyses regarding score outcome, operation time as well as perioperative, postoperative and overall complications.

RESULTS

 The tumours requiring treatment by radical nephrectomy (10 out of 117) had significantly higher scores only when the R.E.N.A.L. score was applied (mean difference 1.059, p < 0.05). Both the Padua and the R.E.N.A.L. score were positive correlated with operation time (R.E.N.A.L. score: correlation coefficient 0.284, p < 0.05, Padua score: coefficient 0.312, p < 0.05) as well as perioperative, postoperative and overall complications (R.E.N.A.L. score: coefficient 0.216, p < 0.05, Padua score: coefficient 0.192, p < 0.05).

CONCLUSION

 Each of the examined scores can be used to assess the risk of partial nephrectomy. For our patients, the preoperative application of the R.E.N.A.L. score would have been advantageous. Preoperative nephrometry scores are a useful tool and should be applied in addition to the surgeon's subjective evaluation. There is a lack of prospective studies investigating this issue.

A multi-institutional report of peri-operative and functional outcomes after robot-assisted partial nephrectomy in patients with a solitary kidney

To evaluate peri- and post-operative outcomes after robotic partial nephrectomy (RPN) in patients with a solitary kidney. A multi-institutional database of 1868 patients was used to identify 35 patients with a solitary kidney who underwent RPN at six different centers from 2007 to 2016. Peri-operative outcomes were summarized with descriptive statistics. We assessed the change in eGFR over time with a linear mixed-effects model. Median operative time, ischemia time, and estimated blood loss were 172 min, 16 min, and 113 mL, respectively. There were no positive surgical margins. The median length of stay was 1 day (range 1-7), and over half (54.3%) of patients were discharged one post-operative day 1. Seven post-operative complications occurred in six patients (17.1%); of which four were Clavien I, two were Clavien II, and one was Clavien III. The linear decline in eGFR up to 24 month post-RPN was marginal and not significant (ß = - 0.14; 95% CI = - 0.51, 0.23; p = 0.453), with predicted mean eGFR decreasing from 59.2 to 55.8 mL/min/1.73 m² at 24 months. These results suggest that, in patients with a solitary kidney, RPN is a safe and feasible treatment option. In patients with a solitary kidney, RPN did not significantly compromise renal function for up to 2 years after surgery.

Modified Nephrometry Score With Body Mass Index More Accurately Predicts Ischemic Time in Transabdominal Laparoscopic Partial Nephrectomy for Small Renal Masses

OBJECTIVE

To accurately predict the ischemic time (IT) and select candidates for transabdominal laparoscopic partial nephrectomy (LPN).

METHODS

Transabdominal LPN was performed for 135 Japanese patients with renal masses <7 cm in diameter between 2009 and 2016 by a single surgeon in a single institute. The renal parenchymal sutures were done with a combination of felt, Hem-o-lok and Lapra-Ty. The original R.E.N.A.L. nephreometry score (NS) was modified as follows. In terms of the tumor size (R), 1, 2, and 3 points were given for ≤2.5, 2.5-4, and >4 cm, respectively. For tumor location (A), 1, 2, and 3 points were given for anterior, on the coronal plane, and posterior, respectively.

RESULTS

The median IT was 24.6 minutes. Using the original NS, 64, 65, and 6 patients were categorized into low (4-6), moderate (7-9), and high (10-12) complexity, respectively. With the modified NS, 42, 75, and 18 patients were categorized into low (5-7), moderate (8-11), and high (12-15) complexity, respectively. Pearson's correlation coefficient (R) between the original NS and IT was 0.297, whereas the R was improved to 0.388 when the modified NS was employed. If the modified NS was low complexity, 95.2% achieved IT <30 minutes. Of them, none showed IT ≥30 minutes if the body mass index was <25 kg/m².

CONCLUSION

The modified NS had a better correlation to the IT than the original NS for patients with tumor sizes <7 cm who underwent transabdominal LPN. The modified NS with body mass index is a practical tool to select candidates for transabdominal LPN.

Validation of radius exophytic/endophytic nearness anterior/posterior location and preoperative aspects and dimensions used for an anatomical nephrometric scores in patients undergoing partial nephrectomy for renal cancer: A single-center experience and literature review

Introduction:

Nephrometric scores are used to predict perioperative and postoperative complications, with no uniform results in the current literature.

Materials and Methods:

A retrospective study of 141 patients in a single center who underwent open partial nephrectomy between June 2006 and 2016 for T1a and T1b renal tumor was conducted. Univariate and multivariate analyses were used to evaluate the correlations between preoperative aspects and dimensions used for an anatomical (PADUA) and radius exophytic/endophytic nearness anterior/posterior location (RENAL) scores and their components with pre-, peri-, and post-operative parameters. Linear regression (F-tests) and logical regression models were used to test for significance of the association and predictability of outcomes.

Results:

Total RENAL score (P = 0.032), its components R (P = 0.004), E (P = 0.022), L (P = 0.011), and total PADUA score (P = 0.016) were significantly associated with ischemic time. In postoperative complications, the PADUA components: sinus line location (P = 0.008), lateral/medial rim score (P = 0.029), and collecting system score (P = 0.006) showed significance. None of the variables showed correlation with operation time and change in estimated glomerular filtration rate (eGFR). On multivariate analysis, sinus line location and gender (P = 0.012) showed significance in predicting eGFR changes and RENAL score component: A (P = 0.049) was significant in predicting estimated blood loss. Both RENAL and PADUA components were significantly associated with hospital length of stay.

Conclusion:

Both RENAL and PADUA scores showed important correlation in predicting outcomes. We further demonstrated the importance of knowing the individual components of the scores, which can independently give outcome predictions. The scoring systems can still be improved and standardized for broad clinical use with larger cohort and multicenter-based studies.

The role of RENAL, PADUA and C-index scoring systems in predicting the results of partial nephrectomy without ischemia

OBJECTIVE

To evaluate the feasibility and renoprotective effect of off-clamp partial nephrectomy (PN) by renal scoring systems.

METHODS

After approval of the local ethics committee, the radiological and clinical data of patients with renal masses who underwent PN between January 2012 and January 2017 were evaluated in two university hospitals. Total 132 patients who underwent open surgery and off-clamp technique were included. All patients underwent contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI) preoperatively. Preoperative demographic data, estimated glomerular filtration rate (e-GFR) and hematocrit changes, operation time, tumor volume and hospitalization time from patients were evaluated separately and statistically for each of the three scoring systems.

RESULTS

Our study consisted of 132 patients with a mean age of 53.9 ± 13.9 with 69 male and 63 female. Statistically significant difference between the risk groups in RENAL and PADUA scoring were found according to tumor T stage and tumor volüme (p <0.005). Statistically significant difference was only found between risk groups of RENAL scoring system in e-GFR reduction (p<0.05). There was no statistically significant difference between the groups in the complications of all three classification systems (p > 0.005).

CONCLUSIONS

In our study, all three scoring sytem successfully predicted the surgical complexity ve surgical outcomes and our results indicate that off-clamp PN has similar success and complications rates when compared to the literature. The off-clamp PN must be kept in mind to maintain postoperative renal functions eligible patients.

Perioperative outcomes of zero ischemia radiofrequency ablation-assisted tumor enucleation for renal cell carcinoma: results of 182 patients

BACKGROUND

To evaluate the perioperative outcomes of zero ischemia radiofrequency ablation-assisted tumor enucleation.

METHODS

Patients undergoing zero ischemia radiofrequency ablation-assisted tumor enucleation were retrospectively identified from July 2008 to March 2013. The tumor was enucleated after RFA treatment. R.E.N.A.L., PADUA and centrality index (C-index) score systems were used to assess each tumor case. We analyzed the correlation of perioperative outcomes with these scores. Postoperative complications were graded with Clavien-Dindo system. Multivariate logistic regression analyses were used to assess risk of complications.

RESULTS

Among 182 patients assessed, median tumor size, estimated blood loss, hospital stay and operative time were 3.2 cm (IQR 2.8-3.4), 80 ml (IQR 50-120), 7 days (IQR 6-8) and 100 min (IQR 90-120), respectively. All three scoring systems were strongly correlated with estimated blood loss, hospital stay and operative time. We found 3 (1.6%) intraoperative and 23 (12.6%, 13 [7.1%] Grade 1 and 10 [5.5%] Grade 2 & 3a) postoperative complications. The median follow-up was 55.5 months (IQR 45-70). Additionally, the complexities of R.E.N.A.L., PADUA and C-index scores were significantly correlated with complication grades (P < 0.001; P < 0.001; P < 0.001; respectively). As the representative, R.E.N.A.L. score was an independent predictive factor for postoperative complications and patients with a high complexity had an over 24-fold higher risk compared to those with a low complexity (OR 24.360, 95% CI 4.412-134.493, P < 0.001).

CONCLUSIONS

Zero ischemia radiofrequency ablation-assisted tumor enucleation is considered an effective nephron-sparing treatment. Scoring systems could be useful for predicting perioperative outcomes of radiofrequency ablation-assisted tumor enucleation.

Nephrometry scores and perioperative outcomes following robotic partial nephrectomy

Objectives:

Based on imaging features, nephrometry scoring systems have been conceived to create a standardized and reproducible way to characterize renal tumor anatomy. However, less is known about which of these individual measures are important with regard to clinically relevant perioperative outcomes such as ischemia time (IT), estimated blood loss (EBL), length of hospital stay (LOS), and change in estimated glomerular filtration rate (eGFR) after robotic partial nephrectomy (PN). We aimed to assess the utility of the RENAL and PADUA scores, their subscales, and C-index for predicting these outcomes.

Materials and Methods:

We analyzed imaging studies from 283 patients who underwent robotic PN between 2008 and 2014 to assign nephrometry scores (NS): PADUA, RENAL and C-index. Univariate linear regression was used to assess whether the NS or any of their subscales were associated with EBL or IT. Multivariable linear regression and linear regression models were created to assess LOS and eGFR.

Results:

The three NS were significantly associated with EBL, IT, LOS, and eGFR at 12 months after surgery. All subscales with the exception of anterior/posterior were significantly associated with EBL and IT. Collecting system, renal rim location, renal sinus, exophytic/endophytic, and nearness to collecting system were significant predictors for LOS. Only renal rim location, renal sinus invasion and polar location were significantly associated with eGFR at 12 months.

Conclusions:

Tumor size and depth are important characteristics for predicting robotic PN outcomes and thus could be used individually as a simplified way to report tumors features for research and patient counseling purposes.

Renal Tumor Invasion Depth and Diameter are the Two Most Accurate Anatomical Features Regarding the Choice of Radical Versus Partial Nephrectomy

BACKGROUND AND AIMS

To evaluate simple tumor characteristics (renal tumor diameter and parenchymal invasion depth) compared with more complex classifications, that is, Renal Tumor Invasion Index (RTII) and Preoperative Aspects and Dimensions Used for an Anatomical classification, in predicting the type of nephrectomy (radical vs partial) performed.

MATERIAL AND METHODS

A total of 915 patients who had undergone either partial nephrectomy ( n = 388, 42%) or radical nephrectomy ( n = 527, 58%) were identified from the Helsinki University Hospital kidney tumor database between 1 January 2006 and 31 December 2014. Tumor maximum diameter and depth of invasion into the parenchyma were estimated from computed tomography or magnetic resonance imaging images and compared with Preoperative Aspects and Dimensions Used for an Anatomical and Renal Tumor Invasion Index. Logistic regression and receiver operating curves were used to compare the parameters at predicting the type of nephrectomy.

RESULTS AND CONCLUSION

All the anatomical variables of receiver operating curve/area under the curve analyses were significant predictors for the type of nephrectomy. Parenchymal invasion (area under the curve 0.91; 95% confidence interval, 0.89-0.93), RTII (area under the curve 0.91; 95% confidence interval, 0.89-0.93), and diameter (area under the curve 0.91; 95% confidence interval, 0.89-0.93) performed significantly better than Preoperative Aspects and Dimensions Used for an Anatomical classification (area under the curve 0.88; 95% confidence interval, 0.85-0.89). In multivariable analysis, invasion depth was the best predictor of nephrectomy type (percentage correct, 85.6%). Addition of one anatomic parameter into the model of non-anatomical cofactors improved the accuracy of the model significantly, but the addition of more parameters did not. Parenchymal invasion depth and tumor diameter are the most accurate anatomical features for predicting the nephrectomy type. All potential anatomical classification systems should be tested against these two simple characteristics.

The percentage of resected and ischemic volume determined by a geometric model is a significant predictor of renal functional change after partial nephrectomy

Purpose

The percentage of parenchyma preserved plays a predominant role in predicting renal function after partial nephrectomy (PN). Currently there is no standard method to estimate preserved renal parenchyma. In this study we propose a formula of the percentage of resected and ischemic volume (PRAIV) determined by a geometric model and evaluate the relationships between renal functional change and PRAIV as well as other clinical parameters.

Materials and Methods

We identified 71 patients who underwent open PN between January 2004 and April 2014. Assuming the kidney to be an ellipsoid with bilaterally equal volume and tumor to be a sphere, we calculated PRAIV by integral calculus. Nadir estimated glomerular filtration rate (eGFR) between postoperative 3 and 12 months were recorded. The correlation between percent eGFR reduction, PRAIV, and other clinical parameters were examined.

Results

On univariate analysis, age (p=0.03), depth of tumor invasion (p=0.004), C index (p=0.003), RAIV (p=0.04), and PRAIV (p<0.001) were correlated with percent reduction of eGFR. However, only age (p=0.007) and PRAIV (p<0.001) were significantly correlated with percent reduction of eGFR on multivariate analysis. Depicting these values along the regression line, we found R² was 0.194 and 0.073 for PRAIV and age, respectively.

Conclusions

PRAIV determined by a geometric model is a significant predictor of renal functional change after PN. Using PRAIV, we can estimate percent eGFR reduction preoperatively for better patient consultation and surgical planning.

Simple renal cyst and renal dysfunction: A pilot study using dimercaptosuccinic acid renal Scan

AIM

Little is known about the association between renal cyst and renal dysfunction. We evaluated the deterioration of renal function in patients with unilateral, large, simple renal cysts.

METHODS

Fifty patients with unilateral, simple renal cysts measuring ≥ 4 cm (cyst group) and 50 kidney donors (control group) were enrolled. Dimercaptosuccinic acid (DMSA) renal scans were performed to calculate split renal function. The differences between split renal function were calculated and compared. Clinical factors affecting decreased renal function in the cyst group were assessed.

RESULTS

The mean age of the patients in the cyst group was higher than the control group (59.1 vs 39.2 years; P = 0.001). Patients with renal cysts tended to be diagnosed with hypertension (P = 0.001), However, the two groups did not significantly differ in terms of the other characteristics. The median cyst size was 7.2 cm (range, 4.5-14.2), and 31 of the 50 patients (60.2%) in the cyst group demonstrated decreased renal function in the cystic kidney units (median: 5.8%; range, 0.2-33). Although there were no differences in split renal function (50.1% vs 49.9%; P = 0.629) in the control group, the relative renal function of the cystic kidney units were significantly lower than the contralateral kidney units in the cyst group (48.3% vs 51.7%; P = 0.001). The decrease in relative renal function (>8%) in the cystic kidney units was associated with a higher serum uric acid levels and higher RENAL complexity (P = 0.035 and P = 0.007, respectively).

CONCLUSION

A significant proportion of unilateral, large, simple renal cysts are associated with decreased relative renal function on DMSA renal scans.

The impact of gender difference on operative time in laparoscopic partial nephrectomy for T1 renal tumor and the utility of retroperitoneal fat thickness as a predictor of operative time

BACKGROUND

To investigate the impact of biological gender on operative parameters, especially operative time, in laparoscopic partial nephrectomy (LPN) for T1 renal tumor.

METHODS

One hundred and eleven (28 female and 83 male) patients and 64 (20 female and 44 male) patients with renal tumors suspected to be RCC cT1aN0M0 who underwent retroperitoneal and transperitoneal LPN, respectively, were analyzed. The influence of sex on operative factors including retroperitoneal fat tissue thickness, determined on CT, was analyzed. The correlation between operative time and gender was evaluated by unpaired t-test and linear logistic regression model.

RESULTS

In both retroperitoneal and transperitoneal LPN, the retroperitoneal fat tissue thickness was greater in men than in women. In retroperitoneal LPN, the operative time was significantly longer in men than in women. In contrast, in transperitoneal LPN, no gender difference was observed in regard to the operative time. In retroperitoneal LPN, linear logistic regression assessment showed that gender, retroperitoneal fat tissue thickness, and tumor size were significantly associated with operative time. Coefficient of determination of the prediction model was 0.317.

CONCLUSIONS

The operative time of retroperitoneal LPN is significantly correlated with gender, maximum tumor diameter, and retroperitoneal fat tissue thickness. We have developed a prediction model for the operative time of retroperitoneal LPN based on preoperative parameters. Interestingly, in transperitoneal LPN, a gender difference in operative time was not apparent, and also predicting operative time might be difficult.

Postoperative Urinary Leakage Following Partial Nephrectomy for Renal Mass: Risk Factors and a Proposed Algorithm for the Diagnosis and Management

OBJECTIVES

To evaluate the current incidence, risk factors, management, and long-term follow-up of urinary leakage following partial nephrectomy, in order to propose an algorithm for diagnosis and evaluation of postoperative urinary leakage.

MATERIALS AND METHODS

The study included 752 patients who underwent elective partial nephrectomies for renal masses between the years 1988 and 2013. Patients' demographics, clinico-pathologic variables, and operative details were collected retrospectively. The associations between urinary leakage and patients' variables were assessed by univariate and multivariate analyses.

RESULTS

Of the 752 patients, 21 (2.8%) experienced urinary leakage; 4 of the 21 patients with urinary leakage had spontaneous resolution, 1 patient underwent nephrectomy, and 16 patients were treated by retrograde ureteral stents insertion. One of them necessitated insertion of an additional percutaneous nephrostomy and another one deserved concomitant percutaneous drainage of a perirenal urinoma. The average period of time that elapsed from the operation until the insertion of stent was 8.5 ± 4.5 days. Stents were removed 68 ± 20.5 days postoperatively. None of the patients had either persistent or repeated leakage. On univariate analysis, hilar renal masses (p < 0.04) and higher preoperative creatinine levels (p < 0.01) were found to be associated with higher rates of urinary leakage. None of these variables was significant on a multivariate analysis. Review of the urinary leakage rate over time revealed it has been constantly decreasing over time, from 4% in early cases to 1.3% among the most recent ones.

CONCLUSION

None of the preoperative variables that were examined in this study was significantly associated with increased risk of urinary leakage. However, cumulative surgical experience was associated with lower rates of urinary leakage, suggesting that the decrease in its incidence is related to the improved surgical skills, rather than to differences in tumors' or patients' characteristics.

[Modern imaging of renal tumors - application in diagnostics and therapy. Characterization, operation planning and therapy monitoring of renal lesions]

This article elucidates the various tools used for the diagnostics and characterization of renal lesions. The advantages and limitations of ultrasound, contrast-enhanced ultrasound (CEUS), computed tomography (CT) and magnetic resonance imaging (MRI) are presented and discussed. In addition, modern imaging features of CT and MRI, such as iodine quantification in CT as well as diffusion-weighted and perfusion imaging in MRI are presented. Lastly, recent developments in standardized reporting of renal tumors regarding the intraoperative surgical risk are presented.

Diameter-Axial-Polar Nephrometry is Predictive of Surgical Outcomes Following Partial Nephrectomy

This study sought to evaluate the predictive value of the DAP (diameter-axial-polar) nephrometry system on surgical outcomes following partial nephrectomy (PN).This was a retrospective study of 237 patients who underwent open or minimally invasive PN for renal tumors at a single tertiary care center between 2009 and 2013. The primary outcomes included ischemia time >20 minutes and percentage of estimated glomerular filtration rate (eGFR) decline >10%. Statistical analysis was performed to study associations and predictions.The DAP sum score exhibited a statistically significant correlation with ischemia time, operative time (OT), estimated blood loss (EBL), length of hospital stay (LOS), and percent change in eGFR. The DAP sum score (odds ratio [OR]: 1.749; 95% confidence interval [CI] 1.379-2.220; P < 0.001) and conventional laparoscopy and laparo-endoscopic single-site (CL&LESS) surgery versus the open surgical approach (OR: 5.736; 95% CI: 2.529-13.011; P < 0.001) independently predicted an ischemia time >20 minutes. Similarly, the DAP sum score (OR: 1.297; 95% CI 1.051-1.602; P = 0.016), age-weighted Charlson comorbidity index (CCI) (OR: 4.730; 95% CI 1.463-15.291; P = 0.009), EBL (OR 2.433; 95% CI 1.095-5.407; P = 0.029), and ischemia time (OR 3.332; 95% CI 1.777-6.249; P < 0.001) were identified as independent predictors of eGFR decline >10%. Furthermore, the DAP score × ischemia time interactions were statistically significant (P < 0.001).We confirmed the predictive value of the DAP nephrometry score with respect to ischemia time and renal functional decline in an independent external cohort of patients undergoing PN. The effect of the DAP score on renal functional decline partially depends on that of ischemia time, and the individual component DAP scores may have different effects on clinical outcomes.

A Literature Review of Renal Surgical Anatomy and Surgical Strategies for Partial Nephrectomy

CONTEXT

A detailed understanding of renal surgical anatomy is necessary to optimize preoperative planning and operative technique and provide a basis for improved outcomes.

OBJECTIVE

To evaluate the literature regarding pertinent surgical anatomy of the kidney and related structures, nephrometry scoring systems, and current surgical strategies for partial nephrectomy (PN).

EVIDENCE ACQUISITION

A literature review was conducted.

EVIDENCE SYNTHESIS

Surgical renal anatomy fundamentally impacts PN surgery. The renal artery divides into anterior and posterior divisions, from which approximately five segmental terminal arteries originate. The renal veins are not terminal. Variations in the vascular and lymphatic channels are common; thus, concurrent lymphadenectomy is not routinely indicated during PN for cT1 renal masses in the setting of clinically negative lymph nodes. Renal-protocol contrast-enhanced computed tomography or magnetic resonance imaging is used for standard imaging. Anatomy-based nephrometry scoring systems allow standardized academic reporting of tumor characteristics and predict PN outcomes (complications, remnant function, possibly histology). Anatomy-based novel surgical approaches may reduce ischemic time during PN; these include early unclamping, segmental clamping, tumor-specific clamping (zero ischemia), and unclamped PN. Cancer cure after PN relies on complete resection, which can be achieved by thin margins. Post-PN renal function is impacted by kidney quality, remnant quantity, and ischemia type and duration.

CONCLUSIONS

Surgical renal anatomy underpins imaging, nephrometry scoring systems, and vascular control techniques that reduce global renal ischemia and may impact post-PN function. A contemporary ideal PN excises the tumor with a thin negative margin, delicately secures the tumor bed to maximize vascularized remnant parenchyma, and minimizes global ischemia to the renal remnant with minimal complications.

PATIENT SUMMARY

In this report we review renal surgical anatomy. Renal mass imaging allows detailed delineation of the anatomy and vasculature and permits nephrometry scoring, and thus precise, patient-specific surgical planning. Novel off-clamp techniques have been developed that may lead to improved outcomes.

Renal Ischemia and Function After Partial Nephrectomy: A Collaborative Review of the Literature

CONTEXT

Partial nephrectomy (PN) is the current gold standard treatment for small localized renal tumors.; however, the impact of duration and type of intraoperative ischemia on renal function (RF) after PN is a subject of significant debate.

OBJECTIVE

To review the current evidence on the relationship of intraoperative ischemia and RF after PN.

EVIDENCE ACQUISITION

A review of English-language publications on renal ischemia and RF after PN was performed from 2005 to 2014 using the Medline, Embase, and Web of Science databases. Ninety-one articles were selected with the consensus of all authors and analyzed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria.

EVIDENCE SYNTHESIS

The vast majority of reviewed studies were retrospective, nonrandomized observations. Based on the current literature, RF recovery after PN is strongly associated with preoperative RF and the amount of healthy kidney parenchyma preserved. Warm ischemia time (WIT) is modifiable and prolonged warm ischemia is significantly associated with adverse postoperative RF. Available data suggest a benefit of keeping WIT <25min, although the level of evidence to support this threshold is limited. Cold ischemia safely facilitates longer durations of ischemia. Surgical techniques that minimize or avoid global ischemia may be associated with improved RF outcomes.

CONCLUSIONS

Although RF recovery after PN is strongly associated with quality and quantity of preserved kidney, efforts should be made to limit prolonged WIT. Cold ischemia should be preferred when longer ischemia is expected, especially in presence of imperative indications for PN. Additional research with higher levels of evidence is needed to clarify the optimal use of renal ischemia during PN.

PATIENT SUMMARY

In this review of the literature, we looked at predictors of renal function after surgical resection of renal tumors. There is a strong association between the quality and quantity of renal tissue that is preserved after surgery and long-term renal function. The time of interruption of renal blood flow during surgery is an important, modifiable predictor of postoperative renal function.

Use of RENAL nephrometry scores for predicting tumor upgrading between core biopsies and surgical specimens: a prospective ex vivo study

Determination of Fuhrman grade (FG) on biopsies of renal masses is relatively inaccurate, being prone to underestimating the true grade as ascertained from surgical specimens. This study evaluated whether anatomical features of tumors could predict tumor upgrading between core biopsies and surgical specimens. We prospectively enrolled 249 patients undergoing surgical resection of solid renal masses at our institution from 2012 to 2013. Tumor anatomical features were defined using RENAL nephrometry scores. Two peripheral and 1 central ex vivo core biopsies were taken from surgical specimens with an F18-gauge needle. Logistic regression was used to assess associations between covariates and FG upgrading. A comprehensive nomogram was constructed to quantitate the probability of tumor upgrading. The median tumor size was 4.75 cm and FG upgrading occurred in 43.6% of cases. In tumors of low, intermediate, and high complexity, the risk of FG upgrading was 22.0%, 47.6%, and 50.6%, respectively. According to multivariate analyses, anatomical features R (radius) and L (location) scores correlated significantly with FG upgrading. A combination of anatomical features and core biopsy findings predicted tumor upgrading with an accuracy of 0.884. With a threshold of 30%, our nomogram identified 92.4% of cases with upgrading; however, it overrated 26.8% of patients without upgrading. This ex vivo prospective study demonstrated that RENAL nephrometry score can aid prediction of FG upgrading between core biopsies and surgical specimens. Our nomogram uses anatomical features to predict true FG from renal biopsies.

Investigating the association between polymorphisms in connective tissue growth factor and susceptibility to colon carcinoma

There have been numerous studies on the gene expression of connective tissue growth factor (CTGF) in colorectal cancer, however very few have investigated polymorphisms in this gene. The present study aimed to determine whether single nucleotide polymorphisms (SNPs) in the CTGF gene are associated with a higher susceptibility to colon cancer and/or an invasive tumor growth pattern. The CTGF gene was genotyped for seven SNPs (rs6918698, rs1931002, rs9493150, rs12526196, rs12527705, rs9399005 and rs12527379) by pyrosequencing. Formalin-fixed paraffin-embedded tissue samples (n=112) from patients diagnosed with colon carcinoma, and an equal number of blood samples from healthy controls, were selected for genomic DNA extraction. The complexity index was measured using images of tumor samples (n=64) stained for cytokeratin-8. The images were analyzed and correlated with the identified CTGF SNPs and clinicopathological parameters of the patients, including age, gender, tumor penetration, lymph node metastasis, systemic metastasis, differentiation and localization of tumor. It was demonstrated that the frequency of the SNP rs6918698 GG genotype was significantly associated (P=0.05) with an increased risk of colon cancer, as compared with the GC and CC genotypes. The other six SNPs (rs1931002, rs9493150, rs12526196, rs12527705, rs9399005 and rs12527379) exhibited no significant difference in the genotype and allele frequencies between patients diagnosed with colon carcinoma and the normal healthy population. A trend was observed between genotype variation at rs6918698 and the complexity index (P=0.052). The complexity index and genotypes for any of the studied SNPs were not significantly correlated with clinical or pathological parameters of the patients. These results indicate that the rs6918698 GG genotype is associated with an increased risk of developing colon carcinoma, and genetic variations at the rs6918698 are associated with the growth pattern of the tumor. The present results may facilitate the identification of potential biomarkers of the disease in addition to drug targets.

The association between the anatomical features of renal tumours and the functional outcomes of robot-assisted partial nephrectomy

INTRODUCTON

We evaluated the the association between PADUA scores and postoperative renal function (after robot-assisted partial nephrectomy [RAPN]) and between PADUA scores and warm ischemic time (during RAPN).

METHODS

We reviewed the clinical records of 106 patients who underwent RAPN for a single localized renal tumour between April 2009 and June 2012. Postoperative renal function was evaluated using estimated glomerular filtration rate (eGFR) in 85 patients who were followed for at least 6 months. PADUA scores for renal tumours were calculated using contrast-enhanced computed tomography images, if needed, along with magnetic resonance images in some cases.

RESULTS

A PADUA score ≥10 and WIT ≥30 minutes were observed in 18 (17.0%) and 51 (48.1%) cases, respectively. PADUA scores were significantly correlated with WIT (p = 0.019) and percent change in eGFR at 6 months postoperatively (p = 0.005). PADUA score (continuous variable, odds ratio [OR] 1.694, p = 0.007) and the high-risk group (PADUA score ≥10) (OR 5.429; p = 0.020) were significantly associated with a WIT of ≥30 minutes by multivariate analysis. A 1-point increase in the PADUA score was associated with an eGFR decrease of >20% at 6 months after RAPN (OR 1.799; p = 0.076). In addition, a PADUA score ≥10, or high risk, (OR 13.965; p = 0.003) was an independent predictor of an eGFR decrease of >20% at 6 months after RAPN.

CONCLUSIONS

The PADUA classification can reliably predict WIT and postoperative renal functional outcome after RAPN. Furthermore, the study suggests that anatomical aspects of renal tumours are associated with functional outcome after RAPN.