The value of renal score in both determining surgical strategies and predicting complications for renal cell carcinoma: A systematic review and meta-analysis

PADRES: a phase 2 clinical trial of neoadjuvant axitinib for complex partial nephrectomy

OBJECTIVE

To report the results of PADRES (Prior Axitinib as a Determinant of Outcome of Renal Surgery, NCT03438708), a study investigating neoadjuvant axitinib for tumours of high complexity with imperative indication for partial nephrectomy (PN).

METHODS

We conducted a single-arm phase II clinical trial of localized (cT1b-cT3M0) clear-cell renal cell carcinoma (RCC) patients with imperative indications for nephron preservation, where PN is a high-risk procedure due to complexity (RENAL score 10-12). Axitinib 5 mg was administered twice daily for 8 weeks with repeat imaging at completion, followed by surgery. The primary outcome was successful completion of planned PN following axitinib treatment. Secondary objectives included changes in tumour diameter, RENAL nephrometry score, renal function and Response Evaluation Criteria in Solid Tumours (RECIST) v1.1, and surgical complications.

RESULTS

Twenty-seven patients were enrolled (median age 69 years). Prior to therapy, twenty patients (74.0%) had ≥ clinical T3a staged tumours. Axitinib resulted in reductions in tumour diameter (7.5 vs 6.2 cm; P < 0.001) and RENAL score (11 vs 10; P < 0.001). Nine patients (33.3%) had partial response based on RECIST and nine (33.3%) were clinically downstaged. PN was performed in twenty patients (74.0%); twenty-five patients (96.2%) had negative margins. Six patients (22.2%) had Clavien III-IV complications. The median change in estimated glomerular filtration rate (preoperative to last follow-up) was 8.5 mL/min/1.73 m2 .

CONCLUSION

Neoadjuvant axitnib resulted in reductions in tumour size and complexity, enabling safe and feasible PN and functional preservation in patients with complex renal masses and imperative indication.

Factors influencing the decision-making in laparoscopic partial nephrectomy for small renal masses

BACKGROUND AND OBJECTIVES

We analyzed the factors affecting the decision on surgical approach such as hilum dissection, vessel clamping, and the warm ischemia time (WIT) in laparoscopic partial nephrectomy (LPN) for small renal masses (SRMs).

METHODS

Patients who underwent LPN for SRMs between 2011 and 2021 in two centers were retrospectively screened. Standardized R.E.N.A.L. nephrometry score (RNS) and each of the components were scored on a Likert scale and the effect on the surgical approach was examined by using them separately.

RESULTS

A total of 133 patients, 85 of whom were on-clamp and 48 were off-clamp, were included in the study. Greater tumor size, low BMI, higher RNS, upper pole tumor, low exophytic rate, and nearness to the collecting system were statistically significant for both on/off-clamp and hilar dissection decisions. In multivariate analysis, greater tumor size, upper pole tumor, lower rate of exophytic part (E2), nearness to the collecting system (N3) were independent risk factors for vessel clamping. Greater tumor size and lower exophytic tumor rate (E2) were independent risk factors for hilum dissection. We could not identify any factor affecting WIT.

CONCLUSION

Individual components of RNS may serve as a better tool for decision-making on vessel clamping and hilum dissection during LPN for SRMs.

AI-generated R.E.N.A.L.+ Score Surpasses Human-generated Score in Predicting Renal Oncologic Outcomes

OBJECTIVE

To determine whether we can surpass the traditional R.E.N.A.L. nephrometry score (H-score) prediction ability of pathologic outcomes by creating artificial intelligence (AI)-generated R.E.N.A.L.+ score (AI+ score) with continuous rather than ordinal components. We also assessed the AI+ score components' relative importance with respect to outcome odds.

METHODS

This is a retrospective study of 300 consecutive patients with preoperative computed tomography scans showing suspected renal cancer at a single institution from 2010 to 2018. H-score was tabulated by three trained medical personnel. Deep neural network approach automatically generated kidney segmentation masks of parenchyma and tumor. Geometric algorithms were used to automatically estimate score components as ordinal and continuous variables. Multivariate logistic regression of continuous R.E.N.A.L. components was used to generate AI+ score. Predictive utility was compared between AI+, AI, and H-scores for variables of interest, and AI+ score components' relative importance was assessed.

RESULTS

Median age was 60years (interquartile range 51-68), and 40% were female. Median tumor size was 4.2 cm (2.6-6.12), and 92% were malignant, including 27%, 37%, and 23% with high-stage, high-grade, and necrosis, respectively. AI+ score demonstrated superior predictive ability over AI and H-scores for predicting malignancy (area under the curve [AUC] 0.69 vs 0.67 vs 0.64, respectively), high stage (AUC 0.82 vs 0.65 vs 0.71, respectively), high grade (AUC 0.78 vs 0.65 vs 0.65, respectively), pathologic tumor necrosis (AUC 0.81 vs 0.72 vs 0.74, respectively), and partial nephrectomy approach (AUC 0.88 vs 0.74 vs 0.79, respectively). Of AI+ score components, the maximal tumor diameter ("R") was the most important outcomes predictor.

CONCLUSION

AI+ score was superior to AI-score and H-score in predicting oncologic outcomes. Time-efficient AI+ score can be used at the point of care, surpassing validated clinical scoring systems.

Preclinical optimization of a diode laser-based clamp-free partial nephrectomy in a large animal model

Kidney cancer is a common urologic malignancy with either laparoscopic (LPN) or robotic partial nephrectomy as therapeutic options of choice for localized tumors. However, renal resection and suturing are challenging steps of the procedure that can lead to complications such as prolonged warm ischemia, bleeding, and urinary fistulas. LPN with a diode laser is an efficient technique due to its cutting and/or coagulation attributes. Surprisingly, key laser features such as wavelength and power remain undefined. Using a large porcine model, we evaluated the laser range of wavelength and power in a clamp-free LPN and compared it to the established gold-standard LPN technique (i.e., cold-cutting and suturing). By analyzing surgery duration, bleeding, presence of urine leak, tissue damage related to the resected renal fragment and the remaining organ, hemoglobin levels, and renal function, we show that an optimized experimental diode laser clamp-free LPN (wavelength, 980 nm; power, 15 W) had shorter surgery time with less bleeding, and better postoperative renal function recovery when compared to the well-established technique. Together, our data indicate that partial nephrectomy with a diode laser clamp-free LPN technique is an improved alternative to the gold-standard technique. Therefore, translational clinical trials towards human patient applications are readily feasible.

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

The R.E.N.A.L score’s relevance in determining perioperative and oncological outcomes: a Middle-Eastern tertiary care center experience

Objective

The aim of this study is to evaluate the significance of the R.E.N.A.L nephrometry scoring system in predicting perioperative and oncological outcomes and determining the surgical approach of choice for kidney tumors.

Patients and Methods: Our study retrospectively reviewed outcomes from the year 2002 to 2017. Mann-Whitney U test was used to compare continuous variables and chi-square test was used to compare categorical variables. Kaplan-Meier estimates and multivariable cox proportional hazard regression were performed to determine an association between the different R.E.N.A.L categories and disease recurrence or mortality.

Results

A total of 325 patients underwent kidney surgery The most common R.E.N.A.L score category in our cohort study was intermediate (41.2%), followed by low, (33.2%) and high (25.5%). Patients with a high R.E.N.A.L score had worse perioperative outcomes compared to those with a low R.E.N.A.L score. High R.E.N.A.L score patients were 3 times more likely to receive blood transfusions compared to those with a low R.E.N.A.L score (19.4% vs 6.3%, p = 0.018), and a statistically significant longer hospital length of stay was also observed between the two groups (median 4.5 vs 4 days, p = 0.0419). In addition, the only predictor of disease recurrence or mortality was a high R.E.N.A.L score (Hazard Ratio (HR) 3.65, 95% Confidence Interval (CI) 1.05–12.7, p = 0.041).

Conclusion

Our study sheds light on the use of R.E.N.A.L nephrometry score in predicting perioperative, postoperative, and oncological outcomes. Such findings may play a role in optimizing surgical approaches and pre-operative patient counseling.

The role of imaging in the management of renal masses

The wide availability of cross-sectional imaging is responsible for the increased detection of small, usually asymptomatic renal masses. More than 50 % of renal cell carcinomas (RCCs) represent incidental findings on noninvasive imaging. Multimodality imaging, including conventional US, contrast-enhanced US (CEUS), CT and multiparametric MRI (mpMRI) is pivotal in diagnosing and characterizing a renal mass, but also provides information regarding its prognosis, therapeutic management, and follow-up. In this review, imaging data for renal masses that urologists need for accurate treatment planning will be discussed. The role of US, CEUS, CT and mpMRI in the detection and characterization of renal masses, RCC staging and follow-up of surgically treated or untreated localized RCC will be presented. The role of percutaneous image-guided ablation in the management of RCC will be also reviewed.

Neoadjuvant and adjuvant immunotherapy in renal cell carcinoma

OBJECTIVE

The treatment landscape for renal cell carcinoma (RCC) is rapidly evolving. The aim of this review is to summarize the randomized-controlled trials evaluating the role of immunotherapy in neoadjuvant or adjuvant setting.

MATERIALS AND METHODS

We searched PubMed, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov for studies including neoadjuvant or adjuvant immunotherapy, and provided a brief overview of the pharmacodynamics of immunotherapy for RCC.

RESULTS

Several drugs are currently under investigation. In the neoadjuvant setting, four studies are evaluating the role of single-agent immunotherapy, one of dual-agent immunotherapy, and four studies the role of immunotherapy in combination with tyrosine kinase inhibitors or anti-interleukin-1 beta. In the adjuvant setting, two studies are evaluating the role of single-agent immunotherapy and two of dual-agent immunotherapy.

CONCLUSIONS

The approval of immune checkpoint inhibition as a front-line therapeutic strategy for advanced RCC has also ultimately led to the investigation of these agents first in the adjuvant and then in the neoadjuvant setting. Currently, there are nine studies aimed to evaluate the role of immunotherapy in the neoadjuvant setting and four studies in the adjuvant setting.

The value of renal score in both determining surgical strategies and predicting complications for renal cell carcinoma: A systematic review and meta-analysis

Objectives

Radical nephrectomy (RN) was the standard treatment for renal cell carcinoma (RCC). However, recent studies have found that partial nephrectomy (PN) could achieve similar effects as radical nephrectomy, and has the advantages of less bleeding and shorter hospital stay. The choice of surgical strategies has become a concern of clinicians, which could be guided by renal score introduced by Kutikov et al Therefore, we conducted this meta‐analysis to clarify the value of renal score of determining surgical strategies and predicting complications.

Methods

The keywords “RENAL score,” “renal nephrometry score,” or “nephrometry score” were used to retrieve electronic databases for relevant literature up to Feb 2020, including PubMed, Web of Science, and the Cochrane library. Surgical strategies and complications are outcome measures. Risk ratio (RR) with 95% confidence intervals (CI) is applied to assess the effect size.

Results

A total of 20 studies met the selection criteria for meta‐analysis. There was significant difference in RN operation rate for each subgroup (low‐moderate: RR = 3.50, 95% Cl = 2.60‐4.71, P < .001; low‐high: RR = 6.29, 95% Cl = 4.40‐9.00, P < .001; moderate‐high: RR = 1.80, 95% Cl = 1.39‐2.32, P < .001).The overall incidence of complications from high renal score group was significantly higher than that in low renal score group (low‐moderate: RR = 1.32, 95% Cl = 1.03‐1.69, P = .026; low‐high: RR = 2.45, 95% Cl = 1.48‐4.07, P = .001; moderate‐high: RR = 1.75, 95% Cl = 1.17‐2.61, P = .007).

Conclusions

This meta‐analysis indicated that renal score is an efficient tool for determining surgical strategies and predicting complications in PN. More prospective research is essential to verify the predictive value of renal score.