Impact of Implementation of Standardized Criteria in the Assessment of Complication Reporting After Robotic Partial Nephrectomy: A Systematic Review.

The definition of a surgical complication still lacks standardization, hampering evaluation of surgical performance in this regard. Over the years, efforts to address this issue have been carried out to improve reporting of outcomes. In 2012, the European Association of Urology (EAU) proposed a standardized reporting tool for urological complications. The aim of this study was to evaluate the impact of those recommendations on complication reporting for patients undergoing robotic partial nephrectomy (RPN). A comprehensive systematic review of all English language publications on RPN was carried out. We followed the Preferred Reporting Items for Systematic Review and Meta-Analyses statement and Agency for Healthcare Research and Quality guidelines in evaluating articles retrieved from the PubMed, Scopus, and Web of Science databases (January 1, 2000 to October 31, 2016; updated June 2017). The quality of reporting and grading complications was assessed according to the EAU recommendations. Temporal comparison revealed an improvement in outcome reporting in terms of mortality rates and causes of death (p=0.05), definition of complications (p<0.001), procedure-specific complications (p=0.02), severity grade (p<0.001), postoperative complications presented by grade/complication type (p<0.001), and risk factors (p<0.001). Our analysis demonstrates an improvement in complication reporting and grading after the EAU recommendation on RPN. PATIENT SUMMARY: Complications are unexpected events that could negatively impact a patient's outcomes after surgery, but there is no agreement on the definition and reporting of complications. In 2012, the European Association of Urology proposed a standardized reporting tool for urological complications. This study shows an improvement in the way physicians report complications after robotic partial nephrectomy. The results underline the importance of standardization in medicine to improve clinical research.

Impact of Renal Hilar Control on Outcomes of Robotic Partial Nephrectomy: Systematic Review and Cumulative Meta-analysis.

CONTEXT: During robotic partial nephrectomy (RPN), various techniques of hilar control have been described, including on-clamp, early unclamping, selective/super-selective clamping, and completely-unclamped RPN. OBJECTIVE: To evaluate the impact of various hilar control techniques on perioperative, functional, and oncological outcomes of RPN for tumors. EVIDENCE ACQUISITION: We conducted a systematic literature review and meta-analysis of all comparative studies on various hilar control techniques during RPN using PubMed, Scopus, and Web of Science according to the Preferred Reporting Items for Systematic Review and Meta-analysis statement, and Methods and Guide for Effectiveness and Comparative Effectiveness Review of the Agency for Healthcare Research and Quality. Cumulative meta-analysis of comparative studies was conducted using Review Manager 5.3. EVIDENCE SYNTHESIS: Of 987 RPN publications in the literature, 19 qualified for this analysis. Comparison of off-clamp versus on-clamp RPN (n=9), selective clamping versus on-clamp RPN (n=3), super selective clamping versus on-clamp RPN (n=5), and early unclamped versus on-clamp (n=3) were reported. Patients undergoing RPN using off-clamp, selective/super selective, or early unclamp techniques had higher estimated blood loss compared with on-clamp RPN (weight mean difference [WMD]: 47.83, p=0.000, WMD: 41.06, p=0.02, and WMD: 37.50, p=0.47); however, this did not seem clinically relevant, since transfusion rates were similar (odds ratio [OR]: 0.98, p=0.95, OR: 0.72, p=0.7, and OR: 1.36, p=0.33, respectively). All groups appeared similar with regards to hospital stay, transfusions, overall and major complications, and positive cancer margin rates. Short- and long-term renal functional outcomes appeared superior in the off-clamp and super selective clamp groups compared with the on-clamp RPN cohort. CONCLUSIONS: Off-clamp, selective/super selective clamp, and early unclamp hilar control techniques are safe and feasible approaches for RPN surgery, with similar perioperative and oncological outcomes compared with on-clamp RPN. Minimizing global renal ischemia may provide superior renal function preservation. However, higher quality data are necessary for definitive conclusions in this regard. PATIENT SUMMARY: The objective of partial nephrectomy is to treat the cancer while maximizing renal function preservation. Clamping the main vessels is done primarily to reduce the blood loss during partial nephrectomy; however, vascular clamping can compromise kidney function. In order to avoid clamping, various techniques have been described. Our analysis showed that techniques that avoid main renal artery clamping during RPN are associated with better renal function preservation, yet deliver non-inferior perioperative and oncological outcomes as compared with RPN procedures that clamp the main vessels.

Juxtatumoral perinephric fat analysis in clear cell renal cell carcinoma.

PURPOSE: The purpose of the study was to evaluate the feasibility of using contrast-enhanced computed tomography (CECT)-based texture analysis (CTTA) metrics to differentiate between juxtatumoral perinephric fat (JPF) surrounding low-grade (ISUP 1-2) versus high-grade (ISUP 3-4) clear cell renal cell carcinoma (ccRCC). METHODS: In this IRB-approved study, we retrospectively queried the surgical database between June 2009 and April 2016 and identified 83 patients with pathologically confirmed ccRCC (low grade: n = 54, mean age = 61.5 years, 18F/35M; high grade n = 30, mean age = 61.7 years, 8F/22M) who also had pre-operative multiphase CT acquisitions. CT images were transferred to a 3D workstation, and nephrographic phase JPF regions were manually segmented. Using an in-house developed Matlab program, a CTTA panel comprising of texture metrics extracted using six different methods, histogram, 2D- and 3D-Gray-level co-occurrence matrix (GLCM) and Gray-level difference matrix (GLDM), and 2D-Fast Fourier Transform (FFT) analyses, was applied to the segmented images to assess JPF textural heterogeneity in low- versus high-grade ccRCC. Univariate analysis and receiver-operator characteristics (ROC) analysis were used to assess interclass differences in texture metrics and their prediction accuracy, respectively. RESULTS: All methods except GLCM consistently revealed increased heterogeneity in the JPF surrounding high- versus low-grade ccRCC. FFT showed increased complexity index (p < 0.01). Histogram analysis showed increased kurtosis and positive skewness in (p < 0.03), and GLDM analysis showed decreased measure of correlation coefficient (MCC) (p < 0.04). Several of the GLCM metrics showed statistically significant (p < 0.04) textural differences between the two groups, but with no consistent trend. ROC analysis showed that MCC in GLCM analysis had an area under the curve of 0.75. CONCLUSIONS: Our study suggests that CTTA of ccRCC shows statistically significant textural differences in JPF surrounding high- versus low-grade ccRCC.

Impact of Host Factors on Robotic Partial Nephrectomy Outcomes: Comprehensive Systematic Review and Meta-Analysis.

PURPOSE: Host factors (tumor size/complexity, patient comorbidities) impact outcomes of robotic partial nephrectomy. We report a comprehensive systematic review and meta-analysis to critically evaluate the impact of host factors on operative, perioperative, functional, oncologic and survival outcomes of robotic partial nephrectomy. MATERIALS AND METHODS: All full text English language publications on robotic partial nephrectomy comparing host factors were evaluated. We followed the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses) statement and AHRQ (Agency for Healthcare Research and Quality) guidelines to evaluate PubMed®, Scopus® and Web of Science® databases (January 1, 2000 to June 31, 2017). Weighted mean difference and odds ratio were used to compare continuous and dichotomous variables, respectively. Sensitivity analyses were performed as needed. To condense the sheer volume of analyses the data are presented using novel summary forest plots. This study is registered with PROSPERO, number CRD42017062712. RESULTS: Our meta-analysis evaluated 41 studies including 10,506 patients. In terms of tumor factors, compared to patients with complex tumors, those with noncomplex tumors had lesser operating room time (WMD -44.95, p=0.003), estimated blood loss (WMD -160, p <0.003), warm ischemia time (WMD -8.56, p ≤0.00001) and postoperative complications (OR 0.42, p=0.01). Tumors larger than 4 cm were associated with greater operating room time (WMD 30.11, p ≤0.00001), estimated blood loss (WMD 39.26; 95% CI 28.77, 49.74; p ≤0.00001), warm ischemia time (WMD 5.17, p ≤0.00001), transfusions (OR 3.15, p=0.003), postoperative complications (OR 1.88, p=0.004) and length of stay (WMD 0.56, p=0.0004). Hilar tumors involved greater estimated blood loss (WMD 51.34, p=0.03), warm ischemia time (WMD 8.17, p ≤0.00001) and conversion to open partial nephrectomy (OR 14.14, p=0.006). Tumor location, anterior vs posterior, did not impact robotic partial nephrectomy outcomes. As for patient factors, older patients (70 years or older) trended nonsignificantly toward greater percentage decrease of estimated glomerular filtration rate and overall mortality. The abnormal body mass index cohort reported greater operating room time (WMD 13.47, p <0.001), estimated blood loss (WMD 45.44, p <0.0001) and postoperative complications (OR 1.48, p=0.03). The chronic kidney disease cohort had a lesser reduction in postoperative percentage estimated glomerular filtration rate (WMD 7.16; 95% CI 2.74, 11.59; p=0.002) and increased postoperative complications (OR 2.05; 95% CI 1.47, 2.85). CONCLUSIONS: Robotic partial nephrectomy outcomes are impacted by host factors, including tumor and patient characteristics. Awareness of this increased risk and its mitigation with expert patient selection are important for excellent robotic partial nephrectomy outcomes. Our meta-analysis provides comprehensive, objective, summary data of 10,506 patients, detailing discrete outcomes for discrete host factors to better inform urologists and patients considering robotic partial nephrectomy.

Impact of Surgical Factors on Robotic Partial Nephrectomy Outcomes: Comprehensive Systematic Review and Meta-Analysis.

PURPOSE: Utilization of robotic partial nephrectomy has increased significantly. We report a literature wide systematic review and cumulative meta-analysis to critically evaluate the impact of surgical factors on the operative, perioperative, functional, oncologic and survival outcomes in patients undergoing robotic partial nephrectomy. MATERIALS AND METHODS: All English language publications on robotic partial nephrectomy comparing various surgical approaches were evaluated. We followed the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses) statement and AHRQ (Agency for Healthcare Research and Quality) guidelines to evaluate PubMed®, Scopus® and Web of Science™ databases (January 1, 2000 to October 31, 2016, updated June 2017). Weighted mean difference and odds ratio were used to compare continuous and dichotomous variables, respectively. Sensitivity analyses were performed as needed. To condense the sheer volume of analyses, for the first time data are presented using novel summary forest plots. The study was registered at PROSPERO (https://www.crd.york.ac.uk/prospero/, ID CRD42017062712). RESULTS: Our meta-analysis included 20,282 patients. When open partial nephrectomy was compared to robotic partial nephrectomy, the latter was superior for blood loss (weighted mean difference 85.01, p  <0.00001), transfusions (OR 1.81, p <0.001), complications (OR 1.87, p <0.00001), hospital stay (weighted mean difference 2.26, p = 0.001), readmissions (OR 2.58, p = 0.005), percentage reduction of latest estimated glomerular filtration rate (weighted mean difference 0.37, p = 0.04), overall mortality (OR 4.45, p <0.0001) and recurrence rate (OR 5.14, p <0.00001). Sensitivity analyses adjusting for baseline disparities revealed similar findings. When robotic partial nephrectomy was compared to laparoscopic partial nephrectomy, the former was superior for ischemia time (weighted mean difference 4.21, p <0.0001), conversion rate (OR 2.61, p = 0.002), intraoperative (OR 2.05, p >0.0001) and postoperative complications (OR 1.27, p = 0.0003), positive margins (OR 2.01, p <0.0001), percentage decrease of latest estimated glomerular filtration rate (weighted mean difference -1.97, p = 0.02) and overall mortality (OR 2.98, p = 0.04). Hilar control techniques, selective and unclamped, are effective alternatives to clamped robotic partial nephrectomy. An important limitation is the overall suboptimal level of evidence of publications in the field of robotic partial nephrectomy. No level I prospective randomized data are available. Oxford level of evidence was level II, III and IV in 5%, 74% and 21% of publications, respectively. No study has indexed functional outcomes against volume of parenchyma preserved. CONCLUSIONS: Based on the contemporary literature, our comprehensive meta-analysis indicates that robotic partial nephrectomy delivers mostly superior, and at a minimum equivalent, outcomes compared to open and laparoscopic partial nephrectomy. Robotics has now matured into an excellent approach for performing partial nephrectomy for renal masses.

Histological analysis of the kidney tumor-parenchyma interface.

PURPOSE: During enucleative partial nephrectomy excision is performed adjacent to the tumor edge. To better determine the oncologic propriety of enucleative partial nephrectomy we histologically examined the tumor-parenchyma interface. MATERIALS AND METHODS: Archived hematoxylin and eosin stained slides of 124 nephrectomy specimens were rereviewed. We evaluated representative sections of tumor abutting the renal parenchyma and overlying pseudocapsule/perirenal fat were selected at 4 mm(2) sectors apportioned 1, 2, 3 and 4 mm, respectively, from the tumor edge. RESULTS: Median tumor size was 3.5 cm. Of the tumors 111 were malignant (90%) and 119 (96%) had a pseudocapsule with a median thickness of 0.6 mm. Of malignant and benign tumors 82% and 31%, respectively, had an intrarenal pseudocapsule (p < 0.001). Pseudocapsule invasion was noted in 45% of cancers and 15% of benign tumors (p < 0.04). Of pT1a cancers 36% showed intrarenal pseudocapsule invasion. No patient had positive surgical margins. Intrarenal pseudocapsule invasion correlated with clear cell renal cell carcinoma histology but not with cancer size, grade, necrosis or margin width. Inflammation, nephrosclerosis, glomerulosclerosis and arteriosclerosis decreased with increasing distance from the tumor edge. At 1 mm changes were moderate to severe in 38%, 32%, 20% and 17% of tumors while at 5 mm changes were mild in 2.5%, 0.8%, 0.8% and 4%, respectively (p <0.001). Mean arteriolar diameter decreased with tumor proximity (p < 0.0001). CONCLUSIONS: Most renal cancers have an intrarenal pseudocapsule. Partial nephrectomy excision adjacent to the tumor edge appears to be histologically safe. Because 18% of cancers lacked a discernible intrarenal pseudocapsule and 25% of pT1a cancers showed intrarenal pseudocapsule invasion, extreme care is needed to avoid positive margins during enucleative partial nephrectomy.