Predictors of Positive Surgical Margins after Robot-Assisted Partial Nephrectomy for Localized Renal Tumors: Insights from a Large Multicenter International Prospective Observational Project (The Surface-Intermediate-Base Margin Score Consortium).

Background: To explore predictors of positive surgical margins (PSM) after robotic partial nephrectomy (PN) in a large multicenter international observational project, harnessing the Surface-Intermediate-Base (SIB) margin score to report the resection technique after PN in a standardized way. Methods: Data from consecutive patients with cT1-2N0M0 renal masses treated with PN from September 2014 to March 2015 at 16 tertiary referral centers and included in the SIB margin score International Consortium were prospectively collected. For the present study, only patients treated with robotic PN were included. Uni- and multivariable analysis were fitted to explore clinical and surgical predictors of PSMs after PN. Results: Overall, 289 patients were enrolled. Median (IQR) preoperative tumor size was 3.0 (2.3−4.2) cm and median (IQR) PADUA score was 8 (7−9). SIB scores of 0−2 (enucleation), 3−4 (enucleoresection) and 5 (resection) were reported in 53.3%, 27.3% and 19.4% of cases, respectively. A PSM was recorded in 18 (6.2%) patients. PSM rate was 4.5%, 11.4% and 3.6% in case of enucleation, enucleoresection and resection, respectively. Patients with PSMs had tumors with a higher rate of contact with the urinary collecting system (55.6% vs. 27.3%; p < 0.001) and a longer median warm ischemia time (22 vs. 16 min; p = 0.02) compared with patients with negative surgical margins, while no differences emerged between the two groups in terms of other tumor features (i.e., pathological diameter, PADUA score). In multivariable analysis, only enucleoresection (SIB score 3−4) versus enucleation (SIB score 0−2) was found to be an independent predictor of PSM at final pathology (HR: 2.68; 95% CI: 1.25−7.63; p = 0.04), while resection (SIB score 5) was not. Conclusions: In our experience, enucleoresection led to a higher risk of PSMs as compared to enucleation. Further studies are needed to assess the differential impacts of resection technique and surgeon's experience on margin status after robotic PN.

Impact of Trifecta definition on rates and predictors of "successful" robotic partial nephrectomy for localized renal masses: results from the Surface-Intermediate-Base Margin Score International Consortium.

BACKGROUND: Over the years, five different Trifecta score definitions have been proposed to optimize the framing of "success" in partial nephrectomy (PN) field. However, such classifications rely on different metrics. The aim of the present study was to explore how the success rate of robotic PN, as well as its drivers, vary according to the currently available definitions of Trifecta. METHODS: Data from consecutive patients with cT1-2N0M0 renal masses treated with robotic PN at 16 referral centers from September 2014 to March 2015 were prospectively collected. Trifecta rate was defined for each of the currently available definitions. Multivariable logistic regression analysis was used to evaluate possible predictors of "Trifecta failure" according to the different adopted formulation. RESULTS: Overall, 289 patients met the inclusion criteria. Among the definitions, Trifecta rates ranged between 66.4% and 85.9%. Multivariable analysis showed that predictors for "Trifecta failure" were mainly tumor-related (i.e. tumor's nephrometry) for those Trifecta scores relying on WIT as a surrogate metric for postoperative renal function deterioration (definitions 1,2), while mainly surgery-related (i.e. ischemia time and excision strategy) for those including the percentage change in postoperative eGFR as the functional cornerstone of Trifecta (definitions 3-5). CONCLUSIONS: There was large variability in rates and predictors of "unsuccessful PN" when using different Trifecta scores. Further research is needed to improve the value of the Trifecta metrics, integrating them into routine patient counseling and standardized assessment of surgical quality across institutions.

Impact of surgical approach and resection technique on the risk of Trifecta Failure after partial nephrectomy for highly complex renal masses.

INTRODUCTION: We aimed to compare the outcomes of open vs robotic partial nephrectomy (PN), focusing on predictors of Trifecta failure in patients with highly complex renal masses. PATIENTS AND METHODS: We queried the prospectively collected database from the SIB International Consortium, including 507 consecutive patients with cT1-2N0M0 renal masses treated at 16 high-volume referral centres, to select those with highly complex (PADUA score ≥10) tumors undergoing PN. RT was classified as enucleation, enucleoresection or resection according to the SIB score. Trifecta was defined as achievement of negative surgical margins, no acute kidney injury and no Clavien-Dindo grade ≥2 postoperative surgical complications. Multivariable logistic regression analysis was used to assess independent predictors of Trifecta failure. RESULTS: 113 patients were included. Patients undergoing open PN (n = 47, 41.6%) and robotic PN (n = 66, 58.4%) were comparable in baseline characteristics. RT was classified as enucleation, enucleoresection and resection in 46.9%, 34.0% and 19.1% of open PN, and in 50.0%, 40.9% and 9.1% of robotic PN (p = 0.28). Trifecta was achieved in significantly more patients after robotic PN (69.7% vs. 42.6%, p = 0.004). On multivariable analysis, surgical approach (open vs robotic, OR: 2.62; 95%CI: 1.11-6.15, p = 0.027) and tumor complexity (OR for each additional unit of the PADUA score: 2.27; 95%CI: 1.27-4.06, p = 0.006) were significant predictors of Trifecta failure, while RT was not. The study is limited by lack of randomization; as such, selection bias and confounding cannot be entirely ruled out. CONCLUSIONS: Tumor complexity and surgical approach were independent predictors of Trifecta failure after PN for highly complex renal masses.

Impact of Resection Technique on Perioperative Outcomes and Surgical Margins after Partial Nephrectomy for Localized Renal Masses: A Prospective Multicenter Study.

PURPOSE: The impact of resection technique on partial nephrectomy outcomes is controversial. The aim of this study was to evaluate the pattern of resection techniques during partial nephrectomy and the impact on perioperative outcomes, acute kidney injury, positive surgical margins and the achievement of the Trifecta (negative surgical margins, no perioperative Clavien-Dindo grade 2 or greater surgical complications and no postoperative acute kidney injury). MATERIALS AND METHODS: We prospectively collected data on consecutive patients with cT1-2N0M0 renal masses treated with partial nephrectomy at a total of 16 referral centers from September 2014 to March 2015. After partial nephrectomy the resection technique was classified by the surgeon as enucleation, enucleoresection or resection according to the SIB (Surface-Intermediate-Base) margin scores 0 to 2, 3 or 4 and 5, respectively. Multivariable logistic regression analysis was done to evaluate the potential impact of the resection technique on postoperative surgical complications, positive surgical margins, acute kidney injury and Trifecta achievement. RESULTS: Overall 507 patients were included in analysis. The resection technique was classified as enucleation in 266 patients (52%), enucleoresection in 150 (30%) and resection in 91 (18%). The resection technique (enucleoresection vs enucleation and resection) was the only significant predictor of positive surgical margins. Tumor complexity, surgical approach (open and laparoscopic vs robotic) and resection technique (enucleoresection vs enucleation) were significant predictors of Clavien-Dindo grade 2 or greater surgical complications. The surgical approach (open and laparoscopic vs robotic), the resection technique (enucleoresection vs enucleation) and warm ischemia time were significantly associated with postoperative acute kidney injury and Trifecta achievement. CONCLUSIONS: Resection techniques significantly impact surgical complications, early functional outcomes and positive surgical margins after partial nephrectomy of localized renal masses.

The minimally invasive management of ureteropelvic junction obstruction in horseshoe kidneys.

PURPOSE: Data regarding the treatment of ureteropelvic junction obstruction (UPJO) in horseshoe kidneys are limited. We performed a retrospective analysis of our experience with minimally invasive treatment of UPJO in patients with this anomaly. METHODS: Between March of 1996 and March 2008, 9 patients with horseshoe kidneys were treated for UPJO at our institution. Of these patients, 6 were managed with retrograde endopyelotomy, 2 with laparoscopic pyeloplasty, and one by robotic pyeloplasty. Outcomes of these procedures were retrospectively reviewed. RESULTS: A total of nine patients were available for analysis. Four of six patients who underwent endopyelotomy had available follow-up, with a mean of 56 months. The success rate for these patients was 75%. Two of three patients (67%) in the laparoscopic/robotic cohort were successfully treated with a mean follow-up of 21 months. CONCLUSIONS: UPJO in horseshoe kidneys can pose a therapeutic dilemma. The minimally invasive treatment of these patients is feasible with good success rates for both endopyelotomy and laparoscopic/robotic pyeloplasty.

The effect of the choice of irrigation fluid on cardiac stress during transurethral resection of the prostate: a comparison between 1.5% glycine and 5% glucose.

PURPOSE: Variable amounts of irrigation fluid are absorbed during transurethral prostate resection. Previous studies suggest that cardiac stress occurs as a result of transurethral prostate resection, possibly due to glycine absorption. We performed a prospective, blinded, randomized trial comparing 1.5% glycine with 5% glucose irrigating solution. We assessed whether glycine or glucose irrigation for transurethral prostate resection is associated with cardiotoxicity, as measured by troponin I and echocardiogram changes. MATERIALS AND METHODS: Between December 2001 and March 2003, 250 patients were recruited. Changes in immediate postoperative vs preoperative echocardiogram and serum cardiac troponin I indicated perioperative myocardial stress. Intraoperative irrigating fluid absorption was measured with 1% ethanol as a marker. Operative details recorded were anesthesia type, resection time, resected tissue weight and temperature change. Blood loss was measured with transfusions considered. Postoperatively blood assessments included serum glycine assay. RESULTS: Five patients (4%) in the glycine group and 3 (2%) in the glucose group had significantly increased troponin I after surgery. Of these men 1 per group had myocardial infarction and the remainder had transient ischemia. Logistic regression was used to identify factors associated with an unfavorable outcome, which was recorded as a significant increase in troponin I or ischemic changes on echocardiography. Increasing patient age and blood loss were associated with an unfavorable outcome (OR 1.84 and 1.24, respectively). We noted no significant differences in the 1.5% glycine and 5% glucose groups with regard to troponin I/echocardiogram. However, when the glycine assay was compared with adverse outcomes, an increased glycine assay was found to be associated with echocardiogram changes (p = 0.001) and with increased troponin I levels (relative risk 10.71). CONCLUSIONS: Transurethral prostate resection has an effect on the myocardium perioperatively. Glycine absorption causes echocardiogram changes and it is associated with increased troponin I. Increasing patient age and blood loss are associated with myocardial insult. The risk of increased blood loss was accumulative with each unit lost. Unrecognized blood loss or glycine absorption may explain the increase in morbidity and mortality previously reported in patients who undergo transurethral prostate resection.

Is using ethanol-glycine irrigating fluid monitoring and 'good surgical practice' enough to prevent harmful absorption during transurethral resection of the prostate?

OBJECTIVE: To evaluate the utility of using a tracer of 1% ethanol in 1.5% glycine for the early detection of irrigation fluid absorption during transurethral resection of the prostate (TURP). PATIENTS AND METHODS: In all, 126 men undergoing TURP were irrigated with a solution of 1% ethanol and 1.5% glycine; their expired air was tested for ethanol every 20 min, and again at the end of the procedure. Maximum absorption by the breath-ethanol reading was compared with the serum concentration of absorbed glycine (analysed by anion-exchange chromatography). RESULTS: Complete data on 120 men were assessed; 75% of the men absorbed irrigation fluid, with glycine levels above the normal range. The sodium levels tended to decrease with increasing glycine levels (Spearman's rank correlation coefficient, - 0.57; 120 men) and five men (4%) developed clinical features of the TUR syndrome. There was a weak correlation between breath-ethanol levels and serum glycine levels (Spearman's rank correlation coefficient, 0.54). The experience of the surgeon, the weight of the resected chips, and the operative duration were not significantly predictive of irrigation fluid absorption. CONCLUSIONS: A rising breath-ethanol level indicates irrigation fluid absorption. However, irrigating fluid absorption is unpredictable, supporting the case for alternative, potentially safer irrigants.