Hypertension and diabetes mellitus are not associated with worse renal functional outcome after partial nephrectomy in patients with normal baseline kidney function.

OBJECTIVE: To analyze the association of hypertension and/or diabetes mellitus on renal function after partial nephrectomy in patients with normal baseline kidney function. METHODS: We identified 453 patients with baseline estimated glomerular filtration rate ≥60 that underwent robotic partial nephrectomy for a cT1 renal mass from 2008 to 2014 using a multi-institutional database. The association between estimated glomerular filtration rate and time (pre-partial nephrectomy to 24 months post-partial nephrectomy) was compared between 269 (59.4%) patients with preoperative hypertension and/or diabetes mellitus and 184 (40.6%) patients with neither hypertension nor diabetes mellitus using a multivariable model adjusting for confounders. RESULTS: The estimated glomerular filtration rate significantly decreased over time for both groups compared with baseline (average units/month: 1.8974 hypertension/diabetes mellitus, 1.2163 no hypertension/diabetes mellitus; P < 0.0001), and the estimated glomerular filtration rate decrease per month reduced over time (P < 0.0001). The estimated glomerular filtration rate began to increase at approximately 12 months for the hypertension/diabetes mellitus group, and at approximately 18 months for the no hypertension/diabetes mellitus group. Although a greater initial decline in the estimated glomerular filtration rate after partial nephrectomy was observed for the hypertension/diabetes mellitus group (0.68 units/month), this was not statistically significant (P = 0.0842); and while the rate of recovery from this decline was faster for the hypertension/diabetes mellitus group, this also was not statistically significant (P = 0.0653). The predicted estimated glomerular filtration rate was similar (83 mL/min/1.73 m2 ) for both groups 24 months after partial nephrectomy. CONCLUSIONS: There seems to be no significant association between hypertension, diabetes mellitus and renal functional outcome after partial nephrectomy in patients with normal baseline glomerular filtration rate. Renal function declines after partial nephrectomy, but then it recovers, irrespective of the presence of hypertension or diabetes mellitus.

Predicting Complications Following Robot-Assisted Partial Nephrectomy with the ACS NSQIP® Universal Surgical Risk Calculator.

PURPOSE: We evaluated the predictive value of the ACS NSQIP® (American College of Surgeons National Surgical Quality Improvement Program®) surgical risk calculator in a tertiary referral cohort of patients who underwent robot-assisted partial nephrectomy. MATERIALS AND METHODS: We queried our prospectively maintained, multi-institutional database of patients treated with robot-assisted partial nephrectomy and input the preoperative details of 300 randomly selected patients into the calculator. Accuracy of the calculator was assessed by the ROC AUC and the Brier score. RESULTS: The observed rate of any complication in our cohort was 14% while the mean predicted rate of any complication using the calculator was 5.42%. The observed rate of serious complications (Clavien score 3 or greater) was 3.67% compared to the predicted rate of 4.89%. Low AUC and high Brier score were calculated for any complication (0.51 and 0.1272) and serious complications (0.55 and 0.0352, respectively). The calculated AUC was low for all outcomes, including venous thromboembolism (0.67), surgical site infection (0.51) and pneumonia (0.44). CONCLUSIONS: The ACS NSQIP risk calculator poorly predicted and discriminated which patients would experience complications after robot-assisted partial nephrectomy. These findings suggest the need for a more tailored outcome prediction model to better assist urologists risk stratify patients undergoing robot-assisted partial nephrectomy and counsel them on individual surgical risks.

Robot-assisted partial nephrectomy: continued refinement of outcomes beyond the initial learning curve.

OBJECTIVES: To evaluate trends in peri-operative outcomes of 250 consecutive cases beyond the initial learning curve (LC) of robot-assisted partial nephrectomy (RAPN) among multiple surgeons. PATIENTS AND METHODS: A multi-institutional database was used to evaluate trends in patient demographics (e.g. age, gender, comorbidities), tumour characteristics (e.g. size, complexity) and peri-operative outcomes (e.g. warm ischaemia time [WIT], operating time, complications, estimated blood loss [EBL], trifecta achievement) in consecutive cases 50-300 (n = 960) from 2008 to 2016 among four experienced surgeons. Trends in outcomes were assessed using multivariable regression models adjusted for demographic and tumour-specific variables. Outcomes for cases 50-99 were compared with those for cases 250-300. RESULTS: In the study period RAPN was increasingly performed in patients with larger tumours (ß = 0.001, P = 0.048), hypertension (odds ratio [OR] 1.003; P = 0.008) diabetes (OR 1.003; P = 0.025) and previous abdominal surgery (OR 1.003; P = 0.006). Surgeon experience was associated with more trifecta achievement (OR 1.006; P < 0.001), shorter WIT (ß = -0.036, P < 0.001), less EBL (ß = -0.154, P = 0.009), fewer blood transfusions (OR 0.989, P = 0.024) and a reduced length of hospital stay (ß = -0.002, P = 0.002), but not with operating time (P = 0.243), complications (P = 0.587) or surgical margin status (P = 0.102). Tumour size and WIT in cases 50-99 vs 250-300 were 2.7 vs 3.2 cm (P = 0.001) and 21.4 vs 16.2 min (P < 0.001), respectively. CONCLUSION: Refinement of RAPN outcomes, concomitant with the treatment of a patient population with larger tumours and more comorbidities, occurs after the initial LC is reached. Although RAPN can consistently be performed safely with acceptable outcomes after a small number of cases, improvement in trifecta achievement, WIT, EBL, blood transfusions and a shorter hospitalization continues to occur up to 300 procedures.

Comparison of perioperative and functional outcomes of robotic partial nephrectomy for cT1a vs cT1b renal masses.

OBJECTIVE: To compare perioperative and functional outcomes of patients with cT1a or cT1b renal masses undergoing robotic partial nephrectomy (RPN) in a large multi-institutional study PATIENTS AND METHODS: The present retrospective Institutional Review Board-approved multi-institutional study utilised a prospectively maintained database to identify patients undergoing RPN by six surgeons for a solitary cT1a (n = 1 307) or cT1b (n = 377) renal mass from 2006 to 2016. Perioperative and renal function outcomes at discharge and at a median follow-up of 12.2 months were compared in univariable and multivariable regression analyses adjusting for surgeon performing the procedure and date of surgery. RESULTS: In univariable analysis, cT1b masses were associated with longer operative time (190.0 vs 159.0 min, P < 0.001), longer warm ischaemia time (18.8 vs 15.0 min, P < 0.001), higher estimated blood loss (150.0 vs 100.0 mL, P < 0.001), more intraoperative complications (5.6% vs 2.4%, P = 0.034), and more surgical postoperative complications (10.1% vs 5.7%, P =0.002). Results were similar in multivariable analysis with additional findings including more overall postoperative complications (odds ratio 1.55, P = 0.015) and longer length of stay (P < 0.001) associated with cT1b masses. There were no differences in the risk of progression of chronic kidney disease stage at 12.2 months, positive surgical margins, or major postoperative complications. CONCLUSIONS: Although our study shows a longer operative time, longer warm ischemia time, and higher complication rate for patients undergoing RPN for cT1b renal masses, the magnitude of these differences is small. RPN should be considered for cT1b lesions when anatomical and spatial location allow for a feasible procedure.

Selective arterial clamping does not improve outcomes in robot-assisted partial nephrectomy: a propensity-score analysis of patients without impaired renal function.

OBJECTIVES: To assess the benefit of selective arterial clamping (SAC) as an alternative to main renal artery clamping (MAC) during robot-assisted partial nephrectomy (RAPN) in patients without underlying chronic kidney disease (CKD). PATIENTS AND METHODS: Our study cohort comprised 665 patients without impaired renal function undergoing MAC (n = 589) or SAC (n = 76) during RAPN from four medical institutions in the period 2008-2015. We compared complication rates, positive surgical margin (PSM) rates, and peri-operative and intermediate-term renal functional outcome between 132 patients undergoing MAC and 66 undergoing SAC after 2-to-1 nearest-neighbour propensity-score matching for age, sex, body mass index, RENAL nephrometry score, tumour size, baseline estimated glomerular filtration rate (eGFR), American Society of Anesthesiologists (ASA) score, Charlson comorbidity index (CCI) and warm ischaemia time (WIT). RESULTS: In propensity-score-matched patients, PSM (5.7 vs 3.0%; P = 0.407) and complication rates (13.8 vs 10.6%; P = 0.727) did not differ between the MAC and SAC groups. The incidence of acute kidney injury for MAC vs SAC (25.0 vs 32.0%; P = 0.315) within the first 30 days was similar. At a median follow-up of 7.5 months, the percentage reduction in eGFR (-9.3 vs -10.4%; P = 0.518) and progression to CKD ≥ stage 3 (7.2 vs 8.5%; P = 0.792) showed no difference. CONCLUSIONS: Our study findings show no difference in PSM rates, complication rates or intermediate-term renal functional outcomes between patients with unimpaired renal function who underwent SAC vs those who underwent MAC. When expected WIT is low, the routine use of SAC may not be necessary. Further studies will need to determine the role of SAC in patients with a solitary kidney or with significantly impaired renal function.

Predictors of biochemical recurrence in pT3b prostate cancer after radical prostatectomy without adjuvant radiotherapy.

BACKGROUND: Men with pathologic evidence of seminal vesicle invasion (SVI) at radical prostatectomy (RP) have higher rates of biochemical recurrence (BCR) and mortality. Adjuvant radiotherapy (XRT) has been shown to increase freedom from BCR, but its impact on overall survival is controversial and it may represent overtreatment for some. The present study, therefore, sought to identify men with SVI at higher risk for BCR after RP in the absence of adjuvant XRT. METHODS: We identified 180 patients in our institutional database who underwent RP from 1990 to 2011 who had pT3bN0-1 disease. The Kaplan-Meier method was used to estimate freedom from BCR for the overall cohort and substratified by Gleason score, PSA, surgical margin status, and lymph node positivity. Cox Proportional Hazards models were used to determine demographic and histopathological factors predictive of BCR. Time-dependent ROC curve analysis was conducted to assess the ability of the UCSF-CAPRA score to predict BCR. RESULTS: Median age was 64 years, and 52.8% of patients were preoperative D'Amico high risk. At RP, 41.4% had a positive surgical margin (PSM), and 12.2% had positive lymph nodes (LN). The most common sites of PSM were the peripheral zone (56.8%) and the apex (32.4%). Positive bladder neck margin (HR = 7.01, P = 0.035) and PSA 10-20 versus ≤10 (HR = 1.63, P = 0.047) predicted higher BCR in multivariable analyses. Median follow-up was 26 months, and 2-, 3-, and 5-year BCR-free rates were 56.1%, 49.0%, and 39.5%. Log rank tests showed that freedom from BCR was significantly less for Gleason 9-10, PSA >20, PSM, and N1 patients. The area under curve (AUC) for CAPRA in predicting BCR was 0.713 at 2 years, 0.692 at 3 years, and 0.641 at 5 years. Increasing CAPRA score was associated with an increased risk of BCR (HR = 1.33, P < 0.001). CONCLUSIONS: pT3b prostate cancer is a heterogeneous disease commonly associated with several high-risk features. Stratifying men with SVI by prognostic features (i.e., Gleason, PSA, node status, surgical margin status) and using these features to augment the CAPRA score will improve identification of those at higher risk for BCR that should be strongly considered for adjuvant XRT.

Black race may be associated with worse overall survival in renal cell carcinoma patients.

OBJECTIVE: To examine socio-demographic and treatment variables in an attempt to identify factors associated with survival differences between black and white patients with renal cell carcinoma (RCC). PATIENTS AND METHODS: We identified 79,618 white and 10,604 black patients diagnosed with RCC in the National Cancer Database. We compared the distribution of socio-demographic, presentation and treatment variables between Blacks and Whites and then utilized a multivariable cox proportion hazards regression model to evaluate the contribution of differences in these variables to disparities in overall survival (OS). RESULTS: Black patients were younger (60 vs. 63 years, P< 0.001) and with a lower stage (12.0% vs. 18.8% Stage III-IV P< 0.001). Blacks presented with a higher Charlson-Deyo score (P< 0.001), lower income (P< 0.001), lower education (P< 0.001) and were less likely to receive radical nephrectomy and systemic therapy for stage IV RCC (29.9% vs. 38.8%, P< 0.001). Unadjusted OS was lower for Whites (5-year survival 79% for Blacks and 77% for Whites). However, OS was lower for Blacks when adjusted for all variables (5-year survival 89% for Blacks and 93% for Whites). On multivariable analysis, black race was independently associated with worse OS, HR: 1.09 (95% confidence interval: 1.03, 1.14, P= 0.002). A sensitivity analysis including patients with complete data on tumor grade confirmed our results. CONCLUSION: Our study indicates that black patients present at a younger age and with lower stage RCC, but have worse OS. Blacks experienced disparities in socio-demographic characteristics, clinical presentation, treatment-related factors, and had an independently increased hazard of death.

A Multi-Institutional Analysis of the Effect of Positive Surgical Margins Following Robot-Assisted Partial Nephrectomy on Oncologic Outcomes.

Objective: To determine the effect of positive surgical margins (PSMs) on oncologic outcomes following robot-assisted partial nephrectomy (RAPN) and to identify factors that increase the likelihood of adverse oncologic outcomes. Methods: A multi-institutional database of patients who underwent RAPN with complete follow-up data was used to compare recurrence-free survival (RFS) and overall survival (OS) between 42 (5.1%) patients with a PSM and 797 (94.9%) patients with a negative surgical margin. Analysis was performed with univariable and multivariable Cox proportional hazard regression models adjusting for confounding variables. A Kaplan-Meier method was used to evaluate the relationship between PSM and oncologic outcomes (RFS and OS), and the equality of the curves was assessed using a log-rank test. Results: The rate of PSM was 5.1%. RFS at 12, 24, and 36 months was 97.8%, 95.2%, and 92.9%. OS at 12, 24, and 36 months was 98.6%, 97.7%, and 93.3%. PSM was not associated with worse RFS in both univariable and multivariable analyses (hazard ratio [HR] = 1.43; 95% confidence interval [CI] = 0.37, 5.55; p = 0.607). Factors associated with worse RFS include pT3a upstaging (HR = 4.97; 95% CI = 1.63, 15.12; p = 0.005), a higher Charlson comorbidity index (HR = 1.68; 95% CI = 1.20, 2.34; p = 0.002); and advanced clinical stage (cT1a vs cT1b, HR = 4.22; 95% CI = 1.84, 9.68; p = 0.001 vs cT2a, HR = 14.09; 95% CI = 3.85, 51.53; p < 0.001). PSM was not associated with worse OS in both univariable and multivariable analyses (HR = 0.87; 95% CI = 0.26, 2.94; p = 0.821). Higher R.E.N.A.L. nephrometry score was found to be associated with worse OS (HR = 1.26; 95% CI = 1.01, 1.57; p = 0.041). Conclusions: Given the absence of association between PSM and worse oncologic outcomes, patients with PSM following RAPN should be carefully monitored for recurrence rather than undergo immediate secondary intervention. As advanced clinical stage (cT1b, cT2a) and pathologic upstaging (pT3a) were independently associated with disease recurrence, their presence may warrant more attentive postoperative surveillance.

A multi-institutional analysis of 263 hilar tumors during robot-assisted partial nephrectomy.

Hilar tumors pose unique challenges during partial nephrectomy. We present the characteristics and outcomes of 263 patients with hilar tumors undergoing robot-assisted partial nephrectomy (RPN) in the largest series to date. Perioperative, pathologic, functional, and oncological outcomes were compared between 1467 (84.8%) patients with a non-hilar tumor and 263 (15.2%) patients with a hilar tumor undergoing RPN. Variables were compared in univariable (unadjusted) analysis and using multivariable linear, logistic, poisson, cox proportional hazards and linear mixed effects regression models adjusting for tumor diameter and RENAL Nephrometry score. Hilar tumors were larger (3.7 vs. 3.0 cm, p < 0.001) and more complex (RENAL Score 9 vs. 7, p < 0.001), leading to longer operative time (186 vs. 161 min, p < 0.001), ischemia time (18 vs. 15, p < 0.001), greater blood loss (150 vs. 100 ml, p < 0.001), eGFR decline at discharge (∆ = 3.9%, p = 0.035) and eGFR decline per month up to 36 months post-RPN (ß = - 0.25; p = 0.017). In multivariable analysis, hilar tumors were only associated with a 10% increase in operative time (p ≤ 0.001) and marginally worse eGFR decline over time (ß = - 0.19, p = 0.076), with no differences in other outcomes analyzed including ischemia time, blood loss, complication rate, recurrence-free survival, or eGFR decline at discharge. Although hilar tumors were found to be larger and more anatomically complex, there were only marginal differences in outcome when compared to non-hilar tumors. A hilar renal tumor should be considered for partial nephrectomy when feasible without an expected increase in complications or adverse events.

Weighted Gleason Grade Group (WGGG): A new prostate cancer biopsy reporting system with prognostic potential.

INTRODUCTION: Presently, prostate biopsy (PBx) results report the highest Gleason Grade Group (GGG) as a single metric that gauges the overall clinical aggressiveness of cancer and dictates treatment. We hypothesized a PBx showing multiple cores of cancer with more volume cancer per core would represent more aggressive disease. We propose the Weighted Gleason Grade Group (WGGG), a novel scoring system that synthesizes all histopathologic data and cancer volume into a single numeric value representing the entire PBx, allowing for improved prediction of adverse pathology and risk of biochemical recurrence (BCR) following radical prostatectomy (RP). METHODS: We studied 171 men who underwent RP after standard PBx. The WGGG was calculated by summing each positive core using the formula: GGG + (GGG x %Ca/core). RP pathology was evaluated for extraprostatic extension (EPE), positive surgical margins (PSM), seminal vesicle invasion (SVI), and lymph node involvement (LNI), and patients were followed for BCR. We compared GGG vs. WGGG receiver operating characteristic curves for each outcome, and determined the predictive capability of GGG and WGGG to identify patients with BCR. Categorized WGGG groups were created based on risk of BCR using classification and regression tree analysis. We then sought to externally validate WGGG in a cohort of 389 patients in a separate institutional dataset. RESULTS: In the development cohort, area under the curves (AUCs) for the WGGG vs. GGG were significantly higher for predicting EPE (0.784 vs. 0.690, P = 0.002), SVI (AUC 0.823 vs. 0.721, P = .014), LNI (AUC 0.862 vs. 0.823, P = 0.039), and PSM (AUC 0.638 vs. 0.575, P = 0.031. Analysis of the validation cohort showed similar findings for EPE (AUC 0.764 vs. 0.729, P = 0.13), SVI (AUC 0.819 vs. 0.749, P = 0.01), LNI (AUC 0.939 vs. 0.867, P = 0.02), and PSM (AUC 0.624 vs. 0.547, P = 0.04). Patients with WGGG >30 (high-risk group) demonstrated ∼50% failure at 2 years in both cohorts. CONCLUSIONS: The WGGG, by providing a metric reflecting the entirety of the PBx, is more informative than conventional single GGG alone in identifying adverse pathologic outcomes and risk of BCR following RP. This superior discriminatory capability has been achieved without any consideration of other commonly available clinical disease characteristics.

Clinicopathologic and Genomic Factors Associated With Oncologic Outcome in Patients With Stage III to IV Chromophobe Renal Cell Carcinoma.

BACKGROUND: Chromophobe renal cell carcinoma (chRCC) is known as an indolent tumor; however, mortality still occurs. We sought to determine the clinicopathologic and genomic factors associated with aggressive chRCC. PATIENTS AND METHODS: Two different datasets were used to identify patients with clinical stage III and IV chRCC. Eighteen patients from The Cancer Genome Atlas (TCGA) database and 1693 patients from the American College of Surgeons National Cancer Database (NCDB) were used for analysis. From the TCGA, RNA-Seq expression analysis of 18,745 genes was conducted between the recurrent (n = 5; 27.8%) and nonrecurrent patients (n = 13; 72.2%). Biological significance was identified via pathway enrichment and gene function analyses. From the NCDB, Cox proportion hazards regression models were used to identify variables associated with overall survival (OS) at a median follow-up of 41.4 months. RESULTS: Between the 2 groups, 2182 genes were differentially expressed. The most commonly overexpressed pathways were neuroactive ligand-receptor interactions and cytokine-cytokine receptor interactions. The most activated gene functions were cellular, metabolic, and multicellular organismal processes. In the NCDB, multivariable analysis, age (hazard ratio [HR], 1.04; 95% confidence interval [CI], 1.03-1.05; P < .001), TNM stage IV versus III (HR, 3.86; 95% CI, 2.98-5.00; P < .001), and positive surgical margin (HR, 1.68; 95% CI, 1.45-1.96; P < .001) were associated with worse OS at a median follow-up of 41.4 months. Five-year OS was significantly lower for stage IV patients compared with stage III patients (80.0% vs. 29.9%; P < .001). CONCLUSIONS: Patients with recurrent chRCC demonstrated a differential gene expression of specific biochemical pathways. Clinical parameters associated with worse OS included age, stage, and positive surgical margin.

A Comparison of Excisional Volume Loss Calculation Methods to Predict Functional Outcome After Partial Nephrectomy.

INTRODUCTION: Functional volume loss (FVL) is a significant predictor of kidney function decline after partial nephrectomy (PN). Here, we sought to assess two different methods for quantifying FVL post-PN: imaging-based tissue segmentation (TS) vs pathological analysis. METHODS AND RESULTS: From a single surgeon series, we performed a retrospective analysis of 42 patients who underwent PN for a cT1 renal mass between 2015 and 2017. The association between TS and pathological analysis at a median follow-up of 6 months (range: 3-9 months) was evaluated using Spearman's correlation. The association between pathological analysis, TS analysis, and estimated glomerular filtration rate (eGFR) decline at 6 months was evaluated using a multivariable linear mixed-effects models. For pathological analysis, dimensions of the specimen and tumor were extracted from pathology reports. FVL was calculated as [specimen volume (Length*Width*Height*π/6) - tumor volume (Length*Width*Height* π/6)]. For TS analysis, preoperative cross-sectional imaging was used (MRI n = 20; CT n = 22). FVL was calculated as [(overall kidney volume) - (tumor volume) - (cyst volume of renal cysts >1 cm)]. Postoperative functional volume was subtracted from preoperative functional volume to assess FVL post-PN for TS method. RESULTS: eGFR significantly decreased from baseline to postoperative 6 months (-5.1 mL/min/1.73 m2; p = 0.004). Even though there was a correlation between the two methods (coefficient = 0.245, p < 0.001), pathological analysis underestimated volume loss (32.2 mL vs 5.76 mL, p < 0.001). In multivariate linear regression analysis, TS analysis was significantly associated with a decline in eGFR (ß = 0.084, 95% CI = -0.02, 0.15; p = 0.012), whereas pathological analysis was not (ß = 0.02, 95% CI = -0.24, 0.28; p = 0.87). CONCLUSION: Pathological analysis underestimates parenchymal volume loss. Only imaging-based TS method is associated with change in eGFR post-PN.

Clinicopathological and survival analysis of clinically advanced papillary and chromophobe renal cell carcinoma.

INTRODUCTION: Clinically, the papillary (pRCC) and chromophobe (chRCC) histologic subtypes of renal cell carcinoma (RCC) are viewed as more indolent compared to the more-common clear cell histology (ccRCC). However, there remain advanced cases of these purportedly less-aggressive histologies that lead to significant mortality. We therefore sought to evaluate outcomes of advanced pRCC and chRCC compared to ccRCC utilizing the National Cancer Database's registry of RCC patients. MATERIALS AND METHODS: A total of 115,365 ccRCC patients, 28,344 pRCC patients, and 11,942 chRCC patients met eligibility criteria. Overall survival (OS) was estimated using the Kaplan-Meier method (median follow-up 3.6 years). OS was compared between stage III and IV ccRCC, pRCC, and chRCC using multivariable Cox proportional hazards model adjusted for clinical and treatment characteristics. RESULTS: A total of 25.7% of ccRCC patients, 14.1% of pRCC patients, and 14.8% of chRCC patients had stage III to IV disease. The 5-year OS for stage III ccRCC, pRCC, and chRCC was 66.9%, 63.6%, and 80.5%, respectively. The 5-year OS for stage IV ccRCC, pRCC and chRCC was 19.7%, 13.3%, and 22.0%, respectively. The hazard of death was significantly higher for stage IV pRCC vs. ccRCC (hazard ratio = 1.29; 95% confidence interval = 1.19, 1.39; P < 0.01) and similar for stage IV chRCC vs. ccRCC (hazard ratio = 1.01; 95% confidence interval = 0.85, 1.21; P = 0.885). CONCLUSIONS: pRCC and chRCC are rare but similarly fatal compared to ccRCC when advanced or metastatic. With most clinical trials devoted toward ccRCC, greater efforts to identify aggressive variants and treatment strategies for metastatic pRCC and chRCC are necessary.

A Single Overnight Stay After Robotic Partial Nephrectomy Does Not Increase Complications.

Objectives: To evaluate the feasibility of postoperative day 1 (POD1) discharge after robotic partial nephrectomy (RPN) and to determine whether a protocol targeting a shorter length of stay (LOS) is associated with any difference in the rate of postoperative complications. Materials and Methods: We reviewed a prospectively maintained, multi-institutional database of patients who underwent RPN from September 2013 to September 2016. Three of the six participating surgeons used a protocol that targeted discharge on POD1, whereas three surgeons did not. Patient characteristics and postoperative complication rates between the two groups were compared. Results: A total of 665 patients were included, 455 of whom were treated by surgeons utilizing a POD1 discharge protocol, whereas 210 were not. The mean LOS for those in the POD1 protocol group was 1.13 days vs 2.02 days in the non-protocol group. Between groups, there were no differences in age (p = 0.098), body mass index (p = 0.164), tumor size (p = 0.502), or R.E.N.A.L. Nephrometry score (p = 0.974), but POD1 discharge protocol patients had higher age-adjusted Charlson comorbidity score (4 vs 2, p = 0.033), were less likely to have a hilar tumor (15.9% vs 23.1%, p = 0.03), and had a larger percent decrease in discharge estimated glomerular filtration rate (-15.9% vs -7.1%, p < 0.001). There were no differences in the rates of overall (p = 0.715), major (p = 0.164), medical (p = 0.089), or surgical complications (p = 0.301) or in complications by the Clavien-Dindo category (p = 0.13). Conclusion: Discharge on POD1 after RPN is feasible, reproducible by different surgeons, and not associated with an increased risk of postoperative complications.

Predicting acute kidney injury after robot-assisted partial nephrectomy: Implications for patient selection and postoperative management.

BACKGROUND: Acute Kidney Injury (AKI) is a common occurrence after partial nephrectomy and is a significant risk factor for chronic kidney disease. We aimed to create a model that predicts postoperative AKI in patients undergoing robot-assisted partial nephrectomy (RAPN). METHODS: We identified 1,190 patients who underwent RAPN between 2008 and 2017 from a multicenter database. AKI was defined as a >25% reduction in eGFR from pre-RAPN to discharge. A nomogram was built based on a binary logistic regression that ultimately included age, sex, BMI, diabetes, baseline eGFR, and RENAL Nephrometry score. Internal validation was performed using the leave-one-out cross validation. Calibration was graphically investigated. The decision curve analysis was used to evaluate the net clinical benefit; a classification tree was used to identify risk categories. The same model was fit adding ischemia time during RAPN. RESULTS: Median (IQR) age at surgery was 61 (50, 68) years; 505 (42%) patients were female, while 685 (58%) were male. Median (IQR) ischemia time during RAPN was 14 (10, 18) min. postoperative AKI occurred in 274 (23%) patients. All variables fitted in the model emerged as predictors of AKI (all P ≤ 0.005) and all were considered to build a nomogram. After internal validation, the area under the curve was 73%. The model demonstrated excellent calibration and improved clinical risk prediction at the decision curve analysis. In the low, intermediate, and high-risk groups the postoperative AKI rates were: 10%, 30%, and 48%, respectively. Adding ischemia time to the preoperative model fit the data better (likelihood ratio test: P < 0.001) and yielded an incremental area under the curve of 3% (95% confidence interval: 1, 5%) CONCLUSION: We developed a nomogram that accurately predicts AKI in patients undergoing RAPN. This model might serve (1) in the preoperative setting: for counsel patients according to their preoperative AKI risk (2) in the immediate postoperative: for identifying patients who would benefit from an early multidisciplinary evaluation, when considering also ischemia time.

The Impact of Obesity in Patients Undergoing Robotic Partial Nephrectomy.

Introduction: As the prevalence of obesity increases worldwide, an increasing proportion of surgical candidates have an elevated body mass index (BMI), with associated metabolic syndrome. Yet there exists limited evidence regarding the effect of elevated BMI on surgical outcomes in robotic surgeries. We examined whether obese patients had worse perioperative outcomes and postoperative renal function after robotic partial nephrectomies (RPNs). Materials and Methods: We performed a multi-institutional analysis of 1770 patients who underwent RPNs between 2008 and 2015, allowing time for the data set to mature. Associations between BMI, as a continuous and categorical variable, and perioperative outcomes, acute kidney injury (AKI, >25% reduction in estimated glomerular filtration rate [eGFR]) at discharge, and change in eGFR per month were analyzed. AKI and eGFR were evaluated using multivariable logistic and linear regression models adjusted for confounders, including age, Charlson comorbidity index, tumor size, and the identity of the surgeon. Results: In total 45.2% (n = 529) of patients were found to be obese, with a greater prevalence of hypertension and diabetes in overweight and obese patients. Obese patients were more likely to have malignant tumors (>77% vs 68%, p < 0.001) and trended toward having larger tumors (3.0 cm vs 2.8 cm; p = 0.061). Heavier patients required longer operative times (166-196 minutes vs 155 minutes; p < 0.001), although equivalent warm ischemia times (p = 0.873). Obesity did not correlate with an increased complication rate (p > 0.05). On multivariable analysis, obesity (odds ratio [OR] = 1.81; p = 0.031), male sex (OR = 1.54; p = 0.028), and larger tumor size (OR = 1.23; p < 0.001) were associated with a significant increase in the likelihood of AKI at discharge. BMI above normal weight was not associated with greater eGFR decline per month post-RPN. Conclusions: Obesity was associated with equivalent perioperative outcomes and long-term renal function. Further research is warranted into how obesity and metabolic syndrome may foster a more aggressive tumor environment. RPN appears to be an equally safe operative option for patients regardless of obesity status.

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.

A Multi-Institutional Propensity Score Matched Comparison of Transperitoneal and Retroperitoneal Partial Nephrectomy for cT1 Posterior Tumors.

OBJECTIVE: To compare the perioperative and renal functional outcome between transperitoneal and retroperitoneal robotic partial nephrectomy (TP-RPN and RP-RPN) in the largest cohort to date of RP-RPN for posterior tumors. METHODS: We identified 519 patients who met eligibility criteria and underwent TP-RPN (n = 357, 68.8%) or RP-RPN (n = 162, 31.2%) for a posteriorly located cT1 tumor. Patients were propensity score (PS) matched on preoperative and tumor-specific characteristics. Perioperative outcome and renal function outcome at median follow-up 22 months were compared. RESULTS: Between the PS matched TP-RPN (n = 157, 50%) and RP-RPN (n = 157, 50%) patients, operative time (OT) (185.0 versus 157.0, P < .001) was longer in TP-RPN versus RP-RPN patients. No significant differences in ischemia time (P = .618), blood loss (P = .178), positive surgical margins (P = .501), overall postoperative complications (P = .861), or progression of chronic kidney disease stage at median 22 months (P = .599) were identified. Length of stay (LOS) was reduced in RP-RPN patients (P = .017), but was not different once an institution used a postoperative day (POD)-1 discharge protocol (P = .579). Operative times were similar between groups in patients with obesity (P = .293) or a cT1b renal mass (P = 908). CONCLUSION: RP-RPN for posterior tumors resulted in reduced OT and a shorter LOS compared to TP-RPN. When surgeons aimed to routinely discharge patients on POD-1, the surgical approach did not influence LOS. Operative time was similar between RP and TP-RPN among patients with obesity or a cT1b renal mass. All other measures, including ischemia time, blood loss, margin rates, complications, and renal function, did not differ between the two approaches.

Management of high complexity renal masses in partial nephrectomy: A multicenter analysis.

OBJECTIVE: To determine the safety and efficacy of performing partial nephrectomy (PN) on patients with high nephrometry score tumors. PATIENTS AND METHODS: We used a prospectively maintained multi-institutional kidney cancer database to identify 144 patients with R.E.N.A.L. nephrometry score ≥10 who underwent PN for a cT1-cT2 renal mass. Baseline demographics and clinical characteristics, tumor characteristics, perioperative, and pathological outcomes were analyzed and reported. Trifecta achievement, defined by warm ischemia time <25 minutes, no perioperative complications, and negative surgical margins, was the primary outcome. We assessed the relationship of baseline clinical and tumor characteristics data to trifecta achievement and perioperative complications. RESULTS: Baseline median eGFR was 84.57 ml/min/1.73 m2, with 119 (84.39%) patients having normal baseline kidney function. The median clinical tumor size was 4.95 cm, with 74 (51.75%) being completely endophytic and 58 (41.73%) located on the hilum. The median ischemia time was 20 minutes. Median estimated blood loss was 150 ml. Twelve patients (8.33%) had intraoperative complications. No patient had a conversion to open surgery. Postoperative, perioperative, and major complication rate were 10.42%, 17.3%, and 2.34% respectively. Thirty-six patients (37.89%) developed postoperative acute kidney injury and 28 (20.90%) developed new-onset CKD at a median follow-up of 6 months. Eight patients (5.56%) had a positive surgical margin. Trifecta was achieved in 89 (61.81%) patients. There was no significant difference in baseline, clinical, and tumor characteristics between those that achieved trifecta and in those where trifecta was not. Pathologic tumor stage was the only factor significantly associated with trifecta achievement (P = 0.025). CONCLUSION: In treating complex renal tumors, PN should be performed when possible. Although this remains a challenging procedure, with experience and appropriate case selection, the trifecta outcome can be achieved in a significant number of patients with high renal score lesions.

Risk factors and prognostic implications for pathologic upstaging to T3a after partial nephrectomy.

BACKGROUND: Performing partial nephrectomy (PN) on a cT1 tumor, which postoperatively is upgraded to pT3a can possibly lead to compromise of cancer specific mortality. We therefore aimed to identify risk factors for pathologic T3a upstaging of cT1 tumors and to analyze the association between upstaging, positive surgical margins (PSM) and overall survival (OS). METHODS: The present study included patients who underwent PN for a clinically localized T1 renal mass from two datasets: 1) 1298 patients from a prospectively maintained multi-center database (MCDB); and 2) 7940 patients from the National Cancer Database (NCDB). Multivariable logistic regression models within each cohort were used to identify predictors of cT1 to pT3a upstaging and its association with PSM. Cox proportion hazards regression models were used to compare overall survival in the NCDB cohort. RESULTS: The rate of pT3a upstaging was 5.7% (N.=74) in the MCDB and 1.9% (N.=156) in the NCDB cohort. Older age (MCDB OR=1.04, P=0.001; NCDB OR=1.04, P=0.001) and larger tumor size (MCDB OR=1.89, P<0.001; NCDB OR=1.38, P<0.001) increased the likelihood of upstaging. PSM was found to be more likely for pT3a upstaged patients in both cohorts (MCDB 14.9% vs. 3.5%, P<0.001; NCDB 14.8% vs. 8.3%, P=0.006), even when adjusting for tumor size. At short term follow-up (NCDB median follow-up 27.3 months), pT3a upstaging was associated with worse OS in univariable (HR=1.89; 95% CI=1.00, 3.55; P=0.049) but not multivariable analysis (HR=1.63; 95% CI=0.86, 3.08; P=0.131). OS was 93.0% vs. 95.8% at 3 years for those with and without pT3a upstaging, respectively. CONCLUSIONS: Larger tumor size and increased age are associated with pathological upstaging to T3a for clinical T1 tumors treated with partial nephrectomy. Steps to improve identification of occult pT3a disease are necessary as its occurrence significantly increased the likelihood of a PSM, both in a high-volume multicenter cohort, as well as, a national data registry.