Contemporary Diagnosis of Very Low-risk Prostate Cancer in a Multihospital Health Care System.

The National Comprehensive Cancer Network (NCCN) very low risk (VLR) category for prostate cancer (PCa) represents clinically insignificant disease, and detection of VLR PCa contributes to overdiagnosis. Greater use of magnetic resonance imaging (MRI) and biomarkers before patient selection for prostate biopsy (PBx) reduces unnecessary biopsies and may reduce the diagnosis of clinically insignificant PCa. We tested a hypothesis that the proportion of VLR diagnoses has decreased with greater use of MRI-informed PBx using data from our 11-hospital system. From 2018 to 2023, 351/3197 (11%) men diagnosed with PCa met the NCCN VLR criteria. The proportion of VLR diagnoses did not change from 2018 to 2023 (p = 0.8) despite an increase in the use of MRI-informed PBx (from 49% to 82%; p < 0.001). Of patients who underwent combined systematic and targeted PBx and were diagnosed with VLR disease, cancer was found in systematic PBx regions in 79% of cases and in targeted PBx regions in 31% of cases. When performing both systematic and targeted PBx, prebiopsy MRI-based risk calculators could limit VLR diagnosis by 41% using a risk threshold of >5% for Gleason grade group ≥3 PCa to recommend biopsy; the reduction would be 77% if performing targeted PBx only. These findings suggest that VLR disease continues to account for a significant minority of PCa diagnoses and could be limited by targeted PBx and risk stratification calculators. PATIENT SUMMARY: We looked at recent trends for the diagnosis of very low-risk (VLR) prostate cancer. We found that VLR cancer still seems to be frequently diagnosed despite the use of MRI (magnetic resonance imaging) scans before biopsy. The use of risk calculators to identify men who could avoid biopsy and/or biopsy only for lesions that are visible on MRI could reduce the overdiagnosis of VLR prostate cancer.

Fully Automated Versions of Clinically Validated Nephrometry Scores Demonstrate Superior Predictive Utility versus Human Scores.

OBJECTIVE: To automate the generation of three validated nephrometry scoring systems on preoperative computerised tomography (CT) scans by developing artificial intelligence (AI)-based image processing methods. Subsequently, we aimed to evaluate the ability of these scores to predict meaningful pathological and perioperative outcomes. PATIENTS AND METHODS: A total of 300 patients with preoperative CT with early arterial contrast phase were identified from a cohort of 544 consecutive patients undergoing surgical extirpation for suspected renal cancer. A deep neural network approach was used to automatically segment kidneys and tumours, and then geometric algorithms were used to measure the components of the concordance index (C-Index), Preoperative Aspects and Dimensions Used for an Anatomical classification of renal tumours (PADUA), and tumour contact surface area (CSA) nephrometry scores. Human scores were independently calculated by medical personnel blinded to the AI scores. AI and human score agreement was assessed using linear regression and predictive abilities for meaningful outcomes were assessed using logistic regression and receiver operating characteristic curve analyses. RESULTS: The median (interquartile range) age was 60 (51-68) years, and 40% were female. The median tumour size was 4.2 cm and 91.3% had malignant tumours. In all, 27% of the tumours were high stage, 37% high grade, and 63% of the patients underwent partial nephrectomy. There was significant agreement between human and AI scores on linear regression analyses (R ranged from 0.574 to 0.828, all P < 0.001). The AI-generated scores were equivalent or superior to human-generated scores for all examined outcomes including high-grade histology, high-stage tumour, indolent tumour, pathological tumour necrosis, and radical nephrectomy (vs partial nephrectomy) surgical approach. CONCLUSIONS: Fully automated AI-generated C-Index, PADUA, and tumour CSA nephrometry scores are similar to human-generated scores and predict a wide variety of meaningful outcomes. Once validated, our results suggest that AI-generated nephrometry scores could be delivered automatically from a preoperative CT scan to a clinician and patient at the point of care to aid in decision making.

Survival benefits after radical nephrectomy and IVC thrombectomy of renal cell carcinoma patients with inferior vena cava thrombus.

Objective: The role of tumor thrombus as a predictor of survival in patients with renal cell carcinoma (RCC) is controversial. This study aims to evaluate surgical and oncological outcomes after surgery in RCC with inferior vena cava (IVC) tumor thrombus patients. Materials and methods: A total of 58 patients (2002-2019) underwent radical nephrectomy and IVC thrombectomy at our institute, were retrospectively reviewed. Kaplan-Meier analysis was utilized to compare survival benefits between cohorts and Cox-regression to evaluate potential predictors of patient survival. Results: There were 5(8.6%), 21(36.2%), 23(39.7%) and 9 (15.5%) patients with tumor thrombus level I, II, III and IV respectively. The major complications (Clavien 3-5) were observed in 15 patients (25.8%) and 12 patients (80%) were patients with high thrombus level (III-IV). There was 9%mortality (5patients): 2 intraoperatively and 3 postoperatively. Median follow-up was 15 months (IQR:5-41). Two-year overall survival (OS) was 80% and 75% in all patients and pN0M0 cohort, respectively. There was significant difference in OS among each IVC thrombus level cohort (p < 0.02). Two-year OS of metastatic RCC patients was 67% and not significantly different when compared to non-metastatic cohort (p = 0.12). On multivariate analysis, only sarcomatoid dedifferentiation was associated with OS(p = 0.04). Disease-free survival was not significantly different among thrombus-level cohorts (p = 0.65). Conclusions: Our study suggested that surgical treatment for RCC with IVC thrombus provided substantial OS outcomes. Although survival was significantly reduced with higher IVC thrombus level cohort, the level of thrombus itself was not an independent factor. Only sarcomatoid dedifferentiation was a predictor for reduced OS after radical nephrectomy and tumor thrombectomy. Meticulous patient selection and prompt counselling are substantial step for the operation.

A clinical overview of people living with HIV and genitourinary cancer care.

The number of people living with HIV infection has been increasing globally. Administration of antiretroviral therapy is effective in controlling the infection for most patients and, as a consequence, people living with HIV (PLWH) now often have a long life expectancy. However, their risk of developing cancer - most notably virus-related cancers - has been increasing. To date, few studies have assessed the risk of genitourinary cancers in PLWH, and robust scientific data on their treatment-related outcomes are lacking. Previous studies have noted that PLWH are at a reduced risk of prostate cancer; however, low adoption and/or availability of prostate cancer screening among these patients might be confounding the validity of this finding. In genitourinary cancers, advanced stage at diagnosis and reduced cancer-specific mortality have been reported in PLWH. These data likely reflect, at least in part, the inequity of health care access for PLWH. Notably, systemic chemotherapy and/or radiotherapy could decrease total CD4+ cell counts, which could, therefore, increase the risk of morbidity and mortality from cancer treatments in PLWH. Immune checkpoint inhibitors have become the therapeutic backbone for many advanced malignancies in the general population; however, most studies validating their efficacy have excluded PLWH owing to concerns of severe adverse effects from immune checkpoint inhibitors themselves and/or related to their immunosuppressed status. To our knowledge, no genitourinary cancer survivorship programme exists that specifically caters to the needs of PLWH. By including PLWH in ongoing cancer trials, we can gain invaluable insights that will help to improve cancer care specifically for PLWH.

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.

Parenchymal Volume Replacement by Renal Cell Carcinoma Prior to Intervention: Predictive Factors and Functional Implications.

OBJECTIVE: To analyze predictors, extent and functional implications associated with renal parenchymal volume replacement (PVR) by renal cell carcinoma (RCC) prior to intervention. This phenomenon is well-recognized yet not adequately studied, and, if severe, can influence management. MATERIALS AND METHODS: A retrospective review was performed of partial nephrectomy (PN) and radical nephrectomy (RN) patients with available preoperative nuclear-renal-scan and imaging demonstrating solitary RCC with normal contralateral kidney. Normal renal parenchymal volume of each kidney was measured by free-hand scripting from preoperative axial images. Primary endpoint was percent PVR which was estimated assuming that the contralateral-kidney serves as a control: PVR = (volume contralateral kidney - volume ipsilateral kidney) normalized by volume contralateral kidney. Multivariable linear-regression analysis assessed factors associated with preoperative PVR. Further analysis evaluated the functional effect of PVR prior to surgery. RESULTS: 146 PN and 136 RN patients with necessary studies were analyzed. For RN, the median PVR was 15% and a quarter of patients had PVR ≥27%. In contrast, PVR was negligible in PN patients for whom median preoperative parenchymal volumes were nearly identical in the ipsilateral/contralateral kidneys (179/180cc, respectively). PVR inversely correlated with preoperative renal function in the ipsilateral kidney (P <.01). Tumor-size (P <.01), stage (P = .03), and endophytic properties (P = .03) associated with PVR on multivariable-analysis. CONCLUSION: Our data suggest that substantial replacement of normal parenchyma by RCC occurs in many patients selected for RN and can contribute to preexisting renal-insufficiency. PVR prior to intervention is mainly driven by tumor characteristics in RN patients, but is negligible in most PN patients.

The current role of cytoreductive nephrectomy for metastatic renal cell carcinoma.

The management of metastatic renal cell carcinoma (mRCC) continues to be a therapeutic challenge; however, the options for systemic therapy in this setting have exploded over the past 20 years. From the advent of toxic cytokine therapy to the subsequent discovery of targeted therapy (TT) and immune checkpoint inhibitors, the landscape of viable treatment options continues to progress. With the arrival of cytokine therapy, two randomized trials demonstrated a survival benefit for upfront cytoreductive nephrectomy (CN) plus interferon therapy and this approach became the standard for surgical candidates. However, it was difficult to establish the role and the timing of CN with the subsequent advent of TT, just a few years later. More recently, two randomized phase III studies completed in the TT era questioned the use of CN and brought to light the role of risk stratification while selecting patients for CN. Careful identification of the mRCC patients who are likely to have a rapid progression of the disease is essential, as these patients need prompt systemic therapy. With the continued advancement of systemic therapy using the immune checkpoint inhibitors as a first line therapy, the role of CN will continue to evolve.

Infiltrative Renal Masses: Clinical Significance and Fidelity of Documentation.

BACKGROUND: The prevalence of infiltrative renal masses (IRMs) and fidelity of documentation of infiltrative features remain unclear. OBJECTIVE: To investigate the prevalence/significance of IRMs and assess whether infiltrative features were documented preoperatively. DESIGN, SETTING, AND PARTICIPANTS: A total of 522 patients with renal tumors managed with partial/radical nephrectomy (2012-2014) whose pathology demonstrated locally advanced and/or aggressive histology were analyzed. Preoperative computed tomography/magnetic resonance imaging was retrospectively/independently reviewed by two radiologists. IRMs were required to have a poorly defined interface with parenchyma and nonelliptical shape in one or more distinct/unequivocal areas. Infiltrative features were defined as extensive or focal. INTERVENTION: Partial/radical nephrectomy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Cancer-specific mortality (CSM) was estimated using cumulative-incidence analysis. Significant and independent predictors of CSM were evaluated using Cox proportional hazard analysis. RESULTS AND LIMITATIONS: Median tumor size was 6.9cm; renal cell carcinomas (RCCs) predominated (92%). Image review confirmed 133 IRMs (25%), including 103 RCCs; 59 had sarcomatoid or poorly differentiated features. IRMs were larger and more often symptomatic compared than non-IRMs, and disseminated disease was also more common for IRMs (all p<0.001). Overall, 109 IRMs were imaged at our center; 42 were documented as IRMs in preoperative radiology reports, while infiltrative features were not documented in 67 (61%). Only four (6%) of these 67 were documented as infiltrative by the surgical team. Infiltrative features were more often focal in undocumented IRMs. On multivariable analysis, infiltrative features, disseminated disease, and non-RCC histology were independent predictors of CSM (hazard ratio or HR [95% confidence interval {CI}]=1.73 [1.21-2.47], 2.98 [2.10-4.23], and 2.79 [1.86-4.62], respectively). Among IRMs, extensive infiltrative features and disseminated disease were associated with CSM (HR [95% CI]=1.98 [1.27-3.07] and 2.35 [1.52-3.63], respectively), while documentation status failed to show an association. Excluding patients with disseminated disease or residual cancer after surgery, recurrence rates were 62% for IRMs versus 22% for non-IRMs (p<0.001), and there was again no significant difference between documented and undocumented IRMs (p=0.36). Limitations include a retrospective design. CONCLUSIONS: Twenty-five percent of locally advanced/histologically aggressive renal tumors exhibited infiltrative features, although many were not documented as IRMs. Among this high-risk surgical population, infiltrative features were independent predictors of CSM, irrespective of whether they were documented or not. Our data suggest that infiltrative features should be assessed and documented routinely during evaluation of renal masses. PATIENT SUMMARY: Infiltrative renal masses may be more common than previously appreciated, although many were not documented as infiltrative during preoperative evaluation. Our data suggest that infiltrative features have a strong impact on prognosis and should be assessed and documented routinely during radiologic and clinical evaluation of renal masses.

Intraoperative and early postoperative complications in postchemotherapy retroperitoneal lymphadenectomy among patients with germ cell tumors using validated grading classifications.

BACKGROUND: Postchemotherapy retroperitoneal lymphadenectomy (PC-RPLND) is an essential, yet potentially morbid, therapy for the management of patients with advanced germ cell tumors. In the current study, the authors sought to define the complication profile of PC-RPLND using validated grading systems for intraoperative adverse events (iAEs) and early postoperative complications. METHODS: Between 2000 and 2018, all patients who underwent PC-RPLND were analyzed for iAEs and early postoperative complications using the Kaafarani and Clavien-Dindo classifications, respectively. Logistic regression models were conducted to assess patient and tumor factors associated with iAEs and postoperative complications. RESULTS: Of the 453 patients identified, 115 patients (25%) and 252 patients (56%), respectively, experienced an iAE and postoperative complication. Major iAEs (grade ≥3) were observed in 15 patients (3%) and major postoperative complications (grade ≥3) were noted in 80 patients (18%). The most common iAE was vascular injury (112 of 132 events; 85%), which occurred in 92 patients (20%), and the most frequent postoperative complication was ileus, which occurred in 121 patients (27%). Original and postchemotherapy retroperitoneal mass size, nonretroperitoneal metastases, intermediate and/or poor International Germ Cell Cancer Collaborative Group classification, previous RPLND, elevated tumor markers at the time of RPLND, and anticipated adjuvant surgical procedures increased the risk of both iAEs and postoperative complications. Patients who experienced an iAE were significantly more likely to experience a postoperative complication (odds ratio, 2.50; 95% confidence interval, 1.58-3.97 [P < .001]). CONCLUSIONS: In what to the authors' knowledge is the first analysis of PC-RPLND using validated classifications for both iAEs and postoperative complications, advanced disease and surgical complexity significantly increased the risks of major iAEs and postoperative complications. Standardized reporting of adverse perioperative events allows providers and patients to appreciate the consequences of PC-RPLND during counseling and decision making.

Compensatory Changes in Parenchymal Mass and Function after Radical Nephrectomy.

PURPOSE: Loss of renal function remains a major limitation of radical nephrectomy. The extent of renal functional compensation by the preserved kidney after radical nephrectomy has not been adequately studied in this elderly population with comorbidities. MATERIALS AND METHODS: A total of 273 patients treated with radical nephrectomy without end stage renal disease with available preoperative nuclear renal scans were included in the analysis. Renal functional compensation was defined as percent change in estimated glomerular filtration rate of the preserved kidney after radical nephrectomy. Estimated glomerular filtration rate was calculated by the Chronic Kidney Disease-Epidemiology Collaboration formula up to 5 years postoperatively. Preoperative/postoperative parenchymal volumes of the preserved kidney were measured from cross-sectional imaging. Multiple regression was used to identify predictive factors for renal functional compensation. RESULTS: Median age was 67 years and 67% of the patients were male. Overall 70% had hypertension, 26% diabetes and 37% preexisting chronic kidney disease. Locally advanced (T3a or greater) tumors were found in 53% of cases. Renal functional compensation was observed at 2 weeks (median 10%) and increased during the first 3 months (median 26%) after radical nephrectomy. Functional stability was then observed to 5 years. Renal parenchymal volume increased a median of 10% at 3 to 12 months but in addition, the functional efficiency per unit of parenchymal volume also increased 8% (estimated glomerular filtration rate units/cm3 of parenchyma was 0.236 postoperatively vs 0.208 preoperatively, p=0.004). Age (-0.85, p <0.01), global preoperative estimated glomerular filtration rate (-0.28, p <0.01) and split renal function of the removed kidney (0.61, p <0.01) were independent predictors of renal functional compensation. CONCLUSIONS: Percent renal functional compensation after radical nephrectomy is greater in younger patients, when preoperative estimated glomerular filtration rate is lower and when the removed kidney has more robust function. Increases in measurable parenchymal mass and functional efficiency contribute substantially to renal functional compensation.

The Complete Spectrum of Infiltrative Renal Masses: Clinical Characteristics and Prognostic Implications.

OBJECTIVE: To analyze the full spectrum of patients presenting with radiologically-identified infiltrative renal masses (IRMs), including those managed surgically or otherwise, with focus on clinical presentation/prognosis. METHODS: All 280 patients presenting with radiologically-identified renal mass with infiltrative features (2008-2017) were retrospectively reviewed. Poorly-defined interface between tumor and parenchyma and irregular shape (nonelliptical) in one or more distinct/unequivocal areas were required for classification as IRM. IRM was confirmed in 265 and clinical characteristics and outcomes were assessed. RESULTS: Median age/tumor size were 65-years/6.9 cm, respectively, and 225 patients (85%) were R.E.N.A.L. = 10-12. Overall, 181 patients (68%) presented symptomatically, locally-advanced cancer (cT3-T4) was observed in 176 (66%) and disseminated disease and/or lymphadenopathy (>2 cm) in 181(68%). Clinical/radiographic findings were suggestive of etiology and could direct evaluation, but were nonspecific for definitive diagnosis. Renal-mass biopsy was performed in 103 patients and diagnostic in 97 (94%). Renal surgery was only performed in 82 patients (31%) and partial nephrectomy in 3 (1.1%). Overall, 72 patients (27%) received systemic chemotherapy and 59 (22%) targeted therapy. Final-diagnosis was renal cell carcinoma in 94 patients (35%), including 49 with highly-aggressive histology (sarcomatoid/rhabdoid/collecting-duct/medullary/unclassified). High-grade urothelial-carcinoma was found in 70 (26%), and lymphoma/metastatic cancer in 26 (10%)/25 (9%), respectively. Overall, 153 patients (58%) died; 138 (52%) cancer-related at median of 5 months. The majority of patients with renal cell carcinoma, urothelial-carcinoma, and renal metastasis died, almost exclusively cancer-related, at medians of 8, 3, and 2 months, respectively. CONCLUSION: Our series includes the full spectrum of IRMs and confirms predominance of symptomatic, poorly-differentiated, highly-lethal malignancies. Our study highlights the overriding importance of identifying infiltrative features, a simple radiologic diagnosis, during assessment of renal masses.

Vascularized Parenchymal Mass Preserved with Partial Nephrectomy: Functional Impact and Predictive Factors.

BACKGROUND: Percentage parenchymal mass preserved (PPMP) is a key determinant of functional outcomes after partial nephrectomy (PN); however, predictors of PPMP have not been defined. OBJECTIVE: To provide a comprehensive analysis of the functional impact of and potential predictive factors for PPMP. DESIGN, SETTING, AND PARTICIPANTS: We analyzed data for 464 patients managed with PN at our center with necessary studies to determine vascularized parenchymal mass and function preserved within the operated kidney. PPMP was measured from computed tomography scans <2 mo before and 3-12 mo after PN. INTERVENTION: PN. OUTCOME MEASUREMENTS/STATISTICAL ANALYSIS: Recovery from ischemia was defined as percentage ipsilateral glomerular filtration rate (GFR) preserved normalized by PPMP. We used Pearson correlation to evaluate the relationships between GFR preserved and PPMP. Multivariable logistic regression was used to assess predictors of PPMP. RESULT AND LIMITATIONS: Ninety-six patients (21%) had a solitary kidney. The median tumor size and RENAL score were 3.5cm and 8, respectively. Cold/warm ischemia were utilized in 183/281 patients for which the median ischemia time were 28/20min. The median preoperative and postoperative vascularized parenchymal mass in the operated kidney were 194 and 157cm3, respectively, resulting in median PPMP of 84%. GFR preservation correlated strongly with PPMP (r=0.64; p<0.001). Recovery from ischemia was suboptimal (<80%) in 71 patients (15%), while suboptimal PPMP (<80%) was a more common adverse event, occurring in 160 patients (34%; p<0.001). Multivariable analysis demonstrated that greater tumor size and complexity were associated with lower PPMP (p≤0.04), while solitary kidney and hypothermia were associated with higher PPMP (p<0.001). Longer ischemia time was also associated with lower PPMP (p=0.003), probably reflecting the complexity of the surgery. Limitations include the retrospective design. CONCLUSION: PPMP correlates strongly with functional outcomes after PN, and lower PPMP is the most common and important source of functional decline after PN. Larger tumors, greater tumor complexity, and prolonged ischemia time were associated with lower PPMP, while PPMP tended to be greater for solitary kidneys, confirming that PPMP is a modifiable factor. PATIENT SUMMARY: Kidney function after partial nephrectomy primarily depends on the amount of vascularized kidney preserved by the procedure. Lower recovery of function is seen when operating on larger tumors in unfavorable locations, but preservation of the parenchymal mass can be improved when truly necessary, such as when operating on a tumor in a solitary kidney.

Renal Cancer Surgery in Patients without Preexisting Chronic Kidney Disease-Is There a Survival Benefit for Partial Nephrectomy?

PURPOSE: Retrospective studies suggest that partial nephrectomy provides improved survival compared to radical nephrectomy even when performed electively. However, selection bias may contribute. We evaluated factors associated with nonrenal cancer related mortality after partial and radical nephrectomy in patients with a preoperative glomerular filtration rate of 60 ml/minute/1.73 m2 or greater. MATERIALS AND METHODS: We retrospectively evaluated the records of 3,133 patients with a preoperative glomerular filtration rate of 60 ml/minute/1.73 m2 or greater who underwent partial or radical nephrectomy. Nonrenal cancer related mortality was analyzed by the Kaplan-Meier test based on procedure and functional parameters, including the new baseline glomerular filtration rate. We used the Cox proportional hazards model to assess factors associated with nonrenal cancer related mortality among patients with a new baseline rate of 45 ml/minute/1.73 m2 or greater. RESULTS: Overall median age was 59 years and the median preoperative glomerular filtration rate was 85 ml/minute/1.73 m2. The new baseline glomerular filtration rate was 80 and 63 ml/minute/1.73 m2 and 10-year nonrenal cancer related mortality was 11.3% and 17.7% after partial and radical nephrectomy, respectively (each p <0.001). Median followup was 9.3 years. Nonrenal cancer related mortality was similar in all patients with a new baseline glomerular filtration rate of 45 ml/minute/1.73 m2 or greater (p = 0.26). However, it increased 50% or more in the 290 patients with a new baseline below this level (p = 0.001). In patients with a new baseline greater than 45 ml/minute/1.73 m2 10-year nonrenal cancer related mortality was still substantially improved after partial nephrectomy (10.6% vs 16.3%, p <0.001). In this population age, gender and partial vs radical nephrectomy were associated with nonrenal cancer related mortality on multivariable analysis (all p ≤0.001). In contrast, the increased new baseline glomerular filtration rate, as seen for partial nephrectomy, was not associated with reduced nonrenal cancer related mortality. CONCLUSIONS: In patients with a glomerular filtration rate of 60 ml/minute/1.73 m2 or greater who undergo partial or radical nephrectomy our data suggest that treatment should achieve a new baseline of 45 ml/minute/1.73 m2 or greater if feasible. Partial nephrectomy should be prioritized if needed to accomplish this. In patients with a new baseline rate of 45 ml/minute/1.73 m2 or greater partial nephrectomy was associated with improved survival. However, the functional dividend, namely the increased new baseline rate, failed to correlate, suggesting that selection bias may also impact outcomes.

Can We Predict Functional Outcomes after Partial Nephrectomy?

PURPOSE: The percent of preserved parenchymal mass is the primary determinant of functional outcomes after partial nephrectomy. Accurate methods to predict the percent of preserved parenchymal mass based on preoperative imaging could facilitate patient counseling. MATERIALS AND METHODS: We evaluated the records of 428 patients who had undergone partial nephrectomy and the studies necessary to assess preserved ipsilateral parenchymal mass and function. Preoperative and postoperative ipsilateral parenchymal volumes were measured from contrast enhanced computerized tomography less than 2 months before and 3 to 12 months after partial nephrectomy and the actual percent of preserved parenchymal mass was determined. The ipsilateral percent of preserved parenchymal mass and the final global glomerular filtration rate were estimated based on preoperative imaging using subjective estimation, quantitative estimation, or estimation derived from the contact surface area or the R.E.N.A.L. (radius, exophytic/endophytic, nearness of tumor to collecting system or sinus, anterior/posterior and location relative to polar lines) score. RESULTS: Median tumor diameter was 3.5 cm, median contact surface area was 24 cm2 and the median R.E.N.A.L. score was 8. The median actual ipsilateral percent of preserved parenchymal mass was 84% and the preserved percent of the global glomerular filtration rate was 89%. The median estimated ipsilateral percent of preserved parenchymal mass was 85%, 87%, 88% and 83% based on subjective estimation, quantitative estimation, contact surface area and the R.E.N.A.L. score, respectively. Correlations between the actual and the estimated percent of preserved parenchymal mass were relatively weak in all instances (all r ≤0.46). Prediction of the final global glomerular filtration rate was strong for all 4 methods (all r = 0.91). However, a similarly strong correlation was obtained when presuming that 89% of the preoperative global glomerular filtration rate would be saved in each case (r = 0.91). On multivariable analyses a solitary kidney, the preoperative glomerular filtration rate and various estimates of the percent of preserved parenchymal mass were significantly associated with the final global glomerular filtration rate. However, the preoperative glomerular filtration rate proved to be the strongest predictor. It had more than a tenfold impact compared to the estimated percent of preserved parenchymal mass or a solitary kidney. CONCLUSIONS: Currently available methods to estimate the percent of preserved parenchymal mass have important limitations. The final global glomerular filtration rate, which is the most important functional outcome, could be predicted fairly accurately by all tested methods. However, none of them were better than simply presuming that 89% of function would be saved due to strong anchoring to the preoperative glomerular filtration rate.

Open partial nephrectomy when a non-flank approach is required: indications and outcomes.

PURPOSE: To evaluate indications/outcomes for open partial nephrectomy (OPN) when non-flank approaches are required, with comparison to patients managed with the flank approach. Outcomes with a non-flank approach are presumed less favorable yet there have been no previous reports on this topic. METHODS: 2747 OPNs were performed (1999-2015) and 76 (2.8%) required a non-flank approach. We also reviewed all traditional flank OPNs performed during odd years in this timeframe yielding 1467 patients for comparison. RESULTS: Overall, median tumor size was 3.5 cm and 274 patients (18%) had a solitary kidney. Non-flank patients were younger, and tumor size and clinical/pathologic stage were significantly increased for this cohort, but the groups were otherwise comparable. Indications for non-flank OPN included large tumor size/locally advanced disease (n = 21), need for simultaneous surgery (n = 25), previous flank incision or failed thermoablation (n = 13), or congenital/vascular abnormalities (n = 9). The most common non-flank approach was anterior subcostal (n = 39, 51%). Operative times, estimated blood loss, positive margins, and functional decline were all modestly increased for non-flank patients. Intraoperative and genitourinary complications were more common in non-flank patients (p < 0.05), although all were manageable, typically with conservative measures. There were no mortalities among non-flank patients and none required long-term dialysis. CONCLUSIONS: Our series, the first to address this topic, suggests that outcomes with non-flank OPN are generally less advantageous likely reflecting increased tumor/operative complexity. However, complications in this challenging patient population are manageable and final dispositions are generally favorable. Our findings should be useful for counseling regarding potential outcomes when a non-flank incision is required.

Acute Kidney Injury after Partial Nephrectomy of Solitary Kidneys: Impact on Long-Term Stability of Renal Function.

PURPOSE: Acute kidney injury often leads to chronic kidney disease in the general population. The long-term functional impact of acute kidney injury observed after partial nephrectomy has not been adequately studied. MATERIALS AND METHODS: From 2004 to 2014 necessary studies for analysis were available for 90 solitary kidneys managed by partial nephrectomy. Functional data at 4 time points included preoperative serum creatinine, peak postoperative serum creatinine, new baseline serum creatinine 3 to 12 months postoperatively and long-term followup serum creatinine more than 12 months postoperatively. Adjusted acute kidney injury was defined by the ratio, observed peak postoperative serum creatinine/projected postoperative serum creatinine adjusted for parenchymal mass loss to reveal the true effect of ischemia. The long-term change in renal function (the long-term functional change ratio) was defined as the most recent glomerular filtration rate/the new baseline glomerular filtration rate. The relationship between the grade of the adjusted acute kidney injury and the long-term functional change was assessed by Spearman correlation analysis and multivariable regression. RESULTS: Median patient age was 64 years and median followup was 45 months. Median parenchymal mass preservation was 80%. Adjusted acute kidney injury occurred in 42% of patients, including grade 1 injury in 20 (22%) and grade 2/3 in 18 (20%). On univariable analysis the degree of the adjusted acute kidney injury did not correlate with the long-term glomerular filtration rate change (p = 0.55). On multivariable analysis adjusted acute kidney injury was not associated with a long-term functional change (p >0.05) while diabetes and warm ischemia were modestly associated with a long-term functional decline (each p <0.05). CONCLUSIONS: Acute kidney injury after partial nephrectomy was not a significant or independent predictor of long-term functional decline in our institutional cohort. A prospective study with larger sample sizes and longer followup is required to evaluate factors associated with long-term nephron stability.

Tumor Contact Surface Area As a Predictor of Functional Outcomes After Standard Partial Nephrectomy: Utility and Limitations.

OBJECTIVE: To evaluate contact surface area (CSA) between the tumor and parenchyma as a predictor of ipsilateral parenchyma and function preserved after partial nephrectomy (PN). Previous studies suggested that CSA is a strong predictor of functional outcomes but the limitations of CSA have not been adequately explored. PATIENTS AND METHODS: Four hundred nineteen patients managed with standard PN for solitary tumor with necessary studies to evaluate and analyze ipsilateral preoperative or postoperative parenchymal mass and function. Parenchymal mass and CSA were measured using contrast-enhanced computed tomography <2 months prior and 3-12months after PN. CSA was calculated: 2πrd, where r = radius and d = intraparenchymal depth. Pearson-correlation evaluated relationships between CSA and ipsilateral parenchymal mass or function preserved. Multivariable regression assessed predictors of function preserved. Conceptually, the CSA paradigm should function better for exophytic tumors than endophytic ones. RESULTS: Median tumor size was 3.5 cm and R.E.N.A.L. was 8. Median global and ipsilateral glomerular filtration rate preserved were 89% and 79%, respectively. Median ipsilateral parenchymal mass preserved was 85% and significantly higher for exophytic masses (P = .001). Median CSA was 22.8 cm2 and significantly less for exophytic masses (P = .02). CSA associated with both ipsilateral function and mass preserved (both P < .05), but the correlations were only modest (r = 0.25 and 0.36, respectively). On multivariable analysis, CSA associated with function preserved for exophytic masses (P = .01), but not for endophytic ones (P = .27). CONCLUSION: CSA associates with functional outcomes after standard PN, although the strength of the correlations was modest, unlike previous studies, and CSA was not an independent predictor for endophytic tumors. Further study will be required to evaluate the utility of CSA in various clinical settings.

The Impact of Arterial Clamping Technique in Robot-Assisted Partial Nephrectomy on Renal Function and Surgical Outcomes: Six-Year Experience at Siriraj Hospital, Thailand.

INTRODUCTION: Robot-assisted partial nephrectomy (RAPN) with different arterial clamping techniques has increasingly been performed to avoid ischemic injury to nephron. However, postoperative renal function remains controversial. We determine the impact of each renal arterial clamping on surgical and renal outcomes after RAPN. MATERIALS AND METHODS: Patients who underwent RAPN at Siriraj Hospital from 2010 to 2016 were retrospectively reviewed and stratified into 3 cohorts: main-clamp (MAC), selective-clamp, and off-clamp. RESULTS: Main, selective, and off-clamping were performed in 27, 38, and 12, respectively. Median tumor size and Radius, Exophytic or endophytic, Nearness to collecting system or sinus, Anterior or posterior, and Location relative to polar lines (RENAL) score were 3 cm and 7, respectively. Longer operative time was observed in MAC (p = 0.002) although estimated blood loss, transfusion rate, and complication were comparable. Warm ischemia time was not different between cohorts. However, number of patients with prolonged ischemia time in MAC were greater (p ≤ 0.01). All margins were negative. Median postoperative and latest glomerular filtration rate reduction were 3.8 and 5.3 mL/min/1.73 m2, respectively without significant difference between cohorts. On multivariable analysis, hypertension independently associated with reduced renal function preserved (p = 0.03). Median follow-up was 18 months. CONCLUSIONS: Our study is the first to report surgical and renal functional outcomes after RAPN in Southeast-Asian population. Based on our experience, clamping techniques does not impact on renal functions and complication rate was low even in small-volume center.