Incident CKD after Radical or Partial Nephrectomy

Renal and major clinical outcomes and their determinants after nephrectomy in patients with pre-existing chronic kidney disease: A retrospective cohort study

The consequences of partial nephrectomy (PN) compared to radical nephrectomy (RN) are less documented in patients with pre-existing chronic kidney disease (CKD) or with solitary kidney (SK). We assessed renal outcomes, and their determinants, after PN or RN in a retrospective cohort of patients with moderate-to-severe CKD (RN-CKD and PN-CKD) or SK (PN-SK). All surgical procedures conducted between 2013 and 2018 in our institution in patients with pre-operative estimated glomerular filtration rate (eGFR)<60 mL/min/1.73m2 or with SK were included. The primary outcome was a composite criterion including CKD progression or major adverse cardio-vascular events (MACE) or death, assessed one year after surgery. Predictors of the primary outcome were determined using multivariate analyses. A total of 173 procedures were included (67 RN, and 106 PN including 27 SK patients). Patients undergoing RN were older, with larger tumors. Preoperative eGFR was not significantly different between the groups. One year after surgery, PN-CKD was associated with lower rate of the primary outcome compared to RN-CKD (43% vs 71% p = 0.007). In multivariate analysis, independent risk factors for the primary outcome were postoperative AKI (stage 1 to stage 3 ranging from OR = 8.68, 95% CI 3.23-23.33, to OR = 28.87, 95% CI 4.77-167.61), larger tumor size (OR = 1.21 per cm, 95% CI 1.02-1.45), while preoperative eGFR, age, sex, diabetes mellitus, and hypertension were not. Postoperative AKI after PN or RN was the major independent determinant of worse outcomes (CKD progression, MACE, or death) one year after surgery.

Stereotactic ablative body radiotherapy for primary kidney cancer (TROG 15.03 FASTRACK II): a non-randomised phase 2 trial

BACKGROUND

Stereotactic ablative body radiotherapy (SABR) is a novel non-invasive alternative for patients with primary renal cell cancer who do not undergo surgical resection. The FASTRACK II clinical trial investigated the efficacy of SABR for primary renal cell cancer in a phase 2 trial.

METHODS

This international, non-randomised, phase 2 study was conducted in seven centres in Australia and one centre in the Netherlands. Eligible patients aged 18 years or older had biopsy-confirmed diagnosis of primary renal cell cancer, with only a single lesion; were medically inoperable, were at high risk of complications from surgery, or declined surgery; and had an Eastern Cooperative Oncology Group performance status of 0-2. A multidisciplinary decision that active treatment was warranted was required. Key exclusion criteria were a pre-treatment estimated glomerular filtration rate of less than 30 mL/min per 1·73 m2, previous systemic therapies for renal cell cancer, previous high-dose radiotherapy to an overlapping region, tumours larger than 10 cm, and direct contact of the renal cell cancer with the bowel. Patients received either a single fraction SABR of 26 Gy for tumours 4 cm or less in maximum diameter, or 42 Gy in three fractions for tumours more than 4 cm to 10 cm in maximum diameter. The primary endpoint was local control, defined as no progression of the primary renal cell cancer, as evaluated by the investigator per Response Evaluation Criteria in Solid Tumours (version 1.1). Assuming a 1-year local control of 90%, the null hypothesis of 80% or less was considered not to be worthy of proceeding to a future randomised controlled trial. All patients who commenced trial treatment were included in the primary outcome analysis. This trial is registered with ClinicalTrials.gov, NCT02613819, and has completed accrual.

FINDINGS

Between July 28, 2016, and Feb 27, 2020, 70 patients were enrolled and initiated treatment. Median age was 77 years (IQR 70-82). Before enrolment, 49 (70%) of 70 patients had documented serial growth on initial surveillance imaging. 49 (70%) of 70 patients were male and 21 (30%) were female. Median tumour size was 4·6 cm (IQR 3·7-5·5). All patients enrolled had T1-T2a and N0-N1 disease. 23 patients received single-fraction SABR of 26 Gy and 47 received 42 Gy in three fractions. Median follow-up was 43 months (IQR 38-60). Local control at 12 months from treatment commencement was 100% (p<0·0001). Seven (10%) patients had grade 3 treatment-related adverse events, with no grade 4 adverse events observed. Grade 3 treatment-related adverse events were nausea and vomiting (three [4%] patients), abdominal, flank, or tumour pain (four [6%]), colonic obstruction (two [3%]), and diarrhoea (one [1%]). No treatment-related or cancer-related deaths occurred.

INTERPRETATION

To our knowledge, this is the first multicentre prospective clinical trial of non-surgical definitive therapy in patients with primary renal cell cancer. In a cohort with predominantly T1b or larger disease, SABR was an effective treatment strategy with no observed local failures or cancer-related deaths. We observed an acceptable side-effect profile and renal function after SABR. These outcomes support the design of a future randomised trial of SABR versus surgery for primary renal cell cancer.

FUNDING

Cancer Australia Priority-driven Collaborative Cancer Research Scheme.

Low rate of severe-end-stage kidney disease after SABR for localised primary kidney cancer

BACKGROUND

Stereotactic ablative body radiotherapy (SABR) is an emerging treatment for patients with primary renal cell carcinoma (RCC). However, its impact on renal function is unclear. This study aimed to evaluate incidence and clinical factors predictive of severe to end-stage chronic kidney disease (CKD) after SABR for RCC.

METHODS AND MATERIALS

This was a Single institutional retrospective analysis of patients with diagnosed primary RCC receiving SABR between 2012-2020. Adult patients with no metastatic disease, baseline estimated glomerular filtration rate (eGFR) of ≥ 30 ml/min/1.73 m2, and at least one post-SABR eGFR at six months or later were included in this analysis. Patients with upper tract urothelial carcinoma were excluded. Primary outcome was freedom from severe to end-stage CKD, determined using the Kaplan-Meier estimator. The impact of baseline CKD, age, hypertension, diabetes, tumor size and fractionation schedule were assessed by Cox proportional hazard models.

RESULTS

Seventy-eight consecutive patients were included, with median age of 77.8 years (IQR 70-83), tumor size of 4.5 cm (IQR 3.9-5.8) and follow-up of 42.2 months (IQR 23-60). Baseline median eGFR was 58 mls/min; 55% (n = 43) of patients had baseline CKD stage 3 and the remainder stage 1-2. By last follow-up, 1/35 (2.8%) of baseline CKD 1-2, 7/27 (25.9%) CKD 3a and 11/16 (68.8%) CKD 3b had developed CKD stage 4-5. The estimated probability of freedom from CKD stage 4-5 at 1 and 5 years was 89.6% (CI 83.0-97.6) and 65% (CI 51.4-81.7) respectively. On univariable analysis, worse baseline CKD (p < 0.0001) and multi-fraction SABR (p = 0.005) were predictive for development of stage 4-5 CKD though only the former remained significant in multivariable model.

CONCLUSION

In this elderly cohort with pre-existing renal dysfunction, SABR achieved satisfactory nephron sparing with acceptable rates of severe to end-stage CKD. It can be an attractive option in patients who are medically inoperable.

Nephron-sparing ureteroscopic surgery vs. radical nephroureterectomy: comparable survival-outcomes in upper tract urothelial carcinoma

PURPOSE

This study investigates the utility of ureteroscopic surgery (URS) as an alternative to radical nephroureterectomy (RNU) in managing upper tract urothelial carcinoma (UTUC), with a focus on survival outcomes and re-evaluation of current the European Association of Urology guidelines criteria.

METHODS

We conducted a retrospective, multi-institutional review of 143 UTUC patients treated with URS (n = 35) or RNU (n = 108). Clinicopathological factors were analyzed, and survival outcomes were assessed using Kaplan-Meier analysis and Cox proportional-hazards models.

RESULTS

The median follow-up period was 27 months. Overall survival (OS) and radiographic progression-free survival (rPFS) were comparable between the URS and RNU groups (OS: HR 2.42, 95% CI 0.63-9.28, P = 0.0579; rPFS: HR 1.82, 95% CI 0.60-5.47, P = 0.1641). URS conferred superior renal function preservation. In patients characterized by factors such as radiographically invisible lesions, negative cytology, pTa stage, low-grade tumors, and multiple lesions, the OS outcomes with URS were comparable to those with RNU as follows: radiographically invisible lesions (P = 0.5768), negative cytology (P = 0.7626), pTa stage (P = 0.6694), low-grade tumors (P = 0.9870), and multiple lesions (P = 0.8586).

CONCLUSION

URS offers survival outcomes similar to RNU, along with better renal function preservation, especially in low-risk UTUC patients. These findings underscore the urgency of re-evaluating the current EAU guidelines and encourage further research into determining the ideal patient selection for URS in UTUC treatment.

Risk factors and predictive model for acute kidney Injury Transition to acute kidney disease in patients following partial nephrectomy

PURPOSE

Acute kidney disease (AKD) is believed to be involved in the transition from acute kidney injury (AKI) to chronic kidney disease in general populations, but little is understood about this possibility among kidney surgical populations. This study aimed to elucidate the incidence of AKD after partial nephrectomy and risk factors that promote the AKI to AKD transition.

METHODS

From January 2010 to January 2020, this study retrospectively collected a dataset of consecutive patients with renal masses undergoing partial nephrectomy in 4 urological centers. Cox proportional regression analyses were adopted to identify risk factors that promoted the AKI to AKD transition. To avoid overfitting, the results were then verified by logistic least absolute shrinkage and selection operator (LASSO) regression. A nomogram was then constructed and validated for AKI to AKD transition prediction.

RESULTS

AKI and AKD occurred in 228 (21.4%) and 42 (3.9%) patients among a total of 1062 patients, respectively. In patients with AKI, multivariable Cox regression analysis and LASSO regression identified that age (HR 1.078, 1.029-1.112, p < 0.001), baseline eGFR (HR 1.015, 1.001-1.030, p < 0.001), RENAL score (HR1.612, 1.067-2.437, p = 0.023), ischemia time > 30 min (HR 7.284, 2.210-23.999, p = 0.001), and intraoperative blood loss > 300ml (HR 8.641, 2.751-27.171, p < 0.001) were risk factors for AKD transition. These five risk factors were then integrated into a nomogram. The nomogram showed excellent discrimination, calibration, and clinical net benefit ability.

CONCLUSION

Around 3.9% patients following partial nephrectomy would transit from AKI to AKD. Intraoperative blood loss and ischemia time need to be diminished to avoid on-going functional decline. Our nomogram can accurately predict the transition from AKI to AKD.

Chapter 4: CKD treatment in cancer survivors, from Clinical Practice Guidelines for the Management of Kidney Injury During Anticancer Drug Therapy 2022

Chronic kidney disease (CKD) is one of the most disabling disorders with significant comorbidity and mortality. Incidence and prevalence of CKD in cancer survivors are remarkably high in both adults and pediatric patients. The reasons for this high incidence/prevalence are multifold but kidney damage by cancer itself and cancer treatment (pharmacotherapy/surgery/radiation) are the main reasons. Since cancer survivors commonly have significant comorbidities, risk of cancer recurrence, limited physical function or life expectancy, special attentions should be paid when considering the treatment of CKD and its complications. Especially, shared decision-making should be considered when selecting the renal replacement therapies with as much information/facts/evidence as possible.

Chapter 1: Evaluation of kidney function in patients undergoing anticancer drug therapy, from clinical practice guidelines for the management of kidney injury during anticancer drug therapy 2022

The prevalence of CKD may be higher in patients with cancer than in those without due to the addition of cancer-specific risk factors to those already present for CKD. In this review, we describe the evaluation of kidney function in patients undergoing anticancer drug therapy. When anticancer drug therapy is administered, kidney function is evaluated to (1) set the dose of renally excretable drugs, (2) detect kidney disease associated with the cancer and its treatment, and (3) obtain baseline values for long-term monitoring. Owing to some requirements for use in clinical practice, a GFR estimation method such as the Cockcroft-Gault, MDRD, CKD-EPI, and the Japanese Society of Nephrology's GFR estimation formula has been developed that is simple, inexpensive, and provides rapid results. However, an important clinical question is whether they can be used as a method of GFR evaluation in patients with cancer. When designing a drug dosing regimen in consideration of kidney function, it is important to make a comprehensive judgment, recognizing that there are limitations regardless of which estimation formula is used or if GFR is directly measured. Although CTCAEs are commonly used as criteria for evaluating kidney disease-related adverse events that occur during anticancer drug therapy, a specialized approach using KDIGO criteria or other criteria is required when nephrologists intervene in treatment. Each drug is associated with the different disorders related to the kidney. And various risk factors for kidney disease associated with each anticancer drug therapy.

Novel Biomarkers for Early Detection of Acute Kidney Injury and Prediction of Long-Term Kidney Function Decline after Partial Nephrectomy

Background: Identifying acute kidney injury (AKI) within few hours of onset is certainly helpful. However, early prediction of a long-term eGFR decline may be an even more important goal. Our aim was to identify and compare serum [creatinine, kineticGFR, cystatin C, neutrophil gelatinase–associated lipocalin (NGAL)] and urinary (NephroCheck, NGAL, proteinuria, albuminuria, acantocytes at urinary sediment) predictors of AKI that might efficiently predict long-term GFR decline after robotic Nephron-Spearing Surgery (rNSS). Methods: Monocentric prospective observational study. Patients scheduled for rNSS for suspected localized Renal Cell Carcinoma from May 2017 to October 2017 were enrolled. Samples were collected preoperatively and postoperatively (timepoints: 4 h, 10 h, 24 h, 48 h), while kidney function was re-assessed up to 24 months. Results: 38 patients were included; 16 (42%) developed clinical AKI. The eGFR decline at 24 months was more pronounced after postoperative AKI (−20.75 vs. −7.20, p < 0.0001). KineticGFR at 4 h (p = 0.008) and NephroCheck at 10 h (p = 0.001) were, at multivariable linear regression analysis, efficient predictors of post-operative AKI and long-term eGFR decline if compared to creatinine (R2 0.33 vs. 0.04). Conclusions: NephroCheck and kineticGFR have emerged as promising noninvasive, accurate, and early biomarkers of postoperative AKI and long-term GFR decline after rNSS. Combining NephroCheck and kineticGFR in clinical practice would allow to identify high risk of postoperative AKI and long-term GFR decline as early as 10 h after surgery.

Renal functional and cardiovascular outcomes of partial nephrectomy versus radical nephrectomy for renal tumors: a systematic review and meta-analysis

This systematic review and meta-analysis aimed to evaluate the postoperative renal and cardiovascular outcomes of partial nephrectomy (PN) versus radical nephrectomy (RN) for the treatment of renal carcinoma. A systematic literature search was performed on scientific databases including Scopus, Web of Science, MEDLINE, and EMBASE from their inception to September 2021. Studies comparing renal and cardiovascular outcomes between PN and RN in patients with renal cancer were included. The generic inverse variance method with random-effects models was used to determine the pooled hazard ratios and odds ratio for each outcome. Quality Assessment for observational studies was guided by the New-Castle Ottawa Scale. Overall, a total of 31 studies (n=51,866) reported renal outcomes, while 11 studies (n= 101,678) reported cardiovascular outcomes. When compared to PN, RN had a higher rate of new-onset postoperative EGFR <60 mL/min/1.73 m² (HR 3.39; CI 2.45 - 4.70; I²=93%; P=<0.00001) and EGFR <45 mL/min/1.73 m² (HR 4.70; CI 2.26 - 9.79; I²=98%; P=<0.0001). No difference was observed in new-onset advanced kidney disease and end-stage renal disease. A 19% reduction in cardiovascular events was observed in the PN group (HR 0.81; CI 0.70 - 0.93, P=0.002). No protective effect of PN was observed in new-onset or worsening hypertension (HR 0.85; CI 0.64 - 1.14, P=0.28) nor myocardial infarction (HR 0.86; CI 0.71 - 1.04, P=0.13). PN was associated with a decreased risk of postoperative early-stage CKD and cardiovascular events compared with RN. However, no benefit of PN over RN was observed in advanced CKD, new-onset or worsening hypertension, myocardial infarction, and cardiovascular mortality.

Renal Functional Outcomes in Patients With Angiomyolipomas: Surveillance vs Embolization vs Nephrectomy

OBJECTIVE

To investigate renal functional outcomes of surveillance, embolization, and surgery for angiomyolipomas (AML).

METHODS

Longitudinal data regarding patients with AML were analyzed retrospectively in this 2-center study. Demographic, radiographic, and functional data were tabulated according to treatment type. Primary outcome was change in renal function from diagnosis to within 6 months postdiagnosis (interim) and to latest glomerular filtration rate (GFR) assessment.

RESULTS

318 patients were diagnosed with AMLs; mean follow-up was 6.2 years. 184 patients (57.9%) were managed with surveillance, 30 (9.4%) underwent embolization, and 103 (32.4%) underwent surgery (91 partial nephrectomy; 12 radical nephrectomy). Baseline characteristics, including tumor size, age, and race differed between the 3 groups (P<.05). Surveilled AMLs were smaller (P<.001) than the intervention groups: 1.9 cm vs 5.4 cm (embolization) and 4.9 cm (surgery). Greater interim decreases in GFR were observed following intervention with embolization (-14.0%) or surgery (-11.8%), when compared with surveillance (-4.1%); however, this was not statistically significant (P=.19). Latest GFR was also reduced more (P=.02) with embolization (-14.1%) and surgery (-14.7%) when compared to surveillance (-6.0%). At latest determination, chronic kidney disease progression by at least one stage occurred in 37.8% overall, including 33.7% of surveilled patients, and was not statistically different across the three cohorts (P=.074).

CONCLUSION

Within the study limitations, surveillance appears to be appropriate for most AML patients; embolization and surgical intervention should be reserved for selected patients with large and/or symptomatic AML. Renal functional deterioration is common in patients with AML, whether managed with surveillance, embolization, or surgery. Long-term monitoring of renal function should be obligatory for all AML patients.

Comparative risk of acute kidney injury among cancer patients treated with immune checkpoint inhibitors

With the development and introduction of immune checkpoint inhibitors (ICIs) in cancer patients, immune-related side effects have increasingly attracted attention. However, the risks of immune-related renal toxicity are poorly characterized. In this study, we performed a network meta-analysis (NMA) of ICI-related randomized clinical trials (RCTs) to elucidate the comparative risk of acute kidney injury (AKI) in cancer patients receiving different ICIs. We also sought to identify other factors potentially affecting the risk of AKI. PubMed and EMBASE were searched for peer-reviewed trial reports published between January 2000 and May 2021. Eligible studies were RCTs studying ICIs in cancer patients and reporting AKI data. We performed a frequentist NMA to evaluate the risk ratios for grade 1-5 and grade 3-5 AKI between the treatment groups. We also assessed the absolute incidence of AKI in the ICI-containing arm using traditional direct meta-analysis. Once significant heterogeneity was detected in a traditional direct meta-analysis, multivariable meta-regression analysis was applied to identify factors that significantly affected the absolute incidence of AKI. A total of 85 RCTs were included in this study. In the NMA for the risk of grade 1-5 and 3-5 AKI, ipilimumab showed a significantly higher risk than avelumab and durvalumab, whereas 1 mg/kg nivolumab plus 3 mg/kg ipilimumab (N1I3) showed a significantly higher risk than other groups. In terms of treatment ranking, durvalumab ± low-dose tremelimumab and avelumab were consistently among the top three safest treatments for grade 1-5 or 3-5 AKI, whereas N1I3, ipilimumab and tremelimumab were consistently among the top three treatments with the highest risk for grade 1-5 or 3-5 AKI. Compared with other cancers, renal cell carcinoma and urothelial carcinoma showed a significantly higher risk of AKI. The incidence of AKI was significantly higher with ICI+chemotherapy than with ICI monotherapy. In this NMA involving large-scale up-to-date ICI trials, we demonstrated the comparative safety of existing ICI drugs for grade 1-5 and grade 3-5 AKI. Based on data from the ICI arms of these trials, we also revealed several potential risk factors for immune-related AKI, including tumor type and treatment paradigm.

The incidence and risk factors of chronic kidney disease after radical nephrectomy in patients with renal cell carcinoma

Background

Radical nephrectomy (RN) is the standard treatment for localized renal cell carcinoma. The decrease in nephrons from RN could lead to postoperative chronic kidney disease (CKD). In this study, we aim to investigate the incidence and risk factors for CKD in patients who have received RN.

Methods

A Total of 1233 patients underwent radical nephrectomy in Zhejiang Provincial People’s Hospital from January 2010 to December 2018. Those who had an abnormal renal function before surgery or were lost to follow-up were excluded. Five hundred patients were enrolled in the end. eGFR was calculated using the abbreviated MDRD equation. CKD was defined as eGFR less than 60 ml/min/1.73m². The incidence of postoperative CKD was estimated using the Kaplan-Meier method. The independent risk factors for CKD occurrence were determined through logistic multivariate regression analysis.

Results

Patients were followed up for a median of 40 month (3–96 months), with CKD occurring in 189 cases. The 5-year cumulative incidence of CKD was 43.4%. There was a significant difference between these189 patients and the remaining patients without post nephrectomy CKD in terms of age, sex, weight, and preoperative eGFR(P<0.05). Multivariate regression analysis showed that age (OR = 1.038, 95%CI = 1.002–1.076), preoperative eGFR of the contralateral kidney (OR = 0.934, 95%CI = 0.884–0.988) and Immediate postoperative eGFR (OR = 0.892, 95%CI = 0.854–0.931) were independent risk factors for postoperative CKD.

Conclusions

The incidence of CKD after radical nephrectomy was not uncommon. Age, preoperative eGFR of the contralateral kidney and Immediate postoperative eGFR are independent risk factors for postoperative CKD.

Evaluation of Renal Function after Partial Nephrectomy and Detection of Clinically Significant Acute Kidney Injury

Background and Objectives: Consequences of partial nephrectomy (PN), intraoperative hypotension (IOH) and postoperative neutrophil to lymphocyte ratio (NLR) may cause postoperative acute kidney injury (AKI) and in long-term-chronic kidney disease (CKD). Our study aimed to identify the AKI incidence after PN, to find clinically significant postoperative AKI and renal dysfunction, and to determine the predictor factors. Materials and Methods: A prospective observational study consisted of 91 patients who received PN with warm ischemia, and estimated preoperative glomerular filtration rate (eGFR) ≥ 60 mL/min and without abnormal albuminuria. Results: 38 (41.8%) patients experienced postoperative AKI. Twenty-one (24.1%) patients had CKD upstage after 1 year follow-up. Sixty-seven percent of CKD upstage patients had AKI 48 h after surgery and 11% after 2 months. All 15 (16.5%) patients with CKD had postoperative AKI. With IOH, OR 1.07, 95% CI 1.03−1.10 and p < 0.001, postoperative NLR after 48 h (OR 1.50, 95% CI 1.19−1.88, p < 0.001) was the major risk factor of AKI. In multivariate logistic regression analysis, the kidney’s resected part volume (OR 1.08, 95% CI 1.03−1.14, p < 0.001) and IOH (OR 1.10, 95% CI 1.04−1.15, p < 0.001) were retained as statistically significant prognostic factors for detecting postoperative renal dysfunction. The independent risk factor for clinically significant postoperative AKI was only IOH (OR, 1.06; p < 0.001). Only AKI with the CKD upstage group has a statistically significant effect (p < 0.0001) on eGFR 6 and 12 months after surgery. Conclusions: The presence of AKI after PN is not rare. IOH and NLR are associated with postoperative AKI. The most important predictive factor of postoperative AKI is an NLR of over 3.5. IOH is an independent risk factor for clinically significant postoperative AKI and together with kidney resected part volume effects postoperative renal dysfunction. Only clinically significant postoperative AKI influences the reduction of postoperative eGFR after 6 and 12 months.

Quantitative morphometrics reveals glomerular changes in patients with infrequent segmentally sclerosed glomeruli

AIMS

Detection of one segmentally sclerosed glomerulus (SSG) identifies patients with focal segmental glomerulosclerosis (FSGS) but rare SSGs may be missed in kidney biopsies. It is unknown whether alterations of unaffected glomeruli in patients with infrequent SSG can be detected by quantitative morphometrics.

METHODS

We determined SSG frequency and obtained quantitative morphometrics in glomeruli without a pathologic phenotype in large kidney sections of non-involved kidney tissue from 137 patients undergoing total nephrectomy. We used multivariate modelling to identify morphometrics independently associated with increasing frequency of SSG and Receiver Operator Curve (ROC) analysis to determine the ability of quantitative morphometrics to identify patients with FSGS. We used the geometric distribution to estimate the sensitivity and specificity of a needle biopsy to identify patients with FSGS.

RESULTS

In seventy-one patients (51.8%), at least one SSG was observed, and of those, 39 (54.9%) had an SSG lesion in less than 2% of all glomeruli (mean of 249 glomeruli per specimen). Increasing percent of SSG was independently associated with decreasing podocyte density and increasing mesangial index in multivariate modelling. For infrequent SSG lesions (<1% of glomeruli), kidney biopsy could miss FSGS diagnosis more than 74% of the time, and podocyte density had an area under the curve (AUC) of 0.77, and mesangial index, an AUC of 0.79 to identify patients with FSGS.

CONCLUSIONS

More than half of patients had FSGS, although 30% had infrequent SSG. Quantitative morphometrics in glomeruli without pathology, such as podocyte density and mesangial index, identified patients with infrequent SSG and may serve as clinical markers to identify patients with FSGS.

Renal Morbidity Following Radical Cystectomy in Patients with Bladder Cancer

Background

Patients with chronic kidney disease (CKD) are poor candidates for standard treatments for muscle-invasive bladder cancer (MIBC) and may be more likely to experience adverse outcomes when diagnosed with MIBC.

Objective

To investigate factors associated with the development of advanced CKD following radical cystectomy.

Design setting and participants

Using national Veterans Health Administration utilization files, we identified 3360 patients who underwent radical cystectomy for MIBC between 2004 and 2018.

Outcome measurements and statistical analysis

We examined factors associated with the development of advanced CKD (estimated glomerular filtration rate [eGFR] of <30 ml/min/1.73 m²) after radical cystectomy using multivariable logistic and proportional hazard regression, with and without consideration of competing risks. We examined survival using Kaplan-Meier product limit estimates and proportional hazard regression.

Results and limitations

The median age at surgery was 67 yr and the mean preoperative eGFR was 69.1 ± 20.3 ml/min/1.73 m². Approximately three out of ten patients (n = 962, 29%) progressed to advanced CKD within 12 mo. Older age (hazard ratio [HR] per 5-yr increase 1.15, 95% confidence interval [CI] 1.10-1.20), preoperative hydronephrosis (HR 1.50, 95% CI 1.29-1.76), adjuvant chemotherapy (HR 1.19, 95% CI 1.00-1.41), higher comorbidity index (HR 1.13, 95% CI 1.11-1.16 per point), and lower baseline kidney function (HR 0.75, 95% CI 0.73-0.78) were associated with the development of advanced CKD. Baseline kidney function at the time of surgery was associated with survival. Generalizability is limited due to the predominantly male cohort.

Conclusions

Impaired kidney function at baseline is associated with progression to advanced CKD and mortality after radical cystectomy. Preoperative kidney function should be incorporated into risk stratification algorithms for patients undergoing radical cystectomy.

Patient summary

Impaired kidney function at baseline is associated with progression to advanced chronic kidney disease and mortality after radical cystectomy.

The effect of frailty on post-operative outcomes and health care expenditures in patients treated with partial nephrectomy

OBJECTIVE

To examine the effect of frailty on short-term post-operative outcomes and total hospital charges (THCs) in patients with non-metastatic renal cell carcinoma, treated with partial nephrectomy (PN).

METHODS

Within the National Inpatient Sample (NIS) database we identified 25,545 patients treated with PN from 2000 to 2015. We used the Johns Hopkins Adjusted Clinical Groups (ACG) frailty-defining indicator and we examined the rates of frailty over time, as well as its effect on overall complications, major complications, blood transfusions, non-home-based discharge, length of stay (LOS) and THCs. Time trends and multivariable logistic, Poisson and linear regression models were applied.

RESULTS

Overall, 3574 (14.0%) patients were frail, 2677 (10.5%) were older than 75 years and 2888 (11.3%) had Charlson comorbidity index (CCI) ≥ 2. However, the vast majority of frail patients were neither elderly nor comorbid (83%). Rates of frail patients treated with PN increased over time, from 8.3 in 2000 to 18.1% in 2015 (all p < 0.001). Frail patients showed higher rates of overall complications (43.5 vs. 30.3%), major complications (16.6 vs. 9.8%), blood transfusions (11.6 vs 8.3%) and non-home-based discharge (9.9 vs. 5.4%). longer LOS [4 (IQR: 3-6) vs. 4 (IQR: 2-5) days] and higher THCs ($43,906 vs. $38,447 - all p < 0.001). Moreover, frailty status independently predicted overall complications (OR: 1.73), major complications (OR: 1.63), longer LOS (RR: 1.07) and higher THCs (RR: +$7506). Finally, a dose-response on the risk of suboptimal surgical outcomes was shown in patients with multiple risk factors.

CONCLUSIONS

One out of seven patients is frail at time of surgery and this rate is on the rise. Moreover, frailty is associated with adverse outcomes after PN. In consequence, preoperative assessment of frailty status should be implemented, to identify patients who may benefit from pre- or postoperative measures aimed at improving surgical outcomes in this patient population.

SGLT2 Inhibition in Patients With Type 2 Diabetes Mellitus Post-Nephrectomy: A Single-Center Case Series

Background:

Nephrectomy is the mainstay of treatment for many kidney cancers, but has been correlated with increased incidence of acute kidney injury (AKI) and chronic kidney disease (CKD). Recently, sodium-glucose cotransporter-2 (SGLT2) inhibition has been shown to decrease the incidence of end-stage kidney disease and death in people with type 2 diabetes mellitus (T2D). However, at present, there has been no description of the use of SGLT2 inhibition in patients with T2D and solitary kidney despite the high risk of CKD progression.

Objective:

To characterize the use of SGLT2 inhibition and kidney function in a series of patients with T2D with prior nephrectomy for renal cell carcinoma (RCC).

Design:

Retrospective case series.

Setting:

University hospital outpatient onco-nephrology clinic.

Patients:

Patients post-nephrectomy for RCC with T2D who were prescribed an SGLT2 inhibitor.

Measurements:

Serum creatinine, albumin to creatinine ratio (ACR), HgA1c, and blood pressure measurements.

Methods:

Patients post-nephrectomy with incident use of SGLT2 inhibitor were identified from an existing registry of patients followed in the Onco-Nephrology Clinic at our institution from May 2019 to March 2021. Demographics, medication use, time since nephrectomy, cancer diagnosis, serum creatinine, ACR measurements, and blood pressure measurements were extracted from electronic medical records.

Results:

Five patients were identified who had initiated SGLT2 inhibition post-nephrectomy. All patients were male, had T2D, and a prior history of hypertension. Renal cell carcinoma was the clinical indication for nephrectomy in all patients. None of patients were prescribed diuretics, and all were receiving renin-angiotensin system (RAS) inhibition therapies. The time from nephrectomy to SGLT2 inhibitor initiation ranged from 5 to 74 months. Baseline mean estimated glomerular filtration rate (eGFR) values were 49 mL/min/1.73 m² (95% confidence interval [CI]: 31.5-66.5), and mean ACRs were 8.7 mg/mmol (95% CI: 0.6-16.9). After 6 months of SGLT2 inhibition, the mean eGFR and ACR values were 58 mL/min/1.73 m² (95% CI: 29.7-86.2) and 23.8 mg/mmol (95% CI: 0-60), respectively. After 16 to 18 months of follow-up (4 patients), the mean eGFR was 56 mL/min/1.73 m² (95% CI: 37.3-74.7), and mean ACR was 10.5 (95% CI: 0-30.5), similar to baseline values before SGTL2i therapy initiation. At baseline, mean systolic blood pressure was 128 mm Hg (95% CI: 118.3-140.9) and remained similar after 12 months of treatment (mean 131 mm Hg [95% CI: 112.3-149.7]). There were no adverse events related to AKI, electrolyte disturbances, ketoacidosis, or genitourinary infections during the 18-month follow-up period.

Limitations:

Small sample size, lack of a comparison group, and the variable timing of clinical data collection, including eGFR levels following initiation of SGLT2 inhibition.

Conclusions:

SGLT2 inhibition is becoming a standard component of nephrology care to reduce kidney function decline, cardiovascular risk, and mortality. To our knowledge, our report is the first to provide longitudinal data on SGLT2 inhibitor usage in patients with T2D and solitary kidneys post-nephrectomy. Larger prospective studies are needed to determine the efficacy and safety of SGLT2 inhibition strategies for kidney protection in patients post-nephrectomy.

Risk of Postoperative Renal Failure in Radical Nephrectomy and Nephroureterectomy: A Validated Risk Prediction Model

INTRODUCTION

The study aimed to construct and validate a risk prediction model for incidence of postoperative renal failure (PORF) following radical nephrectomy and nephroureterectomy.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database years 2005-2014 were used for the derivation cohort. A stepwise multivariate logistic regression analysis was conducted, and the final model was validated with an independent cohort from the ACS-NSQIP database years 2015-2017.

RESULTS

In cohort of 14,519 patients, 296 (2.0%) developed PORF. The final 9-factor model included age, gender, diabetes, hypertension, BMI, preoperative creatinine, hematocrit, platelet count, and surgical approach. Model receiver-operator curve analysis provided a C-statistic of 0.79 (0.77, 0.82; p < 0.001), and overall calibration testing R2 was 0.99. Model performance in the validation cohort provided a C-statistic of 0.79 (0.76, 0.81; p < 0.001).

CONCLUSION

PORF is a known risk factor for chronic kidney disease and cardiovascular morbidity, and is a common occurrence after unilateral kidney removal. The authors propose a robust and validated risk prediction model to aid in identification of high-risk patients and optimization of perioperative care.

Functional adaptation after kidney tissue removal in patients is associated with increased plasma atrial natriuretic peptide concentration

BACKGROUND

Following nephrectomy, the remaining kidney tissue adapts by an increase in GFR. In rats, hyperfiltration can be transferred by plasma. We examined whether natriuretic peptides (ANP, BNP) increase in plasma proportionally with kidney mass reduction and, if so, whether the increase relates to an increase in GFR.

METHODS

Patients (n = 54) undergoing partial or total unilateral nephrectomy at two Danish centers were followed for one year in an observational study. Glomerular filtration rate was measured before, 3, and 12 months after surgery. Natriuretic propeptides (proANP and proBNP) and aldosterone were measured in plasma before and at 24 hours, five days, 21 days, three months, and 12 months. Cyclic GMP was determined in urine.

RESULTS

There was no baseline difference in GFR between total- and partial nephrectomy (90.1 mL/min ±14.6 vs. 82.9±18, p = 0.16). Single-kidney GFR increased after 3 and 12 months (12.0 and 11.9 ml/min/1.73m2, +23.3%). There was no change in measured GFR 3 and 12 months after partial nephrectomy. ProANP and proBNP increased 3-fold 24h after surgery and returned to baseline after five days. The magnitude of acute proANP and proBNP increases did not relate to kidney mass removed. ProANP, not proBNP, increased 12 months after nephrectomy. Plasma aldosterone and urine cGMP did not change. Urine albumin/creatine ratio increased transiently after partial nephrectomy. Blood pressure was similar between groups.

CONCLUSION

ANP and BNP increase acutely in plasma with no relation to degree of kidney tissue ablation. After 1year, only unilateral nephrectomy patients display increased plasma ANP which could support adaptation.

Comparison of Differential Functional Outcomes After Partial Nephrectomy Between Moderate and High Complex Renal Tumor Evaluated with Diethylenetriamine Pentaacetic Acid Scan: A Propensity Score Matched Analysis

OBJECTIVE

The aim of this study was to compare functional outcomes after partial nephrectomy (PN) between moderate and high complex renal tumors evaluated with a diethylenetriamine pentaacetic acid (DTPA) scan [moderate vs. high: RENAL nephrometry score (RNS) 7-9 vs. 10-12].

METHODS

From January 2004 to December 2019, 471 patients with an RNS of 7-9 (moderate) and 164 patients with an RNS of 10-12 (high) who underwent PN were analyzed for renal function outcomes. The glomerular filtration rate (GFR) was measured using a DTPA scan and calculated the GFR using the Modification of Diet in Renal Disease (MDRD) formula, respectively. Trifecta/pentafecta outcome, recurrence-free survival, and overall survival were compared after propensity score matched analysis (PSMA).

RESULTS

After PSMA, 156 cases in each group were matched without significant difference in the preoperative factor. At the postoperative first year, there was no significant difference in the trifecta (p = 0.320), MDRD-based (p = 0.729), or DTPA-based pentafecta achievement rate (p = 0.964) between groups. At postoperative 5 years, DTPA-based total GFR (93.6% vs. 93.8%) and the operated kidney GFR preservation rate (89.9% vs. 81.7%) did not differ significantly (p > 0.05). Kaplan-Meier survival analysis showed no significant differences in survival outcomes (p > 0.05). Significant predictors of de novo chronic kidney disease (CKD) stage 3 or higher at the postoperative first year were age [hazard ratio (HR) 1.10, 95% confidence interval (CI) 1.03-1.17, p = 0.005] and preoperative DTPA-based total GFR (HR 0.94, 95% CI 0.91-0.98, p = 0.001).

CONCLUSION

High complex tumors can be treated with PN without significant deterioration in renal function. The postoperative function of the operated kidney was preserved by up to 80% in the long term compared with the preoperative period. However, PN should be selectively performed with caution to avoid the occurrence of postoperative CKD.

Estimated Glomerular Filtration Rate as a Prognostic Factor in Urothelial Carcinoma of the Upper Urinary Tract: A Systematic Review and Meta-Analysis

Preoperative renal function is associated with worse outcomes in patients undergoing radical nephroureterectomy (RNU). The purpose of this systemic review and meta-analysis was to determine the association of preoperative renal function with oncological outcome in patients who underwent RNU. We searched articles published up to March 2021 in PubMed, Scopus, and Embase by combining "urothelial carcinoma", "radical nephroureterectomy", and "estimated glomerular filtration rate". We also manually screened the reference list for publications following general guidelines recommended by the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement. The relationship between preoperative renal function and survival was expressed as overall survival (OS), progression-free survival (PFS), and cancer-specific survival (CSS). This review and meta-analysis included 13 studies involving a total of 4668 patients who received RNU. Pooled analysis showed significant negative association of preoperative renal function with PFS (HR: 1.51, 95% CI: 1.23-1.80, p < 0.00001), CSS (HR: 1.63, 95% CI: 1.38-1.92, p < 0.00001), and OS (HR: 1.22, 95% CI: 1.10-1.35, p < 0.00001). Patients with upper tract urothelial carcinoma (UTUC) who received RNU showed a significant negative association of preoperative renal function with survival.

Immune-related adverse events and kidney function decline in patients with genitourinary cancers treated with immune checkpoint inhibitors

BACKGROUND

In patients with genitourinary cancers, the effect of immune checkpoint inhibitors (ICIs) on kidney function is unknown.

PATIENTS AND METHODS

This is a retrospective cohort study of patients with renal cell carcinoma (RCC) and urothelial carcinoma who received ICIs at two major cancer centers between 2012 and 2018. Cumulative incidence and Fine and Gray subdistribution hazard models were performed to determine predictors of the co-primary outcomes, (1) acute kidney injury (AKI) and (2) sustained estimated glomerular filtration rate (eGFR) loss, defined as a >20% decline in eGFR sustained ≥90 days. We also determined the association between immune-related adverse events (irAE) and adverse kidney outcomes among patients surviving ≥1 year.

RESULTS

637 patients were included; 320 (50%) patients had RCC and 317 (50%) patients had urothelial carcinoma. Half of the cohort had eGFR<60 mL/min/1.73 m² at baseline. irAEs, AKI, and sustained eGFR loss were common, occurring in 33%, 25% and 16%, respectively. Compared to patients with urothelial carcinoma, patients with RCC were more likely to develop irAEs (aHR 1.61, 95% CI 1.20-2.18) and sustained eGFR loss (aHR 1.97, 95% CI 1.24-3.12), but not AKI (aHR 1.53, 95% CI 0.97-2.41). Among patients surviving ≥1 years, experiencing a non-renal irAE was associated with a significantly higher risk of sustained eGFR loss (aHR 1.71, 95% CI 1.14-2.57).

CONCLUSION

AKI and sustained eGFR loss are common in patients with genitourinary cancers receiving ICIs. irAEs may be a novel risk factor for kidney function decline among patients receiving ICIs.

Acute Kidney Injury in Patients With Cancer: A Review of Onconephrology

Over the past 2 decades, significant research and advancements have been made in oncology and its therapeutics. Thanks to novel diagnostic methods, treatments, and supportive measures, patients with cancer live longer and have a better quality of life. However, an unforeseen consequence of this progress has been increasing medical complications, including acute kidney injury. The purpose of this review is to provide an overview of the epidemiology and most common causes of acute kidney injury in patients with cancer unrelated to oncological treatment.

Unexpected Outcomes of Renal Function after Radical Nephrectomy: Histology Relevance along with Clinical Aspects

Acute kidney injury (AKI) and chronic kidney disease (CKD) are common events after radical nephrectomy (RN). In this study we aimed to predict AKI and CKD after RN relying on specific histological aspects. We collected data from a cohort of 144 patients who underwent radical nephrectomy. A histopathological review of the healthy part of the removed kidney was performed using an established chronicity score (CS). Logistic regression analyses were performed to predict AKI after RN, while linear regression analysis was adopted for estimated glomerular filtration rate (eGFR) variation at 1 year. The outcomes of the study were to determine variables correlated with AKI onset, and with eGFR decay at 1 year. The proportion of AKI was 64%. Logistic analyses showed that baseline eGFR independently predicted AKI (odds ratio 1.04, 95%CI 1.02:1.06). Moreover, AKI (Beta −16, 95%CI −21:−11), baseline eGFR (Beta −0.42, 95%CI −0.52:−0.33), and the presence of arterial narrowing (Beta 10, 95%CI 4:15) were independently associated with eGFR decline. Our findings showed that AKI onset and eGFR decline were more likely to occur with higher baseline eGFR and lower CS, highlighting that RN in normal renal function patients represents a more traumatic event than its CKD counterpart.

Serum uric acid variability increases the risk of postoperative chronic kidney disease in patients with renal cell carcinoma after radical nephrectomy

OBJECTIVE

Serum uric acid (SUA) level is associated with the progression of chronic kidney disease (CKD). However, little is known about the predictive value of SUA variability for postoperative CKD in patients with renal cell carcinoma after radical nephrectomy. We aimed to investigate the association of SUA variability with postoperative CKD in this population.

METHOD

85 patients with preoperative estimated glomerular filtration rate (eGFR)≥60 ml/min/1.73 m² were enrolled in this single-center retrospective study and followed up for at least 6 months. Intra-individual SUA variability was defined as the standard deviation (SD) of SUA and the patients were stratified into three groups according to the tertiles of SUA SD (the lower, middle and upper tertile). The association of SUA variability with postoperative CKD, defined as an eGFR<60 ml/min/1.73m², was analyzed by Cox proportional hazard models and Kaplan-Meier analyses.

RESULTS

After a median follow-up time of 24(10-43) months, 44(51.7%) patients developed postoperative CKD. Kaplan-Meier curves showed that patients in the lower tertile had a longer CKD-free survival time [median CKD-free survival time 74(52.2-95.8) months] than those in the middle tertile [38(19.2-56.8) months] and upper tertile [21(17.9-24.1) months] (overall generalized Wilcoxon test: P=0.001; lower vs middle tertile: P=0.001; lower vs upper tertile: P<0.001). Adjusted Cox analyses indicated that increasing SUA SD tertiles were associated with a higher risk of postoperative CKD independent of baseline SUA, mean SUA during follow-up and other confounding variables. Compared with patients in the lower tertile, the risk for developing CKD increased by 4.6-fold for patients in the middle tertile and 7.9-fold in the upper tertile, respectively.

CONCLUSION

Increasing SUA variability was associated with an increased risk of postoperative CKD in patients with renal cell carcinoma after radical nephrectomy.

Partial Nephrectomy Versus Radical Nephrectomy for Clinical T2 or Higher Stage Renal Tumors: A Systematic Review and Meta-Analysis

OBJECTIVE

The choice of surgical method for clinically diagnosed T2 or higher stage kidney cancer remains controversial. Here, we systematically reviewed and collected published comparative studies on renal function, oncologic outcomes, and perioperative results of partial nephrectomy (PN) versus radical nephrectomy (RN) for larger renal tumors (T2 and above), and performed a meta-analysis.

EVIDENCE ACQUISITION

Following searches of PubMed, Web of Science, and Embase, the original studies on PN vs. RN in the treatment of T2 renal cancer were screened through strict inclusion and exclusion criteria. RevMan 5.4 was used for data analysis of the perioperative results, renal function, and oncologic outcomes of the two surgical methods for T2 renal tumor therapy. The weighted mean difference was used as the combined effect size for continuous variables, while the odds ratio (OR) or risk ratio (RR) was used as the combined effect size for binary variables. Both variables used a 95% confidence interval (CI) to estimate statistical accuracy. In cases with low heterogeneity, the fixed-effects model was used to pool the estimated value; otherwise, the random-effects model was used when significant heterogeneity was detected.

RESULTS

Fifteen retrospective studies including 5,056 patients who underwent nephrectomy (PN: 1975, RN: 3081) were included. The decline in estimated GFR (eGFR) after PN was lower than RN [(MD: -11.74 ml/min/1.73 m2; 95% CI: -13.15, -10.32; p < 0.00001)]. The postoperative complication rate of PN was higher than that of PN (OR: 2.09; 95% CI: 1.56, 2.80; p < 0.00001)], and the postoperative overall survival (OS) of PN was higher than that of RN (HR: 0.77; 95% CI: 0.65, 0.90; p = 0.002), and tumor recurrence (RR, 0.69; 95% CI: 0.53, 0.90; p = 0.007). No obvious publication bias was found in the funnel chart of the OS rates of the two groups of patients.

CONCLUSIONS

PN is beneficial for patients with T2 renal tumors in terms of OS and renal function protection. However, it is also associated with a higher risk of surgical complications.

Evaluation of functional outcome of bilateral kidney tumors after sequential surgery

Background

There are limited data concerning patients treated with sequential bilateral kidney surgery. Current guidelines still lack an optimal surgical sequencing approach. We evaluated renal functional outcomes after sequential partial nephrectomy (PN) and radical nephrectomy (RN) in patients with bilateral renal cell carcinoma (RCC).

Methods

A propensity score matched cohort of 267 patients (synchronous bilateral RCCs, N = 44 [88 lesions]; metachronous bilateral, N = 45 [90 lesions]; unilateral, N = 178) from two tertiary institutions were retrospectively analyzed. Synchronous bilateral RCCs were defined as diagnosis concomitantly or within 3 months of former tumor. Renal functional outcomes were defined as estimated glomerular filtration rate (eGFR) changes and de novo chronic kidney disease (CKD, stage ≥3) after surgery. Renal functional outcomes and clinical factors predicting de novo CKD were assessed using descriptive statistics and Cox regression analysis.

Results

In subgroup of bilateral RCCs, patients underwent sequential PN (N = 48), PN followed by RN (N = 8), or RN followed by PN (N = 25). Final postoperative estimated glomerular filtration rates (eGFRs) were 79.4, 41.4, and 61.2 ml/minute/1.73 m2, respectively (p = 0.003). There were significant differences in eGFR decline from baseline and de novo chronic kidney disease (CKD stage ≥ III) among groups, with PN followed by RN group showing the worst functional outcomes (all p <  0.05). Moreover, sequential PN subgroup in bilateral RCC showed significantly higher rate of de novo CKD than unilateral RCC group (13.8% vs. 6.9%, p = 0.016). On multivariate analysis, hypertension (p = 0.010) and surgery sequence (PN followed by RN, p <  0.001) were significant predictors of de novo CKD.

Conclusions

The surgery sequence should be prudently determined in bilateral renal tumors. PN followed by RN showed a negative impact on renal functional preservation. Nephron-sparing surgery should be considered for all amenable bilateral RCCs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08324-3.

Three-dimensional Reconstruction of Renal Vascular Tumor Anatomy to facilitate accurate preoperative planning of partial nephrectomy

Objectives

To evaluate the role of three-dimensional (3D) reconstruction tumors and vessels of the kidneys in aiding the preoperative planning of partial nephrectomy.

Materials and methods

Patients with renal tumors to be treated with partial nephrectomy were included. Each patient underwent a preoperative computed tomography (CT) survey, and the reconstruction of each patient's 3D arteriography and 3D surface-rendered tumor was performed based on the CT images for preoperative surgical planning.

Results

A total of 6 patients, three with tumors of the right kidney and three with tumors of the left kidney, were enrolled in the study. The patients' mean age was 49.33 ± 4.03 years (range: 45-57 years), and their mean tumor size was 4.4 ± 1.84 cm (range: 2.2-6.8 cm). Four underwent robot-assisted laparoscopic partial nephrectomies, one underwent a traditional laparoscopic partial nephrectomy, and one underwent a radical nephrectomy through laparotomy. Their average postoperative hospital stay was 6.7 days (range: 3-10 days). No intraoperative or postoperative complications were noted. The renal function was preserved in all the patients, and none of the patients exhibited evidence of local recurrence during more than 6 years of follow-up.

Conclusions

3D arteriography fused with 3D surface-rendered tumor image navigation facilitates precise preoperative planning.

Does Reduced Renal Function Predispose to Cancer-specific Mortality from Renal Cell Carcinoma?

BACKGROUND

Recent publications have reported an association between increased renal cancer-specific mortality (CSM) and reduced renal function "below safety limits," and advocated for partial nephrectomy (PN) even for potentially aggressive/complex tumors. We hypothesize that this association may be related to confounding factors rather than a consequence of functional differences.

OBJECTIVE

To assess whether there is an independent association between preoperative estimated glomerular filtration rate (eGFR) or new baseline eGFR (NB-GFR) and CSM in patients undergoing PN or radical nephrectomy (RN).

DESIGN, SETTING, AND PARTICIPANTS

A single-center retrospective review was performed. All clinically and pathologically confirmed T1-T3a/N0/M0 renal cancer patients undergoing PN/RN (1999-2008, n = 1605) with adequate functional/oncological data were included.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint was CSM. Secondary endpoints were cancer recurrence (CR) and all-cause mortality (ACM). Cox regression analyses investigated endpoints and predictive factors.

RESULTS AND LIMITATIONS

The median age was 60 yr and 64% of patients were male. Comorbidities included hypertension (60%), cardiovascular disease (19%), diabetes (21%), and chronic kidney disease (22%). PN was performed in 954 patients (59%). The median preoperative eGFR and NB-GFR were 80 and 60 ml/min/1.73 m², respectively. Median tumor diameter was 3.6 cm (interquartile range [IQR] = 2.4, 5.5); 70% of tumors were clear cell and 40% were of high grade. Pathology revealed pT1-2/N0/M0 and pT3a/N0/M0 in 81% and 19%, respectively. The median follow-up among survivors was 11.5 yr (IQR = 4, 14). Cancer-specific survival, recurrence-free survival, and overall survival were 94%, 88%, and 73% at 10 yr, respectively. On multivariable analysis, increased age (hazard ratio [HR] = 1.03, p =  0.04), increased tumor size (HR = 1.24, p <  0.01), tumor grade 3/4 (HR = 3.17, p <  0.01), and clear-cell histology (HR = 2.92, p <  0.01) were associated with increased hazard of CSM. Neither preoperative eGFR nor NB-GFR was significantly associated with CSM or CR (all p >  0.1), while an increased preoperative eGFR was associated with reduced hazard of ACM (HR = 0.87, p <  0.01). Limitations include retrospective design and a potential selection bias.

CONCLUSIONS

Our data do not support oncological protection of greater preservation of renal function and confirm that unfavorable oncological outcomes for localized RCC are mostly associated with aggressive tumor characteristics.

PATIENT SUMMARY

We did not find an association between greater preservation of renal function and oncological outcomes for kidney cancer.

Endoscopic management versus radical nephroureterectomy for localized upper tract urothelial carcinoma in a high endemic region

Our aim was to analyze the clinical and survival differences among patients who underwent the two main treatment modalities, endoscopic ablation and radical nephroureterectomy. This study examined all patients who had undergone endoscopic management and RNU between Jul. 1988 and Mar. 2019 from the Taiwan UTUC registry. The inclusion criteria were low stage UTUC in RNU and all cases in endoscopic managed UTUC with a curative intent. The demographic and clinical characteristics were included for analysis. In total, 84 cases in the endoscopic group and 272 cases in the RNU group were enrolled for final analysis. The median follow-up period were 33.5 and 42.0 months in endoscopic and RNU group, respectively (p = 0.082). Comparison of Kaplan–Meier estimated survival curves between groups, the endoscopic group was associated with similar overall survival (OS), cancer specific survival (CSS), and intravesical recurrence free survival (IVRS) but demonstrated inferior disease free survival (DFS) (p = 0.188 for OS, p = 0.493 for CSS and p < 0.001 for DFS). Endoscopic management of UTUC was as safe as RNU in UTUC endemic region.

Effects of metabolic syndrome on renal function after radical nephrectomy in patients with renal cell carcinoma

PURPOSE

Nephrectomy, partial or radical, remains the standard treatment for renal cell carcinoma (RCC). However, increased risk of chronic kidney disease (CKD) must still be considered. This study aimed to evaluate the effects of concomitant metabolic syndrome (MetS) on renal function in patients with RCC after radical nephrectomy.

METHODS

Medical records of 310 patients who underwent radical nephrectomy for clear-cell RCC at 900th Hospital of the Joint Logistics Support Force, PLA from December 2012 to January 2017 were reviewed retrospectively. Estimated glomerular filtration rate (eGFR) and CKD stages were calculated at one week preoperative as baseline and then at postoperative 1 week, 3 months, 12 months and 24 months. MetS patients were identified and enrolled in the MetS group (n = 31), and a non-MetS group was selected by propensity score matching (n = 31). Non-neoplastic renal parenchyma specimens taken at least 2 cm from edge of tumor were evaluated.

RESULTS

Baseline characteristics between the two groups were comparable. At 24 months postoperative, mean eGFR levels of the MetS group were significantly lower than those in the non-MetS group (62.7 vs. 73.3 ml/min/1.73 m²; p = 0.004). CKD stages were still more severe in the MetS group than those in the non-MetS group (p = 0.006). The proportions of global sclerosis, tubular atrophy and interstitial fibrosis were all significantly more prevalent in MetS patients, compared to non-MetS patients (all p < 0.05).

CONCLUSION

In RCC patients with MetS, the possibility of declining eGFR and CKD progression must be considered after radical nephrectomy. Routine monitoring of renal function must be emphasized.

Predictors of long-term renal function after kidney surgery for patients with preoperative chronic kidney disease

INTRODUCTION

We evaluated the trajectory of estimated glomerular filtration rate (eGFR) after kidney surgery in patients with kidney cancer and chronic kidney disease (CKD).

METHODS

We identified 1204 consecutive patients in our institutional database with preoperative CKD undergoing partial or radical nephrectomy from 1998-2016. Postoperative eGFR was tracked, with patients censored when receiving dialysis or kidney transplantation. A multivariable mixed-effects models assessed associations between preoperative baseline patient and tumor characteristics, and longitudinal eGFR. The Kaplan-Meier method and multivariable Cox regression were used to estimate overall survival, cancer-specific survival, and cumulative incidence of dialysis.

RESULTS

Preoperatively, 892 (74.1%), 271 (22.5%), and 41 (3.4%) patients had CKD stage 3a, 3b, and 4/5, respectively. There were 55 patients dialyzed and 355 deaths (99 from kidney cancer). Median followup was 8.1 years, with 25 781 postoperative eGFR measurements. Factors associated with decreasing eGFR postoperatively included radical nephrectomy, male gender, older age, increased body mass index (BMI), and cardiovascular risk factors. We observed a significant interaction effect between time from surgery and preoperative CKD stage: the eGFR of stage 3a patients improved, while stage ≥3b declined (p<0.001). The two-year and five-year cumulative incidence of dialysis was 1.8% (1.1-2.6%) and 3.1% (2.2-4.2%), respectively. The cumulative incidence of dialysis, with death as a competing event, significantly differed by preoperative CKD stage.

CONCLUSIONS

Preoperative CKD stage ≥3b is independently associated with a higher risk of declining renal function, dialysis, and mortality. With careful selection, patients with preoperative CKD withstand kidney surgery with low rates of dialysis.

The link between kidney disease and cancer: complications and treatment

Acute and chronic kidney disease encompasses a complex set of diseases that can both lead to, and result from, cancer. In particular, kidney disease can arise from the use of chemotherapeutic agents. Many of the current and newly developed cancer chemotherapeutic agents are nephrotoxic and can promote kidney dysfunction, which frequently manifests during the terminal stages of cancer. Given the link between kidney disease and cancer development and treatment, the aim of this Review is to highlight the importance of multidisciplinary collaboration between oncologists and nephrologists to predict and prevent chemotherapeutic-induced nephrotoxicity. As new therapies are introduced to treat cancer, new renal toxicities require proper diagnosis and management. We anticipate that multidisciplinary collaborations will lead to the development and implementation of guidelines for clinicians to improve the therapeutic management of patients with both cancer and renal impairment.

Trends and Outcomes with Kidney Failure from Antineoplastic Treatments and Urinary Tract Cancer in France

BACKGROUND AND OBJECTIVES

Cancer survival is improving along with an increase in the potential for adverse kidney effects from antineoplastic treatments or nephrectomy. We sought to describe recent trends in the incidence of kidney failure related to antineoplastic treatments and urinary tract cancers and evaluate patient survival and kidney transplantation access.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We used the French Renal Epidemiology and Information Network registry to identify patients with kidney failure related to antineoplastic treatments or urinary tract cancer from 2003 to 2015. We identified 287 and 1157 cases with nephrotoxin- and urinary tract cancer-related kidney failure, respectively. The main study outcomes were death and kidney transplantation. After matching cases to two to ten controls (n=11,678) with other kidney failure causes for age, sex, year of dialysis initiation, and diabetes status, we estimated subdistribution hazard ratios (SHR) of each outcome separately for patients with and without active malignancy.

RESULTS

The mean age- and sex-adjusted incidence of nephrotoxin-related kidney failure was 0.43 (95% CI, 0.38 to 0.49) per million inhabitants and 1.80 (95% CI, 1.68 to 1.90) for urinary tract cancer-related kidney failure; they increased significantly by 5% and 2% annually, respectively, during 2006-2015. Compared with matched controls, age-, sex-, and comorbidity-adjusted SHRs for mortality in patients with nephrotoxin-related kidney failure were 4.2 (95% CI, 3.2 to 5.5) and 1.4 (95% CI, 1.0 to 2.0) for those with and without active malignancy, respectively; for those with urinary tract cancer, SHRs were 2.0 (95% CI, 1.7 to 2.2) and 1.1 (95% CI, 0.9 to 1.2). The corresponding SHRs for transplant wait-listing were 0.19 (95% CI, 0.11 to 0.32) and 0.62 (95% CI, 0.43 to 0.88) for nephrotoxin-related kidney failure cases and 0.28 (95% CI, 0.21 to 0.37) and 0.47 (95% CI, 0.36 to 0.60) for urinary tract cancer cases. Once on the waiting list, access to transplantation did not differ significantly between cases and controls.

CONCLUSIONS

Cancer-related kidney failure is slowly but steadily increasing. Mortality does not appear to be increased among patients without active malignancy at dialysis start, but their access to kidney transplant remains limited.

Sunitinib versus sorafenib for patients with advanced renal cell carcinoma with renal impairment before the immune-oncology therapy era

OBJECTIVES

The efficacy and safety of sunitinib versus sorafenib in patients with advanced renal cell carcinoma with renal impairment remains poorly documented.

PATIENTS AND METHODS

We assessed the efficacy and safety of sunitinib and sorafenib in patients with advanced renal cell carcinoma with an estimated glomerular filtration rate of 15-60 mL/min/1.73 m2 by reviewing the medical records of patients treated at Jichi Medical University Hospital, Japan, between May 2008 and August 2016.

RESULTS

Twenty-seven patients were treated with sunitinib and 14 with sorafenib. Median progression-free survival in sunitinib- and sorafenib-treated patients was comparable, at 6.6 vs 5.8 months, respectively (HR, 1.618; 95% CI, 0.689-3.798; P = 0.2691). Median overall survival was also comparable, at 65.9 vs 58.0 months (HR, 0.985; 95% CI, 0.389-2.479; P = 0.9748). Grade 3 or higher adverse events were significantly more frequent in the sunitinib-treated than sorafenib-treated patients (P = 0.0357). Compared to pre-treatment values, estimated glomerular filtration rate at the discontinuation of treatment was not decreased in either group. In contrast, estimated glomerular filtration rate was decreased on long-term treatment, particularly in previously nephrectomized patients.

CONCLUSIONS

Sunitinib and sorafenib had similar efficacy in patients with advanced renal cell carcinoma and severe renal impairment. Although renal function was not markedly impaired in either group, close attention to decreased renal function may be necessary in previously nephrectomized patients on long-term treatment.

The role of three-dimensional reconstruction in laparoscopic partial nephrectomy for complex renal tumors

BACKGROUND

To evaluate the role of three-dimensional (3D) reconstruction technique in renal function protection and ipsilateral parenchymal mass preserved after laparoscopic partial nephrectomy (LPN) in patients with complex renal tumor (R.E.N.A.L.score ≥ 8).

METHODS

A retrospective study enrolling 49 patients who suffered from RCC and underwent LPN at our center, from October 1, 2017, to October 31, 2018. Twenty-one patients (group A) underwent LPN with the 3D reconstruction technique before surgery, and the other 28 patients (group B) not. Preoperative and postoperative ipsilateral parenchymal mass volume and ipsilateral glomerular filtration rate (GFR) were analyzed 3-5 days prior and 3 months after PN. In order to compare the two groups, Mann-Whitney U test and chi-square tests were performed. The main limitation of this technique is that the volume calculations are partly performed manually.

RESULTS

All patients' median renal score was 10 with no difference between the two groups (P = 0.89), and the median tumor size of the two groups was 3.2 cm (group A) and 3.3 cm (group B) respectively (P = 0.14). In addition, the median warm ischemia time of the two groups was 21 min (group A) and 26 min (group B) (P = 0.003). In group A and group B, the rate of preserved global GFR was 88% and 86% (P = 0.06), preserved ipsilateral GFR was 80% and 77% (P = 0.01), and preserved ipsilateral parenchymal was 84% and 80% (P = 0.03) separately.

CONCLUSION

3D reconstruction technique was a beneficial method for more renal function and more preserved renal parenchymal mass volume after LPN.

TRIAL REGISTRATION

Yantai Yuhuangding Hospital, YHD[2017]212. Registered 1 January 2017 (prospectively registered), http://www.ytyhdyy.com/nav/103.htm .

Outcome Measures Used to Report Kidney Function in Studies Investigating Surgical Management of Kidney Tumours: A Systematic Review

CONTEXT

Most practice decisions relevant to preserving kidney function in patients managed surgically for kidney tumours are driven by observational studies. A wide range of outcome measures are used in these studies, which reduces comparability and increases the risk of reporting bias.

OBJECTIVE

To comprehensively and succinctly describe the outcomes used to evaluate kidney function in studies evaluating surgical management of kidney tumours.

EVIDENCE ACQUISITION

Electronic search of the PubMed database was conducted to identify studies with at least one measure of kidney function in patients managed surgically for kidney tumours, published between January 2000 and September 2017. Abstracts were initially screened for eligibility. Full texts of articles were then evaluated in more detail for inclusion. A narrative synthesis of the evidence was conducted.

EVIDENCE SYNTHESIS

A total of 312 studies, involving 127905 participants, were included in this review. Most were retrospective (n=274) studies and conducted in a single centre (n=264). Overall, 78 unique outcome measures were identified, which were grouped into six outcome categories. Absolute postoperative kidney function (n=187), relative kidney function (n=181), and postoperative chronic kidney disease (n=131) were most frequently reported. Kidney function was predominantly quantified using estimated glomerular filtration rate or creatinine clearance (n=255), most using the modification of diet in renal disease equation (n=182). Only 70 studies provided rationale for specific outcome measures used.

CONCLUSIONS

There is significant variability in the reporting and quantification of kidney function in studies evaluating patients managed surgically for kidney tumours. A standardised approach to measuring and reporting kidney function will increase the effectiveness of outcomes reported and improve relevance of research findings within a clinical context.

PATIENT SUMMARY

Although we know that the removal of a kidney can reduce kidney function, clinical significance of various approaches is a matter of debate. This article demonstrates significant variability in the way kidney function was reported across all studies of patients with kidney cancer undergoing surgery, indicating a need for standardisation.