Trends in renal function after radical nephrectomy: a multicentre analysis

Incidence, risk factors, and significance of 20% decrease from new baseline estimated glomerular filtration rate after radical and partial nephrectomy within 2 years

OBJECTIVES

To evaluate the incidence and risk factors of a 20% decrease from new baseline (NB)-estimated glomerular filtration rate (eGFR) within 2 years after radical nephrectomy (RN) and partial nephrectomy (PN) and to examine the difference in the incidence of end-stage renal disease (ESRD) with or without the 20% decrease.

METHODS

This retrospective study included 238 patients undergoing RN and 369 undergoing PN for cT1a-cT3a renal cancer. The incidence of a 20% decrease from NB-eGFR within 2 years after RN/PN was examined and its potential risk factors including surgery type were assessed by multivariate logistic regression analysis. The development of ESRD was analyzed as an endpoint and its incidence was compared according to the presence or absence of the 20% decrease from NB-eGFR within 2 years.

RESULTS

Overall, the 20% decrease from NB-eGFR within 2 years was observed in 37 patients (6.1%), including 10 (4.2%) and 27 (7.3%) after RN and PN, respectively (p = 0.117). Diabetes mellitus, proteinuria, and perioperative complications were shown to be independent risk factors for the 20% decrease from NB-eGFR, while surgery type was not. During the median follow-up of 65 months, the ESRD-free survival rate at 6 years was 75.5% and 99.6% in patients with and without the 20% decrease from NB-eGFR, respectively (p < 0.001), while no significant difference was observed between patients undergoing RN and PN (98.1% and 98.7%, p = 0.561).

CONCLUSIONS

Because the incidence of ESRD after the 20% decrease from NB-eGFR within 2 years was as high as 24.5% at 6 years, these patients should be followed with utmost care.

Preoperative hydronephrosis is an independent protective factor of renal function decline after nephroureterectomy for upper tract urothelial carcinoma

Objectives

To evaluate the predictive role of pre-nephroureterectomy (NU) hydronephrosis on post-NU renal function (RF) change and preserved eligibility rate for adjuvant therapy in patients with upper tract urothelial carcinoma (UTUC).

Patients and methods

This retrospective study collected data of 1018 patients from the Taiwan UTUC Collaboration Group registry of 26 institutions. The patients were divided into two groups based on the absence or presence of pre-NU hydronephrosis. Estimated glomerular filtration rate (eGFR) was calculated pre- and post-NU respectively. The one month post-NU RF change, chronic kidney disease (CKD) progression, and the preserved eligibility rate for adjuvant therapy were compared for each CKD stage.

Results

404 (39.2%) patients without and 614 (60.8%) patients with pre-NU hydronephrosis were enrolled. The median post-NU change in the eGFR was significantly lower in the hydronephrosis group (-3.84 versus -12.88, p<0.001). Pre-NU hydronephrosis was associated with a lower post-NU CKD progression rate (33.1% versus 50.7%, p< 0.001) and was an independent protective factor for RF decline after covariate adjustment (OR=0.46, p<0.001). Patients with pre-NU hydronephrosis had a higher preserved eligibility rate for either adjuvant cisplatin-based chemotherapy (OR=3.09, 95%CI 1.95-4.69) or immune-oncology therapy (OR=2.31, 95%CI 1.23-4.34).

Conclusion

Pre-NU hydronephrosis is an independent protective predictor for post-NU RF decline, CKD progression, and eligibility for adjuvant therapy. With cautious selection for those unfavorably prognostic, non-metastatic UTUC patients with preoperative hydronephrosis, adjuvant rather than neoadjuvant therapy could be considered due to higher chance of preserving eligibility.

Preoperative versus Postoperative Compensation of the Contralateral Normal Kidney in Patients Treated with Radical Nephrectomy for Renal Cell Carcinoma

BACKGROUND

We sought to identify the factors affecting renal compensatory processes that occur preoperatively as well as postoperatively in patients treated with radical nephrectomy (RNx) for renal cell carcinoma (RCC).

METHODS

We retrospectively reviewed the records of 906 patients treated with RNx for RCC. We defined the early compensatory process (process 1) as compensatory adaptation of the contralateral normal kidney (CNK) before RNx. We defined the late compensatory process (process 2) as compensatory adaptation of the CNK after RNx. Total compensation was defined as the combination of these two processes. Multivariable logistic regression analyses were used to identify significant factors associated with processes 1, 2 and total compensation.

RESULTS

Mean preoperative, 1-week, and 5-year postoperative estimated glomerular filtration rates (eGFR) were 84.5, 57.6 and 63.7 mL/min/1.73 m2, respectively. Female sex (p < 0.001), lower body mass index (BMI) (p < 0.001), absence of hypertension (p = 0.019), lower preoperative eGFR (p < 0.001), larger tumor volume (p < 0.001), and larger CNK volume (p < 0.001) were significantly associated with process 1. Younger age (p = 0.019), higher BMI (p < 0.001), and absence of diabetes mellitus (DM) (p = 0.033) were significantly associated with process 2. Female sex (p < 0.001), younger age (p < 0.001), absence of DM (p = 0.002), lower preoperative eGFR (p < 0.001), and larger tumor (p = 0.001) and CNK volumes (p < 0.001) were significantly associated with total compensation.

CONCLUSIONS

Different factors affected each compensatory process. Process 1 made a greater contribution to the entire renal compensatory process than process 2.

Development and Validation of a Nomogram Model to Predict Acute Kidney Disease After Nephrectomy in Patients with Renal Cell Carcinoma

Purpose

To develop and validate a nomogram model to predict the occurrence of acute kidney disease (AKD) after nephrectomy.

Patients and Methods

A retrospective cohort including 378 patients with renal cell carcinoma (RCC) who had undergone radical or partial nephrectomy between March 2013 and December 2017 at the First Affiliated Hospital of Zhengzhou University was analyzed. Of these, patients who had undergone surgery in an earlier period of time formed the training cohort (n=265) for nomogram development, and those who had undergone surgery thereafter formed the validation cohort (n=113) to confirm the model's performance. The incidence rate of AKD was measured. Univariate and multivariate logistics regression analysis was used to estimate the independent risk factors associated with AKD. The independent risk factors were incorporated into the nomogram. The accuracy and utility of the nomogram were evaluated by calibration curve and decision curve analysis, respectively.

Results

Overall, AKD occurred in 27.5% and 28.3% of patients in the training and validation cohorts, separately. The final nomogram included surgery approach, Charlson comorbidity index (CCI), and the decrement of eGFR. This model achieved good concordance indexes of 0.78 (95% CI=0.71-0.84) and 0.76 (95% CI=0.67-0.86) in the training and validation cohorts, respectively. The calibration curves and decision curve analysis (DCA) demonstrated the accuracy and the clinical usefulness of the proposed nomogram, separately.

Conclusion

The nomogram accurately predicts AKD after nephrectomy in patients with RCC. The risk for patients' progress into AKD can be determined, which is useful in guiding clinical decisions.

Remaining kidney volume indexed to weight as a strong predictor of estimated glomerular filtration rate at 1 year and mid-term renal function after living-donor nephrectomy - a retrospective observational study

The donors' estimated glomerular filtration rate (eGFR) after living nephrectomy has been a concern, particularly in donors with smaller kindeys. Therefore, we developed this retrospective observational study in 195 donors to determine the ability remaining kidney volume indexed to weight (RKV/W) to predict eGFR at 1 year through multivariate linear regression and to explore this relationship between annual eGFR change from 1 to 4 years postdonation evaluated by a linear mixed model. Comparing RKV/W tertiles (T1, T2, T3), RKV/W was a good predictor of 1-year eGFR which was significantly better in T3 donors. Gender, predonation eGFR, and RKV/W were independent predictors of eGFR at 1-year. In a subgroup with predonation eGFR < 90mL/min/1.73 m² , a significant prediction of eGFR < 60mL/min/1.73 m² was detected in males with RKV/W ≤ 2.51cm³ /kg. Annual eGFR (ml/min/year) change from 1 to 4 years was + 0.77. RKV/W divided by tertiles (T1-T3) was the only significant predictor: T2 and T3 donors had an annual eGFR improvement opposing to T1. RKV/W was a good predictor of eGFR at 1 year, independently from predonation eGFR. A higher RKV/W was associated with improved eGFR at 1 year. A decline in eGFR on the four years after surgery was only noticeable in donors with RKV/W ≤ 2.13cm³ /kg.

Impact of short warm ischemic time on longitudinal kidney function and survival rate after partial nephrectomy for renal cell carcinoma in patients with pre-existing chronic kidney disease stage III: A multi-institutional propensity score-matched study

PURPOSE

It remains unclear whether a short warm ischemic time (WIT) improves long-term renal function after partial nephrectomy (PN) for patients with pre-existing chronic kidney disease (CKD). We evaluated renal function after PN according to WIT duration in patients with stage III CKD.

MATERIALS AND METHODS

We identified 277 patients with stage III CKD who underwent PN during 2004-2017. Propensity score matching was used to created two matched groups of patients: Group A (WIT of <25 min) and Group B (WIT of ≥25 min). The outcomes of interest were longitudinal kidney function change, new-onset stage IV CKD (eGFR <30 mL/min/1.73 m²) and overall survival.

RESULTS

The two matched groups contained 85 patients each. The median follow-up durations were 49 months in Group A and 42 months in Group B. The median pre-treatment eGFRs were 52.4 mL/min/1.73 m² in Group A and 52.6 mL/min/1.73 m² in Group B. There were no differences in kidney function between the two groups throughout the follow-up period (P > 0.05). The 5-year rates of new-onset stage IV CKD were not significantly different between Group A and Group B (8.2% vs. 7.1%), with no significant difference in the risk of developing stage IV CKD in Group A (vs. group B, hazard ratio: 0.527, 95% confidence interval: 0.183-1.521; P = 0.236). The 5-year overall survival rates were 90.3% for Group A and 96.2% for Group B (P = 0.549).

CONCLUSIONS

A short WIT was not associated with better postoperative kidney function or survival after PN in patients with stage III CKD.

The effect of renal function change on renal cell carcinoma patients with tumor thrombus after nephrectomy and thrombectomy: a large Chinese center experience

Background

To explore the influencing factors of perioperative renal function change and their relationship with prognosis on renal cell carcinoma (RCC) patients with tumor thrombus after nephrectomy and thrombectomy.

Methods

The clinical and pathological data of 135 patients with RCC and tumor thrombus, who underwent nephrectomy and thrombectomy at Peking University Third Hospital from May 2015 to July 2018, was retrospectively analyzed. Absolute change in estimated glomerular filtration rate (eGFR) (ACE) and percent change in eGFR (PCE) were calculated by preoperative and postoperative renal function. Linear regression analysis was used to explore the influencing factors of ACE and PCE, and logistic regression analysis was used to explore the influencing factors of worse postoperative renal function [eGFR≤60 mL/(min × 1.73 m^2)]. Cancer-specific survival (CSS) was estimated by Kaplan-Meier method and multivariate Cox regression, which were used to explore the effect of ACE and PCE on prognosis.

Results

Of all the 135 patients, 101 patients (74.8%) were male and 34 patients (25.2%) were female. The mean preoperative eGFR was 73.9 ± 21.8 mL/(min × 1.73 m^2) and postoperative eGFR was 69.5 ± 25.2 mL/(min × 1.73 m^2). In multivariate linear regression analysis, preoperative eGFR (P < 0.001) and pathological type (P = 0.038) were significant predictive factors of ACE. In aspect of PCE, preoperative eGFR (P < 0.001) and pathological type (P = 0.002) were significant predictors. In multivariate logistic regression analysis, preoperative eGFR (P = 0.016) was the only risk factor of predicting worse postoperative renal function. During follow-up, 22 patients (16.3%) were dead due to RCC. According to ROC analysis, the cut off value of ACE and PCE was 13.9 and 0.16, respectively. ACE> 13.9 and PCE > 0.16 indicated worse CSS (P = 0.006 and P = 0.047, respectively). However, in multivariate Cox regression analysis of several related factors, perinephric tissues invasion (P = 0.001), sarcomatoid differentiation (P = 0.001) and ACE> 13.9 (P = 0.002) were significant prognostic factors for CSS. PCE > 0.16 seemed to be not (P = 0.055).

Conclusion

We explored several clinicopathological risk factors of predicting renal function change and their relationship with prognosis of RCC patients with tumor thrombus after nephrectomy and thrombectomy. The renal function change, which was associated with preoperative eGFR and pathological type, was prognostic risk factor for CSS and ACE> 13.9 indicated the worse prognosis.

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.

Comparison of long-term kidney functions after radical nephrectomy and simple nephrectomy

Objective

To determine if there is a difference in proceeding to CKD between patients who had undergone radical nephrectomy (RN) and simple nephrectomy (SN) for different indications by comparing the short- and long-term renal function.

Materials and Methods

We retrospectively analyzed the records of all patients who underwent nephrectomy (either for malign or benign indications) in our clinic between January 2007 and September 2017. The patients were divided into 2 groups according the type of surgery: 1) Radical nephrectomy Group, 2) Simple Nephrectomy Group. Renal function was evaluated with Glomerular Filtration Rate (GFR) calculated using the MDRD formula.

Results

A total of 276 patients were included in the study. There were 202 patients in RN Group and 74 patients in SN Group. The mean age of the patients in RN Group and SN Group were age 59,2 ± 11,5 and 49,9 ± 15,1 years, respectively (p = 0.001). GFR levels of patients in RN Group versus SN Group were as follows: Preoperative period: 84.9 vs. 81 mL/min/1.73 m²; postoperative 1st day: 60.5 vs. 84.4 mL/min/1.73 m², postoperative 1st month 58.9 vs. 76 mL/min/1.73 m², postoperative 1st year: 59.5 vs. 74.1 mL/min/1.73 m²; at last control 60.3 and 76.1 mL/min/1.73 m². While preoperative GFR was found to be similar in two groups (p = 0.26), postoperative GFR values were found to be significantly lower in Group RN (p < 0.001). In comparison of the decrease in GFR in two groups at last follow-up, significantly higher decrease was observed in RN Group, 29% vs. 6%, (p < 0.05).

Conclusion

The decrease in GFR exists more common and intensive after RN compared to SN. In long-term, compensation mechanisms that develop after sudden nephron loss like radical nephrectomy deteriorates kidney function more than gradual nephron loss as in benign etiologies which indicates simple nephrectomy.

Organ-sparing procedures in GU cancer: part 1-organ-sparing procedures in renal and adrenal tumors: a systematic review

PURPOSE

Organ-sparing surgery (OSS) for the kidney and adrenals has emerged as the need for preservation of function is paramount in patients with poor functional reserve. As reports increasingly showed that oncological outcomes were equivalent to radical excision, elective OSS became a viable alternative in patients with otherwise normal reserve. In this review, we summarize the current knowledge of OSS for adrenal and renal tumors.

MATERIALS AND METHODS

PubMed, Web of Science and Cochrane Library Central Search were searched for recently published articles up to December 2017. The following keywords were used; "partial adrenalectomy", "adrenal sparing", "partial nephrectomy", "nephron sparing", "kidney/renal cancer".

RESULTS

Partial adrenalectomy became an attractive alternative to total adrenalectomy avoiding adrenal insufficiency. Both minimally invasive surgery and ablative techniques were increasingly reported for adrenal OSS with adequate residual adrenal function and excellent oncological outcome. Radical nephrectomy remained for many years as the gold standard of treatment for organ-confined renal cell carcinoma. As the need to reduce the impact on renal function, more conservative approaches were utilized. Soon, the non-inferiority of nephron-sparing surgery to that of radical excision became evident and elective partial nephrectomy was gaining ground as the standard of care for small renal masses in patients with normal contralateral kidneys.

CONCLUSIONS

Herein, we present a comprehensive review of the current status of OSS in renal and adrenal tumors.

Partial versus Radical Nephrectomy for T1-T2 Renal Cell Carcinoma in Patients with Chronic Kidney Disease Stage III: a Multiinstitutional Analysis of Kidney Function and Survival Rate

BACKGROUND

To examine survival rates and renal function after partial nephrectomy (PN) and radical nephrectomy (RN) in patients with chronic kidney disease (CKD).

METHODS

We studied 4,332 patients who underwent PN or RN for pathological T1a-T2N0M0 renal cell carcinoma from 1988 to 2014. Patients were divided into two subgroups of CKD stage I-II and stage III. Kidney function, and survival outcomes were compared between groups.

RESULTS

We included 1,756 patients with CKD I-II and 276 patients with CKD III in the final pair-matched analysis. Kidney function was significantly better preserved in the PN than in the RN group among all patients. However, the beneficial effect of PN on kidney function gradually disappeared over time in CKD III patients. The 5-year overall survival (OS) rates after PN and RN differed in patients with CKD I-II disease (99.4% vs. 96.5%, respectively, P = 0.015). The 5-year OS rates after surgery were not affected by mode of nephrectomy in CKD III patients (97.8% vs. 93.5%, P = 0.103). The 5-year cancer-specific survival rates did not differ between treatment groups in all CKD stage. Cox hazard analysis showed that the operative method was a significant factor for OS in CKD I-II patients (hazard ratio [HR], 0.320; confidence interval [CI], 0.122-0.840; P = 0.021). However, PN was not beneficial in terms of OS in CKD III patients (HR, 0.395; CI, 0.086-1.172; P = 0.117).

CONCLUSION

PN is associated with a higher OS rate and better kidney function in patients with preoperative CKD stage I and II, but not in those with CKD stage III.

Clinical significance of serum neutrophil gelatinase-associated lipocalin in the early diagnosis of renal function deterioration after radical nephrectomy

Objectives The standard metrics used to monitor the progression of acute kidney injury (AKI) include markers such as serum creatinine, blood urea nitrogen, and estimated glomerular filtration rate (eGFR). Moreover, neutrophil gelatinase-associated lipocalin (NGAL) expression has been reported to modulate oxidative stress. Methods We aimed to evaluate the usefulness of serum NGAL levels for monitoring renal function after radical nephrectomy (RN). We prospectively collected data from 30 patients who underwent RN. We analyzed serum NGAL and creatinine at 6 time points: preoperative day 1, right after surgery, 6 hours after surgery, postoperative day (POD) 1, POD 3, and POD 5. We compared these measurements according to the eGFR values (classified as chronic kidney disease stage III; CKD III or not) using data obtained 3 months after surgery. Results The mean age was 65.5 years (range, 45–77 years), and the male-to-female ratio was 2:1. At the last follow-up examination, there were 12 patients (40%) with CKD III. Using receiver operating characteristic analysis, we found that serum creatinine on POD 5 (area under the curve [AUC], 0.887; P = 0.000) and NGAL at 6 hours after LRN (AUC, 0.743, P = 0.026) were significant predictors of CKD III. The development of CKD III after LRN was associated with the serum creatinine level on POD 5 and the NGAL at 6 hours after surgery. Conclusions Compared to serum creatinine, serum NGAL enabled earlier prediction of postoperative CKD III. Therefore, serum NGAL measured 6 hours after surgery could be a useful marker for managing patients after RN.

The Effect of Patient and Surgical Characteristics on Renal Function After Partial Nephrectomy

BACKGROUND

The purpose of the study was to identify patient and disease characteristics that have an adverse effect on renal function after partial nephrectomy.

PATIENTS AND METHODS

We conducted a retrospective review of 387 patients who underwent partial nephrectomy for renal tumors between 2006 and 2014. A line plot with a locally weighted scatterplot smoothing was generated to visually assess renal function over time. Univariable and multivariable longitudinal regression analyses incorporated a random intercept and slope to evaluate the association between patient and disease characteristics with renal function after surgery.

RESULTS

Median age was 60 years and most patients were male (255 patients [65.9%]) and white (343 patients [88.6%]). In univariable analysis, advanced age at surgery, larger tumor size, male sex, longer ischemia time, history of smoking, and hypertension were significantly associated with lower preoperative estimated glomerular filtration rate (eGFR). In multivariable analysis, independent predictors of reduced renal function after surgery included advanced age, lower preoperative eGFR, and longer ischemia time. Length of time from surgery was strongly associated with improvement in renal function among all patients.

CONCLUSION

Independent predictors of postoperative decline in renal function include advanced age, lower preoperative eGFR, and longer ischemia time. A substantial number of subjects had recovery in renal function over time after surgery, which continued past the 12-month mark. These findings suggest that patients who undergo partial nephrectomy can experience long-term improvement in renal function. This improvement is most pronounced among younger patients with higher preoperative eGFR.

Radical versus partial nephrectomy, chronic kidney disease progression and mortality in US veterans

Background

Partial nephrectomy is considered the preferred care for localized kidney tumors and may yield better patient and kidney survival and similar oncological outcomes compared with radical nephrectomy. We sought to reexamine these hypotheses in a large nationally representative cohort of US veterans who underwent radical or partial nephrectomy.

Methods

We identified 7073 US veterans who had a partial or radical nephrectomy between 2004 and 2013. We collected data on estimated glomerular filtration rate (eGFR) prior to admission for nephrectomy surgery, immediately after surgery and 180 days postsurgery. We evaluated the association of nephrectomy type and eGFR at different time points with long-term mortality risk in adjusted survival models.

Results

Patients who underwent radical (compared to partial) nephrectomy had a 2-fold greater decline in eGFR (-21.8 ± 17.7 versus -10.3 ± 17.4 mL/min/1.73 m2) immediately after surgery. This larger drop in eGFR resulted in a larger proportion of radical nephrectomy patients having an eGFR <60 mL/min/1.73 m2 at ≥180 days postsurgery. Radical (compared to partial) nephrectomy patients also exhibited a 2.2-fold higher mortality [adjusted death hazard ratio 2.21 (95% confidence interval 1.91-2.55)]. Low eGFRs prior to surgery and 180 days postsurgery were associated with higher risk of postnephrectomy death.

Conclusions

Worse postnephrectomy kidney function and higher mortality were observed with radical nephrectomy, and a low presurgical eGFR and a greater decrease in eGFR postsurgery were associated with worse mortality irrespective of the type of nephrectomy. Additional studies are needed to examine predictors of postnephrectomy outcomes.

Long-Term Renal Function Recovery following Radical Nephrectomy for Kidney Cancer: Results from a Multicenter Confirmatory Study

PURPOSE

We sought to confirm the findings from a previous single institution study of 572 patients from Memorial Sloan Kettering Cancer Center in which we found that 49% of patients recovered to the preoperative estimated glomerular filtration rate within 2 years following radical nephrectomy for renal cell carcinoma.

MATERIALS AND METHODS

A multicenter retrospective study was performed in 1,928 patients using data contributed from 3 independent centers. The outcome of interest was postoperative recovery to the preoperative estimated glomerular filtration rate. Data were analyzed using cumulative incidence and competing risks regression with death from any cause treated as a competing event.

RESULTS

This study demonstrated that 45% of patients had recovered to the preoperative estimated glomerular filtration rate by 2 years following radical nephrectomy. Furthermore, this study confirmed that recovery of renal function differed according to preoperative renal function such that patients with a lower preoperative estimated glomerular filtration rate had an increased chance of recovery. This study also suggested that larger tumor size and female gender were significantly associated with an increased chance of renal function recovery.

CONCLUSIONS

In this multicenter retrospective study we confirmed that in the long term a large proportion of patients recover to preoperative renal function following radical nephrectomy for kidney tumors. Recovery is more likely among those with a lower preoperative estimated glomerular filtration rate.

Management of Small Renal Masses: American Society of Clinical Oncology Clinical Practice Guideline

Purpose To provide recommendations for the management options for patients with small renal masses (SRMs). Methods By using a literature search and prospectively defined study selection, we sought systematic reviews, meta-analyses, randomized clinical trials, prospective comparative observational studies, and retrospective studies published from 2000 through 2015. Outcomes included recurrence-free survival, disease-specific survival, and overall survival. Results Eighty-three studies, including 20 systematic reviews and 63 primary studies, met the eligibility criteria and form the evidentiary basis for the guideline recommendations. Recommendations On the basis of tumor-specific findings and competing risks of mortality, all patients with an SRM should be considered for a biopsy when the results may alter management. Active surveillance should be an initial management option for patients who have significant comorbidities and limited life expectancy. Partial nephrectomy (PN) for SRMs is the standard treatment that should be offered to all patients for whom an intervention is indicated and who possess a tumor that is amenable to this approach. Percutaneous thermal ablation should be considered an option if complete ablation can reliably be achieved. Radical nephrectomy for SRMs should only be reserved for patients who possess a tumor of significant complexity that is not amenable to PN or for whom PN may result in unacceptable morbidity even when performed at centers with expertise. Referral to a nephrologist should be considered if chronic kidney disease (estimated glomerular filtration rate < 45 mL/min/1.73 m²) or progressive chronic kidney disease occurs after treatment, especially if associated with proteinuria.

Influence of Tyrosine Kinase Inhibitors on Hypertension and Nephrotoxicity in Metastatic Renal Cell Cancer Patients

Renal cell carcinoma (RCC) is one of the most common kidney malignancies. An upgraded comprehension of the molecular biology implicated in the development of cancer has stimulated an increase in research and development of innovative antitumor therapies. The aim of the study was to analyze the medical literature for hypertension and renal toxicities as the adverse events of the vascular endothelial growth factor (VEGF) signaling pathway inhibitor (anti-VEGF) therapy. Relevant studies were identified in PubMed and ClinicalTrials.gov databases. Eligible studies were phase III and IV prospective clinical trials, meta-analyses and retrospective studies that had described events of hypertension or nephrotoxicity for patients who received anti-VEGF therapy. A total of 48 studies were included in the systematic review. The incidence of any grade hypertension ranged from 17% to 49.6%. Proteinuria and increased creatinine levels were ascertained in 8% to 73% and 5% to 65.6% of patients, respectively. These adverse events are most often mild in severity but may sometimes lead to treatment discontinuation. Nephrotoxicity and hypertension are related to multiple mechanisms; however, one of the main disturbances in those patients is VEGF inhibition. There is a significant risk of developing hypertension and renal dysfunction among patients receiving anti-VEGF treatment; however, there is also some evidence that these side effects may be used as biomarkers of response to antiangiogenic agents.

More than a decade after live donor nephrectomy: a prospective cohort study

Previously reported short-term results after live kidney donation show no negative consequences for the donor. The incidence of new-onset morbidity takes years to emerge, making it highly likely that this will be missed during short-term follow-up. Therefore, evidence on long-term outcome is essential. A 10-year follow-up on renal function, hypertension, quality of life (QOL), fatigue, and survival was performed of a prospective cohort of 100 donors. After a median follow-up time of 10 years, clinical data were available for 97 donors and QOL data for 74 donors. Nine donors died during follow-up of unrelated causes to donation, and one donor was lost to follow-up. There was a significant decrease in kidney function of 12.9 ml/min (P < 0.001) at follow-up. QOL showed significant clinically relevant decreases of 10-year follow-up scores in SF-36 dimensions of physical function (P < 0.001), bodily pain (P = 0.001), and general health (P < 0.001). MFI-20 scores were significantly higher for general fatigue (P < 0.001), physical fatigue (P < 0.001), reduced activity (P = 0.019), and reduced motivation (P = 0.030). New-onset hypertension was present in 25.6% of the donors. Donor outcomes are excellent 10 years post-donation. Kidney function appears stable, and hypertension does not seem to occur more frequently compared to the general population.

Comparison of preoperative adaptive enlargement of the contralateral normal kidney in patients nephrectomized for benign non-functioning kidney versus renal cell carcinoma

OBJECTIVES

To investigate the potential effects of preoperative volumetric compensation of the contralateral normal kidney on renal function after simple nephrectomy or radical nephrectomy.

METHODS

A total of 306 patients (80 simple nephrectomy patients and 226 radical nephrectomy patients) with 1:3 propensity score matching were included between October 1996 and December 2013. Preoperative three-dimensional kidney volume was estimated from computed tomography images using a specialized volumetric program. Glomerular filtration rate assessed using the Chronic Kidney Disease Epidemiology Collaboration equations was checked preoperatively, 1 week, 3 months and 1 year after nephrectomy.

RESULTS

Preoperative mean Chronic Kidney Disease Epidemiology Collaboration glomerular filtration rate was 76.5 mL/min/1.73 m(2) in the simple nephrectomy group and 89.2 mL/min/1.73 m(2) in the radical nephrectomy group. In simple nephrectomy patients, mean Chronic Kidney Disease Epidemiology Collaboration glomerular filtration rate showed a stable pattern up to 3 months (75.5 mL/min/1.73 m(2) at 7 days and 76.2 mL/min/1.73 m(2) at 3 months), and decreased slightly to 72.6 mL/min/1.73 m(2) at 1 year. However, in radical nephrectomy patients, mean Chronic Kidney Disease Epidemiology Collaboration glomerular filtration rate decreased immediately to 63.4 mL/min/1.73 m(2) at 7 days after surgery, and then increased gradually to 64.6 mL/min/1.73 m(2) at 3 months and 65.9 mL/min/1.73 m(2) at 1 year. Preoperative mean contralateral normal kidney volume was 225.7 mL in the simple nephrectomy group and 180.1 mL in the radical nephrectomy group (P < 0.001). The contralateral normal kidney volume to total normal kidney volume ratio was 0.74 in the simple nephrectomy group and 0.51 in the radical nephrectomy group (P < 0.001).

CONCLUSIONS

Preoperative volumetric compensation of the contralateral normal kidney is important to maintain postoperative renal function in patients undergoing nephrectomy.

Recovery of renal function after radical nephrectomy and risk factors for postoperative severe renal impairment: A Japanese multicenter longitudinal study

OBJECTIVES

To investigate longitudinal changes in renal function after radical nephrectomy, and to explore risk factors of postoperative severe renal impairment in a Japanese multicenter cohort.

METHODS

The present retrospective study included 701 patients who had no metastasis, end-stage kidney disease or bilateral kidney cancer, who underwent radical nephrectomy and who were followed up for at least 1 year. The longitudinal change in postoperative renal function during a 10-year follow-up period was evaluated according to the presence or absence of potential risk factors including greater age, chronic kidney disease, hypertension, diabetes mellitus and cardiovascular disease. A slope of annual change in estimated glomerular filtration rate was analyzed using a linear mixed model. Associations between the potential risk factors and a >50% estimated glomerular filtration rate decrease were evaluated using a multivariate Cox regression model.

RESULTS

Overall, the postoperative estimated glomerular filtration rate recovered over time with a significant positive slope of 0.34 mL/min/1.73 m(2)/year. Renal function did not tend to recover in patients with chronic kidney disease, hypertension, diabetes mellitus or cardiovascular disease. The multivariate analysis showed that greater age and diabetes mellitus were independent risk factors for severe renal impairment.

CONCLUSIONS

Overall, patients who had deteriorated renal function immediately after radical nephrectomy recovered over time. However, patients with chronic kidney disease, hypertension, diabetes mellitus and cardiovascular disease did not tend to recover renal function postoperatively. Greater age and diabetes mellitus were independent risk factors for a >50% decrease in estimated glomerular filtration rate.

Kidney disease progression in patients of upper tract urothelial carcinoma following unilateral radical nephroureterectomy

OBJECTIVES

To compare the renal outcomes in patients of unilateral renal cell carcinoma (RCC) with upper tract urothelial carcinoma (UTUC) following surgical resection of the tumor-bearing kidney, and to investigate the potential predictors in renal function decline.

PATIENTS AND METHODS

In this retrospective cohort study, 319 RCC patients undergoing radical nephrectomy (RN) and 297 UTUC patients undergoing radical nephroureterectomy were recruited from a tertiary medical center between 2001 and 2010. Demographic data, co-morbidity, smoking habit, baseline estimated glomerular filtration rate (eGFR) calculated by chronic kidney disease-epidemiology equation, as well as tumor staging of RCC and UTUC, were recorded. The primary endpoint was serum creatinine doubling and/or end-stage renal disease (ESRD) necessitating long-term dialysis. Cox proportional hazard model and Fine and Gray's competing risk regression accounting for death were used to model renal outcome.

RESULTS

UTUC patients had a higher incidence rate of renal function deterioration than RCC patients did (15.01 vs. 2.68 per 100 person-years, p<0.001). In Cox proportional hazard model and Fine and Gray's competing risk regression, UTUC was significantly associated with increased risk of creatinine doubling and/or ESRD necessitating dialysis (hazard ratio, 3.13; 95% confidence interval, 2.01-4.87) as compared to RCC following unilateral RN. Nevertheless, our study is observational in nature and cannot prove causality.

CONCLUSIONS

UTUC per se is strongly associated with kidney disease progression as compared to RCC following unilateral nephrectomy. Further studies are needed to elucidate this association.

Factors Associated with Recovery of Renal Function following Radical Nephrectomy for Kidney Neoplasms

BACKGROUND AND OBJECTIVES

Partial nephrectomy or radical nephrectomy is the standard of care for patients with kidney neoplasms, but surgery may result in loss of renal function. We sought to identify patient characteristics associated with renal functional recovery following radical nephrectomy.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We performed a retrospective study among 572 patients with kidney neoplasms who underwent RN between 2006 and 2013. The primary endpoint was recovery of postoperative eGFR to the preoperative level. We plotted the trajectory of each patient's eGFR from their first postoperative visit up to 3 years after surgery. Cumulative incidence and competing risks regression estimated associations between patient and clinical characteristics and eGFR recovery, stratified by preoperative eGFR.

RESULTS

Median age was 61.5 years; 68% of patients were male, and 89% were white. Overall, eGFR increased over time following an initial postoperative decrease. Median postoperative follow-up among survivors was 10.8 (minimum, 0.03; maximum, 36.0) months; during follow-up, 263 patients achieved eGFR recovery. Median time to eGFR recovery was 25.3 months. Two-year cumulative incidence of eGFR recovery was 49% overall and 44% and 58% among those with preoperative eGFR≥60 and <60 ml/min per 1.73 m(2), respectively (P<0.001). On multivariable analysis, younger age at surgery and female sex were significantly associated with a higher chance of eGFR recovery among patients with preoperative eGFR<60 ml/min per 1.73 m(2). Among patients with preoperative eGFR≥60 ml/min per 1.73 m(2), hypertension was significantly associated with a lower chance of eGFR recovery, whereas increased tumor size was significantly associated with a higher chance of eGFR recovery.

CONCLUSIONS

Overall, almost half of the patients in this study recovered to their preoperative eGFR by 2 years following surgery. Distributions of preoperative risk factors differed by preoperative eGFR, leading to distinct factors that were significantly associated with chance of eGFR recovery.

Compensatory Structural and Functional Adaptation after Radical Nephrectomy for Renal Cell Carcinoma According to Preoperative Stage of Chronic Kidney Disease

PURPOSE

We investigated structural hypertrophy and functional hyperfiltration as compensatory adaptations after radical nephrectomy in patients with renal cell carcinoma according to the preoperative chronic kidney disease stage.

MATERIALS AND METHODS

We retrospectively identified 543 patients who underwent radical nephrectomy for renal cell carcinoma between 1997 and 2012. Patients were classified according to preoperative glomerular filtration rate as no chronic kidney disease--glomerular filtration rate 90 ml/minute/1.73 m(2) or greater (230, 42.4%), chronic kidney disease stage II--glomerular filtration rate 60 to less than 90 ml/minute/1.73 m(2) (227, 41.8%) and chronic kidney disease stage III--glomerular filtration rate 30 to less than 60 ml/minute/1.73 m(2) (86, 15.8%). Computerized tomography performed within 2 months before surgery and 1 year after surgery was used to assess functional renal volume for measuring the degree of hypertrophy of the remnant kidney, and the preoperative and postoperative glomerular filtration rate per unit volume of functional renal volume was used to calculate the degree of hyperfiltration.

RESULTS

Among all patients (mean age 56.0 years) mean preoperative glomerular filtration rate, functional renal volume and glomerular filtration rate/functional renal volume were 83.2 ml/minute/1.73 m(2), 340.6 cm(3) and 0.25 ml/minute/1.73 m(2)/cm(3), respectively. The percent reduction in glomerular filtration rate was statistically significant according to chronic kidney disease stage (no chronic kidney disease 31.2% vs stage II 26.5% vs stage III 12.8%, p <0.001). However, the degree of hypertrophic functional renal volume in the remnant kidney was not statistically significant (no chronic kidney disease 18.5% vs stage II 17.3% vs stage III 16.5%, p=0.250). The change in glomerular filtration rate/functional renal volume was statistically significant (no chronic kidney disease 18.5% vs stage II 20.1% vs stage III 45.9%, p <0.001). Factors that increased glomerular filtration rate/functional renal volume above the mean value were body mass index (p=0.012), diabetes mellitus (p=0.023), hypertension (p=0.015) and chronic kidney disease stage (p <0.001).

CONCLUSIONS

Patients with a lower preoperative glomerular filtration rate had a smaller reduction in postoperative renal function than those with a higher preoperative glomerular filtration rate due to greater degrees of functional hyperfiltration.

Renal functional outcomes after surgery for renal cortical tumors

Historically, radical nephrectomy represented the gold standard for the treatment of small (≤ 4cm) as well as larger renal masses. Recently, for small renal masses, the risk of ensuing chronic kidney disease and end stage renal disease has largely favored nephron-sparing surgical techniques, mainly partial nephrectomy. In this review, we surveyed the literature on renal functional outcomes after partial nephrectomy for renal tumors. The largest randomized control trial comparing radical and partial nephrectomy failed to show a survival benefit for partial nephrectomy. With regards to overall survival, surgically induced chronic kidney disease (GFR < 60 ml/min/ 1.73m²) caused by nephrectomy might not be as deleterious as medically induced chronic kidney disease. In evaluating patients who underwent donor nephrectomy, transplant literature further validates that surgically induced reductions in GFR may not affect patient survival, unlike medically induced GFR declines. Yet, because patients who present with a renal mass tend to be elderly with multiple comorbidities, many develop a mixed picture of medically, and surgically-induced renal disease after extirpative renal surgery. In this population, we believe that nephron sparing surgery optimizes oncological control while protecting renal function.

Who really benefits from nephron-sparing surgery?

OBJECTIVE

To analyze the influence of preoperative renal function on postoperative renal outcomes after radical nephrectomy (RN) and nephron-sparing surgery (NSS) for malignancy in patients stratified according to preoperative chronic kidney disease (CKD) stage and surgical extent (NSS vs RN).

PATIENTS AND METHODS

Retrospective review of patients undergoing renal surgery for localized renal masses stratified by surgical extent and preoperative CKD stage based on glomerular filtration rate (GFR) level: stage I (>90 mL/min/1.73 m(2)), stage II (60-89 mL/min/1.73 m(2)), and stage III (30-59 mL/min/1.73 m(2)). Survival analysis for significant renal impairment was based on freedom from the development of new-onset GFR <30 or <45 mL/min/1.73 m(2).

RESULTS

A total of 1306 patients were included in the analysis with preoperative CKD stage I (27.9%), II (52.1%), and III (20.1%); 41.3% and 58.7% underwent NSS and RN, respectively. NSS was associated with a lower annual rate of GFR decline in preoperative CKD stage-I (P = .028) and stage-II patients (P = .018), but not in CKD stage-III patients (P = .753). Overall, 5.0% and 15.0% developed new-onset GFR <30 mL/min/1.73 m(2) and <45 mL/min/1.73 m(2), respectively. There was no difference in the probability of developing significant renal impairment between NSS and RN in CKD stage-I or -III patients, whereas only in CKD stage-II patients was the surgical extent independently associated with development of significant renal impairment (RN: odds ratio, 9.0; P = .042 for GFR <30 mL/min/1.73 m(2) and odds ratio, 2.3; P = .003 for GFR <45 mL/min/1.73 m(2)).

CONCLUSION

Compared with RN, NSS is associated with a lower rate of GFR decline for preoperative CKD stage-I and -II patients, but only CKD stage-II patients demonstrated a decreased risk of developing significant renal impairment.

Overall survival and renal function after partial and radical nephrectomy among older patients with localised renal cell carcinoma: a propensity-matched multicentre study

BACKGROUND

This study aimed to evaluate the overall survival (OS) rate and renal function after radical nephrectomy (RN) and partial nephrectomy (PN) in patients aged ⩾65years.

METHODS

Patients who underwent RN (n=622) or PN (n=622) for renal cell carcinoma (pT1N0M0) between 1999 and 2011 were propensity-score matched in our multicentre database. To investigate the relative effect of PN on OS according to age, we divided the patients into two age subgroups (<65 and ⩾65years). The 5-year OS rates and probabilities of freedom from chronic kidney disease (CKD III or IV) were estimated using the Kaplan-Meier method and separate Cox proportional hazards models.

RESULTS

The 5-year OS rates after surgery were 94.7% for PN and 91.9% for RN in the older patients (P=0.698). The corresponding rates in the younger patients were 99.7% for PN and 96.3% for RN (P=0.015). In separate Cox hazards models for OS, the older patients who underwent PN were not significantly different from their RN-treated counterparts (hazard ratio (HR): 0.960; 95% confidence interval (CI): 0.277-2.321, P=0.797). Kidney function was significantly better preserved after PN than after RN at all ages. However, stage IV CKD in the older patients did not occur more frequently in the RN arm than in the PN arm.

CONCLUSIONS

Although PN was associated with improved renal function compared with RN, it did not confer a benefit of higher survival rate in elderly patients (⩾65yearsold).