Can we predict which patients will evolve to chronic kidney disease after nephrectomy for cortical renal tumors?

Early and late adverse renal effects after potentially nephrotoxic treatment for childhood cancer

BACKGROUND

Improvements in diagnostics and treatment for paediatric malignancies resulted in a major increase in survival. However, childhood cancer survivors (CCS) are at risk of developing adverse effects caused by multimodal treatment for their malignancy. Nephrotoxicity is a known side effect of several treatments, including cisplatin, carboplatin, ifosfamide, radiotherapy and nephrectomy, and can cause glomerular filtration rate (GFR) impairment, proteinuria, tubulopathy, and hypertension. Evidence about the long-term effects of these treatments on renal function remains inconclusive. It is important to know the risk of, and risk factors for, early and late adverse renal effects, so that ultimately treatment and screening protocols can be adjusted. This review is an update of a previously published Cochrane Review.

OBJECTIVES

To evaluate existing evidence on the effects of potentially nephrotoxic treatment modalities on the prevalence of renal dysfunction in survivors treated for childhood cancer with a median or mean survival of at least one year after cessation of treatment, where possible in comparison with the general population or CCS treated without potentially nephrotoxic treatment. In addition, to evaluate evidence on associated risk factors, such as follow-up duration, age at time of diagnosis and treatment combinations, as well as the effect of doses.

SEARCH METHODS

On 31 March 2017 we searched the following electronic databases: CENTRAL, MEDLINE and Embase. In addition, we screened reference lists of relevant studies and we searched the congress proceedings of the International Society of Pediatric Oncology (SIOP) and The American Society of Pediatric Hematology/Oncology (ASPHO) from 2010 to 2016/2017.

SELECTION CRITERIA

Except for case reports, case series and studies including fewer than 20 participants, we included studies with all study designs that reported on renal function (one year or longer after cessation of treatment), in CCS treated before the age of 21 years with cisplatin, carboplatin, ifosfamide, radiation involving the kidney region, a nephrectomy, or a combination of two or more of these treatments. When not all treatment modalities were described or the study group of interest was unclear, a study was not eligible for the evaluation of prevalence. We still included it for the assessment of risk factors if it had performed a multivariable analysis.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, 'Risk of bias' assessment and data extraction using standardised data collection forms. We performed analyses according to the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

Apart from the remaining 37 studies included from the original review, the search resulted in the inclusion of 24 new studies. In total, we included 61 studies; 46 for prevalence, six for both prevalence and risk factors, and nine not meeting the inclusion criteria, but assessing risk factors. The 52 studies evaluating the prevalence of renal dysfunction included 13,327 participants of interest, of whom at least 4499 underwent renal function testing. The prevalence of adverse renal effects ranged from 0% to 84%. This variation may be due to diversity of included malignancies, received treatments, reported outcome measures, follow-up duration and the methodological quality of available evidence.Seven out of 52 studies, including 244 participants, reported the prevalence of chronic kidney disease, which ranged from 2.4% to 32%.Of these 52 studies, 36 studied a decreased (estimated) GFR, including at least 432 CCS, and found it was present in 0% to 73.7% of participants. One eligible study reported an increased risk of glomerular dysfunction after concomitant treatment with aminoglycosides and vancomycin in CCS receiving total body irradiation (TBI). Four non-eligible studies assessing a total cohort of CCS, found nephrectomy and (high-dose (HD)) ifosfamide as risk factors for decreased GFR. The majority also reported cisplatin as a risk factor. In addition, two non-eligible studies showed an association of a longer follow-up period with glomerular dysfunction.Twenty-two out of 52 studies, including 851 participants, studied proteinuria, which was present in 3.5% to 84% of participants. Risk factors, analysed by three non-eligible studies, included HD cisplatin, (HD) ifosfamide, TBI, and a combination of nephrectomy and abdominal radiotherapy. However, studies were contradictory and incomparable.Eleven out of 52 studies assessed hypophosphataemia or tubular phosphate reabsorption (TPR), or both. Prevalence ranged between 0% and 36.8% for hypophosphataemia in 287 participants, and from 0% to 62.5% for impaired TPR in 246 participants. One non-eligible study investigated risk factors for hypophosphataemia, but could not find any association.Four out of 52 studies, including 128 CCS, assessed the prevalence of hypomagnesaemia, which ranged between 13.2% and 28.6%. Both non-eligible studies investigating risk factors identified cisplatin as a risk factor. Carboplatin, nephrectomy and follow-up time were other reported risk factors.The prevalence of hypertension ranged from 0% to 50% in 2464 participants (30/52 studies). Risk factors reported by one eligible study were older age at screening and abdominal radiotherapy. A non-eligible study also found long follow-up time as risk factor. Three non-eligible studies showed that a higher body mass index increased the risk of hypertension. Treatment-related risk factors were abdominal radiotherapy and TBI, but studies were inconsistent.Because of the profound heterogeneity of the studies, it was not possible to perform meta-analyses. Risk of bias was present in all studies.

AUTHORS' CONCLUSIONS

The prevalence of adverse renal effects after treatment with cisplatin, carboplatin, ifosfamide, radiation therapy involving the kidney region, nephrectomy, or any combination of these, ranged from 0% to 84% depending on the study population, received treatment combination, reported outcome measure, follow-up duration and methodological quality. With currently available evidence, it was not possible to draw solid conclusions regarding the prevalence of, and treatment-related risk factors for, specific adverse renal effects. Future studies should focus on adequate study designs and reporting, including large prospective cohort studies with adequate control groups when possible. In addition, these studies should deploy multivariable risk factor analyses to correct for possible confounding. Next to research concerning known nephrotoxic therapies, exploring nephrotoxicity after new therapeutic agents is advised for future studies. Until more evidence becomes available, CCS should preferably be enrolled into long-term follow-up programmes to monitor their renal function and blood pressure.

Histologic Abnormalities in Non-neoplastic Renal Parenchyma and the Risk of Chronic Kidney Disease Following Radical Nephrectomy

OBJECTIVE

To assess the association of histopathological parameters in non-neoplastic renal parenchyma with the development of new-onset chronic kidney disease (CKD) after radical nephrectomy.

PATIENTS AND METHODS

Data were extracted from 222 patients who underwent radical nephrectomy. The Modification of Diet in Renal Disease formula was used. The study end point was development of CKD, defined as an estimated glomerular filtration rate (eGFR) of less than 60 mL/min/1.73 m². A renal pathologist assessed three histologic features in the non-neoplastic parenchyma, namely global glomerulosclerosis (GS), arteriosclerosis (AS), and interstitial fibrosis (IF). For GS assessment, the percent of affected glomeruli was determined. AS was graded and divided into three groups, namely 1-0%-25%, 2-26%-50%, and 3-greater than 50%. IF was evaluated as absent or present.

RESULTS

After a mean follow-up of 49.06 months, the mean eGFR rate decrease was 26.5% after radical nephrectomy. Almost half of the patients (53.8%) developed CKD. For each 2.5% increase in GS, each point increase in Charlson comorbidity index (CCI), and each 10-year increase in patient's age, the eGFR decreased 28%, 33%, and 39%, respectively (P < .05). In a univariate analysis, age, CCI, GS, AS, IF, hypertension, and diabetes mellitus were associated with new-onset CKD after radical nephrectomy (P < .05). After multivariate logistic regression, CCI, GS, and baseline eGFR were associated with new-onset CKD after radical nephrectomy.

CONCLUSION

Histopathological evaluation of non-neoplastic renal parenchyma in patients who undergo radical nephrectomy can be used to predict the development of new-onset CKD.

Retrospective analysis of the predictive factors of renal function loss after uninephrectomy in patients with chronic kidney disease G3 to G5

Background

The rapid increase in glomerular filtration rate in a normal contralateral kidney after uninephrectomy is well known in living kidney donors but much less well described in chronic kidney disease (CKD). The purpose of this study is to determine the magnitude of this initial compensatory capacity in (CKD) groups 3 to 5 (G3 to G5) patients undergoing uninephrectomy and the clinical factors predicting it. This is a retrospective study of all cases (142) of uninephrectomy in patients with estimated glomerular filtration rate (eGFR; with MDRD equation) <60 ml/min/1.73 m², between 2003 and 2010, in two University of Montreal-affiliated teaching hospitals.

Methods

Baseline eGFR, patients’ comorbidities, and surgical characteristics and complications were noted. The change of eGFR after nephrectomy was evaluated; moreover, the expected post-op eGFR, i.e. without compensation by the contralateral kidney following surgery, was estimated in a sub-group of patients who had a preoperative renal scintigraphy and compared to the actual eGFR at hospital discharge.

Results

The mean change of eGFR from baseline to hospital discharge was −5 ± 12 ml/min/1.73 m² (−11 %; 95 % CI −16 to −6 %; P < 0.001). In univariate and multivariate analyses, baseline eGFR did not influence significantly these results. However, in the multivariate model, radical nephrectomy vs. partial nephrectomy and preoperative hypertension predicted a worse renal outcome. In the sub-group of patients with preoperative renal scintigraphy, the actual eGFR at hospital discharge was also higher than expected from the renal split function (13 ml/min/1.73 m²; 95 % CI 10 to 16; P < 0.001).

Conclusions

After uninephrectomy, the contralateral kidney in patients with CKD G3 to G5 still has a clinically significant initial compensatory capacity. The compensation is statistically smaller if the patient had hypertension or a radical uninephrectomy. This initial compensation is rapid and most probably haemodynamic (hyperfiltration). However, most of the included patients had a CKD G3, limiting the strength of the conclusion for the G4 toG5 patients; the length of observation covers the early postoperative period, i.e. less than 2 weeks, in more than half of the cohort.

A novel heart failure mice model of hypertensive heart disease by angiotensin II infusion, nephrectomy, and salt loading

Although the mouse heart failure (HF) model of hypertensive heart disease (HHD) is useful to investigate the pathophysiology and new therapeutic targets for HHD, the model using simple experimental procedures and stable phenotypes has not been established. This study aimed to develop a novel mouse HF model of HHD by combining salt loading and uninephrectomy with ANG II infusion. Eight-week-old C57BL/6 male mice were treated with ANG II infusion (AT), ANG II infusion and uninephrectomy (AN), ANG II infusion and salt loading (AS), or ANG II infusion, uninephrectomy, and salt loading (ANS). Systolic blood pressure was significantly elevated and left ventricular (LV) hypertrophy was found in AT, AN, AS, and ANS mice, and there were no significant differences in those parameters between the four groups. At 6 wk after the procedures, only ANS mice showed significant decreases in LV fractional shortening and increases in lung weight with a high incidence. This phenotype was reproducible, and there were few perioperative or early deaths in the experimental procedures. Severe LV fibrosis was found in ANS mice. Oxidative stress was enhanced and small GTPase Rac1 activity was upregulated in the hearts of ANS mice. After the addition of salt loading and uninephrectomy to the ANG II infusion mouse model, cardiac function was significantly impaired, and mice developed HF. This might be a novel and useful mouse HF model to study the transition from compensated LV hypertrophy to HF in HHD.