Kidney Outcomes and Hypertension in Survivors of Wilms Tumor: A Prospective Cohort Study

Circulating leptin is associated with adverse vascular changes in young adult survivors of childhood cancer

INTRODUCTION

Proteomics may help discover novel biomarkers and underlying mechanisms for cardiovascular disease. This could be useful for childhood cancer survivors as they show an increased risk of cardiovascular disease. The aim of this study was to investigate circulating cardiovascular proteins in young adult survivors of childhood cancer and their relationship to previously reported subclinical cardiovascular disease.

METHODS

Ninety-two cardiovascular proteins were measured in 57 childhood cancer survivors and in 52 controls. For proteins that were significantly different between childhood cancer survivors and controls, we performed correlations between protein levels and measures of peripheral arterial stiffness (carotid distensibility and stiffness index, and augmentation index) and endothelial dysfunction (reactive hyperemia index).

RESULTS

Leptin was significantly higher in childhood cancer survivors compared to controls (normalized protein expression units: childhood cancer survivors 6.4 (1.5) versus 5.1 (1.7), p < 0.0000001) after taking multiple tests into account. Kidney injury molecule-1, MER proto-oncogene tyrosine kinase, selectin P ligand, decorin, alpha-1-microglobulin/bikunin precursor protein, and pentraxin 3 showed a trend towards group differences (p < 0.05). Among childhood cancer survivors, leptin was associated with anthracycline treatment after adjustment for age, sex, and body mass index (p < 0.0001). Higher leptin correlated with lower carotid distensibility after adjustment for age, sex, body mass index, and treatments with radiotherapy and anthracyclines (p = 0.005).

CONCLUSION

This proteomics approach identified that leptin is higher in young asymptomatic adult survivors of childhood cancer than in healthy controls and is associated with adverse vascular changes. This could indicate a role for leptin in driving the cardiovascular disease burden in this population.

Hypertension in Wilms tumor

Wilms tumor (WT) represents over 90% of all pediatric kidney tumors. Children with WT often present acutely with hypertension which resolves in the short term after nephrectomy. However, WT survivors have increased long-term risk of hypertension, primarily due to decreased nephron mass after nephrectomy, with additional insults from possible exposure to abdominal radiation and nephrotoxic therapies. The diagnosis of hypertension may be improved by ambulatory blood pressure monitoring (ABPM), as several recent single-center studies have shown a substantial proportion of WT survivors with masked hypertension. Current gaps in knowledge include determining which WT patients may benefit from routine screening with ABPM, correlation of casual and ABPM parameters with cardiac abnormalities, and longitudinal assessment of cardiovascular and kidney parameters in relation to appropriate treatment of hypertension. This review aims to summarize the most recent literature on hypertension presentation and management at the time of WT diagnosis as well as the long-term hypertension risk and impact on kidney and cardiovascular outcomes in WT survivors.

Efficacy and late kidney effects of nephron-sparing surgery in the management of unilateral Wilms tumor: a systematic review and meta-analysis

To evaluate the efficiency and long-term renal function of nephron sparing surgery (NSS) in unilateral WT patients compared with radical nephrectomy (RN). The review was performed following Cochrane Handbook guidelines and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We searched five databases (Pubmed, Embase, Scopus, Web of Science and Cochrane) for studies reporting the efficiency and late renal function of NSS and/or RN on February 10, 2023. Comparative studies were evaluated by Risk of Bias in Non-randomized Studies of Interventions (ROBINS-I) and RoB 2.0. Assessed outcomes included survival rate, relapse rate, eGFR, renal dysfunction and hypertension. 26 studies involving 10322 unilateral WT cases underwent RN and 657 unilateral WT cases underwent NSS were enrolled. Overall effect estimates demonstrated that NSS significantly increased eGFR at follow-up (SMD, 0.38; 95% CI 0.05-0.72; p = 0.025) compared to that at diagnosis, and RN did not significantly decrease eGFR at follow-up (SMD, - 0.33; 95% CI - 0.77-0.11; p = 0.142) compared to that at diagnosis. Moreover, no significant difference was found in outcomes of survivability (OR, 1.38; 95% CI 0.82-2.32; p = 0.226), recurrence (OR, 0.62; 95% CI 0.34-1.12; p = 0.114), eGFR at follow-up (SMD, 0.16; 95% CI - 0.36-0.69; p = 0.538), renal dysfunction (OR, 0.36; 95% CI 0.07-1.73; p = 0.200) and hypertension (OR, 0.17; 95% CI 0.03-1.10; p = 0.063). Current evidence suggests that NSS is safe and effective for unilateral WT patients, because it causes better renal function and similar oncological outcomes compared with RN. Future efforts to conduct more high-quality studies and explore sources of heterogeneity is recommended.

Masked Hypertension in Healthy Children and Adolescents: Who Should Be Screened?

PURPOSE OF REVIEW

The goal is to review masked hypertension (MH) as a relatively new phenomenon when patients have normal office BP but elevated out-of-office BP. Firstly, it was described in children in 2004. It has received increased attention in the past decade.

RECENT FINDINGS

The prevalence of MH in different pediatric populations differs widely between 0 and 60% based on the population studied, definition of MH, or method of out-of-office BP measurement. The highest prevalence of MH has been demonstrated in children with chronic kidney disease (CKD), obesity, diabetes, and after heart transplantation. In healthy children but with risk factors for hypertension such as prematurity, overweight/obesity, diabetes, chronic kidney disease, or positive family history of hypertension, the prevalence of MH is 9%. In healthy children without risk factors for hypertension, the prevalence of MH is very low ranging 0-3%. In healthy children, only patients with the following clinical conditions should be screened for MH: high-normal/elevated office BP, positive family history of hypertension, and those referred for suspected hypertension who have normal office BP in the secondary/tertiary center.

Long-Term Kidney and Cardiovascular Complications in Pediatric Cancer Survivors

OBJECTIVE

The objective of this study was to describe the burden of adverse kidney and hypertension outcomes in patients evaluated by pediatric nephrology in a multidisciplinary survivorship clinic.

STUDY DESIGN

Retrospective chart review of all patients followed up by nephrology in our multidisciplinary survivorship clinic from August 2013 to June 2021. Data included clinic blood pressure, longitudinal ambulatory blood pressure monitoring (ABPM), echocardiography, serum creatinine, and first-morning urine protein/creatinine ratios. For patients with multiple ABPMs, results of initial and most recent ABPMs were compared.

RESULTS

Of 422 patients followed in the multidisciplinary cancer survivorship clinic, 130 were seen by nephrology. The median time after therapy completion to first nephrology visit was 8 years. The most common diagnoses were leukemia/myelodysplastic syndrome (27%), neuroblastoma (24%), and Wilms tumor (15%). At the last follow-up, 68% had impaired kidney function, 38% had a clinical diagnosis of hypertension, and 12% had proteinuria. There were 91 ABPMs performed in 55 (42%) patients. Patients with multiple ABPMs (n = 21) had statistically significant reductions in overall median blood pressure loads: systolic initial load 37% vs most recent 10% (P = .005) and diastolic load 36% vs 14% (P = .017). Patients with impaired kidney function were more likely to have received ifosfamide. Patients with hypertension were more likely to have received total body irradiation or allogeneic stem cell transplant.

CONCLUSIONS

History of leukemia/myelodysplastic syndrome, neuroblastoma, and Wilms tumor was frequent among survivors seen by nephrology. There was significant improvement in cardiovascular measures with increased recognition of hypertension and subsequent treatment.

Meta-Analysis on Long-Term Outcomes of Pediatric Renal Cancer Survivors Following COG and SIOP Protocols

BACKGROUND

 Pediatric renal cancer survivors have higher rate of chronic renal disease and hypertension. These patients have similar survival rates when treated according to either Children's Oncology Group (COG) or International Society of Pediatric Oncology (SIOP) protocols. We aimed to compare the late outcome of these two approaches.

METHODS

 We performed a meta-analysis of all studies from 2000 to 2021; database search using keywords: long-term outcomes OR late effects, nephrectomy, pediatric renal cancer. For each protocol, data were collected, and the "pooled" outcomes were compared. Continuous and dichotomous variables were obtained with a 95% odds ratio.

RESULTS

 Sixteen studies with a total of 715 pediatric renal cancer survivors were analyzed. The mean follow-up time was 17.4 (standard deviation 5.6) years. Reduced renal function and hypertension were the most encountered long-term complications. The mean estimated glomerular filtration rate was similar in both protocols (101.62 vs. 101.70 mL/min/1.73 m²), while the prevalence of hypertension was 23% in COG and 10% in SIOP. The prevalence of secondary malignancy was 1.1% in COG and 6.7% in SIOP (1.1% vs. 6.7%, p ≤ 0.001). Chronic kidney disease was similar in both groups.

CONCLUSION

 A high prevalence of hypertension was observed among pediatric renal cancer survivors, as well as an increased risk of a secondary tumor. These results emphasize the importance of long-term follow-up into adulthood, to promptly diagnose any long-term side effects of the treatment. Thanks to the increased overall survival, future protocols will pay attention to the reduction of long-term sequelae.

Increased risk for kidney sequelae surrogates in survivors of Wilms tumor

BACKGROUND

There is evidence of increased risk of hypertension, albuminuria, and development of chronic kidney disease (CKD) in long-term follow-up of survivors of Wilms tumor (WT). However, most studies were conducted in heterogeneous groups, including patients with solitary kidney. In addition, little is known about tubular dysfunction. This study aimed to investigate kidney sequelae, including CKD development, hypertension, and glomerular and tubular damage in WT survivors.

METHODS

This cross-sectional, single-center study included 61 patients treated for WT. Surrogates for kidney sequelae were defined as presence of at least one of the following: decrease in GFR for CKD, hypertension detected by ambulatory blood pressure monitoring, albuminuria (albumin-to-creatinine ratio [ACR] > 30 mg/g), or increase in at least one tubular biomarker (beta-2-microglobulin, neutrophil gelatinase-associated lipocalin, kidney injury marker-1, and liver fatty acid-binding protein) in 24-h urine.

RESULTS

Median age of patients was 11.7 years, with median follow-up of 8.8 years. Thirty-eight patients (62%) had at least one surrogate for kidney sequelae. Twenty-four patients (39%) had CKD, 14 patients (23%) had albuminuria, 12 patients (21%) had hypertension, and 11 patients (18%) had tubular damage. Urine ACR was significantly higher in patients with advanced tumor stage and patients with nephrotoxic therapy than their counterparts (p < 0.05), but neither eGFR nor tubular biomarkers showed any association with tumor- or treatment-related factors.

CONCLUSIONS

A considerable number of patients with WT have kidney sequelae, especially early-stage CKD with a high prevalence. Albuminuria emerges as a marker associated with tumor stages and nephrotoxic treatment. A higher resolution version of the Graphical abstract is available as Supplementary information.

Hypertension in long-term childhood cancer survivors after treatment with potentially nephrotoxic therapy; DCCSS-LATER 2: Renal study

PURPOSE

To evaluate the prevalence of and risk factors for hypertension in childhood cancer survivors (CCSs) who were treated with potentially nephrotoxic therapies.

METHODS

In the Dutch Childhood Cancer Survivor Study LATER cohort part 2 renal study, 1024 CCS ≥5 years after diagnosis, aged ≥18 years at study participation, treated between 1963 and 2001 with nephrectomy, abdominal radiotherapy, total body irradiation (TBI), cisplatin, carboplatin, ifosfamide, high-dose cyclophosphamide (≥1 g/m² per single dose or ≥10 g/m² total) or haematopoietic stem cell transplantation participated and 500 controls from Lifelines. Hypertension was defined as blood pressure (BP) (mmHg) systolic ≥140 and/or diastolic ≥90 or receiving medication for diagnosed hypertension. At the study visit, the CKD-EPI 2012 equation including creatinine and cystatin C was used to estimate the glomerular filtration rate (GFR). Multivariable regression analyses were used. For ambulatory BP monitoring (ABPM), hypertension was defined as BP daytime: systolic ≥135 and/or diastolic ≥85, night time: systolic ≥120 and/or diastolic ≥70, 24-h: systolic ≥130 and/or diastolic ≥80. Outcomes were masked hypertension (MH), white coat hypertension and abnormal nocturnal dipping (aND).

RESULTS

Median age at cancer diagnosis was 4.7 years (interquartile range, IQR 2.4-9.2), at study 32.5 years (IQR 27.7-38.0) and follow-up 25.5 years (IQR 21.4-30.3). The prevalence of hypertension was comparable in CCS (16.3%) and controls (18.2%). In 12% of CCS and 17.8% of controls, hypertension was undiagnosed. A decreased GFR (<60 ml/min/1.73 m²) was associated with hypertension in CCS (OR 3.4, 95% CI 1.4-8.5). Risk factors were abdominal radiotherapy ≥20 Gy and TBI. The ABPM-pilot study (n = 77) showed 7.8% MH, 2.6% white coat hypertension and 20.8% aND.

CONCLUSION

The prevalence of hypertension was comparable among CCS who were treated with potentially nephrotoxic therapies compared to controls, some of which were undiagnosed. Risk factors were abdominal radiotherapy ≥20 Gy and TBI. Hypertension and decreased GFR were associated with CCS. ABPM identified MH and a ND.

Wilms tumour

Wilms tumour (WT) is a childhood embryonal tumour that is paradigmatic of the intersection between disrupted organogenesis and tumorigenesis. Many WT genes play a critical (non-redundant) role in early nephrogenesis. Improving patient outcomes requires advances in understanding and targeting of the multiple genes and cellular control pathways now identified as active in WT development. Decades of clinical and basic research have helped to gradually optimize clinical care. Curative therapy is achievable in 90% of affected children, even those with disseminated disease, yet survival disparities within and between countries exist and deserve commitment to change. Updated epidemiological studies have also provided novel insights into global incidence variations. Introduction of biology-driven approaches to risk stratification and new drug development has been slower in WT than in other childhood tumours. Current prognostic classification for children with WT is grounded in clinical and pathological findings and in dedicated protocols on molecular alterations. Treatment includes conventional cytotoxic chemotherapy and surgery, and radiation therapy in some cases. Advanced imaging to capture tumour composition, optimizing irradiation techniques to reduce target volumes, and evaluation of newer surgical procedures are key areas for future research.

Late Kidney Effects of Childhood Cancer and Cancer Therapies

Childhood cancer therapy carries a high risk of treatment-related toxicities and complications that can impact kidney function. Although many of these adverse effects in the acute setting are well described, less is known about the latent effects of childhood cancer treatments on long-term kidney health. With decades of advancements in treatment protocols for many pediatric malignancies, more children than ever before are surviving into adulthood after being cured of their disease and with lower long-term morbidity. Although there is decreased prevalence of many chronic health conditions in cancer survivors, including gastrointestinal, endocrine, and musculoskeletal disorders, the long-term risk of kidney dysfunction has increased. In this review, we summarize the epidemiology of kidney disease in survivors of childhood cancer and describe the treatment-related risk factors associated with long-term impairment of kidney health. We organize this review by specific kidney disease-related outcomes of interest (chronic electrolyte abnormalities, CKD, proteinuria, and hypertension) to highlight what specific aspects of cancer treatment have been associated with these outcomes. Finally, we conclude by comparing different clinical practice guidelines that exist for long-term kidney function monitoring and include recommendations for when a childhood cancer survivor would benefit from long-term nephrology care.