Wilms tumor characteristics, surgical management, outcomes, and chronic kidney disease in children with WAGR syndrome: A report from the International WAGR Syndrome Association survey.

INTRODUCTION: Children with WAGR (Wilms tumor, aniridia, genitourinary anomalies, and range of development delays) syndrome are predisposed to Wilms tumor (WT) and intrinsic kidney disease. Using the comprehensive International WAGR Syndrome Association (IWSA) survey of children with WAGR syndrome, we analyzed tumor characteristics, treatment and congenital risk factors, and kidney function in children with WAGR and WT. METHODS: Descriptive statistics were utilized including demographics, treatment strategies, and patient outcomes. Comparisons were made between patients with WAGR and WT to those with WAGR alone. A multivariable logistic regression was completed for risk of developing WT and to identify predictors of chronic kidney disease (CKD). RESULTS: Sixty-four of 145 children with WAGR developed WT (44.1%). Three relapsed and one died. CKD developed in five children with WAGR without WT (5/81, 6.2%), and in 34 with WAGR and WT (34/64, 28.3%). Children with WAGR and WT were younger (p = .017), and had a greater association with CKD than WAGR children without WT (p < .0001). Two children with WT required hemodialysis, and one underwent kidney transplantation. By univariate analysis, CKD at any stage was associated with complete nephrectomy for the WT surgery (p < .0001), chemotherapy duration greater than 12 months, and three-drug therapy. Upon multivariate analysis, prior nephrectomy was the only significant variable (p = .0002). CONCLUSIONS: Epidemiological analysis of children with WAGR demonstrated favorable oncologic outcomes, but high rate of early CKD in those who developed WT. Further study of the use of nephron-sparing surgery in children with WAGR and strategies to delay or treat early CKD are needed.

Complex Chromosomal Rearrangement Involving Chromosomes 10 and 11, Accompanied by Two Adjacent 11p14.1p13 and 11p13p12 Deletions, Identified in a Patient with WAGR Syndrome.

Three years ago, our patient, at that time a 16-month-old boy, was discovered to have bilateral kidney lesions with a giant tumor in the right kidney. Chemotherapy and bilateral nephron-sparing surgery (NSS) for Wilms tumor with nephroblastomatosis was carried out. The patient also had eye affection, including glaucoma, eye enlargement, megalocornea, severe corneal swelling and opacity, complete aniridia, and nystagmus. The diagnosis of WAGR syndrome was suspected. De novo complex chromosomal rearrangement with balanced translocation t(10,11)(p15;p13) and a pericentric inversion inv(11)(p13q12), accompanied by two adjacent 11p14.1p13 and 11p13p12 deletions, were identified. Deletions are raised through the complex molecular mechanism of two subsequent rearrangements affecting chromosomes 11 and 10. WAGR syndrome diagnosis was clinically and molecularly confirmed, highlighting the necessity of comprehensive genetic testing in patients with congenital aniridia and/or WAGR syndrome.

Clinical characteristics and outcomes of children with WAGR syndrome and Wilms tumor and/or nephroblastomatosis: The 30-year SIOP-RTSG experience.

BACKGROUND: WAGR syndrome (Wilms tumor, aniridia, genitourinary anomalies, and range of developmental delays) is a rare contiguous gene deletion syndrome with a 45% to 60% risk of developing Wilms tumor (WT). Currently, surveillance and treatment recommendations are based on limited evidence. METHODS: Clinical characteristics, treatments, and outcomes were analyzed for patients with WAGR and WT/nephroblastomatosis who were identified through International Society of Pediatric Oncology Renal Tumor Study Group (SIOP-RTSG) registries and the SIOP-RTSG network (1989-2019). Events were defined as relapse, metachronous tumors, or death. RESULTS: Forty-three patients were identified. The median age at WT/nephroblastomatosis diagnosis was 22 months (range, 6-44 months). The overall stage was available for 40 patients, including 15 (37.5%) with bilateral disease and none with metastatic disease. Histology was available for 42 patients; 6 nephroblastomatosis without further WT and 36 WT, including 19 stromal WT (52.8%), 12 mixed WT (33.3%), 1 regressive WT (2.8%) and 2 other/indeterminable WT (5.6%). Blastemal type WT occurred in 2 patients (5.6%) after prolonged treatment for nephroblastomatosis; anaplasia was not reported. Nephrogenic rests were present in 78.9%. Among patients with WT, the 5-year event-free survival rate was 84.3% (95% confidence interval, 72.4%-98.1%), and the overall survival rate was 91.2% (95% confidence interval, 82.1%-100%). Events (n = 6) did not include relapse, but contralateral tumor development (n = 3) occurred up to 7 years after the initial diagnosis, and 3 deaths were related to hepatotoxicity (n = 2) and obstructive ileus (n = 1). CONCLUSIONS: Patients with WAGR have a high rate of bilateral disease and no metastatic or anaplastic tumors. Although they can be treated according to existing WT protocols, intensive monitoring of toxicity and surveillance of the remaining kidney(s) are advised. LAY SUMMARY: WAGR syndrome (Wilms tumor, aniridia, genitourinary anomalies, and range of developmental delays) is a rare genetic condition with an increased risk of developing Wilms tumor. In this study, 43 patients with WAGR and Wilms tumor (or Wilms tumor precursor lesions/nephroblastomatosis) were identified through the international registry of the International Society of Pediatric Oncology Renal Tumor Study Group (SIOP-RTSG) and the SIOP-RTSG network. In many patients (37.5%), both kidneys were affected. Disease spread to other organs (metastases) did not occur. Overall, this study demonstrates that patients with WAGR syndrome and Wilms tumor can be treated according to existing protocols. However, intensive monitoring of treatment complications and surveillance of the remaining kidney(s) are advised.

Results of Treatment for Patients With Multicentric or Bilaterally Predisposed Unilateral Wilms Tumor (AREN0534): A report from the Children's Oncology Group.

BACKGROUND: A primary objective of Children's Oncology Group study AREN0534 (Treatment for Patients With Multicentric or Bilaterally Predisposed, Unilateral Wilms Tumor) was to facilitate partial nephrectomy in 25% of children with bilaterally predisposed unilateral tumors (Wilms tumor/aniridia/genitourinary anomalies/range of developmental delays [WAGR] syndrome; and multifocal and overgrowth syndromes). The purpose of this prospective study was to achieve excellent event-free survival (EFS) and overall survival (OS) while preserving renal tissue through preoperative chemotherapy, completing definitive surgery by 12 weeks from diagnosis, and modifying postoperative chemotherapy based on histologic response. METHODS: The treating institution identified whether a predisposition syndrome existed. Patients underwent a central review of imaging studies through the biology and classification study AREN03B2 and then were eligible to enroll on AREN0534. Patients were treated with induction chemotherapy determined by localized or metastatic disease on imaging (and histology if a biopsy had been undertaken). Surgery was based on radiographic response at 6 or 12 weeks. Further chemotherapy was determined by histology. Patients who had stage III or IV disease with favorable histology received radiotherapy as well as those who had stage I through IV anaplasia. RESULTS: In total, 34 patients were evaluable, including 13 males and 21 females with a mean age at diagnosis of 2.79 years (range, 0.49-8.78 years). The median follow-up was 4.49 years (range, 1.67-8.01 years). The underlying diagnosis included Beckwith-Wiedemann syndrome in 9 patients, hemihypertrophy in 9 patients, multicentric tumors in 10 patients, WAGR syndrome in 2 patients, a solitary kidney in 2 patients, Denys-Drash syndrome in 1 patient, and Simpson-Golabi-Behmel syndrome in 1 patient. The 4-year EFS and OS rates were 94% (95% CI, 85.2%-100%) and 100%, respectively. Two patients relapsed (1 tumor bed, 1 abdomen), and none had disease progression during induction. According to Response Evaluation Criteria in Solid Tumor 1.1 criteria, radiographic responses included a complete response in 2 patients, a partial response in 21 patients, stable disease in 11 patients, and progressive disease in 0 patients. Posttherapy histologic classification was low-risk in 13 patients (including the 2 complete responders), intermediate-risk in 15 patients, and high-risk in 6 patients (1 focal anaplasia and 5 blastemal subtype). Prenephrectomy chemotherapy facilitated renal preservation in 22 of 34 patients (65%). CONCLUSIONS: A standardized approach of preoperative chemotherapy, surgical resection within 12 weeks, and histology-based postoperative chemotherapy results in excellent EFS, OS, and preservation of renal parenchyma.

Molecular analysis of patients with aniridia in Russian Federation broadens the spectrum of PAX6 mutations.

Congenital aniridia is a severe autosomal dominant congenital panocular disorder, mainly associated with pathogenic variants in the PAX6 gene. The objective of the study was to investigate the mutational and clinical spectra of congenital aniridia in a cohort of 117 patients from Russia. Each patient underwent detailed ophthalmological examination. From 91 unrelated families, 110 patients were diagnosed with congenital aniridia and 7 with WAGR syndrome (Wilms tumor, Aniridia, Genitourinary anomalies, and mental Retardation syndrome). The clinical presentation in aniridia patients varied from the complete bilateral absence of the iris (75.5%) to partial aniridia or iris hypoplasia (24.5%). Additional ocular abnormalities were consistent with previous reports. In our cohort, we saw a previously not described high percentage of patients (45%) who showed non-ocular phenotypes. Prevalence of deletions coherent with WAGR syndrome appeared to be 19.4% out of sporadic patients. Among the other aniridia cases, PAX6 deletions were identified in 18 probands, and small intragenic changes were detected in 58 probands with 27 of these mutations being novel and 21 previously reported. In 3 families mosaic mutation was transmitted from a subtly affected parent. Therefore, PAX6 mutations explained 96.7% of aniridia phenotypes in this study with only 3 of 91 probands lacking pathogenic variants in the gene.

Renal involvement in tuberous sclerosis complex with emphasis on cystic lesions.

INTRODUCTION: Tuberous sclerosis complex (TSC) involves frequently the kidneys. Lesions encompass mainly angiomyolipoma and cysts. The disease can be associated with autosomal dominant polycystic kidney disease leading to the contiguous gene syndrome (CGS) The objectives of the present study were to review the US appearances of the renal involvement in children affected by classical TSC or by the CGS and to verify whether it is possible to differentiate between both entities. The evolution of the lesions through time was also studied. MATERIALS AND METHODS: 55 cases of patients <16 years with STB were reviewed by two pediatric radiologists. Clinical data reviewed included age at diagnosis, genetic assessment and complications; US data reviewed included renal size, type of lesions (angiomyolipoma-AML, or cysts), number and location as well as their evolution with time. Complications were also analyzed. RESULTS: 30 patients (56 %) had at least one kidney lesion (27 classical TSC and 3 CGS). On the basis of the US findings, these patients were separated into four groups. Group 1 (9 patients) displayed microscopic (diffuse) AML; group 2 (3 patients) displayed macroscopic AML; group 3 (9 patients) displayed only renal cysts and group 4 (9 patients) displayed the association of AML and cysts. Increased renal size, the large number and size of cystic lesions were suggestive of the CGS. The isolated AML were suggestive of classical STB. The average growth of angiomyolipoma was low before age of 12 and exceeded 4 mm/year thereafter. CONCLUSION: In children with TSC, renal involvement is common. Some US criteria can help to suggest the diagnosis of CGS. The growth of angiomyolipoma is slow before 12 years and accelerates thereafter. Complications are rare.

Facial dysostoses: Etiology, pathogenesis and management.

Approximately 1% of all live births exhibit a minor or major congenital anomaly. Of these approximately one-third display craniofacial abnormalities which are a significant cause of infant mortality and dramatically affect national health care budgets. To date, more than 700 distinct craniofacial syndromes have been described and in this review, we discuss the etiology, pathogenesis and management of facial dysostoses with a particular emphasis on Treacher Collins, Nager and Miller syndromes. As we continue to develop and improve medical and surgical care for the management of individual conditions, it is essential at the same time to better characterize their etiology and pathogenesis. Here we describe recent advances in our understanding of the development of facial dysostosis with a view towards early in utero identification and intervention which could minimize the manifestation of anomalies prior to birth. The ultimate management for any craniofacial anomaly however, would be prevention and we discuss this possibility in relation to facial dysostosis.

An uncommon presentation of WAGR syndrome with persistent fetal vasculature.

Aniridia is an autosomal dominant congenital malformation associated with mutations in the PAX6 gene. It can be associated with deletion in the contiguous WT1 gene, leading to WAGR syndrome, characterized by Wilm tumor, aniridia, genitourinary anomalies, and mental retardation. Persistent fetal vasculature is a developmental malformation caused by incomplete regression of hyaloid vasculature. Most cases of persistent fetal vasculature occur sporadically; however, some inherited forms are described. We report a case of genetically confirmed WAGR associated with congenital cataract and persistent fetal vasculature.

Unusual Presentation in WAGR Syndrome: Expanding the Phenotypic and Genotypic Spectrum of the Diseases.

The deletion of chromosome 11p13 involving the WT1 and PAX6 genes has been shown to cause WAGR syndrome (OMIM #194072), a rare genetic disorder that features Wilms' tumor, aniridia, genitourinary anomalies, as well as mental retardation. In this study, we expand the genotypic and phenotypic spectrum of WAGR syndrome by reporting on six patients from six unrelated families with different de novo deletions located on chromosome 11p13. Very rare phenotypes of lens automated absorption and lens thinning were detected in four of the six patients. We assessed the involvement of the ARL14EP gene in patients with and without severe lens abnormalities and found that its deletion may worsen the lens abnormalities in these patients.

Preferentially Paternal Origin of De Novo 11p13 Chromosome Deletions Revealed in Patients with Congenital Aniridia and WAGR Syndrome.

The frequency of pathogenic large chromosome rearrangements detected in patients with different Mendelian diseases is truly diverse and can be remarkably high. Chromosome breaks could arise through different known mechanisms. Congenital PAX6-associated aniridia is a hereditary eye disorder caused by mutations or chromosome rearrangements involving the PAX6 gene. In our recent study, we identified 11p13 chromosome deletions in 30 out of 91 probands with congenital aniridia or WAGR syndrome (characterized by Wilms' tumor, Aniridia, and Genitourinary abnormalities as well as mental Retardation). The loss of heterozygosity analysis (LOH) was performed in 10 families with de novo chromosome deletion in proband. In 7 out of 8 informative families, the analysis revealed that deletions occurred at the paternal allele. If paternal origin is not random, chromosome breaks could arise either (i) during spermiogenesis, which is possible due to specific male chromatin epigenetic program and its vulnerability to the breakage-causing factors, or (ii) in early zygotes at a time when chromosomes transmitted from different parents still carry epigenetic marks of the origin, which is also possible due to diverse and asymmetric epigenetic reprogramming occurring in male and female pronuclei. Some new data is needed to make a well-considered conclusion on the reasons for preferential paternal origin of 11p13 deletions.

Small glomeruli in WAGR (Wilms Tumor, Aniridia, Genitourinary Anomalies and Mental Retardation) syndrome.

BACKGROUND: Wilms tumor, aniridia, genitourinary anomalies, and mental retardation (WAGR) syndrome is a genetic disorder caused by a deletion of band 11p13, which results in the loss of 1 allele of the Wilms tumor suppressor gene (WT1). It is not classically associated with nephropathies, but increased rates of renal failure are reported. Denys-Drash syndrome (DDS), caused by mutations in the WT1 gene affecting the third or second zinc finger, is characterized by a triad of glomerulopathy progressing rapidly to end-stage renal disease, male hermaphroditism, and Wilms tumor. In patients with DDS, small glomeruli were observed. METHODS: We reviewed histological findings of nontumoral kidney samples of 7 patients with WAGR syndrome at the time of tumor surgery. RESULTS: Median glomerular diameter was 110 +/- 37 microm in patients with WAGR syndrome versus 125 +/- 18.5 microm in controls (P < 0.0001). CONCLUSION: The presence of small glomeruli in patients with WAGR syndrome, as in those with DDS, suggests a specific defect of WT1 function in development and a specific role of WT1 allele loss in the development of renal failure in these patients.

WAGR syndrome: is the 'R' always justified?

Although mild-to-moderate intellectual disability is usually considered part of WAGR syndrome (Wilms' tumour (WT), Aniridia, Genital abnormalities, and metal Retardation, due to 11p13 deletion) the neuropsychological profile of the syndrome is little reported in the literature. We report about a 12-year-old boy presenting with WAGR syndrome (WT, right complete aniridia, bilateral cryptorchidism, interstitial deletion involving band 11p13) but with no mental retardation. An in-depth clinical evaluation revealed no behavioural or social problems and the child's neuropsychological profile was found to be within the normal range for all abilities and functions investigated (with the exception of an impulsive cognitive style and some difficulties in academic skills). This case underlines the importance of in-depth neuropsychological evaluation that includes not only IQ measurement, but also examination of attention and academic skills, in order to establish the complete phenotypical profile of WAGR patients, rather than labelling them as learning disabled (i.e. mental retardation).

[Multicystic renal tumor in a patient with WAGR syndrome]. / Multizystischer Nierentumor bei einem Patienten mit WAGR-Syndrom.

The WAGR syndrome is a combination of Wilms' tumor, aniridia, genitourinary anomalies, and mental retardation. We report on a 2-year-old boy, who had a deletion of the aniridia gene PAX6 and the Wilms' tumor gene 1 (WT1 gene). At the age of 23 months, a 1.7 x 1.9 cm-sized intrarenal tumor was detected by ultrasound examination. According to the protocol of the SIOP study, a cycle of neoadjuvant chemotherapy was prescribed followed by a left-sided nephrectomy. However, postsurgical histomorphology failed to confirm the suspected diagnosis of Wilms' tumor and instead revealed dysgenetic cysts of the kidney. Based on the image morphology in connection with the deletion of the WT1 gene, the tentative diagnosis of a nephroblastoma had to be made. The study protocol of the SIOP does not permit another therapy algorithm.

Characteristics and outcomes of children with the Wilms tumor-Aniridia syndrome: a report from the National Wilms Tumor Study Group.

PURPOSE: Children with the rare Wilms tumor (WT)-aniridia (WAGR) syndrome have not had systematic evaluation of their clinical and pathologic features. We compared demographics, disease characteristics, and treatment outcomes in a large cohort of WT patients who did or did not have the WAGR syndrome. PATIENTS AND METHODS: Clinical and pathology records were reviewed for 8,533 patients enrolled between 1969 and 2002 by the National Wilms Tumor Study Group. RESULTS: Sixty-four patients (0.75%) had the WAGR syndrome. For WAGR and non-WAGR patients, respectively, the average birth weights (2.94 and 3.45 kg), median ages at diagnosis (22 and 39 months), and the percentages with bilateral disease (17% and 6%), metastatic disease (2% and 13%), favorable histology (FH) tumors (100% and 92%), and intralobar nephrogenic rests (ILNR; 77% and 22%) all differed. Survival estimates for WAGR and non-WAGR patients were 95% +/- 3% and 92% +/- 0.3% at 4 years but 48% +/- 17% and 86% +/- 1.0%, respectively, at 27 years from diagnosis. Five late deaths in WAGR patients were from end-stage renal disease (ESRD). CONCLUSION: The excess of bilateral disease, ILNR-associated FH tumors of mixed cell type, and early ages at diagnosis in WAGR patients all fit the known phenotypic spectrum of constitutional deletion of chromosome 11p13. Despite a favorable response of their WT to treatment, WAGR patients have a high risk of ESRD as they approach adulthood. The renal pathology associated with this apparent late manifestation of WT1 deletion, and the explanation for the abnormally low birth weights in patients with del 11p13, have yet to be determined.

Aniridia as part of a WAGR syndrome in a girl whose brother presented hypospadias.

Aniridia can arise as part of the WAGR syndrome (Wilms tumour. aniridia, genitourinary anomalies, and mental retardation), due to a deletion or chromosomal region 11p13. We report a girl with a complete WAGR syndrome, whose brother presented hypospadias. Cytogenetic, FISH and molecular studies showed a deletion in one chromosome 11 of the patient. No cytogenetic rearrangement or deletion affecting the genes included in this region (PAX6 and WT1) were observed in her brother and parents. This excludes a higher risk than that of the general population for developing Wilms tumour in the brother and supports that the presence of WAGR syndrome in the patient and hypospadias in her brother is a chance association. We conclude that the identification and definition of the deletions in the WAGR region, which include the WT1 locus are important in order to identify a high tumour risk in infant patients with aniridia including those without other WAGR anomalies.

Wilms' tumor and associated malformations; report of two cases with WAGR and Drash syndrome.

The combination of Wilms' tumor with aniridia, ambiguous genitalia/gonadoblastoma and mental retardation is defined as WAGR syndrome. The association with pseudohermaphroditism and nephropathy was also described as Drash syndrome. Here we report two cases with WAGR and Drash syndrome. The importance of early recognition and appropriate management of Wilms' tumor with those concurrent malformations is highlighted.

Obesity and WAGR syndrome.

We describe a 15-year-old boy with WAGR syndrome and obesity and suggest that obesity should be added to the WAGR spectrum. It is also suggested that a putative gene for obesity might be located within the 11p13 band.

The modifier effect of the BDNF gene in the phenotype of the WAGRO syndrome.

Individuals who are carriers of deletions of various sizes that cause haploinsufficiency in the contiguous WT1 and PAX6 genes, located on chromosome 11p13 approximately 4 Mb centromeric to the BDNF gene, are susceptible to Wilms tumor, aniridia, mental retardation, genitourinary anomalies and obesity (WAGRO syndrome). The molecular characterization of the wide deletion 11p15.1p12 arr (18676926-36576388) x1 dn in a child with 3 years and 4 months of age only affected by aniridia, predicts not only other serious associated diseases, but also allows us to hypothesize a specific phenotype of mental impairment, conduct alterations and childhood obesity, possibly added to the onset of metabolic alterations. The variable appearance and/or description of haploinsufficiency for obesity susceptibility in the WAGR syndrome mainly depends on the critical region located within 80 kb of exon 1 of BDNF. The relationship between genetic variation based on the genotype combinations of the 4 gene SNPs tagging the BDNF gene and the body mass index (BMI) was studied. The polymorphic variability was similarly distributed in 218 children suffering a severe and non-syndromic obesity from families at high risk for obesity, as compared with 198 controls. The corroborated role of the BDNF gene as highly susceptible to severe syndromic obesity has not already been evidenced in the molecular basis of overweight attributed to the common polygenic principles. Its potential role as risk modifier variant to provoke more severe phenotype has not yet been demonstrated. Some genetic variants of brain-derived neurotrophic factor (BDNF) have resulted in important disorders of energy balance, but it is essential to know exactly their deleterious human capacity because they play a fundamental role in the development and plasticity of the central nervous system in regulating food intake. The existence of polymorphic amino acid changes of unknown functional significance in patients carrying the haploinsufficiency of the BDNF gene could constitute an adequate model to study in depth their effects.