Late effects of Wilms' tumor treatment. / Efectos tardíos del tratamiento del tumor de Wilms.

INTRODUCTION: Wilms' tumor (WT) is the most frequent renal tumor in childhood. Therapeutic management progression has increased survival rates, and as a result, long-term adverse effects. MATERIALS AND METHODS: A descriptive retrospective study of a case series from 1977 to 2023 was carried out. The characteristics of the treatments received and the adverse effects listed on medical records were analyzed via phone surveys. RESULTS: 50 patients (25 boys-25 girls) with a mean age of 3.6 years (3 months-11 years) at diagnosis were included. Most of them (94%) were treated according to the protocol established by the European standards of pediatric oncology, which are characterized by the use of neoadjuvant chemotherapy. In one patient, the American treatment scheme was followed. The most common drugs used were vincristine and actinomycin D (78%). Only 12 patients (28%) received anthracyclines. Unilateral nephrectomy was the most frequent surgical technique (84%). Renal disorders were the most common (46%). However, the occurrence of second neoplasias (9%) and reproductive disorders (8% between boys and girls) had a greater impact on patients' quality of life. Multiple - cardiac (23%), endocrine (26%), and pulmonary (15%) - disorders associated with the treatments received were reported. CONCLUSIONS: WT treatment has an impact on health. Adequate and rigorous surgery, close follow-up, and limiting chemotherapy doses and radiation exposure can minimize long-term sequels.

INTRODUCCION: El tumor de Wilms (TW) es el tumor renal más frecuente en la infancia. La evolución del manejo terapéutico ha incrementado la tasa de supervivencia y como consecuencia, los efectos secundarios a largo plazo. MATERIAL Y METODOS: Realizamos un estudio retrospectivo descriptivo a partir de una serie de casos entre 1977 y 2023. Estudiamos las características de los tratamientos recibidos y los efectos secundarios que constan en su historia clínica y a través de cuestionarios telefónicos. RESULTADOS: Localizamos 50 pacientes (25 hombres-25 mujeres) con edad media al diagnóstico de 3,6 años (3 meses-11 años). La mayoría fueron tratados según protocolo vigente de las guías europeas de oncología pediátrica (94%) caracterizadas por el uso de quimioterapia neoadyuvante. En un paciente Se siguió el esquema americano de tratamiento. Los fármacos más utilizados fueron vincristina y actinomicina D (78%); solo 12 pacientes (28%) recibieron antraciclinas. La nefrectomía unilateral fue la técnica quirúrgica más empleada (84%). Las alteraciones renales fueron las más frecuentes (46%). Sin embargo, la aparición de segundas neoplasias (9%) y aquellas alteraciones relacionadas con la reproducción (8% entre hombres y mujeres) suponen un mayor impacto en la calidad de vida de los pacientes. Se describen múltiples alteraciones: cardíacas (23%), endocrinas (26%) o pulmonares (15%) relacionadas con los tratamientos recibidos. CONCLUSIONES: El tratamiento del TW afecta a la salud general. Una cirugía adecuada y rigurosa, limitar las dosis de quimioterapia, minimizar la exposición a la radiación y un seguimiento estrecho puede minimizar las secuelas a largo plazo.

Automation of Wilms' tumor segmentation by artificial intelligence.

BACKGROUND: 3D reconstruction of Wilms' tumor provides several advantages but are not systematically performed because manual segmentation is extremely time-consuming. The objective of our study was to develop an artificial intelligence tool to automate the segmentation of tumors and kidneys in children. METHODS: A manual segmentation was carried out by two experts on 14 CT scans. Then, the segmentation of Wilms' tumor and neoplastic kidney was automatically performed using the CNN U-Net and the same CNN U-Net trained according to the OV2ASSION method. The time saving for the expert was estimated depending on the number of sections automatically segmented. RESULTS: When segmentations were performed manually by two experts, the inter-individual variability resulted in a Dice index of 0.95 for tumor and 0.87 for kidney. Fully automatic segmentation with the CNN U-Net yielded a poor Dice index of 0.69 for Wilms' tumor and 0.27 for kidney. With the OV2ASSION method, the Dice index varied depending on the number of manually segmented sections. For the segmentation of the Wilms' tumor and neoplastic kidney, it varied respectively from 0.97 to 0.94 for a gap of 1 (2 out of 3 sections performed manually) to 0.94 and 0.86 for a gap of 10 (1 section out of 6 performed manually). CONCLUSION: Fully automated segmentation remains a challenge in the field of medical image processing. Although it is possible to use already developed neural networks, such as U-Net, we found that the results obtained were not satisfactory for segmentation of neoplastic kidneys or Wilms' tumors in children. We developed an innovative CNN U-Net training method that makes it possible to segment the kidney and its tumor with the same precision as an expert while reducing their intervention time by 80%.

Does bilateral Wilms' tumor involving the collecting system in children have a worse prognosis?

BACKGROUND: The literature on nephron-sparing surgery (NSS) in children with bilateral Wilms' tumors (BWT) involving the collection system is mostly comprised of case reports. The present study aimed to summarize the clinical characteristics, treatments, and prognosis of children with BWT involving the collecting system admitted to our pediatric surgery center compared with those whose tumors did not involve the collecting system. A secondary aim was to discuss how to preserve more kidney parenchyma and prevent long-term renal failure under the premise of preventing tumor recurrence. METHODS: Patients with BWT admitted to our pediatric surgery center between January 2008 and June 2022 were reviewed. All included patients were grouped according to the relationship between the tumor and collecting system according to the intraoperative findings. Group I included children with tumor infiltrating the collecting system, group II included children with tumor growing into the collecting system, and group III included children whose tumor did not involve the collecting system. The clinical features, treatments and prognosis of the patients were analyzed. RESULTS: Seventy patients were enrolled, including 20 patients with 25 sides of tumors infiltrating the collecting system in group I,10 patients with 13 sides of tumors growing into the collecting system in group II, and 40 patients in group III. There was no significant difference in patients age and gender between group I and group II. In total, 20 patients in group I and 9 patients in group II had partial response (PR) after neoadjuvant chemotherapy. In group I, 22 of 25 sides of tumors underwent NSS; in group II, 11 of 13 sides of tumors underwent NSS. During an average follow-up of 47 months, in group I, 6/20 patients relapsed and 2/20 patients died; in group II, 3/10 patients relapsed and 1/10 patient died. There was no significant difference in 4-year overall survival (OS) rate among groups I, II and III (86.36% vs. 85.71%vs. 91.40%, P = 0.902). CONCLUSIONS: To preserve renal parenchyma, NSS is feasible for children with BWT involving the collecting system. There was no significant difference in postoperative long-term OS between patients with BWT involving the collecting system and not involving the collecting system.

N6-methyladenosine modification of circMARK2 enhances cytoplasmic export and stabilizes LIN28B, contributing to the progression of Wilms tumor.

BACKGROUND: The potential involvement of circular RNAs (circRNAs) and N6-methyladenosine (m6A) modification in the progression of Wilms tumor (WT) has not been fully elucidated. This study investigates the regulatory mechanisms and clinical significance of m6A-modified circMARK2 and its role in WT progression. METHODS: We identified dysregulated circRNAs through deep sequencing and validated their expression by qRT-PCR in WT tissues. The biological functions of circMARK2 were assessed using clone formation, transwell migration, and orthotopic animal models. To dissect the underlying mechanisms, we employed RNA immunoprecipitation, RNA pull-down, dual-luciferase reporter assays, Western blotting, and immunofluorescence and immunohistochemical staining. RESULTS: CircMARK2, upregulated in WT tissues, was found to be m6A-modified and promoted cytoplasmic export. It facilitated WT progression by stabilizing LIN28B mRNA through the circMARK2/IGF2BP2 interaction. In vitro and in vivo studies demonstrated that circMARK2 enhances the malignant behavior of WT cells. Clinically, higher circMARK2 levels in tumor tissues of WT patients were linked to increased tumor aggressiveness and reduced survival rates. CONCLUSIONS: Our study provides the first comprehensive evidence that m6A-modified circMARK2 contributes to WT progression by enhancing LIN28B mRNA stability, promoting cellular aggressiveness. CircMARK2 emerges as a potential biomarker for prognosis and a promising target for therapeutic intervention in WT, underscoring the clinical relevance of m6A modification in pediatric renal cancer.

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.

Single-cell multiomics reveals ENL mutation perturbs kidney developmental trajectory by rewiring gene regulatory landscape.

How disruptions to normal cell differentiation link to tumorigenesis remains incompletely understood. Wilms tumor, an embryonal tumor associated with disrupted organogenesis, often harbors mutations in epigenetic regulators, but their role in kidney development remains unexplored. Here, we show at single-cell resolution that a Wilms tumor-associated mutation in the histone acetylation reader ENL disrupts kidney differentiation in mice by rewiring the gene regulatory landscape. Mutant ENL promotes nephron progenitor commitment while restricting their differentiation by dysregulating transcription factors such as Hox clusters. It also induces abnormal progenitors that lose kidney-associated chromatin identity. Furthermore, mutant ENL alters the transcriptome and chromatin accessibility of stromal progenitors, resulting in hyperactivation of Wnt signaling. The impacts of mutant ENL on both nephron and stroma lineages lead to profound kidney developmental defects and postnatal mortality in mice. Notably, a small molecule inhibiting mutant ENL's histone acetylation binding activity largely reverses these defects. This study provides insights into how mutations in epigenetic regulators disrupt kidney development and suggests a potential therapeutic approach.

Screening of potential hub genes involved in Kidney Wilms tumor via bioinformatics analysis and experimental validation.

BACKGROUND: Wilms tumor (WT) is the most common pediatric embryonal tumor. Improving patient outcomes requires advances in understanding and targeting the multiple genes and cellular control pathways, but its pathogenesis is currently not well-researched. We aimed to identify the potential molecular biological mechanism of WT and develop new prognostic markers and molecular targets by comparing gene expression profiles of Wilms tumors and fetal normal kidneys. METHODS: Differential gene expression analysis was performed on Wilms tumor transcriptomic data from the GEO and TARGET databases. For biological functional analysis, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were utilized. Out of 24 hub genes identified, nine were found to be prognostic-related through univariate Cox regression analysis. These nine genes underwent LASSO regression analysis to enhance the predictive capability of the model. The key hub genes were validated in the GSE73209 datasets, and cell function experiments were conducted to identify the genes' functions in WiT-49 cells. RESULTS: The enrichment analysis revealed that DEGs were significantly involved in the regulation of angiogenesis and regulation of cell differentiation. 24 DEGs were identified through PPI networks and the MCODE algorithm, and 9 of 24 genes were related to WT patients' prognosis. EMCN and CCNA1 were identified as key hub genes, and related to the progression of WT. Functionally, over-expression of EMCN and CCNA1 knockdown inhibited cell viability, proliferation, migration, and invasion of Wilms tumor cells. CONCLUSIONS: EMCN and CCNA1 were identified as key prognostic markers in Wilms tumor, suggesting their potential as therapeutic targets. Differential gene expression and enrichment analyses indicate significant roles in angiogenesis and cell differentiation.

LMO family gene polymorphisms and Wilms tumor susceptibility in Chinese children: a five-center case-control study.

BACKGROUND: Wilms tumor is the most prevalent embryonal kidney malignancy in children worldwide. Previous genome-wide association study (GWAS) identified that LIM domain only 1 (LMO1) gene polymorphisms affected the susceptibility to develop certain tumor types. Apart from LMO1, the LMO gene family members also include LMO2-4, each of which has oncogenic potential. METHODS: We conducted this five-center case‒control study to assess the correlations between single nucleotide polymorphisms in LMO family genes and Wilms tumor susceptibility. Odds ratios and 95% confidence intervals were calculated to evaluate the strength of the association. RESULTS: We found LMO1 rs2168101 G > T and rs11603024 C > T as well as LMO2 rs7933499 G > A were significantly associated with Wilms tumor risk. Stratified analysis demonstrated a protective role of rs2168101 GT/TT genotypes against Wilms tumor in the subgroups of age ≤ 18 months, males and clinical stages I/II compared to the rs2168101 GG genotype. Nevertheless, carriers with the rs11603024 TT genotype were more likely to have an increased risk of Wilms tumor than those with rs11603024 CC/CT genotypes in age > 18 months. And the rs11603024 was identified as a protective polymorphism for reducing the risk of Wilms tumor in the sex- and gender- subgroup. Likewise, carriers with the rs7933499 GA/AA genotypes were at significantly elevated risk of Wilms tumor in age ≤ 18 months and clinical stages I/II. CONCLUSION: Overall, our study identified the importance of LMO family gene polymorphisms on Wilms tumor susceptibility in Chinese children. Further investigations are needed to validate our conclusions.

Treatment abandonment in children with Wilms tumor at a national referral hospital in Uganda.

INTRODUCTION: The incidence of pediatric Wilms' tumor (WT) is high in Africa, though patients abandon treatment after initial diagnosis. We sought to identify factors associated with WT treatment abandonment in Uganda. METHODS: A cohort study of patients < 18 years with WT in a Ugandan national referral hospital examined clinical and treatment outcomes data, comparing children whose families adhered to and abandoned treatment. Abandonment was defined as the inability to complete neoadjuvant chemotherapy and surgery for patients with unilateral WT and definitive chemotherapy for patients with bilateral WT. Patient factors were assessed via bivariate logistic regression. RESULTS: 137 WT patients were included from 2012 to 2017. The mean age was 3.9 years, 71% (n = 98) were stage III or higher. After diagnosis, 86% (n = 118) started neoadjuvant chemotherapy, 59% (n = 82) completed neoadjuvant therapy, and 55% (n = 75) adhered to treatment through surgery. Treatment abandonment was associated with poor chemotherapy response (odds ratio [OR] 4.70, 95% confidence interval [CI] 1.30-17.0) and tumor size > 25 cm (OR 2.67, 95% CI 1.05-6.81). CONCLUSIONS: Children with WT in Uganda frequently abandon care during neoadjuvant therapy, particularly those with large tumors with poor response. Further investigation into the factors that influence treatment abandonment and a deeper understanding of tumor biology are needed to improve treatment adherence of children with WT in Uganda.

First incidence of extrarenal wilms tumor within the spinal canal in the adult population: a novel case report and literature review.

BACKGROUND: Wilms tumor (WT), also known as nephroblastoma, is rare in adults, accounting for merely 3% of all nephroblastomas or 0.2 cases per million individuals. Extrarenal Wilms tumor (ERWT) emerges outside the renal boundaries and comprises 0.5 to 1% of all WT cases, with even rarer incidences in adults. Oncogenic mutations associated with ectopic nephrogenic rests (NR) may contribute to ERWT development. Diagnosis involves surgical resection and pathology examination. Due to scarce cases, adults often rely on pediatric guidelines. We thoroughly searched PubMed, Scopus, and Web of Science databases to establish our case's uniqueness. To the best of our knowledge, this is the first documented incidence of extrarenal Wilms tumor within the spinal canal in the adult population. CASE PRESENTATION: A 22-year-old woman with a history of congenital lipo-myelomeningocele surgery as an infant presented with a 6-month history of back pain. This pain gradually resulted in limb weakness, paraparesis, and loss of bladder and bowel control. An MRI showed a 6 × 5 × 3 cm spinal canal mass at the L4-S1 level. Consequently, a laminectomy was performed at the L4-L5 level to remove the intramedullary tumor. Post-surgery histopathology and immunohistochemistry confirmed the tumor as ERWT with favorable histology without any teratomatous component. CONCLUSION: This report underscores the rarity of extrarenal Wilms tumor (ERWT) in adults, challenging conventional assumptions about its typical age of occurrence. It emphasizes the importance of clinical awareness regarding such uncommon cases. Moreover, the co-occurrence of spinal ERWTs and a history of spinal anomalies warrants further investigation.

[Identification of key genes in Wilms tumor based on high-throughput RNA sequencing and their impacts on prognosis and immune responses].

OBJECTIVE: To identify the key genes differentially expressed in Wilms tumor and analyze their potential impacts on prognosis and immune responses of the patients. METHODS: High-throughput RNA sequencing was used to identify the differentially expressed mRNAs in clinical samples of Wilms tumor and paired normal tissues, and their biological functions were analyzed using GO, KEGG and GSEA enrichment analyses. The hub genes were identified using STRING database, based on which a prognostic model was constructed using LASSO regression. The mutations of the key hub genes were analyzed and their impacts on immunotherapy efficacy was predicted using the cBioPortal platform. RT-qPCR was used to verify the differential expressions of the key hub genes in Wilms tumor. RESULTS: Of the 1612 differentially expressed genes identified in Wilms tumor, 1030 were up-regulated and 582 were down-regulated, involving mainly cell cycle processes and immune responses. Ten hub genes were identified, among which 4 genes (TP53, MED1, CCNB1 and EGF) were closely related to the survival of children with Wilms tumor. A 3-gene prognostic signature was constructed through LASSO regression analysis, and the patients stratified into with high- and low-risk groups based on this signature had significantly different survival outcomes (HR=1.814, log-rank P=0.002). The AUCs of the 3-, 5- and 7-year survival ROC curves of this model were all greater than 0.7. The overall mutations in the key hub genes or the individual mutations in TP53/CCNB1 were strongly correlated with a lower survival rates, and a high TP53 expression was correlated with a poor immunotherapy efficacy. RT-qPCR confirmed that the key hub genes had significant differential expressions in Wilms tumor tissues and cells. CONCLUSION: TP53 gene plays an important role in the Wilms tumor and may potentially serve as a new immunotherapeutic biomarker as well as a therapeutic target.

Prevention of treatment abandonment remains an important challenge to increase survival of Wilms tumor in sub-Saharan Africa: A report from Wilms Africa-CANCaRe Africa.

BACKGROUND: The Wilms Africa studies implemented an adapted Wilm's tumor (WT) treatment protocol in sub-Saharan Africa in two phases. Phase I began with four sites and provided out-of-pocket costs. Phase II expanded the number of sites, but lost funding provision. Objective is to describe the outcomes of Phase II and compare with Phase I. METHODS: Wilms Africa Phase I (n = 4 sites; 2014-2018) and Phase II (n = 8 sites; 2021-2022) used adapted treatment protocols. Funding for families' out-of-pocket costs was provided during Phase I but not Phase II. Eligibility criteria were age less than 16 years and newly diagnosed unilateral WT. We documented patients' outcome at the end of planned first-line treatment categorized as treatment abandonment, death during treatment, and disease-related events (death before treatment, persistent disease, relapse, or progressive disease). Sensitivity analysis compared outcomes in the same four sites. RESULTS: We included 431 patients in Phase I (n = 201) and Phase II (n = 230). The proportion alive without evidence of disease decreased from 69% in Phase I to 54% in Phase II at all sites (p = .002) and 58% at the original four sites (p = .04). Treatment abandonment increased overall from 12% to 26% (p < .001), and was 20% (p = .04) at the original four sites. Disease-related events (5% vs. 6% vs. 6%) and deaths during treatment (14% vs. 14% vs. 17%) were similar. CONCLUSION: Provision of out-of-pocket costs was important to improve patient outcomes at the end of planned first-line treatment in WT. Prevention of treatment abandonment remains an important challenge.

Automated segmentation and volume prediction in pediatric Wilms' tumor CT using nnu-net.

BACKGROUND: Radiologic volumetric evaluation of Wilms' tumor (WT) is an important indicator to guide treatment decisions. However, due to the heterogeneity of the tumors, radiologists have main-guard differences in diagnosis that can lead to misdiagnosis and poor treatment. The aim of this study was to explore whether CT-based outlining of WT foci can be automated using deep learning. METHODS: We included CT intravenous phase images of 105 patients with WT and double-blind outlining of lesions by two radiologists. Then, we trained an automatic segmentation model using nnUnet. The Dice similarity coefficient (DSC) and 95th percentile Hausdorff distance (HD95) were used to assess the performance. Next, we optimized the automatic segmentation results based on the ratio of the three-dimensional diameter of the lesion to improve the performance of volumetric assessment. RESULTS: The DSC and HD95 was 0.83 ± 0.22 and 10.50 ± 8.98 mm. The absolute difference and percentage difference in tumor size was 72.27 ± 134.84 cm3 and 21.08% ± 30.46%. After optimization according to our method, it decreased to 40.22 ± 96.06 cm3 and 10.16% ± 9.70%. CONCLUSION: We introduce a novel method that enhances the accuracy of predicting WT volume by integrating AI automated outlining and 3D tumor diameters. This approach surpasses the accuracy of using AI outcomes alone and has the potential to enhance the clinical evaluation of pediatric patients with WT. By intertwining AI outcomes with clinical data, this method becomes more interpretive and offers promising applications beyond Wilms tumor, extending to other pediatric diseases.

The impact of the route to diagnosis in nephroblastoma.

INTRODUCTION: Wilms tumor (WT) is the most common childhood kidney cancer. It is a rapid growing embryonal tumor in young children and can be diagnosed with and without tumor related symptoms. METHODS: We retrospectively analyzed the route to diagnosis of WT treated prospectively according to the SIOP 93-01/GPOH and 2001/GPOH in Germany between 1993 and 2022. Four routes were defined: diagnosis due to tumor-related symptoms, incidental diagnosis during another disease, diagnosis by preventive examinations, and diagnosis within a surveillance program. For these groups we compared clinical and tumor characteristics and outcome. RESULTS: Of 2549 patients with WT 1822 (71.5%) were diagnosed by tumor-related symptoms, 472 (18.5%) incidentally, 213 (8.4%) by preventive medical examinations, and 42 (1.6%) by surveillance. Age, general health status, tumor volume, and local and overall stage varied significantly between these groups. The youngest patients were those diagnosed by preventive medical examination (mean: 1.70 years). These patients also showed the best general health status. Tumor volume at diagnosis (549 mL) and after preoperative chemotherapy (255 mL) was significantly higher for children with tumor-related symptoms. The highest percentage of local stage I (78.6%) and the lowest percentage of metastatic disease (4.8%) was found in the surveillance group. The outcome of patients was not significantly different, with up to 19.0% relapses in the surveillance group and 3.0% deaths in the group with tumor-related symptoms. CONCLUSION: The route to diagnosis of WT correlates with age, general health status, tumor volume, and stage distribution, but does not impact the outcome of patients. Nonetheless, diagnosis without tumor related symptoms results in lower treatment burden and thus improved quality of life.

Current Realities of Wilms Tumor Burden and Therapy in Ghana.

BACKGROUND: Between 2005 and 2014, Ghana's Wilms tumor (WT) 2-year disease-free survival of 44% trailed behind that of high-income countries. This study aimed to uncover social determinants of health leading to preventable WT death in Ghana. METHODS: WT patient records (2014-2022) at Korle-Bu Teaching Hospital (KBTH; Ghana) were reviewed retrospectively. Demographics, clinical course, tumor characteristics, and survival were evaluated using t-tests, Pearson Chi-square, and multivariate Cox logistic regression. RESULTS: Of 127 patients identified, 65 were female. Median age was 44 months [IQR 25-66]. Forty-eight patients (38%) presented with distant metastasis (75% lung, 25% liver), which associated with hypoalbuminemia (p = 0.009), caregiver informal employment (p = 0.04), and larger tumors (p = 0.002). Despite neoadjuvant chemotherapy shrinking 84% of tumors, larger initial size associated with incomplete resection (p = 0.046). Of 110 nephrectomies, 31 patients had residual disease, negatively impacting survival (p = 2.7 × 10-5). Twenty-two patients (17%) abandoned treatment (45% before nephrectomy; 55% after nephrectomy), with seven patients ultimately lost to follow-up (LTFU). Decedents represented 43% of stage IV patients compared to 28% in other stages. Event-free survival (EFS) was 60% at 4 years with overall survival (OS) at 67%. CONCLUSIONS: Although Ghana's WT survival has improved, informal employment and distance from KBTH predisposed patients to delayed referral, greater tumor burden, hypoalbuminemia, and lower survival. TYPE OF STUDY: Prognosis Study. LEVEL OF EVIDENCE: II.

Surgical Management of Wilms Tumors with Intravenous Extension: A Multicenter Analysis of Clinical Management with Technical Insights.

BACKGROUND: About 5% of Wilms tumors present with vascular extension, which sometimes extends to the right atrium. Vascular extension does not affect the prognosis, but impacts the surgical strategy, which is complex and not fully standardized. Our goal is to identify elements of successful surgical management of Wilms tumors with vascular extensions. PATIENTS AND METHODS: A retrospective study of pediatric Wilms tumors treated at three sites (January 1999-June 2019) was conducted. The inclusion criterion was the presence of a renal vein and vena cava thrombus at diagnosis. Tumor stage, pre and postoperative treatment, preoperative imaging, operative report, pathology, operative complications, and follow-up data were reviewed. RESULTS: Of the 696 pediatric patients with Wilms tumors, 69 (9.9%) met the inclusion criterion. In total, 24 patients (37.5%) had a right atrial extension and two presented with Budd-Chiari syndrome at diagnosis. Two died at diagnosis owing to pulmonary embolism. All patients received neoadjuvant chemotherapy and thrombus regressed in 35.6% of cases. Overall, 14 patients had persistent intra-atrial thrombus extension (58%) and underwent cardiopulmonary bypass. Most thrombi (72%) were removed intact with nephrectomy. Massive intraoperative bleeding occurred during three procedures. Postoperative renal insufficiency was identified as a risk factor for patient survival (p = 0.01). With a median follow-up of 9 years (range: 0.5-20 years), overall survival was 89% and event-free survival was 78%. CONCLUSIONS: Neoadjuvant chemotherapy with proper surgical strategy resulted in a survival rate comparable to that of children with Wilms tumors without intravascular extension. Clinicians should be aware that postoperative renal insufficiency is associated with worse survival outcomes.

Bilateral Wilms tumor with anaplasia: A report from the Children's Oncology Group Study AREN0534.

INTRODUCTION: The purpose of this study is to examine the outcomes in children with anaplastic bilateral Wilms tumor (BWT) from study AREN0534 in order to define potential prognostic factors and areas to target in future clinical trials. METHODS: Demographic and clinical data from AREN0534 study patients with anaplasia (focal anaplasia [FA], or diffuse anaplasia [DA]) were compared. Event-free survival (EFS) and overall survival (OS) were reported using Kaplan-Meier estimation with 95% confidence bands, and differences in outcomes between FA and DA compared using log-rank tests. The impact of margin status was analyzed. RESULTS: Twenty-seven children who enrolled on AREN0534 had evidence of anaplasia (17 DA, 10 FA) in at least one kidney and were included in this analysis. Twenty-six (96%) had BWT. Nineteen percent had anaplastic histology in both kidneys (four of 17 DA, and one of 10 FA). Forty-six percent with BWT had bilateral nephron-sparing surgery (NSS); one child who went off protocol therapy, eventually required bilateral completion nephrectomies. Median follow-up for EFS and OS was 8.6 and 8.7 years from enrollment. Four- and 8-year EFS was 53% [95% confidence interval (CI): 34%-83%] for DA; 4-year EFS was 80% [95% CI: 59%-100%], and 8-year EFS 70% [95% CI: 47%-100%] for FA. Three out of 10 children with FA and eight out of 17 children with DA had events. EFS did not differ statistically by margin status (p = .79; HR = 0.88). Among the six children who died (five DA, one FA), all experienced prior relapse or progression within 18 months. CONCLUSION: Events in children with DA/FA in the setting of BWT occurred early. Caution should be taken about interpreting the impact of margin status outcomes in the context of contemporary multimodal therapy. Future targeted investigations in children with BWT and DA/FA are needed.

Effect of miR-590-3p/DKK1 Axis on the Progression of Wilms' Tumour.

BACKGROUND: Wilms' tumour is the most prevalent abdominal malignancy in children. This study focused on the mechanism of the miR-590-3p/Dickkopf 1 (DKK1) axis in Wilms' tumour. METHODS: The mRNA levels of miR-590-3p and DKK1 in 49 pairs of Wilms' tumour pathological specimens and normal tissues were determined using real-time quantitative polymerase chain reaction (RT-qPCR). Wilms' tumour cells' invasion ability and proliferative ability were assessed using a Transwell assay and Cell Counting Kit-8 (CCK-8) assay, respectively. Dual-luciferase assay was performed to evaluate the potential relationship between miR-590-3p and DKK1 in Wilms tumour. Furthermore, a mouse transplanted tumour model was constructed to explore the function of miR-590-3p inhibitor on Wilms' tumour growth in vivo. RESULTS: DKK1 emerged as a target gene of miR-590-3p in Wilms' tumour. DKK1 expression was downregulated (p < 0.01), but miR-590-3p was overexpressed (p < 0.01) in Wilms' tumour tissues compared to normal tissues. miR-590-3p overexpression accelerated Wilms' tumour invasive ability and cell proliferation (p < 0.01). Additionally, DKK1 partially reversed miR-590-3p-induced proliferation (p < 0.05) and invasion ability (p < 0.01). Furthermore, downregulation of miR-590-3p restrained the growth rate of transplanted tumours in nude mice (p < 0.01). CONCLUSIONS: Through the regulation of DKK1, miR-590-3p accelerated the invasion and proliferation of Wilms' tumour. The study suggests that the miR-590-3p/DKK1 axis represents a novel mechanism in Wilms' tumour.

Characterization of Alternative Splicing in High-Risk Wilms' Tumors.

The significant heterogeneity of Wilms' tumors between different patients is thought to arise from genetic and epigenetic distortions that occur during various stages of fetal kidney development in a way that is poorly understood. To address this, we characterized the heterogeneity of alternative mRNA splicing in Wilms' tumors using a publicly available RNAseq dataset of high-risk Wilms' tumors and normal kidney samples. Through Pareto task inference and cell deconvolution, we found that the tumors and normal kidney samples are organized according to progressive stages of kidney development within a triangle-shaped region in latent space, whose vertices, or "archetypes", resemble the cap mesenchyme, the nephrogenic stroma, and epithelial tubular structures of the fetal kidney. We identified a set of genes that are alternatively spliced between tumors located in different regions of latent space and found that many of these genes are associated with the epithelial-to-mesenchymal transition (EMT) and muscle development. Using motif enrichment analysis, we identified putative splicing regulators, some of which are associated with kidney development. Our findings provide new insights into the etiology of Wilms' tumors and suggest that specific splicing mechanisms in early stages of development may contribute to tumor development in different patients.