Current therapy for Wilms' tumor

Dosimetric Advantage of Combined IMRT for Whole Lung and Abdomen Irradiation for Wilms Tumor

Purpose

In patients with Wilms tumor with lung metastases, a cardiac-sparing intensity modulated radiation therapy (CS-IMRT) technique is increasingly being adopted for whole lung irradiation. However, the standard technique for flank and whole abdomen radiation remains 2-dimensional anterioposterior (AP), and overlap at the junction between the whole lung CS-IMRT and abdominal AP fields can result in overdose to normal organs. Here, we compared the dosimetry of patients who received whole lung irradiation and flank or abdominal radiation therapy with CS-IMRT with AP abdominal field (IMRT-AP) versus CS-IMRT with IMRT abdominal field (combined IMRT).

Methods and Materials

We retrospectively reviewed the radiation plans of 2 patients with Wilms tumor who received CS-IMRT and flank or whole abdomen irradiation with a combined IMRT approach. Comparison IMRT-AP plans were generated with equivalent target coverage of 95% receiving the prescribed dose. Maximum doses to normal organs were compared at the junctional overlap.

Results

Overlap at the junction between CS-IMRT and abdominal fields resulted in a significantly lower dose with combined IMRT plans compared with IMRT-AP plan. Differences in maximum doses (in cGy) to normal organs between combined IMRT versus IMRT-AP plans were most significant in the vertebral body (patient 1 = 1277 vs 2065; patient 2 = 1334 vs 2287), lungs (patient 1 = 1298 vs 2081; patient 2 = 1234 vs 1820), spinal cord (patient 1 = 1235 vs 1975; patient 2 = 1345 vs 2253), stomach (patient 1 = 1264 vs 1977; patient 2 = 1118 vs 2062), and liver (patient 1 = 1297 vs 1889; patient 2 = 1334 vs 2237).

Conclusions

The combined IMRT approach for Wilms patients who require whole lung and abdomen irradiation can provide more uniform dose distribution in the junction area and significantly lower doses to normal organs at the junctional overlap.

Outcomes of Wilms tumor therapy in Lilongwe, Malawi, 2016-2021: Successes and ongoing research priorities

INTRODUCTION

Wilms tumor therapy in low- and middle-income countries (LMICs) relies on treatment protocols adapted to resource limitations, but these protocols have rarely been evaluated in real-world settings. Such evaluations are necessary to identify high-impact research priorities for clinical and implementation trials in LMICs. The purpose of this study was to identify highest priority targets for future clinical and implementation trials in sub-Saharan Africa by assessing outcomes of a resource-adapted treatment protocol in Malawi.

METHODS

We conducted a retrospective cohort study of children treated for Wilms tumor with an adapted SIOP-backbone protocol in Lilongwe, Malawi between 2016 and 2021. Survival analysis assessed variables associated with poor outcome with high potential for future research and intervention.

RESULTS

We identified 136 patients, most commonly with stage III (n = 35; 25.7%) or IV disease (n = 35; 25.7%). Two-year event-free survival (EFS) was 54% for stage I/II, 51% for stage III, and 13% for stage IV. A single patient with stage V disease survived to 1 year. Treatment abandonment occurred in 36 (26.5%) patients. Radiotherapy was indicated for 55 (40.4%), among whom three received it. Of these 55 patients, 2-year EFS was 31%. Of 14 patients with persistent metastatic pulmonary disease at the time of nephrectomy, none survived to 2 years. Notable variables independently associated with survival were severe acute malnutrition (hazard ratio [HR]: 1.9), increasing tumor stage (HR: 1.5), and vena cava involvement (HR: 3.1).

CONCLUSION

High-impact targets for clinical and implementation trials in low-resource settings include treatment abandonment, late presentation, and approaches optimized for healthcare systems with persistently unavailable radiotherapy.

Lipid Metabolic Reprogramming in Embryonal Neoplasms with MYCN Amplification

Tumor cells reprogram their metabolism, including glucose, glutamine, nucleotide, lipid, and amino acids to meet their enhanced energy demands, redox balance, and requirement of biosynthetic substrates for uncontrolled cell proliferation. Altered lipid metabolism in cancer provides lipids for rapid membrane biogenesis, generates the energy required for unrestricted cell proliferation, and some of the lipids act as signaling pathway mediators. In this review, we focus on the role of lipid metabolism in embryonal neoplasms with MYCN dysregulation. We specifically review lipid metabolic reactions in neuroblastoma, retinoblastoma, medulloblastoma, Wilms tumor, and rhabdomyosarcoma and the possibility of targeting lipid metabolism. Additionally, the regulation of lipid metabolism by the MYCN oncogene is discussed.

Development of a Machine Learning-Based Prediction Model for Chemotherapy-Induced Myelosuppression in Children with Wilms' Tumor

Purpose: Develop and validate an accessible prediction model using machine learning (ML) to predict the risk of chemotherapy-induced myelosuppression (CIM) in children with Wilms' tumor (WT) before chemotherapy is administered, enabling early preventive management. Methods: A total of 1433 chemotherapy cycles in 437 children with WT who received chemotherapy in our hospital from January 2009 to March 2022 were retrospectively analyzed. Demographic data, clinicopathological characteristics, hematology and blood biochemistry baseline results, and medication information were collected. Six ML algorithms were used to construct prediction models, and the predictive efficacy of these models was evaluated to select the best model to predict the risk of grade ≥ 2 CIM in children with WT. A series of methods, such as the area under the receiver operating characteristic curve (AUROC), the calibration curve, and the decision curve analysis (DCA) were used to test the model's accuracy, discrimination, and clinical practicability. Results: Grade ≥ 2 CIM occurred in 58.5% (839/1433) of chemotherapy cycles. Based on the results of the training and validation cohorts, we finally identified that the extreme gradient boosting (XGB) model has the best predictive efficiency and stability, with an AUROC of up to 0.981 in the training set and up to 0.896 in the test set. In addition, the calibration curve and the DCA showed that the XGB model had the best discrimination and clinical practicability. The variables were ranked according to the feature importance, and the five variables contributing the most to the model were hemoglobin (Hgb), white blood cell count (WBC), alkaline phosphatase, coadministration of highly toxic chemotherapy drugs, and albumin. Conclusions: The incidence of grade ≥ 2 CIM was not low in children with WT, which needs attention. The XGB model was developed to predict the risk of grade ≥ 2 CIM in children with WT for the first time. The model has good predictive performance and stability and has the potential to be translated into clinical applications. Based on this modeling and application approach, the extension of CIM prediction models to other pediatric malignancies could be expected.

Photodynamic Therapy in Complex Therapy of Retroperitoneal Tumors in Children

During the period from 2009 to 2021, 93 patients aged 0–11 years (48 boys and 45 girls) with retroperitoneal tumors were treated. There were 66 patients with nephroblastoma and 27 patients with adrenal neuroblastoma among them. As per treatment strategies, the patients were separated into two groups: the control group and the study group. The control group (comparison) received therapy according to the protocols, whereas the study group consisted of patients who received photodynamic therapy (PDT) in addition to the standard treatment. The control group consists of 47 patients with retroperitoneal tumors, including 35 patients with nephroblastoma and 12 patients with adrenal neuroblastoma. The study group included 46 children: 31 patients with nephroblastoma and 15 patients with adrenal neuroblastoma. The 5-year survival rate in the control group was 74.5%, and it was 91.3% in the study group (p = 0.030). Recurrent tumors developed in 14.9% of the patients in the control group, while in the study group, relapse occurred in 8.7% of the patients (p = 0.357). The PDT used in this study for treatment of retroperitoneal tumors improves the results of surgical treatment. It also appreciably increases the survival rate of patients with retroperitoneal tumors. Overall, PDT is a hopeful antitumor approach and can be effectively used in the complex therapy of retroperitoneal tumors in children.

Kidney disease in very long-term survivors of Wilms tumor: A nationwide cohort study with sibling controls

BACKGROUND

Survival after Wilms tumor has significantly increased and focus on late effects has become increasingly important. However, knowledge about long-term renal function in survivors of Wilms tumor is missing. Our aim was to investigate evidence of kidney disease in 20- or more-year survivors of Wilms tumor in a clinical setting, with siblings as comparisons.

METHODS

In this cross-sectional study, we established a cohort of Danish 20-plus-year survivors of Wilms tumor and siblings as controls. Participants answered a comprehensive health questionnaire supplemented by measurements of estimated glomerular filtration rate (eGFR), urine albumin-to-creatinine ratio, and blood pressure and were categorized according to the chronic kidney disease classification. Multiple linear regression analysis, taking family membership into account, was used to describe the differences in eGFR. Logistic regression analysis was performed to describe risk factors for the development of kidney disease.

RESULTS

We included 99 survivors of Wilms tumor and 38 sibling controls with a median of 37 years of follow-up. The eGFR of Wilms tumor survivors was 13 ml/min/1.73 m² (95% CI -20; -5) lower when compared to sibling control. Evidence of kidney disease, with risk factors as hypertension and diabetes, was found in 19% of the Wilms tumor survivors and 2% developed end-stage renal disease. Ninety-two percent of the Wilms tumor survivors had an eGFR >60 ml/min/1.73² .

CONCLUSION

Long-term Wilms tumor survivors have on average a significantly decreased renal function along with the increased prevalence of kidney disease and end-stage renal disease when compared to sibling controls. Still, most survivors had kidney function within the normal range.

A Nomogram for Predicting Cancer-Specific Survival in Children With Wilms Tumor: A Study Based on SEER Database and External Validation in China

Background

Wilms tumor (WT) is the most common tumor in children. We aim to construct a nomogram to predict the cancer-specific survival (CSS) of WT in children and externally validate in China.

Methods

We downloaded the clinicopathological data of children with WT from 2004 to 2018 in the SEER database. At the same time, we used the clinicopathological data collected previously for all children with WT between 2013 and 2018 at Children's Hospital of Chongqing Medical University (Chongqing, China). We analyzed the difference in survival between the patients in the SEER database and our hospital. Cox regression analysis was used to screen for significant risk factors. Based on these factors, a nomogram was constructed to predict the CSS of children with WT. Calibration curve, concordance index (C-index), the area under the receiver operating curve (AUC) and decision curve analysis (DCA) was used to evaluate the accuracy and reliability of the model.

Results

We included 1,045 children with WT in the SEER database. At the same time, we collected 112 children with WT in our hospital. The Kaplan-Meier curve suggested that children in China with WT had a higher mortality rate than those in the United States. Cox regression analysis revealed that age, lymph node density (LND), and tumor stage were significant prognostic factors for the patients in the SEER database. However, the patients in our hospital only confirmed that the tumor stage and the number of positive regional lymph nodes were significant factors. The prediction model established by the SEER database had been validated internally and externally to prove that it had good accuracy and reliability.

Conclusion

We have constructed a survival prognosis prediction model for children with WT, which has been validated internally and externally to prove accuracy and reliability.

Knockdown of lncRNA HAGLROS inhibits metastasis and promotes apoptosis in nephroblastoma cells by inhibition of autophagy

Nephroblastoma, or Wilms tumor, is a primary renal malignant tumor that easily occurs in children. Previous studies have revealed the regulatory functions of LncRNA in nephroblastoma. LncRNA HAGLROS functions as a tumor promotor in various cancers including hepatocellular carcinoma, ovarian cancer and colorectal cancer. In this study, the HAGLROS expression in nephroblastoma cells was assayed through qRT-PCR. Cell proliferation assessment employed CCK-8. Moreover, the migration and invasion of cells were examined separately through wound healing and transwell assay. Moreover, flow cytometric analysis and Western blot assay were applied to evaluate cell apoptosis. Rapamycin and 3-methyladenine were used to serve as autophagy activator or inhibitor, respectively. In addition, autophagy was identified by immunofluorescence staining and Western blot analysis. Experiment results showed that HAGLROS expressed highly in nephroblastoma cell lines. HAGLROS knockdown prevented cells from proliferating, and also showed suppressive impact on migration and invasion in HFWT cells. In addition, knockdown of HAGLROS showed a facilitative effect on apoptosis and an inhibitory effect on autophagy. Stimulation of autophagy alleviated HAGLROS silencing-induced apoptosis, while inhibition of autophagy reversed the effect in nephroblastoma cells. In summary, our results revealed that HAGLROS executed an oncogenic role in the progress of nephroblastoma, offering a new perspective on the strategy for nephroblastoma therapy.

Virtual Resection: A New Tool for Preparing for Nephron-Sparing Surgery in Wilms Tumor Patients

Nephron-sparing surgery (NSS) in Wilms tumor (WT) patients is a surgically challenging procedure used in highly selective cases only. Virtual resections can be used for preoperative planning of NSS to estimate the remnant renal volume (RRV) and to virtually mimic radical tumor resection. In this single-center evaluation study, virtual resection for NSS planning and the user experience were evaluated. Virtual resection was performed in nine WT patient cases by two pediatric surgeons and one pediatric urologist. Pre- and postoperative MRI scans were used for 3D visualization. The virtual RRV was acquired after performing virtual resection and a questionnaire was used to assess the ease of use. The actual RRV was derived from the postoperative 3D visualization and compared with the derived virtual RRV. Virtual resection resulted in virtual RRVs that matched nearly perfectly with the actual RRVs. According to the questionnaire, virtual resection appeared to be straightforward and was not considered to be difficult. This study demonstrated the potential of virtual resection as a new planning tool to estimate the RRV after NSS in WT patients. Future research should further evaluate the clinical relevance of virtual resection by relating it to surgical outcome.

Genitourinary Tract Tumors in Children: An Update

BACKGROUND

Genitourinary tract tumors in children are less common than in adults. Most of these tumors have different genetic backgrounds, clinical presentation, and oncologic behavior than their adult counterpart. As a result of low prevalence in children, some of the treatment approaches and recommendations are based on treatment experience in adult patients. However, thanks to scientific and technological development, survival rates have risen considerably.

OBJECTIVE

This paper presents a review of the principal features of the tumors involving the genitourinary tract in children and an update in genetic background, diagnosis, and treatment.

METHODS

A narrative review was performed on published literature about genitourinary tract tumors in pediatric patients. Papers presented in English and Spanish literature were reviewed. PubMed, Science Direct, and SciELO databases were used to collect information and present this article.

RESULTS

Kidney tumors are the most common type of genitourinary tumors in children. Among those, Wilms tumor represents the majority of cases and shows the successful work of clinical trial groups studying this tumor type. Other tumors involving the genitourinary tract in children include Rhabdomyosarcoma, Transitional cell carcinoma, Testicular, and Adrenal tumors.

CONCLUSION

Genitourinary tract tumors in children represent significant morbidity and economic burden, so awareness in early diagnosis represents improvement in treatment, clinical, and oncological outcomes.

Fasting Intervention for Children With Unilateral Renal Tumors to Reduce Toxicity

Childhood renal tumors account for around 6% of all childhood cancers and 90% of these cases are Wilms tumor. In Europe, the SIOP-RTSG approach is considered standard of care and has resulted in five-year survival rates of over 90%. Efforts to decrease toxicity are now being pursued. Short-term fasting (STF), a short but strong reduction in calorie-intake, is associated with improved fitness, enhanced coping with acute physical stress and a lower risk of age-associated diseases. STF temporarily reduces growth to boost resilience, maintenance, and defense-mechanisms, by which toxic side-effects of (oxidative) damage and inflammation are largely prevented. Renal surgery for Wilms tumor carries a risk of acute kidney injury (AKI) and pediatric patients that had an episode of AKI are at increased risk for developing chronic renal disease. STF could mitigate surgery-induced stress and could further improve outcomes. We aim to investigate the effect of STF on renal function recovery after renal tumor surgery by conducting a single-center, prospective, randomized, non-blinded, intervention study. Children diagnosed with a unilateral renal tumor and opting for curative treatment are eligible for inclusion. The main study objective is to investigate the potential decrease in occurrence of AKI due to STF. Secondary objectives include renal function recovery, child's wellbeing, physical functioning, and feasibility of and adherence to STF in children with cancer.

Staging childhood cancers in Europe: Application of the Toronto stage principles for neuroblastoma and Wilms tumour. The JARC pilot study

BACKGROUND

The 'Toronto consensus principles and guidelines' (TG) provided paediatric-specific staging system affordable by population-based cancer registries (CRs). Within the European Rare Cancers Joint Action, a pilot study of the application of TG for childhood cancer (CC) was conducted to test the ability of CRs to reconstruct stage, describe stage across countries and assess survival by stage.

PROCEDURE

Twenty-five CRs representing 15 countries contributed data on a representative sample of patients with neuroblastoma (NB) and Wilms tumour (WT) <15 years, diagnosed between 2000 and 2016. Outcome was calculated by Kaplan-Meier method and by Cox regression model.

RESULTS

Stage was reconstructed for 95% of cases. Around half of the children had localised or locoregional disease at diagnosis. The proportion of metastatic cases was 38% for NB and 13% for WT. Three-year survival was >90% for locoregional cases both of NB and WT, 58% for NB M-stage and 77% for WT stage-IV. Older age was associated with more advanced stage.

CONCLUSIONS

European CRs were able to reconstruct stage according to the TG. Stage should be included in the routine collection of variables. Stage information had clear prognostic value and should be used to investigate survival variations between countries or over time.

Non-coding RNAs in Wilms' tumor: biological function, mechanism, and clinical implications

Non-coding RNAs are involved with maintenance and regulation of physiological mechanisms and are involved in pathological processes, such as cancer. Among the small ncRNAs, miRNAs are the most explored in tumorigenesis, metastasis development, and resistance to chemotherapy. These small molecules of ~ 22 nucleotides are modulated during early renal development, involved in the regulation of gene expression and Wilms' tumor progression. Wilms' tumors are embryonic tumors with few mutations and complex epigenetic dysregulation. In recent years, the small ncRNAs have been explored as potentially related both in physiological development and in the tumorigenesis of several types of cancer. Besides, genes regulated by miRNAs are related to biological pathways as PI3K, Wnt, TGF-β, and Hippo signaling pathways, among others, which may be involved with the underlying mechanisms of resistance to chemotherapy, and in this way, it has emerged as potential targets for cancer therapies, including for Wilms' tumors.

Many faces of Wilms Tumor: Recent advances and future directions

Background

Wilms’ tumor (WT) is the most frequently occurring paediatric renal tumor and is one of the most treatment-responsive tumors. A tumor-suppressor gene and other genetic abnormalities have been implicated in its etiology. In addition, patients with many congenital anomalies, such as Beckwith-Wiedemann syndrome, WAGR syndrome and Denys-Drash syndrome, have an increased risk of WT.

Methods and results

Two large collaborative groups – National Wilms Tumor Study Group (NWTSG)/Children's Oncology Group (COG) and The International Society of Paediatric Oncology (SIOP) have laid down the guidelines for standardized treatment of WT, though differing in the diagnostic and therapeutic approach. The major difference in the two guidelines is the timing of surgery: SIOP recommends using preoperative chemotherapy and NWTSG/COG prefers primary surgery before any adjuvant treatments. Both these groups currently aim at intensifying treatment for patients with poor prognosticators while appropriating the therapy to reduce long-term complications for those with favourable prognostic features. As the survival rate has now reached 90%, the primary objectives of the physician are to perform nephron-sparing surgery in selected cases and to reduce the dosage and duration of chemotherapy and radiotherapy in appropriate cases. The purpose of this review is to present current standards of diagnosis and treatment of WT around the world.

Conclusion

Further studies in future should be done to highlight the use of chemotherapy and radiotherapy under risk-stratified strategies. Further improvement in survival of these children can only be achieved by increasing awareness, early recognition, appropriate referral, and a multidisciplinary approach.

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o Most of the patients with WT have good prognosis.

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o Multimodality treatment and multidisciplinary care are the major contributors for an improved prognosis.

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o Further studies should be done on usage of chemotherapy and radiotherapy under more accurate risk-stratified strategies and to decrease the late effects of surgery.

Outcome of Children with Wilms' Tumor in Developing Countries

Wilms’ tumor is the most common kidney tumor of childhood. The outcome of this malignant tumor has improved due to the improvement of therapeutic strategies. The most important factor in determining the prognosis of these patients is the histopathology subtype of the tumor; unfavorable histopathology is seen in only 11.5% of the patients, which accounts for 52% of deaths. Therefore, the aim of this study was to determine the outcome of children with Wilms’ tumor referred to our hospital over a period of 10 years. This is a retrospective cohort study, and the target population included all patients with Wilms’ tumor referred to Ali Asghar Hospital and were treated according to the National Wilms tumor study 4 (NWTS-4) protocol. All patients’ data were extracted from the medical records of the department. Overall survival and event-free survival (EFS) were analyzed by the Kaplan Mayer method in the SPSS software, version 23. Fifty-two patients (24 male and 28 female patients) with Wilms’ tumor were included. The mean age of the subjects was 40 months. The most common stage among boys and girls was stage II (23.08% and 28.85%, respectively). Our findings revealed that the overall five-year survival of patients was 87±5%; this figure was determined as 100% for boys and 76.8% ± 1.6 for girls (P = 0.018). Our findings show a dramatic improvement in the outcome of children with Wilms’s tumor, and our results are comparable with other results from developed countries. Gender may be an independent prognostic factor of children with Wilms’ tumor.

Investigating Wilms' Tumours Worldwide: A Report of the OxPLORE Collaboration-A Cross-Sectional Observational Study

BACKGROUND

Childhood cancer is neglected within global health. Oxford Pediatrics Linking Oncology Research with Electives describes early outcomes following collaboration between low- and high-income paediatric surgery and oncology centres. The aim of this paper is twofold: to describe the development of a medical student-led research collaboration; and to report on the experience of Wilms' tumour (WT).

METHODS

This cross-sectional observational study is reported as per STROBE guidelines. Collaborating centres included three tertiary hospitals in Tanzania, Rwanda and the UK. Data were submitted by medical students following retrospective patient note review of 2 years using a standardised data collection tool. Primary outcome was survival (point of discharge/death).

RESULTS

There were 104 patients with WT reported across all centres over the study period (Tanzania n = 71, Rwanda n = 26, UK n = 7). Survival was higher in the high-income institution [87% in Tanzania, 92% in Rwanda, 100% in the UK (X² 36.19, p < 0.0001)]. Given the short-term follow-up and retrospective study design, this likely underestimates the true discrepancy. Age at presentation was comparable at the two African sites but lower in the UK (one-way ANOVA, F = 0.2997, p = 0.74). Disease was more advanced in Tanzania at presentation (84% stage III-IV cf. 60% and 57% in Rwanda and UK, respectively, X² 7.57, p = 0.02). All patients had pre-operative chemotherapy, and a majority had nephrectomy. Post-operative morbidity was higher in lower resourced settings (X² 33.72, p < 0.0001). Methodology involving medical students and junior doctors proved time- and cost-effective. This collaboration was a valuable learning experience for students about global research networks.

CONCLUSIONS

This study demonstrates novel research methodology involving medical students collaborating across the global south and global north. The comparison of outcomes advocates, on an institutional level, for development in access to services and multidisciplinary treatment of WT.

Outcome of Children with Stage IV Wilms Tumor - Our Experience of 15 Years

Context:

Stage IV Wilms tumor is associated with poor prognosis, and recent changes in management have been suggested based on genetic markers and response to chemotherapy in this subgroup of patients.

Objective:

The objective was to evaluate the outcomes of children with Stage IV Wilms tumor who were managed with the AIIMS-WT-99 protocol.

Materials and Methods:

All the children with Stage IV Wilms tumor who were managed by us from October 2000 to December 2012 were included in the study. All the patients who had received primary treatment elsewhere were excluded from the study. All patients were managed as per the AIIMS-WT-99 protocol. After appropriate investigations, tumors that were deemed resectable underwent an upfront surgery. Unresectable and inoperable tumors received chemotherapy after cytological confirmation of the diagnosis. Chemotherapy was administered as per the NWTS-5 study. Pulmonary and flank radiotherapy was advised to all patients. Patients with poor response to chemotherapy or with recurrence were managed with an alternative chemotherapy regimen. The outcomes that were assessed the 4-year overall survival (OS) and the 4-year event-free survival (EFS).

Statistical Analysis Used:

Kaplan–Meier survival estimates.

Results:

During the study period, 219 patients with Wilms tumor were treated. Of these, 36 (16.4%) had Stage IV disease, and they formed the study group. The 4-year OS was 48% with a mean survival time of 59 months limited to 115 months (95% confidence interval: 41.3–75.9 months). The 4-year EFS was 42.4%. Patients with liver metastases had a poor outcome, whereas patients with good response to chemotherapy had a good outcome.

Conclusion:

Stage IV Wilms had a poor prognosis, and the survival rates in the index study are lower than those quoted in the literature. Although the exact reason for this poor result eludes us, these patients may benefit from the intensification of chemotherapy.

Wilms tumor in patients with osteopathia striata with cranial sclerosis

Germline pathogenic variants in AMER1 cause osteopathia striata with cranial sclerosis (OSCS: OMIM 300373), an X-linked sclerosing bone disorder. Female heterozygotes exhibit metaphyseal striations in long bones, macrocephaly, cleft palate, and, occasionally, learning disability. Male hemizygotes typically manifest the condition as fetal or neonatal death. Somatically acquired variants in AMER1 are found in neoplastic tissue in 15-30% of patients with Wilms tumor; however, to date, only one individual with OSCS has been reported with a Wilms tumor. Here we present four cases of Wilms tumor in unrelated individuals with OSCS, including the single previously published case. We also report the first case of bilateral Wilms tumor in a patient with OSCS. Tumor tissue analysis showed no clear pattern of histological subtypes. In Beckwith-Wiedemann syndrome, which has a known predisposition to Wilms tumor development, clinical protocols have been developed for tumor surveillance. In the absence of further evidence, we propose a similar protocol for patients with OSCS to be instituted as an initial precautionary approach to tumor surveillance. Further evidence is needed to refine this protocol and to evaluate the possibility of development of other neoplasms later in life, in patients with OSCS.

Development of paediatric non-stage prognosticator guidelines for population-based cancer registries and updates to the 2014 Toronto Paediatric Cancer Stage Guidelines

Population-based cancer registries (PBCRs) generate measures of cancer incidence and survival that are essential for cancer surveillance, research, and cancer control strategies. In 2014, the Toronto Paediatric Cancer Stage Guidelines were developed to standardise how PBCRs collect data on the stage at diagnosis for childhood cancer cases. These guidelines have been implemented in multiple jurisdictions worldwide to facilitate international comparative studies of incidence and outcome. Robust stratification by risk also requires data on key non-stage prognosticators (NSPs). Key experts and stakeholders used a modified Delphi approach to establish principles guiding paediatric cancer NSP data collection. With the use of these principles, recommendations were made on which NSPs should be collected for the major malignancies in children. The 2014 Toronto Stage Guidelines were also reviewed and updated where necessary. Wide adoption of the resultant Paediatric NSP Guidelines and updated Toronto Stage Guidelines will enhance the harmonisation and use of childhood cancer data provided by PBCRs.

Comprehensive analysis of long non‑coding RNA using an associated competitive endogenous RNA network in Wilms tumor

Wilms tumor (WT) is the most common malignant renal neoplasm in children; however, the underlying molecular mechanisms are not well understood. According to the competing endogenous RNA (ceRNA) theory, long non-coding RNAs (lncRNAs) can regulate the expression of target genes by adsorbing microRNAs (miRNAs/miRs). However, the role of lncRNAs in WT has not been fully elucidated. The aim of the present study was to construct a ceRNA network to identify the potential lncRNAs involved in WT. The expression profiles of lncRNAs, miRNAs and mRNAs in 120 WT and six normal tissues were obtained from the Therapeutically Applicable Research to Generate Effective Treatments database. A total of 442 lncRNAs, 214 miRNAs and 4,912 mRNAs were identified as differentially expressed in WT and were enriched in 472 Gene Ontology terms (355 biological processes, 89 cellular components and 29 molecular functions) and 18 Kyoto Encyclopedia of Genes and Genomes pathways. A lncRNA-miRNA-mRNA ceRNA network of WT consisting of with 32 lncRNAs, 14 miRNAs and 158 mRNAs was constructed, based on the bioinformatics analysis of the miR target prediction database and the miRNAcode, miRTarBase and TargetScan databases. Subsequently, three lncRNAs, three miRNAs and 17 mRNAs, which had a significant effect on the overall survival rate of patients with WT, were identified based on the survival analysis. The three lncRNAs were also differentially expressed in the late and early stages of WT and were validated using the GSE66405 dataset obtained from the Gene Expression Omnibus database. In conclusion, the present study generated a specific lncRNA-related ceRNA network of WT, which may provide a novel perspective on the molecular mechanisms underlying the progression and prognosis of the disease.

Botryoid Wilms Tumor in a Neonate Presenting with Fetal Hydronephrosis: A Case Report

Botryoid Wilms tumor, a very rare variant of Wilms tumor, arises from the pelvocalyceal system, and its occurrence in the fetal or neonatal period has never been reported in the literature. Herein, we report an exceedingly rare and challenging case of botryoid Wilms tumor in a neonate who initially presented with fetal hydronephrosis. Postnatal ultrasonography revealed multiple lobulating hypoechoic masses with varying degrees of intralesional vascularity within the dilated pelvocalyceal system. To our knowedge, this is a case report of botryoid Wilms tumor of the youngest child in English literature.

Development and validation of a nomogram for predicting cancer-specific survival in patients with Wilms' tumor

Purpose: The objective of this study was to develop and validate a nomogram for predicting the cancer-specific survival (CSS) in patients with Wilms' tumor (WT).

Methods: Patients with WT diagnosed between 2002 and 2015 in the Surveillance, Epidemiology, and End Results (SEER) database were divided randomly into training and validation cohorts in this study. Multivariate Cox regression analysis was used to screen variables. A Cox proportional-hazards regression model and a nomogram were constructed based on variables that significantly affected the CSS in the training cohort. The nomogram for distinguishing and predicting the CSS was evaluated using the concordance index (C-index), the area under the time-dependent receiver operating characteristic curve (AUC), and calibration plots.

Results: In total, 1631 patients from the SEER database were enrolled, with 1141 categorized into the training cohort and 490 into the validation cohort. All significant variables associated with CSS—age, the number of examined lymph nodes, SEER stage, and tumor size—were included in the nomogram. The C-index values of the nomogram in the training and validation cohorts were 0.746 and 0.703, respectively. The 3-, 5-, and 10-year AUCs were 0.755, 0.749, and 0.724, respectively, in the training cohort, and 0.718, 0.707, and 0.718 in the validation cohort. The calibration plots indicated the nomogram could accurately predict the 3-, 5-, and 10-year CSS.

Conclusions: We have developed and validated the first nomogram for predicting the survival of WT patients. The nomogram is a reliable tool for distinguishing and predicting the CSS in patients with WT. Information provided by the nomogram may help to improve the clinical practices related to WT.

The genetic changes of Wilms tumour

Wilms tumour is the most common renal malignancy of childhood. The disease is curable in the majority of cases, albeit at considerable cost in terms of late treatment-related effects in some children. However, one in ten children with Wilms tumour will die of their disease despite modern treatment approaches. The genetic changes that underpin Wilms tumour have been defined by studies of familial cases and by unbiased DNA sequencing of tumour genomes. Together, these approaches have defined the landscape of cancer genes that are operative in Wilms tumour, many of which are intricately linked to the control of fetal nephrogenesis. Advances in our understanding of the germline and somatic genetic changes that underlie Wilms tumour may translate into better patient outcomes. Improvements in risk stratification have already been seen through the introduction of molecular biomarkers into clinical practice. A host of additional biomarkers are due to undergo clinical validation. Identifying actionable mutations has led to potential new targets, with some novel compounds undergoing testing in early phase trials. Avenues that warrant further exploration include targeting Wilms tumour cancer genes with a non-redundant role in nephrogenesis and targeting the fetal renal transcriptome.

miR-483-5p Targets MKNK1 to Suppress Wilms' Tumor Cell Proliferation and Apoptosis In Vitro and In Vivo

Background

Wilms’ tumor (WT) is the most common type of renal tumor in children and it has high mortality rates. MicroRNAs (miRNAs) are important regulators of cellular differentiation processes that have been discovered to contribute to the development of various kinds of tumors.

Material/Methods

The Wilms’ tumor tissues and adjacent tissues were obtained from 28 patients to quantity miR-483-5p expression level. The miR-483-5p mimics and scrambles were transfected into the human kidney WT cell line GHINK-1 to evaluate the effect of miR-483-5p on Wilms’ tumor cell proliferation and apoptosis in vitro. A total of 18 female BALB/c nu/nu mice were used to further confirm how miR-483-5p affects Wilms’ tumor in vivo.

Results

In the present study, miR-483-5p was identified to be downregulated in Wilms’ tumor tissues compared with the normal adjacent tissues. Additionally, low expression of mir-483-5p was significantly correlated with unfavorable histology subtypes, lymphatic metastasis, and late clinical stage (stage III and IV). Overexpression of miR-483-5p inhibited the proliferation and colony formation of GHINK-1 (Wilms’ tumor) cells compared with the control group due to enhanced cell apoptosis. Furthermore, miR-483-5p upregulated the protein expression level of caspase-3. Finally, MAP kinase-interacting serine/threonine-protein kinase 1 was identified as a direct target of miR-483-5p, which was confirmed by luciferase reporter assay and Western blotting.

Conclusions

MiR-483-5p suppressed WT cell proliferation via inducing apoptosis through targeting MKNK1. This may provide novel insights into the mechanisms underlying WT and a potential therapeutic candidate for the treatment of WT in the future.

Educational Case: Wilms Tumor (Nephroblastoma)

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology. For additional information, and a full list of learning objectives for all three competencies, see http://journals.sagepub.com/doi/10.1177/2374289517715040.

Synchronous Bilateral Wilms Tumor: Five-Year Single-Center Experience with Assessment of Quality of Life

Context:

Synchronous Bilateral Wilms tumor (sBWT).

Aims:

This study aimed to assess the outcome of patients with sBWT treated on SIOP protocol.

Settings and Design:

Retrospective and prospective randomized study.

Subjects and Methods:

SIOP 93-01 protocol was used to study nine patients of sBWT in a single center and followed up over a period from 2 to 5 years.

Statistical Analysis Used:

Unpaired t-test and Mann–Whitney U-test were used for analysis.

Results:

Of nine patients, six were included in the study as three patients lost to follow-up. Among the six patients, there were four girls and two boys with a median age of 2 years. Mean regression in the size of tumor was 87% in four out of six patients. Tumor with unfavorable histology showed 32% response (ratio of favorable: unfavorable histology 2:1). Event-free survival rate was 81.3% and overall survival was 90% over 2–5 years. Recurrence was seen in two patients of whom one had Denys–Drash syndrome. Mean DTPA glomerular filtration rate was 91.4/ml/min/1.73 m² preoperatively and that of 3 months after completion of treatment was 84/ml/min/1.73 m². Health-related quality of life (HRQOL) using Pediatric Quality of Life Inventory and Lansky Play Performance Scale revealed significant improvement results of all functioning domains such as physical, social, emotional, and school subscales with P < 0.05 and performance scale (P < 0.04).

Conclusions:

We suggest SIOP protocol for sBWT and bilateral nephron-sparing surgery in two stages. However, long-term follow-up is required to assess the ultimate renal function outcome. HRQOL is an essential guide in improving the conditions of pediatric cancer survivors.

Imaging of Unusual Renal Tumors

PURPOSE OF REVIEW

Renal masses are a wide entity and a common finding in clinical practice. Detection of these masses has increased in the last years, yet mortality rates have slightly decreased.

RECENT FINDINGS

According to the World Health Organization classification, there are 8 types, 51 subtypes, and a lot more subsequent subclassifications of renal tumors. Histopathological analysis should always be assessed for final diagnosis of theses tumors. However, imaging can be an important diagnostic guidance. The most common diagnoses of renal tumor are clear cell carcinoma, papillary renal cell carcinoma, angiomyolipoma, and transitional cell carcinoma. Nonetheless, a considerable variety of particular tumors can arise from the kidney, challenging the expertise of radiologists and urologists on this subject. The awareness of these unusual entities is vital for professionals working at a complex medical facility with greater volume of patients. We hereby present uncommon renal tumors and its pathological and radiological features.

Determining the optimal cutoff point for lymph node density and its impact on overall survival in children with Wilms' tumor

Objective

Previous studies showed that the lymph node density (LND) was a predictor of survival in Wilms’ tumor (WT). However, the optimal LND cutoff point is controversial due to methodological shortcomings of previous studies, and no studies have shown the effect of LND on survival in children with WT. The purpose of this study was to remedy this situation.

Methods

We identified 376 children with WT. LND cutoff point was determined using the median value, the X-tile program, the survival-tree algorithm, and the time-dependent ROC curve analysis. Survival functions were estimated by the Kaplan–Meier method. We used Cox regression analysis to determine the impact of LND on survival. Smooth curve fitting between relative mortality risk and LND was performed.

Results

The LND cutoff point was 0.44, 0.65, 0.65, and 0.64 according to the median value, the X-tile program, the survival-tree algorithm, and the time-dependent ROC curve analysis, respectively. The 5-, 10-, and 20-year overall survival rates were 86.9%, 86.9%, and 84.7%, respectively, in the <0.44 group and 81.3%, 80.3%, and 80.3%, respectively, in the ≥0.44 group. Survival did not differ significantly between the two groups (P=0.185). The 5-, 10-, and 20-year overall survival rates were 87.8%, 87.8%, and 86.0%, respectively, in the < 0.65 or < 0.64 group and 76.5%, 75.1%, and 75.1%, respectively, in the ≥ 0.65 or ≥ 0.64 group. Children with the high LND had a significantly worse survival (P=0.011) if 0.64 or 0.65 was used for the stratification. LND was a significant predictor for overall survival in the multivariate Cox regression analysis (HR =1.797; 95% CI, 1.043–3.097; P=0.035). Smooth curve fitting suggested that the risk of mortality tended to be ascending with the increase in LND in general.

Conclusion

The three methods including the X-tile program, the survival-tree algorithm, and the time-dependent receiver operating characteristic (ROC) curve analysis are equivalent in their ability to stratify patients and clearly better than the median method. The results showed that the optimal LND cutoff point was around 0.65 and the LND was a reliable predictor of overall survival in children with WT.

Lymph node imaging of pediatric renal and suprarenal malignancies

Pediatric renal and suprarenal cancers are relatively rare malignancies, but are not without significant consequence to both the patient and caretakers. These tumors are often found incidentally and present as large abdominal masses. Standard of care management involves surgical excision of the mass, but contemporary treatment guidelines advocate for use of neoadjuvant or adjuvant chemotherapy for advanced stage disease, such as those cases with lymph node involvement (LNI). However, LNI detection is based primarily on surgical pathology and performing extended lymph node dissection can add significant morbidity to a surgical case. In this review, we focus on the use and performance of imaging modalities to detect LNI in Wilms’ tumor (WT), neuroblastoma, and pediatric renal cell carcinoma (RCC). We report on how imaging impacts management of these cases and the clinical implications of LNI. A literature search was conducted for studies published on imaging-based detection of LNI in pediatric renal and suprarenal cancers. Further review focused on surgical and medical management of those cases with suspected LNI. Current imaging protocols assisting in diagnosis and staging of pediatric renal and suprarenal cancers are generally limited to abdominal ultrasound and cross-sectional imaging, mainly computed tomography (CT). Recent research has investigated the role of more advance modalities, such as magnetic resonance imaging (MRI) and positron emission tomography (PET), in the management of these malignancies. Special consideration must be made for pediatric patients who are more vulnerable to ionizing radiation and have characteristic imaging features different from adult controls. Management of pediatric renal and suprarenal cancers is influenced by LNI, but the rarity of these conditions has limited the volume of clinical research regarding imaging-based staging. As such, standardized criteria for LNI on imaging are lacking. Nevertheless, advanced imaging modalities are being investigated and potentially represent more accurate and safer options.

Minimally Invasive Approaches to Pediatric Solid Tumors

Over the last decade, driven in part by the favorable adult experience and a crescendoing number of case series and retrospective reports in the pediatric surgical literature, minimally invasive surgical (MIS) approaches are increasingly used as adjunctive or definitive surgical treatments for an ever-expanding list of pediatric tumors. Although most current treatment protocols lack surgical guidelines regarding the use of MIS, this growing body of MIS literature provides a framework for the development of multicenter trial groups, prospective registries, and further centralization of subspecialist services. This article highlights the current available data on MIS approaches to a variety of pediatric malignancies.

Abscessing Infection by Streptococcus mitis Mimicking Metastatic Lesions in a 5-Year-Old Girl With Nephroblastoma: A Case Report

Streptococcus mitis is a common pathogen causing infections in oncological patients. However, cases of abscesses caused by Streptococcus mitis in oncological patients have not been reported so far. We report on 5-year-old child with nephroblastoma and pulmonary and hepatic metastases at diagnosis who went into complete remission undergoing chemotherapy and nephrectomy, and who developed new round lesions in liver and lungs under continuous chemotherapy suggestive of new metastases. Biopsy of the lesions revealed abscesses with detection of Streptococcus mitis. The child was successfully treated with antibiotics, finished chemotherapy per protocol and has been in complete remission for 14 months. Infectious lesions involving organs of typical metastatic dissemination can easily be misdiagnosed as metastases, especially in the absence of symptoms. Histologic proof of lesions suspicious of metastases is mandatory if it leads to a change of prognosis and therapy. Streptococcus mitis can be a causative organism of pulmonary and hepatic abscesses in oncological patients.

Association between loss of heterozygosity of chromosome 16q and survival in Wilms' tumor: A meta-analysis

BACKGROUND

Wilms' tumor (WT) is the most common pediatric renal tumor. Despite its high survival rate, the potential prognostic factors should further be studied to reduce the intensity of the treatment. A few studies have found LOH of 16q is associated with worse survival in patients with WT, but it is still contradictory. This study aimed to performed a meta-analysis to clarify this.

METHODS

Databases including the Wanfang, PubMed, Chinese National Knowledge Infrastructure, Embase, and Cochrane Library databases were searched July 2018. The meta-analysis was done using Stata (version 14.0). Publication bias was evaluated by funnel plots, Begg's test, and Egger's test. The trim-and-fill method was applied if significant publication bias existed. Sensitivity analysis was performed to evaluate the stability of the results.

RESULTS

This meta-analysis identified 9 cohort studies encompassing 3266 cases. The pooled relative risk when comparing LOH of 16q groups with control groups was 2.22 [95% confidence interval (CI) = 1.64-3.00, P < 0.001], and the pooled hazard ratio was 1.92 (95%CI = 1.32-2.80, P = 0.001). The results were stable after correcting for publication bias and performing a leave-one-out sensitivity analysis.

CONCLUSIONS

This meta-analysis indicated that LOH of 16q was significantly associated with worse survival in WT. Further studies need to identify this conclusion because the overall quality of the included studies is not high, investigate the impact of LOH of 16q on the survival of WT patients in different subgroups and identify better treatments for WT patients with LOH of 16q in order to lengthen their survival.

Case report: Diffuse hyperplastic perilobar nephroblastomatosis complicated by a unilateral Wilms tumour: diagnosis, treatment and follow-up

Background

Nephroblastomatosis is an uncommon pathologic process characterized by the presence of persistent embryonic nephrogenic rests. Progression to Wilms tumour occurs in an estimated 35% of patients. Cure rates are based on histologic findings and disease stage and have improved from 10% in the 1920s to over 90% today.

Case presentation

We report a case of a 9-month-old female presenting with a 2-month history of abdominal distension. Ultrasonographic and computed tomographic assessments demonstrated features consistent with bilateral, diffuse, hyperplastic perilobar nephroblastomatosis (DHPLNB) for which she underwent chemotherapy. Magnetic resonance imaging 6 weeks following commencement of chemotherapy revealed a mass concerning for unilateral Wilms tumor for which she underwent partial nephrectomy. Pathology confirmed DHPLNB with a unilateral Wilms tumor.

Conclusion

3.5 year radiographic follow up demonstrates complete recovery. To our knowledge, there are no similar cases with imaging depiction recently published. With potential for malignant transformation into Wilms tumour and low survival rate for late diagnosed Wilms tumors, it is important to recognize nephroblastomatosis early, both clinically and radiographically to improve overall patient prognosis.

Cancer Stem Cells are Regulated by STAT3 Signalling in Wilms Tumour

The survival rates associated with Wilms tumour (WT) remain dismal despite advancements in detection and treatment strategies. Cancer stem cells (CSCs) are correlated with the initiation, recurrence and metastasis of tumours, but its impact on Wilms cancer stem cell (WCSC) maintenance remains unclear. In this study, CD133+ cells were successfully isolated from a single-cell suspension of the G401 Wilms tumour cell line using magnetic activated cell sorting (MACS). Signal transducers and activators of transcription 3 (STAT3) has been implicated in tumorigenesis, but its contribution to the metastatic progression of WCSCs has not been investigated. Here, we show that STAT3 is overexpressed in WCSCs. Activation of STAT3 in WCSCs initiated a forward feedback loop that was responsible for mediating the aggressive malignant character of Wilms tumour cells in vitro and in vivo. Treatment of CD133+ cells with stattic, a STAT3 inhibitor, also inhibited tumour formation and progression in xenograft animal models in vivo. Collectively, these studies revealed a critical role of STAT3 signalling in WCSC proliferation and motility and a role for CD133 in cancer stem-like cell function, providing evidence for CD133 as a potential therapeutic target in Wilms tumour.

The impact of the lymph node density on overall survival in patients with Wilms' tumor: a SEER analysis

Objective

The objective of this study was to determine the impact of the lymph node density (LND) on overall survival of patients with Wilms’ tumor (WT) using the Surveillance, Epidemiology, and End Results (SEER) database.

Methods

Data from the SEER database were extracted from patients with WT in whom the LND could be obtained. Patients were divided into a low LND group and high LND group. Survival curves based on the LND stratification were plotted using the Kaplan–Meier method and compared with the log-rank test. The impact of prognostic factors on overall survival was analyzed using Cox regression models.

Results

A total of 1,924 patients were identified from the database. Overall survival for the low LND group at 5, 10, and 20 years was significantly better than the high LND group (5-year survival: 94.1% vs 81.4%; 10-year survival: 92.6% vs 80.8%; 20-year survival: 90.6% vs 79.1%; P<0.001). In multivariate analysis, LND was a significant predictor of overall survival, regardless of whether it was a categorical variable or a continuous variable. Other significant predictors included age, race, SEER stage, and tumor laterality.

Conclusion

LND was a significant risk factor for overall survival of patients with WT. LND may provide a better prediction of the prognosis of WT patients and may be helpful for designing better treatments.

Cecal Volvulus following a Right Nephrectomy for Wilms' Tumor: Should We Need to Close the Lateral Peritoneum?

Wilms' tumor (WT) accounts for 90% of all pediatric renal malignant tumors. The most common postoperative complication based on the National Wilms' Tumor Study is small bowel obstruction. We report on a 2-year-old girl with postoperative bowel obstruction following a right nephrectomy for WT. The patient was reintervened 48 hours after surgery and a cecal volvulus was found. Here, we will describe possible causes of this postoperative complication and discuss management.

HMGA2 overexpression predicts relapse susceptibility of blastemal Wilms tumor patients

Wilms tumor (WT) is an embryonal malignant neoplasm of the kidney that accounts for 6-7% of all childhood cancers. WT seems to derive from multipotent embryonic renal stem cells that have failed to differentiate properly. Since mechanisms underlying WT tumorigenesis remain largely unknown, the aim of this study was to explore the expression of embryonic stem cell (ESC) markers in samples of WT patients after chemotherapy treatment SIOP protocol, as the gene expression patterns of ESC are like those of most cancer cells. We found that expression of ESC markers is heterogeneous, and depends on histological WT components. Interestingly, among ESC markers, HMGA2 was expressed significantly stronger in the blastemal component than in the stromal and the normal kidney. Moreover, two subsets of patients of WT blastemal type were identified, depending on the expression levels of HMGA2. High HMGA2 expression levels were significantly associated with a higher proliferation rate (p=0.0345) and worse patient prognosis (p=0.0289). The expression of HMGA2 was a stage-independent factor of clinical outcome in blastemal WT patients. Our multivariate analyses demonstrated the association between LIN28B-LET7A-HMGA2 expression, and the positive correlation between HMGA2 and SLUG expression (p=0.0358) in blastemal WT components. In addition, patients with a poor prognosis and high HMGA2 expression presented high levels of MDR3 (multidrug resistance transporter). Our findings suggest that HMGA2 plays a prominent role in the pathogenesis of a subset of blastemal WT, strongly associated with relapse and resistance to chemotherapy.

Identification of differentially expressed inflammatory factors in Wilms tumors and their association with patient outcomes

The present study aimed to identify differentially expressed inflammatory factors observed in Wilms tumors (WT), and to investigate the association of these factors with clinical stage, pathological type, lymph node metastasis and vascular involvement of WT. Surface-enhanced laser desorption/ionization-time of flight mass spectrometry was performed to screen differentially expressed proteins among WT and normal tissue pairs. Upregulated proteins in WT were separated and purified by solid phase extraction and Tricine SDS-PAGE, respectively. Following in-gel digestion, the peptide mixture was subjected to liquid chromatography mass spectrometry to identify proteins on the basis of their amino acid sequences. Immunohistochemistry was used to confirm the expression of differentially expressed inflammatory proteins. Of the proteins that were upregulated in WT, two proteins with mass/charge (m/z) ratio of 12,138 and 13,462 were identified as macrophage migration inhibitory factor (MIF) and C-X-C motif ligand 7 (CXCL7) chemokine, respectively. The expression of these two proteins was increased in WT compared with adjacent normal tissues and normal renal tissues, and increased with increasing clinical stage. In addition, their expression was significantly increased in patients with unfavorable pathological type, lymph node metastasis and vascular involvement compared with the groups with favorable type, and without lymph node metastasis or vascular involvement (P<0.05). Increased pro-inflammatory MIF and CXCL7 expression in WT is closely associated with the clinical stage, pathological type, lymph node metastasis and vascular involvement, and may represent biomarkers for the clinical diagnosis of WT.

Pharmacologic Inhibition of β-Catenin With Pyrvinium Inhibits Murine and Human Models of Wilms Tumor

Wilms tumor (WT) is the most common renal malignancy in children and the fourth most common pediatric solid malignancy in the US. Although the mechanisms underlying the WT biology are complex, these tumors most often demonstrate activation of the canonical Wnt/β-catenin pathway. We and others have shown that constitutive activation of β-catenin restricted to the renal epithelium is sufficient to induce primitive renal epithelial tumors, which resemble human WT. Here we demonstrate that pharmacologic inhibition of β-catenin gene transcription with pyrvinium inhibits tumor growth and metastatic progression in a murine model of WT. Cellular invasion is significantly inhibited in both murine WT-like and human WT cells and is accompanied by downregulation of the oncogenes Myc and Birc5 (survivin). Our studies provide proof of the concept that the canonical Wnt/β-catenin pathway may be a novel therapeutic target in the management of WT.

Congenital mesoblastic nephroma 50 years after its recognition: A narrative review

Congenital mesoblastic nephroma (CMN) is a rare pediatric renal tumor with low malignant potential that most commonly occurs early in infancy. Treatment strategies are based on the few published CMN series, while a significant number of CMN patients have been described in case reports. The aim of this narrative review was to create an up-to-date overview of the literature. Complete surgical removal is curative in most cases. The risk of treatment-related mortality (both surgery- and chemotherapy-related) is relatively high in the first weeks of life, indicating that these young patients deserve special attention with respect to timing and type of treatment.

Management of Wilms Tumor: ICMR Consensus Document

Wilms tumor (WT) is the most common renal tumor of childhood. Although multidisciplinary care including surgery, chemotherapy and radiotherapy have greatly improved the survival rates in WT, there is a scope for further improvement in India and other resource-poor settings. In resource-limited settings, the majority of patients present with large tumors, which may either be unresectable or risky to resect; making preoperative chemotherapy followed by delayed surgery the preferred approach. Histology and staging are used for risk stratification. The imaging procedure of choice is Contrast Enhanced CT scan (CECT) of thorax/ abdomen and pelvis, which is to be done at presentation, as well as for re-evaluation. Surgery is the cornerstone of treatment in WT and Radical Nephroureterectomy and Lymph node sampling is the procedure of choice, to be performed at week 5 in Non Metastatic WT and week 7 in Metastatic WT. WT is an extremely chemosensitive and radiosensitive tumor. Preoperative chemotherapy for Non Metastatic WT consists of 4 wk of Vincristine /Actinomycin and 6 wk of Vincristine /Actinomycin/ Adriamycin for Metastatic WT, with post-operative chemotherapy depending on stage and histology. Radiation therapy is recommended mainly in Stage III and Stage IV WT, with other indications given in the text. Other recommendations, such as treatment of WT in special situations and for supportive care are also detailed in the text.

Functional KRAS mutations and a potential role for PI3K/AKT activation in Wilms tumors

Wilms tumor (WT) is the most common renal neoplasm of childhood and affects 1 in 10 000 children aged less than 15 years. These embryonal tumors are thought to arise from primitive nephrogenic rests that derive from the metanephric mesenchyme during kidney development and are characterized partly by increased Wnt/β-catenin signaling. We previously showed that coordinate activation of Ras and β-catenin accelerates the growth and metastatic progression of a murine WT model. Here, we show that activating KRAS mutations can be found in human WT. In addition, high levels of phosphorylated AKT are present in the majority of WT. We further show in a mouse model and in renal epithelial cells that Ras cooperates with β-catenin to drive metastatic disease progression and promotes in vitro tumor cell growth, migration, and colony formation in soft agar. Cellular transformation and metastatic disease progression of WT cells are in part dependent on PI3K/AKT activation and are inhibited via pharmacological inhibition of this pathway. Our studies suggest both KRAS mutations and AKT activation are present in WT and may represent novel therapeutic targets for this disease.

The prognostic significance of hypertension at diagnosis in children with wilms tumor

Objectives:

To determine the prognostic effect of hypertension at diagnosis on outcomes of children with Wilms tumor (WT).

Methods:

A single center retrospective analysis was conducted on 85 consecutive children with WT diagnosed between January 2000 and August 2013. Patients were classified as hypertensive or normotensive at diagnosis. Overall survival (OS) and progression-free survival (PFS) were estimated using the Kaplan-Meier method. Cox regression was used to determine the predictive significance of hypertension and other clinical factors.

Results:

Seventy-one patients had complete data. Of this, 25 (35.2%) were hypertensive and 46 (64.8%) normotensive with corresponding remission rates of 56.0% versus 82.6%, p=0.032; and death as first event of 7% versus 0%, p=0.004. The 5-year OS in the hypertensive versus normotensive patients were (67.1±10.3% versus 89.6±4.9%, p=0.009) and the corresponding 5-year PFS were (53.4±10.4% versus 79.1±6.2%, p=0.007). With univariate analysis, hypertension and local stage were predictors of OS (p=0.012 and p=0.029) and PFS (p=0.030 and p=0.008). In the multivariate analysis, hypertension, local stage, and histopathology were identified as independent prognostic factors of OS (p=0.004, p=0.034, and p=0.038); and hypertension and local stage as prognostic for PFS (p=0.010 and p=0.012).

Conclusion:

Hypertension at diagnosis is a prognostic predictor of poor outcome in WT and may signify tumor resistance.

Activation of the Wnt/β-catenin pathway is common in wilms tumor, but rarely through β-catenin mutation and APC promoter methylation

PURPOSE

The Wnt/β-catenin pathway is known to be crucial for the regulation of embryogenesis and cell differentiation, and its constitutive activation is associated with a wide range of malignancies. There are two major principles for an activated Wnt/β-catenin pathway. The first is caused by the failure of the destruction complex, mainly due to the decreased expression of the tumor suppressor gene adenomatous polyposis coli (APC); the second is the mutation of the β-catenin (CTNNB1) protein itself. Wilms tumors (WTs) are also thought to be malignancies with a high rate of Wnt/β-catenin pathway activation. The aim of this study was to analyze a large cohort of WT for activated Wnt/β-catenin pathway.

METHODS

The transcription of axis inhibition protein 2 (AXIN2) and APC was analyzed by real-time PCR. Expression was compared with those in healthy renal tissues as a control. Methylation status of the APC promoter was measured by pyrosequencing and correlated with APC expression. Finally, the mutations of CTNNB1 itself were detected by Sanger sequencing.

RESULTS

The analysis was done in a cohort of 103 WTs, treated in our institution. There was a significant overexpression of AXIN2 in WTs (P < 0.0001), with 33 (32 %) tumors showing higher expression (median + 3× SD) than normal kidney tissue. In contrast, the expression of APC as well as its promoter methylation did not differ from control (P = 0.78; P = 0.82). Finally, there were only seven (6.8 %) mutations detectable in CTNNB1, and five out of seven were seen in WTs with AXIN2 overexpression.

CONCLUSION

The finding that AXIN2, one of the major Wnt target genes, is overexpressed in our cohort of WTs, is indicative for the activation of the Wnt/β-catenin pathway. However, neither the alteration of APC nor frequent CTNNB1 mutations were seen in our analyses. Therefore, other mechanisms might be responsible for the common activation of the Wnt/β-catenin pathway.

Andrographolide promotes vincristine-induced SK-NEP-1 tumor cell death via PI3K-AKT-p53 signaling pathway

Background

Nephroblastoma (Wilms’ tumor [WT]) is the most common malignant renal cancer in children. Although the outcome of WT has significantly improved as a result of the combination of surgery, chemotherapy, and radiotherapy; in some cases WT results in severe complications. Thus, novel strategies that would decrease treatment burden are required. The aim of the current study was to investigate the synergistic antitumor effect of andrographolide (AND) in combination with vincristine (VCR) on WT cells.

Methods

Cell Counting Kit-8 assay was used to investigate the synergistic antiproliferation effect of AND and/or VCR on SK-NEP-1 cells in vitro. Meanwhile, SK-NEP-1 xenografts were used to detect the antitumor effect in vivo. Apoptosis and autophagy were then detected by Annexin V, monodansylcadaverine staining. Finally, the underlying signaling transduction was determined with Western blotting.

Results

The combination of AND with VCR significantly suppressed SK-NEP-1 cell proliferation in vitro and inhibited xenograft tumor growth in vivo, compared with AND or VCR treatment alone. In addition, the synergistic antitumor effect of AND on the cells was due to an increased apoptosis, not autophagy. Moreover, PI3K-AKT-p53 signaling pathway was involved in the process of combination treatment, which was confirmed when a selective AKT activator was applied.

Conclusion

The combination of AND with VCR has a strong synergistic antitumor effect on WT via PI3K-AKT-p53 signaling pathway, thereby representing a potential treatment for WT in the near future.