Direct correlation of MR-DWI and histopathology of Wilms' tumours through a patient-specific 3D-printed cutting guide.

OBJECTIVES: The International Society of Paediatric Oncology-Renal Tumour Study Group (SIOP-RTSG) discourages invasive procedures to determine the histology of paediatric renal neoplasms at diagnosis. Therefore, the histological subtype of Wilms' tumours (WT) is unknown at the start of neoadjuvant chemotherapy. MR-DWI shows potential value as a non-invasive biomarker through apparent diffusion coefficients (ADCs). This study aimed to describe MR characteristics and ADC values of paediatric renal tumours to differentiate subtypes. MATERIALS AND METHODS: Children with a renal tumour undergoing surgery within the SIOP-RTSG 2016-UMBRELLA protocol were prospectively included between May 2021 and 2023. In the case of a total nephrectomy, a patient-specific cutting guide based on the neoadjuvant MR was 3D-printed, allowing a correlation between imaging and histopathology. Whole-tumour volumes and ADC values were statistically compared with the Mann-Whitney U-test. Direct correlation on the microscopic slide level was analysed through mixed model analysis. RESULTS: Fifty-nine lesions of 54 patients (58% male, median age 3.0 years (range 0-17.7 years)) were included. Forty-four lesions involved a WT. Stromal type WT showed the lowest median decrease in volume after neoadjuvant chemotherapy (48.1 cm3, range 561.5-(+)332.7 cm3, p = 0.035). On a microscopic slide level (n = 240 slides) after direct correlation through the cutting guide, stromal areas showed a significantly higher median ADC value compared to epithelial and blastemal foci (p < 0.001). With a cut-off value of 1.195 * 10-3 mm2/s, sensitivity, and specificity were 95.2% (95% confidence interval 87.6-98.4%) and 90.5% (95% confidence interval 68.2-98.3%), respectively. CONCLUSION: Correlation between histopathology and MR-DWI through a patient-specific 3D-printed cutting guide resulted in significant discrimination of stromal type WT from epithelial and blastemal subtypes. CLINICAL RELEVANCE STATEMENT: Stromal Wilms' tumours could be discriminated from epithelial- and blastemal lesions based on high apparent diffusion coefficient values and limited decrease in volume after neoadjuvant chemotherapy. This may aid in future decision-making, especially concerning discrimination between low- and high-risk neoplasms. KEY POINTS: MR-DWI shows potential value as a non-invasive biomarker in paediatric renal tumours. The patient-specific cutting guide leads to a correlation between apparent diffusion coefficient values and Wilms' tumour subtype. Stromal areas could be discriminated from epithelial and blastemal foci in Wilms' tumours based on apparent diffusion coefficient values.

Multimodality detection of tumour rupture in children with Wilms tumour.

BACKGROUND AND AIMS: Tumour rupture (TR) signifies stage III disease and requires treatment intensification, which includes radiotherapy. We studied the associations between radiological, surgical and pathology TR in children with Wilms tumour (WT) in a United Kingdom multicentre clinical study. PATIENTS AND METHODS: The IMPORT (Improving Population Outcomes for Renal Tumours of Childhood) study registered 712 patients between 2012 and 2021. Children with TR on central radiology review (CRR) at diagnosis and/or indication of preoperative TR on surgical forms were included. Correlation between radiology/surgery/pathology findings was made. RESULTS: Total 141 patients had TR identified (69 on CRR, 43 on surgical form and 29 on both), and 124/141 had images available for CRR, and 98/124 had features suggestive of TR on diagnostic CRR (63 magnetic resonance imaging/35 computed tomography). TR was limited to the renal fossa in 47/98 (48%) and intraperitoneal in 51/98 (52%). Three of 98(3%) had upfront surgery, and 87/95 (92%) had TR confirmed on post-chemotherapy preoperative scans. Among 80/98 (82%) cases with TR on CRR and available surgical forms, TR was not confirmed on surgery or pathology in 38/80, giving a false-positive rate of 48%. Preoperative TR was indicated on 72 surgical forms, with images available for CRR in 55. Twenty-six of 55 (47%) were false-negative for TR on CRR and of those 10/26 (38%) had TR confirmed on pathology. CONCLUSIONS: Radiology alone should not be used to define TR, as it does not accurately correlate with surgical or pathology findings, and therefore cannot be relied upon for definitive staging and treatment. A multidisciplinary team should take the decision regarding the final abdominal stage and treatment using a multimodality approach considering clinical, radiological, surgical and pathological findings.

Immune checkpoint markers and tumour mutation burden in Wilms tumour: a study of 59 cases.

Wilms tumour (WT) is the most common renal tumour in children, and studies of immune checkpoint inhibitors (ICIs) treatment and markers are limited in number. In this study we investigated the ICIs' related immune landscape by examining the expression of PD-L1, PD-1, CD8 and DNA mismatch repair (MMR) proteins by immunohistochemistry (IHC), tumour mutation burden (TMB), and correlations with histology and clinical outcome. Positive PD-L1 (SP263) expression was defined as modified combined positive score (CPS) ≥1. A total of 59 WTs (from 2000 to 2017), including eight (14.0%) with anaplasia, from 46 patients were analysed (45 primary and 14 metastatic). Thirteen WTs (13/59, 22%) were positive for PD-L1 (8 primary, 5 metastatic; CPS 1.11-3.42). Positive PD-L1 expression was associated with diffuse anaplasia (p<0.05) and significantly shorter progression-free survival (p<0.05) among WTs with favourable histology (n=39). CD8+ lymphocytes were present in all analysed WTs. A subset of CD8+ cells co-expressed PD-1, which was associated with favourable histology and treatment. MMR IHC stains identified two (2/18, 11%) WTs with isolated PMS2 loss. All six WTs analysed for TMB showed low mutation burden. We found CD8+ lymphocytes in all analysed WTs and identified a fraction of WT (17.8% of primary and 35.8% of metastatic) with positive PD-L1 CPS, suggesting potential response to ICIs in some patients.

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.

Bilateral Peters' anomaly, aniridia and Wilms tumour (WAGR syndrome) in monozygotic twins.

AIM: This study reports the bilateral association of Peters' anomaly and congenital aniridia in monozygotic twins subsequently diagnosed with Wilms tumour (WAGR syndrome). METHODS: Two monozygotic female twins were referred at age 2 months with bilateral corneal opacity. A diagnosis of Peters' anomaly associated to aniridia was made in both eyes of both twins. Physical examination and ultrasonography were carried out at 12 months of age to explore the possibility of WAGR-related anomalies, specifically Wilms tumour. DNA were isolated and subjected to whole exome sequencing. RESULTS: Peters' anomaly associated to aniridia in both eyes as well as bilateral Wilms tumour in both children were diagnosed. Exome analyses showed a large heterozygous deletion encompassing 6 648 473 bp in chromosome 11p13, using Integrative Genomics Viewer and AnnotSV software. CONCLUSION: WAGR syndrome is a rare contiguous gene deletion syndrome with a greater risk of developing Wilms tumour associated with Peters' anomaly and congenital aniridia. However, co-occurrence of both anomalies was rarely reported in twins, and never in both eyes of monozygotic twins. Here, we report the bilateral association of Peters' anomaly and congenital aniridia in monozygotic twins with WAGR syndrome.

How to improve initial diagnostic accuracy of kidney tumours in childhood?-A non-invasive approach.

Non-invasive differentiation of paediatric kidney tumours is particularly important in the SIOP-RTSG protocols, which recommend pre-operative chemotherapy without histological confirmation. The identification of clinical and tumour-related parameters may enhance diagnostic accuracy. Age, metastases, and tumour volume (TV) were retrospectively analysed in 3306 patients enrolled in SIOP/GPOH 9, 93-01, and 2001 including Wilms tumour (WT), congenital mesoblastic nephroma (CMN), clear cell sarcoma (CCSK), malignant rhabdoid tumour of the kidney (MRTK), and renal cell carcinoma (RCC). WT was diagnosed in 2927 (88.5%) patients followed by CMN 138 (4.2%), CCSK 126 (3.8%), MRTK 58 (1.8%) and RCC 57 (1.7%). CMN, the most common localized tumour (71.6%) in patients younger than 3 months of age, was diagnosed earliest and RCC the latest (median age [months]: 0 and 154, respectively) both associated with significantly smaller TV (median TV [mL]: 67.2 and 45.0, respectively). RCC occurred in >14% of patients older than 120 months or older than 84 months with TV <100 mL. Receiver operating characteristic analyses discriminated WT from CMN, RCC and MRTK regarding age (AUC = 0.976, 0.929 and 0.791) and TV (AUC = 0.768, 0.813 and 0.622). MRTK had the highest risk of metastasis (37.9%) despite young age, whereas the risk of metastasis increased significantly with age in WT. Age and TV at diagnosis can differentiate WT from CMN and RCC. MRTK must be considered for metastatic tumours at young age. Identification of CCSK without histology remains challenging. Combined with MRI-characteristics, including diffusion-weighted imaging, and radiomics and liquid biopsies in the future, our approach allows optimization of biopsy recommendations and prevention of misdiagnosis-based neoadjuvant treatment.

Multidimensional Transcriptomics Unveils RNF34 as a Prognostic Biomarker and Potential Indicator of Chemotherapy Sensitivity in Wilms' Tumour.

Nephroblastoma, colloquially known as Wilms' tumour (WT), is the predominant malignant renal neoplasm arising in the paediatric population. Modern therapeutic approaches for WT incorporate a synergistic combination of surgical intervention, radiotherapy, and chemotherapy, which substantially ameliorate the overall patient survival rate. Despite this, the optimal sequence of chemotherapy and surgical intervention remains a matter of contention, with each strategy presenting its own strengths and weaknesses that could influence clinical decision-making. To make some headway on this clinical dilemma, we deployed a multidimensional transcriptomics integration approach by analysing bulk RNA sequencing data with 136 samples, as well as single-nucleus RNA sequencing (snRNA-seq) and paired spatial transcriptome sequencing (stRNA) data from 32 WT specimens. Our findings identified a distinct elevation of RNF34 expression within WT samples, which correlated with unfavourable prognostic outcomes. Leveraging the Genomics of Drug Sensitivity in Cancer (GDSC), we simultaneously revealed that patients with high expression of RNF34 have higher sensitivity to commonly used chemotherapy drugs for WT. Furthermore, our analysis of snRNA and stRNA data unveiled a reduced proportion of RNF34 expression in neoplastic cells after chemotherapy. Moreover, stRNA data delineated a significant association between a higher proportion of RNF34 expression in cancer cells and adverse features such as anaplastic histology and tumour recurrence. Intriguingly, we also observed a close association between elevated RNF34 expression and a characteristic exhausted tumour immune microenvironment. Collectively, our findings underscore the pivotal role of RNF34 in the prognostic prediction potential and treatment sensitivity of WT. This comprehensive analysis can potentially inform and refine clinical decision-making for WT patients and guide future studies towards the development of optimized, rational therapeutic strategies.

Emergency Angioembolization for Life-Threatening Hemorrhage in Wilms Tumor.

Introduction: Renal artery embolization has been used in a palliative fashion for symptomatic relief of hematuria or flank pain in unresectable renal cell carcinoma in adults. There is limited data on the use of embolization for actively bleeding and unresectable tumors in the oncological pediatric population. Case Description: A previously healthy 5-year-old boy with no significant past medical or surgical history presented to the clinic with gradually worsening abdominal distension associated with occasional abdominal pain, gross hematuria, and lethargy for four months. Diagnostic investigations showed an 18-cm left-sided metastatic (pulmonary) renal tumor (Wilms), which was deemed unresectable on imaging. Treatment was planned according to the SIOP-RTSG protocol. However, he became hemodynamically and vitally unstable with acute, sudden distension of the abdomen on the left side after the first cycle of chemotherapy. Imaging showed active bleeding from an inferior branch of the left renal artery. Selective angioembolization was done, and chemotherapy was reinitiated with a patent left main renal artery. Following the fourth cycle of chemotherapy, he developed hemodynamic instability and abdominal pain; imaging revealed the resolution of pulmonary nodules and bleeding from the left renal artery (main); this was again embolized, and the patient was stabilized. The patient was operated on after optimization, and a complete resection of the mass was done with negative margins. On six months follow-up, he is well. Practical Implications: To the best of our knowledge, this is the first case where angioembolization has been done in conjunction with neoadjuvant chemotherapy to downsize a Wilms tumor to achieve favorable outcomes. Continued research efforts are necessary to optimize strategies and improve the prognosis for pediatric patients, and this case is one of the prime examples.

Prognostic and predictive biomarkers in paediatric solid tumours.

Characterisation of histological, immunohistochemical and molecular prognostic and predictive biomarkers has contributed significantly to precision medicine and better outcomes in the management of paediatric solid tumours. Prognostic biomarkers allow predictions to be made regarding a tumour's aggressiveness and clinical course, whereas predictive biomarkers help determine responses to a specific treatment. This review summarises prognostic biomarkers currently used in the more common paediatric solid tumours, with a brief commentary on the most relevant less common predictive biomarkers. MYCN amplification is the most important genetic alteration in neuroblastoma prognosis, and the histological classification devised by Shimada in 1999 is still used in routine diagnosis. Moreover, a new subgrouping of unfavourable histology neuroblastoma enables immunohistochemical characterisation of tumours with markedly different genetic features and prognosis. The predominant histology and commonly observed cytogenetic abnormalities are recognised outcome predictors in Wilms tumour. Evaluation for anaplasia, which is tightly associated with TP53 gene mutations and poor outcomes, is central in both the International Society of Paediatric Oncology and the Children's Oncology Group approaches to disease classification. Characterisation of distinct genotype-phenotype subclasses and critical mutations has expanded overall understanding of hepatoblastoma outcomes. The C1 subclass hepatoblastoma and CTNNB1 mutations are associated with good prognosis. In contrast, the C2 subclass, NFE2L2 mutations, TERT promoter mutations and high expression of oncofetal proteins and stem cell markers are associated with poor outcomes. Risk stratification in sarcomas is highly variable depending on the entity. The prognosis of rhabdomyosarcoma, for example, primarily depends on histological and molecular characteristics. Advances in our understanding of clinically significant biomarkers will translate into more precise diagnoses, improved risk stratification and more effective and less toxic treatment in this challenging group of patients.

Pulmonary metastatectomy in pediatric cancer patients at National Cancer Institute, Egypt: prognostic factors and outcome.

BACKGROUND: Metastatic tumors account for 80% of all lung tumors in children. Wilms tumour and osteosarcoma are the most tumors of childhood that produce lung metastases. The aim of the current study is to assess the prognostic factors of pulmonary metastatectomy in pediatric solid tumours as age, number, size, site,laterality, resectability of pulmonary nodules, and number of Thoracotomies. Calculate overall survival among patients who underwent pulmonary metastatectomy. METHODS: It is a retrospective study including all pediatric patients with metastatic solid tumors to lungs treated at pediatric oncology department, National Cancer Institute, Cairo University from 2008 to 2014. Fifty-five patients were included, 43 (78.2℅) patients of them had Osteosarcoma. RESULTS: Thirty (54.5℅)patients were male. The mean age was 15 years ranging from (4.5- 23) years. The site of primary disease was at lower limbs in 43 (78.2%) patients. All patients underwent complete surgical resection of the primary disease with negative margin, 22(51.1%) of the osteosarcoma patients did amputation with tumor necrosis less than 90%. All patients received chemotherapy and only 9 received radiation therapy. The patients were classified into four groups according to time of diagnosis of pulmonary metastasis: at time of diagnosis in 13 (21.8%) patients, within treatment in 16 (30.9%) patients, within first year follow up in 18 (32.7%) patients and detected late in 8 (14.5%) patients. Bilateral lung metastasis diagnosed by CT chest were detected in 42 (76.4%) patients. Size of metastatic nodules was ranging from (0.5 to 10 cm) with mean 3.4 cm. Number of metastatic nodules was ranging from (1 to 28) median 4.Metastatic complications were detected in 19 patients. 5-year OS was 74.8% in the study group, and 68% in osteosarcoma patients. Effect of prognostic factors as sex, time of respectability, laterality, tumor necrosis of the 1ry disease, Timing of lung metastasis, size and site of the primary, Surgical approach of metastatectomy, postoperative complications on overall survival of the studied patients was done with significant P-value of tumor necrosis of the 1ry disease and Timing of lung metastasis 0.017, 0.001 respectively. CONCLUSION: Resection of pulmonary metastases of pediatric solid tumours is a safe and effective treatment that offers better survival.

The rationale for nephron-sparing surgery in unilateral non-syndromic Wilms tumour.

The central question of nephron-sparing surgery in unilateral non-syndromic Wilms tumour sits at a crossroads between surgery, oncology, and nephrology. There has been a significant paradigm shift in paediatric oncology towards reducing toxicity and addressing long-term treatment-related sequalae amongst childhood cancer survivors. After paediatric nephrectomy and 30-50 years of follow-up, 40% of patients will have chronic kidney disease, including 22% with hypertension and 23% with albuminuria. It is difficult to predict which patients will progress to develop hypertension, reduced glomerular filtration rate, albuminuria, and a higher cardiovascular risk. For these reasons, nephron-sparing surgery when it is technically feasible must be considered. To decrease the incidence of positive surgical margins (viable tumour present at a resection margin), incomplete lymph node sampling, and complications, these procedures should be performed at specialist and experienced reference centres. Based on the impacts of individual treatment pathways, survivors of childhood WT need to be followed through adulthood for early detection of chronic kidney disease, hypertension, and prevention of cardiovascular events.

Teratoma-associated and so-called pure Wilms tumour of the ovary represent two separate tumour types with distinct molecular features.

AIMS: Ovarian Wilms tumour (WT)/nephroblastoma is an extremely rare neoplasm that has been reported to occur in pure form or as a component of a teratomatous neoplasm. We hypothesized that teratoma-associated and pure ovarian WT may represent different tumour types with diverging molecular backgrounds. To test this hypothesis, we comprehensively characterized a series of five tumours originally diagnosed as ovarian WT. METHODS AND RESULTS: The five cases comprised three teratoma-associated (two mature and one immature) and two pure WTs. Two of the teratoma-associated WTs consisted of small nodular arrangements of "glandular"/epithelial structures, while the third consisted of both an epithelial and a diffuse spindle cell/blastemal component. The pure WTs consisted of "glandular" structures, which were positive for sex cord markers (including inhibin and SF1) together with a rhabdomyosarcomatous component. The two pure WTs harboured DICER1 pathogenic variants (PVs), while the three associated with teratomas were DICER1 wildtype. Panel-based DNA sequencing of four of the cases did not identify PVs in the other genes investigated. Analysis of the HA19/IGF2 imprinting region showed retention of imprinting in the pure WTs but loss of heterozygosity with hypomethylation of the ICR1 region in two of three teratoma-associated WTs. Furthermore, copy number variation and clustering-based whole-genome DNA methylation analyses identified divergent molecular profiles for pure and teratoma-associated WTs. CONCLUSION: Based on the morphological features, immunophenotype, and molecular findings (DICER1 PVs, copy number, and DNA methylation profiles), we suggest that the two cases diagnosed as pure primary ovarian WT represent moderately to poorly differentiated Sertoli Leydig cell tumours (SLCTs), while the tumours arising in teratomas represent true WTs. It is possible that at least some prior cases reported as pure primary ovarian WT represent SLCTs.

Molecular mechanism of Wilms tumour 1-associated protein in diabetes-related dry eye disease by mediating m6A methylation modification of lncRNA NEAT1.

Background: Dry eye disease (DED) is often secondary to diabetes mellitus (DM).Purpose: This study is to explore the action of Wilms tumor 1-associated protein (WTAP) in DM-DED via lncRNA NEAT1 m6A methylation.Methods: DM-DED mouse models were treated with sh-WTAP/sh-NEAT1, followed by assessment of corneal epithelial damage/histopathological changes. HCE-2 cells were exposed to hyperosmotic conditions to establish in vitro DED models and treated with oe-NEAT1/sh-NEAT1/sh-WTAP/nigericin (an NLRP3 inflammasome inducer). Cell viability/apoptosis were evaluated by CCK-8/TUNEL. Levels of WTAP/NEAT1/inflammatory factors/NLRP3 inflammasome- and apoptosis-related markers were determined. m6A modification was examined by MeRIP-qPCR and NEAT1 stability was also detected.Results: DM-DED mice exhibited up-regulated WTAP/NEAT1 expression and severe corneal damage, whereas WTAP/NEAT1 knockdown alleviated inflammation/corneal damage. In hyperosmolarity-induced HCE-2 cells, NEAT1 aggravated inflammation and apoptosis, while NEAT1 knockdown suppressed NLRP3 inflammasome activation and ameliorated cell injury. Hyperosmolarity-induced WTAP expression increased m6A modification and NEAT1 mRNA stability. WTAP mediated m6A methylation of NEAT1 and NLRP3 inflammasome activation in DM-DED mice.

Localized pleural mesothelioma in a dog.

Malignant mesotheliomas with localized growth are extremely rare in dogs. A 9-year-old male dog presented with a localized tumour that originated from the parietal pleura and had polypoid growth in the thoracic cavity. Histological examination revealed that the tumour consisted of tubular formations with scattered cysts and minimal papillary growth pattern. Neoplastic cells were immunopositive for mesothelial markers (calretinin and Wilms' tumour gene 1) and negative for carcinoma markers (thyroid transcription factor 1 and tumour protein 63). The animal was alive with no recurrence or metastasis/dissemination 11 months after surgery. To the best of our knowledge, this is the first report of a localized mesothelioma in a dog without metastasis/dissemination and highlights the value of mesothelial markers for an accurate diagnosis.

Impact of the COVID-19 pandemic on paediatric renal tumour presentation and management, a SIOP renal tumour study group study.

BACKGROUND: The COVID-19 pandemic had global catastrophic effects on the management of non-communicable diseases including paediatric cancers. Restrictions during the start of 2020 complicated timely referrals of patients to specialized centres. We aimed to evaluate the pandemic's impact on the number of new diagnoses, disease characteristics and management delay for paediatric renal tumour patients included in the SIOP-RTSG-UMBRELLA study, as compared with data from a historical SIOP-RTSG trial (2005-2009). METHODS: The number of intensive care admissions, population mobility rates and national lockdown periods/restrictions were used as proxies of the pandemic's severity and impact on societies. Clinical and tumour data were extracted from the SIOP-RTSG-UMBRELLA study and from historical SIOP-RTSG trials. RESULTS: During the first lockdown in Europe, the number of newly diagnosed patients decreased following restrictions and population immobilisation. Additionally, there was a higher proportion of advanced disease (37% vs. 17% before and after COVID-9, p < 0.001) and larger median tumour volume (559 cm3 vs. 328 and 434 cm3 before and after, p < 0.0001). Also in Brazil, the proportion of advanced disease was higher during the national decrease in mobilisation and start of restrictions (50% and 24% vs. 11% and 18% before and after, p < 0.01). Tumour volume in Brazil was also higher during the first months of COVID-19 (599 cm3 vs. 459 and 514 cm3 ), although not significant (p = 0.17). We did not observe any delays in referral time nor in time to start treatment, even though COVID-19 restrictions may have caused children to reach care later. CONCLUSION: The COVID-19 pandemic briefly changed the tumour characteristics of children presenting with renal tumours. The longer-term impact on clinical outcomes will be kept under review.

PDGF-BB/PDGFRß induces tumour angiogenesis via enhancing PKM2 mediated by the PI3K/AKT pathway in Wilms' tumour.

Platelet-derived growth factor receptor-ß (PDGFRß) is a critical type III receptor tyrosine kinase family member, which is involved in Wilms' tumour (WT) metastasis and aerobic glycolysis. The role of PDGFRß in tumour angiogenesis has not been fully elucidated. Here, we examined the effect of PDGFRß on angiogenesis in WT. First, the NCBI database integrated three datasets, GSE2712, GSE11151, and GSE73209, to screen differentially expressed genes. The R language was used to analyse the correlation between PDGFRB and vascular endothelial growth factor (VEGF). The results showed that PDGFRB, encoding PDGFRß, was upregulated in WT, and its level was correlated with VEGFA expression. Next, PDGFRß expression was inhibited by small interfering RNA (siRNA) or activated with the exogenous ligand PDGF-BB. The expression and secretion of the angiogenesis elated factor VEGFA in WT G401 cells were detected using Western blotting and ELISA, respectively. The effects of conditioned medium from G401 cells on endothelial cell viability, migration, invasion, the total length of the tube, and the number of fulcrums were investigated. To further explore the mechanism of PDGFRß in the angiogenesis of WT, the expression of VEGFA was detected after blocking the phosphatidylinositol-3-kinase (PI3K) pathway and inhibiting the expression of PKM2, a key enzyme of glycolysis. The results indicated that PDGFRß regulated the process of tumour angiogenesis through the PI3K/AKT/PKM2 pathway. Therefore, this study provides a novel therapeutic strategy to target PDGFRß and PKM2 to inhibit glycolysis and anti-angiogenesis, thus, developing a new anti-vascular therapy.

Circulating microRNA profiles in Wilms tumour (WT): A systematic review and meta-analysis of diagnostic test accuracy.

Background: Wilms tumour (WT) is caused by aberrant embryonic kidney development and associated with dysregulated expression of short, non-protein-coding RNAs termed microRNAs (miRNAs). At present, there is no reliable circulating biomarker of WT, and this remains an urgent unmet clinical need. Such biomarkers may assist diagnosis, subtyping/prognostication, and disease-monitoring. Here, we established the list of dysregulated circulating miRNAs in WT from the existing published literature. Methods: Regardless of publication date, PubMed, Scopus, Web-of-Science, and Wiley online library databases were searched for English/French studies on WT circulating miRNAs. The PRISMA-compliant search was registered in PROSPERO. The QUADAS tool measured retained article quality. The meta-analysis assessed the sensitivity and specificity of miRNAs for WT diagnosis. Results: Qualitative analysis included 280 samples (172 WT patients; 108 healthy controls) from five of 450 published articles. The study uncovered 301 dysregulated miRNAs (144 up-regulated, 143 down-regulated, 14 conflicting). The pooled sensitivity, specificity, and AUC of the 49 significantly dysregulated microRNAs from two studies was 0.67 [0.62; 0.73], 0.95 [0.92; 0.96] and 0.77 [0.73; 0.81] respectively, indicating a stronger diagnostic potential for WT. Conclusions: Circulating miRNAs show promise for WT diagnosis and prognosis. More research is needed to confirm these findings and determine associations with tumour stage/subtype. Prospero registration number: CRD42022301597.

Testicular teratoma with nephroblastoma in an adult - case report and literature review.

Testicular germ cell tumours are the most common malignancies in young men. Germ cell tumours can be classified as seminomas or non-seminomas, each with different clinical features and treatment approaches. Germ cell tumours are occasionally associated with somatic-type malignancy, particularly in metastatic lymph nodes after adjuvant chemotherapy. Adenocarcinomas and rhabdomyosarcoma are the most common malignancies in this setting. In this report, we present a unique case of a 37-year-old patient who presented with a testicular teratoma containing a nephroblastoma component. The tumour exhibited characteristic morphology that resembled foetal kidney and expressed nuclear WT-1 and PAX-8 on immunohistochemistry. Following surgery, the patient opted for active surveillance and remains disease-free. To date, only 7 cases of nephroblastoma in primary testicular teratoma have been reported. This case highlights the importance of considering this rare entity in the differential diagnosis of testicular teratomas and the need for careful pathological examination.

Retinoic acid promotes differentiation of WiT49- but not of CCG99-11 Wilms tumour cells.

BACKGROUND: Most children with Wilms tumour are successfully treated with multidrug chemotherapy and surgery. These treatments cause severe side effects for the patients, an issue that needs to be addressed by exploring other treatment options with less or no side effects. One option is to complement current therapies with agents that could potentially induce tumour cell differentiation, for example retinoic acid (RA). AIMS: To facilitate quick assessment of an agent's effect on Wilms tumour differentiation by a rapid in vitro model system. METHODS AND RESULTS: Here WiT49 and CCG99-11 Wilms tumour cells were treated with 10 µM RA for 72 h or 9 days. Cultured cells were scraped off from Petri dishes, pelleted and embedded in paraffin in the same way as clinical tumour specimens are preserved. Cell morphology and differentiation were evaluated by analyses of haematoxylin eosin (H&E) and immunohistochemical stainings. Based on H&E, WT1 and CKAE1/3 stainings, RA treatment induced further epithelial differentiation of WiT49 cells, whereas there was no sign of induced maturation in CCG99-11 cells. Ki67 staining showed that RA inhibited cell proliferation in both cell lines. CONCLUSIONS: Our study shows that in vitro culturing of WiT49 and CCG99-11 cells, followed by pelleting and paraffin embedding of cell pellets, could aid in a quick evaluation of potential differentiating agents against Wilms tumour. In addition, our results strengthen previous results that retinoic acid could be a potential complement to regular Wilms tumour treatment.

Conventional fractionated radiotherapy outcomes for young dogs with nephroblastoma of the spinal cord: 5 cases.

Published radiotherapy results for spinal nephroblastomas in dogs are limited. In this retrospective longitudinal study (1/2007-1/2022), five dogs with a median age of 2.8 years received post-operative 3D conformal, conventional fractionated radiotherapy (CFRT) with 2-4 fields (parallel-opposed with or without two hinge-angle fields), for an incompletely resected nephroblastoma. Clinical findings prior to surgery included one or more of the following: pelvic limb paresis (5), faecal incontinence (2), flaccid tail (1), non-ambulatory (2) and deep pain loss (1). All masses were located between T11 and L3 and surgically removed via hemilaminectomy. Dogs received 45-50 Gray (Gy) in 18-20 fractions, and no dogs received chemotherapy post-radiation. At analysis, all dogs were deceased, with none lost to follow-up. The median overall survival (OS) from first treatment to death of any cause was 3.4 years (1234 days; 95% CI 68 days-upper limit not reached; range: 68-3607 days). The median planning target volume was 51.3 cc, with a median PTV dose of 51.4 Gy and median D98 = 48.3 Gy. Late complications or recurrence was difficult to fully determine in this small dataset; however, some degree of ataxia persisted throughout life in all dogs. This study provides preliminary evidence that post-operative radiotherapy may result in prolonged survival times dogs with spinal nephroblastomas.