Innovations in the management of Wilms' tumor

Inter-Ethnic Variations in the Clinical, Pathological, and Molecular Characteristics of Wilms Tumor

Wilms tumor is the commonest primary renal malignancy in children and demonstrates substantial inter-ethnic variation in clinical, pathological, and molecular characteristics. Wilms tumor occurs at a lower incidence and at a younger age in Asians compared to Caucasians and Africans. Asians also present at an earlier stage of disease, with a higher incidence of favorable histology tumors and a lower incidence of perilobar nephrogenic rests compared to Caucasians, while African children present with more advanced disease. Studies have implicated population differences in the incidence of WT1 mutations, loss of imprinting of the IGF2 locus, and loss of heterozygosity of 1p/16q, or 1q gain as possible bases for epidemiological differences in the disease profile of Wilms tumors in various ethnic groups. Yet, evidence to support these associations is confounded by differences in treatment protocols and inequalities in the availability of treatment resources and remains limited by the quality of population-based data, especially in resource-limited settings.

Factors Associated with Outcomes at 1 Year in Paediatric Post-nephrectomy Patients for Nephroblastoma at the University Teaching Hospital and Cancer Diseases Hospital in Lusaka, Zambia

BACKGROUND

Nephroblastoma is the most common primary malignant renal tumour of childhood. The survival rates in high-income countries are approximately 90%. However, low-income countries have low survival rates of 20%-50%. This study assessed factors associated with treatment outcomes of children post-nephrectomy for nephroblastoma at the University Teaching Hospital and Cancer Diseases Hospital in Lusaka, Zambia.

MATERIALS AND METHODS

A retrospective observational cohort study was conducted, where all children diagnosed with unilateral Wilms tumour below the age of 16 years who had nephrectomy from July 2016 to June 2019 were enrolled. Sociodemographic, clinical characteristics and treatment outcomes were noted. All data were coded and stored in a tabular format using Microsoft Excel. Statistical software STATA version 13 was used for analysis.

RESULTS

Thirty patients were enrolled. The male-to-female ratio was 1:1. The 1-year event-free survival was 46.7%. Treatment abandonment accounted for 36.6% of the participants. 16.7% of the patients had disease progression. No patient had a relapse or died during the 1-year follow-up period. 66.7% had advanced disease stages III and IV. Advancement in age (above 4.3 years), living in a rural environment more than 100 km away from Lusaka and advanced disease stage were all associated with a poor outcome.

CONCLUSIONS

Factors associated with a poor outcome in this study were advanced age and late presentation.

Wilms tumor in horseshoe kidney with extensive vascular thrombosis: A case report

INTRODUCTION AND IMPORTANCE

Wilms tumor (WT), a prevalent pediatric renal malignancy (7 %), frequently intertwines with genitourinary anomalies. This unique report presents a case of WT combined with horseshoe Kidney and an extending atrial thrombus, emphasizing critical management considerations.

CASE PRESENTATION

A 3-year-old boy, experiencing flank pain and weight loss, manifested a WT linked to horseshoe Kidney, accompanied by an atrial thrombus. Neoadjuvant chemotherapy downsized the tumor and thrombus, enabling successful surgical intervention. Post-surgery, 27 weeks of adjuvant chemotherapy were administered. Over three years, follow-up exhibited renal recovery, no recurrence, and clear CT scans.

DISCUSSION

Prompt identification, precise imaging (via CT angiography), and multidisciplinary care are pivotal for managing WT in horseshoe Kidney cases. Preoperative chemotherapy notably reduced tumor and thrombus sizes, enhancing surgical feasibility. Long-term vigilance is essential for recurrence and treatment-related complications.

CONCLUSION

Effectively managing WT in horseshoe Kidneys demands timely recognition, meticulous imaging, and collaborative management. Successful outcomes highlight preoperative chemotherapy's benefits and underscore extended monitoring's significance in confirming sustained recovery.

One year overall survival of wilms tumor cases and its predictors, among children diagnosed at a teaching hospital in South Western Uganda: a retrospective cohort study

BACKGROUND

Wilms tumor (WT) is the second most common solid tumor in Africa with both low overall survival (OS) and event-free survival (EFS) rates. However, no known factors are predicting this poor overall survival.

OBJECTIVE

The study was to determine the one-year overall survival of WT cases and its predictors among children diagnosed in the pediatric oncology and surgical units of Mbarara regional referral hospital (MRRH), western Uganda.

METHODOLOGY

Children's treatment charts and files diagnosed and managed for WT were retrospectively followed up for the period between January 2017 to January 2021. Charts of children with histologically confirmed diagnoses were reviewed for demographics, clinical and histological characteristics, as well as treatment modalities.

RESULTS

One-year overall survival was found to be 59.3% (95% CI: 40.7-73.3), with tumor size greater than 15 cm (p 0.021) and unfavorable WT type (p 0.012) being the predominant predictors.

CONCLUSION

Overall survival (OS) of WT at MRRH was found to be 59.3%, and predictive factors noted were unfavorable histology and tumor size greater than 115 cm.

Prediction of Wilms' Tumor Susceptibility to Preoperative Chemotherapy Using a Novel Computer-Aided Prediction System

Wilms' tumor, the most prevalent renal tumor in children, is known for its aggressive prognosis and recurrence. Treatment of Wilms' tumor is multimodal, including surgery, chemotherapy, and occasionally, radiation therapy. Preoperative chemotherapy is used routinely in European studies and in select indications in North American trials. The objective of this study was to build a novel computer-aided prediction system for preoperative chemotherapy response in Wilms' tumors. A total of 63 patients (age range: 6 months-14 years) were included in this study, after receiving their guardians' informed consent. We incorporated contrast-enhanced computed tomography imaging to extract the texture, shape, and functionality-based features from Wilms' tumors before chemotherapy. The proposed system consists of six steps: (i) delineate the tumors' images across the three contrast phases; (ii) characterize the texture of the tumors using first- and second-order textural features; (iii) extract the shape features by applying a parametric spherical harmonics model, sphericity, and elongation; (iv) capture the intensity changes across the contrast phases to describe the tumors' functionality; (v) apply features fusion based on the extracted features; and (vi) determine the final prediction as responsive or non-responsive via a tuned support vector machine classifier. The system achieved an overall accuracy of 95.24%, with 95.65% sensitivity and 94.12% specificity. Using the support vector machine along with the integrated features led to superior results compared with other classification models. This study integrates novel imaging markers with a machine learning classification model to make early predictions about how a Wilms' tumor will respond to preoperative chemotherapy. This can lead to personalized management plans for Wilms' tumors.

Nephron-sparing surgery in nonsyndromic unilateral wilms' tumor: An insight into the ongoing surgical controversy

Background:

Unilateral Wilms' tumor (uWT) is the most common renal malignancy in the pediatric population. Although the onset of surgical intervention like radical nephrectomy (RN) has substantially reduced the mortality rate, recent evidence has raised concerns regarding several postoperative complications associated with this procedure. Nephron-sparing surgery (NSS) has been reported to avoid such postoperative complications and have high technical success rate. However, not much literature is available comparing the efficacy of RN and NSS for managing nonsyndromic uWT, which makes it less acceptable globally.

Materials and Methods and Results:

A systematic identification of the literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines on four academic databases: MEDLINE, Scopus, EMBASE, and CENTRAL. Out of 1017 records, 20 manuscripts including 312 patients were included in the review; 4 patients treated by the author (unpublished data) have also been included. The studies included 7 retrospective case series with no comparison group, 4 retrospective case series with comparison group, 4 retrospective series with a cursory mention of NSS in uWT, 2 case reports, 1 protocolized prospective trial with comparison group, 1 administrative database analysis with comparison group, and 1 randomized controlled study. In all, 316 patients with nonsyndromic uWT were studied. The pretherapy volumes of the WT ranged from 2.4 to 640 ml. Majority of them were administered preoperative chemotherapy. About half of the patients (n = 159) (50.3%) were Stage I tumors. Stage II, III, and IV tumors were seen in 23 (7.3%), 20 (6.3%), and 3 (1%) patients. Stage was not specified in 111 (35.1%) patients. Majority of them were “intermediate risk” WT. All these tumors were nonanaplastic. Surgical margins were reported positive in 13 (4%) patients. Overall and event-free survivals were 100% in most of the studies; only handful of relapses were noted in this systematic review.

Conclusions:

This qualitative systematic review recommends the use of NSS for nonsyndromic uWT. The procedure accounts for higher postoperative renal function and lesser incidence of hypertension as compared to the radical nephrectomy. Overall and event-free survivals are comparable or even better with NSS.

Recombinant Chinese Hu191 measles virus exhibits a significant antitumor activity against nephroblastoma mediated by immunogenic form of apoptosis

In previous studies oncolytic measles viruses (MVs) have shown significant antitumor activity against various tumors. In our research recombinant MV-Hu191 (rMV-Hu191), established via reverse genetics technology and expressing enhanced green fluorescent protein (EGFP), was evaluated for its therapeutic effects and related mechanisms against nephroblastoma cell lines. We built three different constructs based on rMV-Hu191 to express EGFP effectively. Our experiments showed that rMV-Hu191 expressing EGFP could efficiently infect and replicate in nephroblastoma cell lines. Caspase-induced apoptosis exerted a significant impact on MV-induced cell death, which was accompanied by emission of cellular ATP and high-mobility group protein 1 (HMGB1) and by translocation of calreticulin (CRT). Intratumoral injection of rMV-Hu191-EGFP resulted in significant regression of tumors in a G401 xenograft model. Our results indicate that the MV-Hu191 strain, which is widely used in China, is an appropriate vector for expression of foreign genes and could serve as a potentially good candidate for nephroblastoma therapy mediated by induction of apoptosis-associated immunogenic cell death (ICD).

Lithocholic bile acid induces apoptosis in human nephroblastoma cells: a non-selective treatment option

Lithocholic bile acid (LCA) has been reported to selectively kill cancer cells within many tumor cell lines including neuroblastoma or glioblastoma. Wilms’ tumor shares similarities with neuro- and glioblastoma. Hence, the aim of the study was to evaluate the effects of LCA on nephroblastoma. To test the effects of LCA, nephroblastoma cell line WT CLS1 was used. SK NEP1 was tested as well. It was originally classified as a nephroblastoma cell line but was meanwhile reclassified as an ewing sarcoma cell line. As control cell lines HEK 293 from embryonic kidney and RC 124 from adult kidney tissue as well as podocytes were used. The effects were evaluated using proliferation assay, caspase activity assay, FACS and Western blot. LCA showed a dose and time-dependent selective effect inducing apoptosis in nephroblastoma cells. However, these effects were not limited to the nephroblastoma cell line but also affected control kidney cell lines and the sarcoma cells; only podocytes are significantly less affected by LCA (at dosages < 200 µm). There were no significant differences regarding the TGR5 receptor expression. The study showed that LCA has a strong, yet unselective effect on all used in vitro cell-lines, sparing the highly differentiated podocytes in lower concentrations. Further studies are needed to verify our results before dismissing LCA as an anti-cancer drug.

Renal Nephroblastoma in a 17-Month-Old Jack Russell Terrier

A 17 mo old female Jack Russell terrier was diagnosed with unilateral primary malignant nephroblastoma. The dog presented with polyuria and polydipsia. Laboratory tests revealed polycythemia and elevated serum erythropoietin levels. Diagnostic imaging (i.e., MRI) revealed a unilateral renal mass without spinal cord involvement. Nephrectomy was performed, and the histopathologic diagnosis was nephroblastoma. The dog did not receive any chemotherapy, and there was no evidence of recurrent disease or metastasis over 30 mo after nephrectomy. This is the first case report of a dog presenting with polyuria and polydipsia found to be a result of nephroblastoma. Furthermore, this is the longest survival reported for canine nephroblastoma treated with nephrectomy alone.

[Expression of the Fra-1 gene in the peripheral blood of children with Wilms tumor]

OBJECTIVE

To study the expression of the Fra-1 gene in the peripheral blood of children with Wilms tumor and its clinical significance.

METHODS

Fifty children pathologically diagnosed with Wilms tumor between December 2012 and January 2018 were enrolled as the case group, and 40 healthy children for physical examination were selected as the control group. Among the 45 children with Wilms tumor who were followed up, the children with continuous remission were included in the ideal efficacy group (n=33), and those with recurrence, metastasis or death were included in the poor efficacy group (n=12). Peripheral blood samples were collected from all subjects. Quantitative real-time PCR was used to measure the mRNA expression of Fra-1.

RESULTS

The case group had significantly higher mRNA expression of Fra-1 in peripheral blood than the control group (P<0.05). In the case group, Fra-1 mRNA expression was significantly different between the individuals with and without distant metastasis and those with different TNM stages (P<0.05), but was not significantly different between the individuals with different sexes, ages, tumor diabetes, tumor locations and alpha-fetoprotein levels (P>0.05). The mRNA expression of Fra-1 was significantly lower in the ideal efficacy group than in the poor efficacy group (P<0.05).

CONCLUSIONS

Fra-1 may be involved in the development of Wilms tumor and plays a certain role in its development, invasion and metastasis, but the mechanism remains to be further studied.

Recent advances in the management of Wilms' tumor

The objective of this article is to present an overview of recent trends in the management of Wilms’ tumor. With improved survival rates in the past few decades, critical long-term adverse therapy effects (such as renal insufficiency, secondary malignancies, and heart failure) and prevention measures (i.e. nephron-sparing surgery and minimizing the use of radiotherapy) have gained worldwide attention. Specific disease biomarkers that could help stratify high-risk from low-risk patients, and therefore fine-tune management, are in great demand. Ultimately, we aim to enhance clinical outcomes and maintain or improve current survival rates while avoiding undesirable treatment side effects and minimizing the exposure and intensity of chemotherapy and radiotherapy.

Wilms Tumor Treatment Outcomes: Perspectives From a Low-Income Setting

Purpose

Wilms tumor is the commonest renal malignancy in childhood. Survival in high-income countries is approximately 90%, whereas in low-income countries, it is less than 50%. This study assessed treatment outcomes of patients with Wilms tumor at a Kenyan academic hospital.

Patients and Methods

We conducted a retrospective medical record review of all children diagnosed with Wilms tumor between 2010 and 2012. Data on treatment outcomes and various sociodemographic and clinical characteristics were collected.

Results

Of the 39 patients with Wilms tumor, 41% had event-free survival, 31% abandoned treatment, 23% died, and 5% had progressive or relapsed disease. Most patients presented at an advanced stage: stage I (0%), II (7%), III (43%), IV (40%), or V (10%). The most likely treatment outcome in patients with low-stage (I to III) disease was event-free survival (67%), whereas in those with high-stage (IV to V) disease, it was death (40%). No deaths or instances of progressive or relapsed disease were recorded among patients with low-stage disease; their only reason for treatment failure was abandonment of treatment. Stage of disease significantly affected treatment outcomes (P = .014) and event-free survival estimates (P < .001). Age at diagnosis, sex, duration of symptoms, distance to hospital, and health insurance status did not statistically significantly influence treatment outcomes or event-free survival estimates.

Conclusion

Survival of patients with Wilms tumor in Kenya is lower compared with that in high-income countries. Treatment abandonment is the most common cause of treatment failure. Stage of disease at diagnosis statistically significantly affects treatment outcomes and survival.

The roles of microRNAs in Wilms' tumors

Wilms' tumor is the most common renal tumor in children in which diffusely anaplastic or unfavorable histology foreshadows poor prognosis. MicroRNAs are small, non-coding RNAs that negatively regulate gene expression at the posttranscriptional level. Accumulating evidence shows that microRNA dysregulation takes part in the pathogenesis of many renal diseases, such as chronic kidney diseases, polycystic kidney disease, renal fibrosis, and renal cancers. In Wilms' tumor, dysregulation of some key oncogenic or tumor-suppressing microRNAs, such as miR-17~92 cluster, miR-185, miR-204, and miR-483, has been documented. In this review, we will summarize current evidence on the role of dysregulated microRNAs in the development of Wilms' tumor.

Primary mesenchymal chondrosarcoma with bilateral kidney invasion and calcification in renal pelvis: A case report and review of the literature

Mesenchymal chondrosarcoma (MC) is a rare malignant cartilaginous forming tumor. MC of the kidney is extremely rare, with only seven cases reported in the literature. The present study described the case of a 17-year-old male, who presented with sudden severe pain in the right flank and a high fever. Imaging studies demonstrated a large soft heterogeneous mass (7.8×9.5×15 cm) located between the liver and right kidney with no clear demarcation, and a well-demarcated mass (1.3×2.4 cm) with patchy dense calcification occupying the left renal pelvis. Following the diagnosis of a Wilms' tumor, the patient underwent a right radical nephrectomy and the pathological diagnosis was MC of the kidney. To the best of our knowledge, the current study presents the first case of MC with bilateral kidney invasion and calcification in the renal pelvis. In addition, the clinical, radiological and pathological features, and the management of this unusual neoplasm were discussed.

Second malignant neoplasms among children, adolescents and young adults with Wilms tumor

BACKGROUND

The goal of this study was to describe the incidence, characteristics, and outcomes of secondary malignant neoplasms (SMN) in survivors of Wilms tumor.

PROCEDURES

Patients who were 0-20 years of age at time of primary diagnosis with Wilms tumor and reported to the Surveillance, Epidemiology, and End Results [SEER] program between 1973 and 2011 were eligible for inclusion in the cohort. We used competing risks methods to estimate the cumulative incidence of SMNs and assess contributing factors for developing SMN. We estimated standardized incidence ratios (SIR), absolute excess risk and overall survival after SMN using standard methods.

RESULTS

Within the SEER database, 2,851 patients were diagnosed with Wilms tumor as their first malignancy. Of these, 34 patients were reported to have a SMN. Cumulative incidence of for a secondary malignancy was 0.6% (95% confidence interval [95% CI] 0.3-1.0%) at 10 years, 1.6% (95% CI 1.0-2.3%) at 20 years, and 3.8% (95% CI 2.4-5.9%) at 30 years. Median time from primary diagnosis to SMN diagnosis was 12.5 years. SIR for SMN for survivors of Wilms tumor was 3.4 (95% CI 2.2-4.9) with an absolute excess risk of 7.6 per 10,000 persons per year. Exposure to radiation did not significantly increase risk for development of second malignancy. Overall survival for patients with SMN was 64.5% at 5 years.

CONCLUSION

Survivors of Wilms tumor are at an increased risk of SMN compared to the general population, but the added risk is relatively small compared to other pediatric cancers.

HIF-1α contributes to proliferation and invasiveness of neuroblastoma cells via SHH signaling

The aim of this study was to investigate the effects of hypoxia-inducible factor-1α (HIF-1α) on the proliferation, migration and invasion of neuroblastoma (NB) cells and the mechanisms involved. We here initially used the real-time polymerase chain reaction (real-time PCR), Western blotting and immunohistochemistry (IHC) to detect the expression of HIF-1α and components of the sonic hedgehog (SHH) signaling pathway in NB cells and human specimens. Subsequently, cell proliferation, migration and invasion were analyzed using the cell counting assay, wound healing assay and Transwell system in two types of human NB cell lines, SH-SY5Y and IMR32. In addition, the role of HIF-1α in NB cells growth was determined in a xenograft nude mouse model. We found that the level of HIF-1α was significantly upregulated during NB progression and was associated with the expression of two components of SHH signaling, SHH and GLI1. We next indicated that the proliferation, migration and invasiveness of SH-SY5Y and IMR32 cells were significantly inhibited by HIF-1α knockdown, which was mediated by small interfering RNAs (siRNAs) targeting against its mRNA. Furthermore, the growth of NB cells in vivo was also suppressed by HIF-1α inhibition. Finally, the pro-migration and proliferative effects of HIF-1α could be reversed by disrupting SHH signaling. In conclusion, our results demonstrated that upregulation of HIF-1α in NB promotes proliferation, migration and invasiveness via SHH signaling.

Value of 18F-FDG PET and PET/CT for evaluation of pediatric malignancies

Successful management of solid tumors in children requires imaging tests for accurate disease detection, characterization, and treatment monitoring. Technologic developments aim toward the creation of integrated imaging approaches that provide a comprehensive diagnosis with a single visit. These integrated diagnostic tests not only are convenient for young patients but also save direct and indirect health-care costs by streamlining procedures, minimizing hospitalizations, and minimizing lost school or work time for children and their parents. (18)F-FDG PET/CT is a highly sensitive and specific imaging modality for whole-body evaluation of pediatric malignancies. However, recent concerns about ionizing radiation exposure have led to a search for alternative imaging methods, such as whole-body MR imaging and PET/MR. As we develop new approaches for tumor staging, it is important to understand current benchmarks. This review article will synthesize the current literature on (18)F-FDG PET/CT for tumor staging in children, summarizing questions that have been solved and providing an outlook on unsolved avenues.