Agreement between clinicoradiological signs at diagnosis and radiohistological analysis after neoadjuvant chemotherapy of suspected Wilms tumor rupture: Consequences on therapeutic choices

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.

[Renal tumors in children and adolescents]

CLINICAL/METHODOLOGICAL ISSUE

Diagnosis and therapy of renal tumors in children and adolescents are standardized by study protocols from major international societies. Imaging plays a central role, and in Europe patients between the ages of 6 months and 14 years with renal tumors are referred to neoadjuvant chemotherapy without histological confirmation according to the study protocol due to the frequency of Wilms tumor.

STANDARD RADIOLOGIC METHODS

Ultrasound is used worldwide as the primary investigative procedure for suspected renal tumors. In Europe, magnetic resonance imaging (MRI) has become established for more advanced diagnosis. In addition to differential diagnosis, staging is crucial for therapy. According to current protocol, this includes computed tomography (CT) of the thorax for the evaluation of pulmonary metastases.

METHODOLOGICAL INNOVATIONS

Diffusion-weighted MRI provides promising results for the differentiation of nephroblastoma subtypes in addition to improved detectability of tumor foci. However, sufficient evidence is lacking.

PERFORMANCE

Differentiation of Wilms tumor from the highly malignant non-Wilm tumors, such as malignant rhabdoid tumor and clear cell sarcoma of the kidney, remains inconclusive based on imaging alone. Differential diagnosis is, therefore, based on morphologic and epidemiologic criteria.

ASSESSMENT

The high degree of standardization in the diagnosis and treatment of renal tumors in children and adolescents has led to a significant improvement in prognosis. Overall survival of patients with Wilms tumor is currently over 90%.

Duplex kidney complicated with preoperative inferior nephroblastoma rupture in children: a case report and literature review

Background

We admitted a child with a duplex kidney combined with preoperative rupture of nephroblastoma and used this case to discuss the clinical features and treatment of this disease.

Case presentation

We retrospectively analyzed the clinical data of a 5-year-old girl with preoperative duplex kidney rupture combined with inferior nephroblastoma who was admitted to the Fourth Hospital of Baotou. In addition, we reviewed the relevant literature. The patient’s details were as follows: weight, 17 kg; height, 108 cm; and body surface area, 0.7 m². Abdominal ultrasound for abdominal pain revealed the presence of a left-sided renal mass; enhanced abdominal computed tomography further confirmed it to be a left-sided duplex kidney measuring approximately 6 × 5 × 5 cm, with a rupture originating from the lower kidney. The PubMed database was searched from 2010 to 2020 for the terms “Wilms’ tumor” and “Duplex” and “Wilms’ tumor” and “Rupture.” The treatment plan was preoperative chemotherapy (vincristine/dactinomycin, VA regimen) + left kidney tumor radical surgery + postoperative chemotherapy (actinomycin-D/VCR/doxorubicin, AVD regimen). Postoperative pathology revealed an International Society of Pediatric Oncology intermediate-risk stage-3 nephroblastoma (mixed type) in the left kidney. Literature review was performed with 71 cases meeting the set criteria with an aim to analyze and summarize the clinical characteristics and treatment of patients with ruptured nephroblastoma and duplex kidney combined with nephroblastoma.

Conclusions

To our knowledge, no previous studies have reported preoperative duplex kidney combined with nephroblastoma rupture. In patients with this condition, preoperative chemotherapy is recommended when the vital signs are stable and tumor resection can be performed after the tumor has shrunk to prevent secondary spread. If the patient’s vital signs are unstable, emergency exploratory surgery is needed. If the nephroblastoma rupture is old and limited, surgery can be performed when the tumor size is small.

Preoperative Wilms tumor rupture in children

PURPOSE

According to the guidelines of International Society of Pediatric Oncology (SIOP) and National Wilms Tumor Study (NWTS), Wilms tumor with preoperative rupture should be classified as at least stage III. Few clinical reports can be found about preoperative Wilms tumor rupture. The purpose of this study was to investigate our experience on the diagnosis, treatment and prognosis of preoperative Wilms tumor rupture.

METHODS

Patients with Wilms tumor who underwent treatment according to the NWTS or SIOP protocol from January 2008 to September 2017 in Beijing Children's Hospital were reviewed retrospectively. The clinical signs of preoperative tumor rupture were acute abdominal pain, and/or fall of hemoglobin. The radiologic signs of preoperative tumor rupture are as follows: (1) retroperitoneal and/or intraperitoneal effusion; (2) acute hemorrhage located in the sub-capsular and/or perirenal space; (3) tumor fracture communicating with peritoneal effusion; (4) bloody ascites. Patients with clinical and radiologic signs of preoperative tumor rupture were selected. Patients having radiologic signs without clinical symptoms were also selected. The clinical data, treatments and outcomes were analyzed. Meanwhile, patients without preoperative Wilms tumor rupture during the same period were collected and analyzed.

RESULTS

565 Patients with Wilms tumor were registered in our hospital. Of these patients, 45 patients were diagnosed with preoperative ruptured Wilms tumor. All preoperative rupture were confirmed at surgery. Spontaneous tumor rupture occurred in 41 patients, the other 4 patients had traumatic history. Of the 45 patients, 41 were classified as stage III, 3 patients with pulmonary metastases were classified as stage IV, and one patient with bilateral tumors were classified as stage V. Of these patients with preoperative tumor rupture at stage III, 30 patients had clinical and radiologic signs of tumor rupture, the other 11 patients had radiologic signs without clinical symptoms. Among the 41 patients at stage III, 13 patients had immediate surgery without preoperative chemotherapy (immediate group), and 28 patients had delayed surgery after preoperative chemotherapy (delayed group). In immediate group, 12 patients had localized rupture, 1 patient underwent emergency surgery because of continuous bleeding. In delayed group, 4 had inferior vena cava tumor embolus (1 thrombus extended to inferior vena cava behind the liver, three thrombi got to the right atrium), 4 crossed the midline with large tumors, 20 had extensive rupture without localization. In immediate group, tumor recurrence and metastasis developed in 2 patients, and no death occurred. In the delayed group, tumor recurrence and metastasis developed in 8 patients, and 7 patients died. During the same period, 41 patients were classified as stage III without preoperative rupture. In the non-ruptured group, tumor recurrence and metastasis developed in 3 patients, and 4 patients died. The median survival time in the ruptured group (both immediate group and delayed group) and non-ruptured group were (85.1 ± 7.5) and (110.3 ± 5.6) months, and the 3-year cumulative survival rates were 75.1% and 89.6%, respectively. The overall survival rate between the ruptured and non-ruptured groups showed no statistic difference (P = 0.256). However, there was significant difference in recurrence or metastasis rate between the ruptured and non-ruptured groups (24.4% vs 7.3%; P = 0.031).

CONCLUSION

Contrast-enhanced computed tomography (CT) and ultrasonography (US) are of major value in the diagnosis of preoperative tumor rupture, and immediate surgery or delayed surgery are available therapeutic methods. The treatment plan was based on patients' general conditions, tumor size, position and impairment degree of tumor rupture, extent of invasion and experience of a multidisciplinary team (including surgeon and anesthesiologists). In our experience, for ruptured preoperative tumor diagnosed with stage III, the criteria for immediate surgery are as follows: tumor not acrossing the midline, tumor without inferior vena cava thrombus, localized rupture, being capable of complete resection. Selection criteria for delayed surgery after preoperative chemotherapy are as follows: large tumors, long inferior vena cava tumor thrombus, tumors infiltrating to surrounding organs, unlocalized rupture, tumors can not being resected completely. Additionally, patients with preoperative Wilms tumor rupture had an increased risk of postoperative recurrence or metastasis.

RNA-Sequencing, Connectivity Mapping, and Molecular Docking to Investigate Ligand-Protein Binding for Potential Drug Candidates for the Treatment of Wilms Tumor

Background

Wilms tumor, or nephroblastoma, is a malignant pediatric embryonal renal tumor that has a poor prognosis. This study aimed to use bioinformatics data, RNA-sequencing, connectivity mapping, molecular docking, and ligand-protein binding to identify potential targets for drug therapy in Wilms tumor.

Material/Methods

Wilms tumor and non-tumor samples were obtained from high throughput gene expression databases, and differentially expressed genes (DEGs) were analyzed using the voom method in the limma package. The overlapping DEGs were obtained from the intersecting drug target genes using the Connectivity Map (CMap) database, and systemsDock was used for molecular docking. Gene databases were searched for gene expression profiles for complementary analysis, analysis of clinical significance, and prognosis analysis to refine the study.

Results

From 177 cases of Wilms tumor, there were 648 upregulated genes and 342 down-regulated genes. Gene Ontology (GO) enrichment analysis showed that the identified DEGs that affected the cell cycle. After obtaining 21 candidate drugs, there were seven overlapping genes with 75 drug target genes and DEGs. Molecular docking results showed that relatively high scores were obtained when retinoic acid and the cyclin-dependent kinase inhibitor, alsterpaullone, were docked to the overlapping genes. There were significant standardized mean differences for three overlapping genes, CDK2, MAP4K4, and CRABP2. However, four upregulated overlapping genes, CDK2, MAP4K4, CRABP2, and SIRT1 had no prognostic significance.

Conclusions

RNA-sequencing, connectivity mapping, and molecular docking to investigate ligand-protein binding identified retinoic acid and alsterpaullone as potential drug candidates for the treatment of Wilms tumor.

The role of imaging in the initial investigation of paediatric renal tumours

Imaging has a key role in the assessment of paediatric renal tumours, especially when the initial treatment approach is to proceed to standard chemotherapy without histological confirmation. In Europe, according to the International Society of Paediatric Oncology guidelines, core needle biopsy is not routinely done unless the child is older than 10 years. Between age 6 months and 9 years, the child is treated with a standard regimen of preoperative chemotherapy unless there are concerns about non-Wilms' tumour pathology. Atypical imaging findings could therefore stratify a child into a different treatment protocol, and can prompt the need for pretreatment histology. This review details the latest protocols and techniques used in the assessment of paediatric renal tumours. Important imaging findings are discussed, especially the features that might prompt the need for a pretreatment biopsy. Local radiology practices vary, but both MRI and CT are widely used as routine imaging tests for the assessment of paediatric renal tumours in Europe. Advances in imaging technology and MRI sequences are facilitating the development of new techniques, which might increase the utility of imaging in terms of predicting tumour histology and clinical behaviour. Several of these new imaging techniques are outlined here.