Pediatric Abdominal Tumors Research Articles

Impact of cyclophosphamide on the morphological and histological changes in polyglycolic acid spacers.

In radiotherapy for pediatric abdominal tumors, determining the effect of concurrent chemotherapy on polyglycolic acid (PGA) spacers is crucial; yet this effect has not been validated. Therefore, we aimed to evaluate the impact of cyclophosphamide (CPA) chemotherapy on the PGA spacer using a rat model. Twenty-four rats were implanted with the spacer, and morphological changes in the spacer were assessed on CT for both the CPA-dosed group (40mg/kg) and the control group. The size and volume of the spacer were quantified using CT, while the degree of adhesion and microscopic examination of the tissue were determined using pathology specimens. Morphologically, the size of the spacer decreased over time in both the CPA-dosed and control groups, with no significant differences observed between groups. No significant differences in adhesion were observed between the two groups. Macrophages were observed around the PGA fibers, suggesting their involvement in the degradation of the PGA spacer. These results suggest that CPA does not cause significant clinically problematic degradation or adverse tissue reactions to the PGA spacer. This study reinforced the benefits of PGA spacers; however, future research focusing on in vivo longitudinal monitoring of individual rats, as well as on humans, is required.

Health-Related Quality of Life and Mental Health of Parents of Children with Pediatric Abdominal Tumors.

Abdominal tumors rarely occur in childhood but are associated with great psychological stress for patients and their families. Parents playing a central role in their children's treatment may experience adverse effects on their Health-Related Quality of Life (HRQoL) and mental health due to the children's illness and required treatment. Given the limited knowledge of the psychosocial burden of parents with children suffering from solid abdominal tumors, this study aims to assess their HRQoL and mental health along with the impact of various psychosocial factors. A cross-sectional cohort study was carried out involving 54 parents of children with solid abdominal tumors who had surgery at the University Medical Center Hamburg-Eppendorf in Germany. The results were compared with 46 parents of children undergoing routine surgeries without a prior tumor diagnosis, and with normative values. Data were obtained using standardized questionnaires. Parents of the index group showed significantly worse HRQoL and limited mental health. Furthermore, they showed significantly higher parental burden in several subscales and less social support in comparison with the control group. Considering the lower parental HRQoL and the central role parents play in their children's lives, it is crucial to include prevention and intervention measures for parents as part of a multimodal treatment regime for children with solid pediatric abdominal tumors.

Staging and Restaging Pediatric Abdominal and Pelvic Tumors: A Practical Guide.

The most common abdominal malignancies diagnosed in the pediatric population include neuroblastoma, Wilms tumor, hepatoblastoma, lymphoma, germ cell tumor, and rhabdomyosarcoma. There are distinctive imaging findings and patterns of spread for each of these tumors that radiologists must know for diagnosis and staging and for monitoring the patient's response to treatment. The multidisciplinary treatment group that includes oncologists, surgeons, and radiation oncologists relies heavily on imaging evaluation to identify the best treatment course and prognostication of imaging findings, such as the image-defined risk factors for neuroblastomas, the PRETreatment EXtent of Disease staging system for hepatoblastoma, and the Ann Arbor staging system for lymphomas. It is imperative for radiologists to be able to correctly indicate the best imaging methods for diagnosis, staging, and restaging of each of these most prevalent tumors to avoid inconclusive or unnecessary examinations. The authors review in a practical manner the most updated key points in diagnosing and staging disease and assessing response to treatment of the most common pediatric abdominal tumors. ©RSNA, 2024 Supplemental material is available for this article.

Construction of a prognostic model for autophagy in Wilm's tumor.

Wilm's tumor (WT) is one of the most common childhood urological tumors, ranking second in the incidence of pediatric abdominal tumors. The development of WT is associated with various factors, and the correlation with autophagy is currently unclear. To develop a new prognostic model of autophagy-related genes (ATG) for WT. Using the Therapeutically applicable research to generate effective treatments (TARGET) database to screen for differentially expressed ATGs in WT and normal tissues. ATGs were screened for prognostic relevance to WT using one-way and multifactorial Cox regression analyses and prognostic models were constructed. The risk score was calculated according to the model, and the predictive ability of the constructed model was analyzed using the ROC (receiver operating characteristic) curve to verify the significance of the model for the prognosis of WT. Sixty-eight differentially expressed ATGs were identified by univariate Cox regression analysis, and two critical prognostic ATGs (CXCR4 and ERBB2) were identified by multivariate Cox regression analysis. Patients were divided into high-risk and low-risk groups according to the differential expression of these two ATGs. Kaplan-Meier (KM) curves showed a significant difference in survival time between the two groups. The critical prognostic ATGs were combined with race, age, and stage in a multifactorial regression analysis, and the final prognostic model was produced as a line graph. The prognostic model of autophagy-related genes composed of the CXCR4 gene and ERBB2 gene has a specific predictive value for the prognosis of WT, and the present study provides a clear basis for future research on biomarkers and therapeutic targets.

Imaging of pediatric abdominal soft tissue tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper.

This paper provides imaging recommendations for pediatric abdominal tumors that arise outside of the solid viscera. These tumors are rare in children and have been categorized in two groups: abdominal wall and peritoneal tumors (desmoid tumor and desmoplastic small round cell tumor) and tumors that arise from the gastrointestinal tract (gastrointestinal stromal tumor and gastrointestinal neuroendocrine tumor). Authors offer consensus recommendations for imaging assessment of these tumors at diagnosis, during follow-up, and when off-therapy.

Update on the Role of Imaging in Staging of Common Pediatric Abdominal Tumors

Neuroblastoma, Wilms tumor, and hepatoblastoma are the most common pediatric abdominal malignancies. Management of these diseases is a multidisciplinary process that continues to evolve based on the results of international collaborative trials and advances in understanding of tumor biology. Each of these tumors has unique characteristics and behavior which are reflected in their respective staging systems. It is important for clinicians involved in the care of children with abdominal malignancies to be familiar with current staging guidelines and imaging recommendations. This article reviews the current role of imaging in the management of these common pediatric abdominal malignancies, with emphasis on initial staging.

Pediatric patient-specific three-dimensional virtual models for surgical decision making in resection of hepatic and retroperitoneal tumors.

Typically, preoperative imaging is viewed in two dimensions (2D) only, but three-dimensional (3D) virtual models may improve viewers' anatomical perspective by permitting them to interact with the imaging through manipulating it in space. Research into the utility of these models in most surgical specialties is growing rapidly. This study investigates the utility of 3D virtual models of complex pediatric abdominal tumors for clinical decision making, particularly the decision to proceed with surgical resection or not. 3D virtual models of tumors and adjacent anatomy were created from CT images of pediatric patients scanned for Wilms tumor, neuroblastoma or hepatoblastoma. Pediatric surgeons individually assessed the resectability of the tumors. First, they assessed resectability using the standard protocol of viewing imaging on conventional screens and then reassessed resectability after being presented with the 3D virtual models. Inter-physician agreement on resectability for each patient was analyzed using Krippendorff's alpha. Inter-physician agreement was used as a surrogate for correct interpretation. Participants were also surveyed afterward on the utility and practicality of the 3D virtual models for clinical decision making. Inter-physician agreement when using CT imaging alone was "fair" (Krippendorff's alpha α = 0.399), while inter-physician agreement when using 3D virtual models increased to "moderate" (Krippendorff's alpha α = 0.532). When surveyed about model utility, all 5 participants considered them helpful. Two participants felt the models would be practical for clinical use in most cases, while 3 felt they would be practical for select cases only. This study demonstrates the subjective utility of 3D virtual models of pediatric abdominal tumors for clinical decision making. The models are an adjunct that can be particularly useful in complicated tumors that efface or displace critical structures that may impact resectability. Statistical analysis demonstrates the improved inter-rater agreement with the 3D stereoscopic display over the 2D display. The use of 3D displays of medical images will increase over time, and evaluation of their potential usefulness in various clinical settings is necessary.

A spectrum of findings on computed tomography in paediatric abdominal and pelvic tumours in a Ghanaian teaching hospital.

To review the Computed Tomography( CT )features of pediatric oncological patients with abdominal and pelvic tumours and correlate these findings with their histopathological diagnosis. This was a retrospective cross-sectional facility-based study. This study was conducted in the Pediatric Oncology Unit and Radiology Department of the Korle Bu Teaching Hospital. Fifty-six pediatric oncology patients with contrast-enhanced abdominal and pelvic CT scans. The abdominal and pelvic CT scans findings, patient biodata, and histopathology reports of oncology patients over four years were reviewed. Simple descriptive statistics using frequency distribution, percentages, means, and standard deviation were used to describe the various variables and presented tables. The four commonest tumours were nephroblastoma, neuroblastoma, lymphoma, and hepatoblastoma. The mean age at diagnosis was 4.8 years, with a slightly higher male predominance. The majority of the tumours were extremely large at presentation. Overall, the CT - histopathology concordance was 79.2%. Abdominal and pelvic CT scans play an important role in the diagnostic workup of pediatric malignancies by ensuring early and accurate diagnosis of these tumours. None declared.

Two-cavities approach for resection of pediatric abdominal neuroblastic tumors: experience of a national reference pediatric onco-surgical center

PurposeSurgery of complex neuroblastic tumors often requires additional procedures, especially in the situation of tumor extension within thorax and impossibility of securing the aorta above the tumor. These situations prompt the opening of the thoracic cavity. The concern regarding increased operative trauma and morbidity associated with this approach make surgeons reluctant regarding this technique. The aim of this study was to evaluate the efficacy of two-cavities approach based on our experience in a reference pediatric onco-surgical center.MethodsBetween 2003 and 2021, we operated on 232 neuroblastic tumors. 31/232 patients with complex, advanced-stage neuroblastic tumors underwent tumor resection through a two-cavities approach. A retrospective review of patient’s records was performed.ResultsThe median age at operation was 48 months (5–180). 23/31 patients presented image-defined risk factors (IDRF). The approach most commonly used was the transverse laparotomy with incision of the diaphragm (n = 14), followed by the thoraco-abdominal incision (n = 10). Gross total resection (GTR) was achieved in 24 patients, a near-GTR in 4 cases, and an incomplete resection in 3 cases. Median duration of surgery was 288 min (99–900) and median duration of mechanical ventilation was 22 h (0–336). Postoperative complications occurred in 10 patients, 6/10 required surgical reintervention. The 5-year overall survival (OS) was 90% and the 5-year event-free survival (EFS) was 50%.ConclusionsThe two-cavities approach for resection of abdominal neuroblastoma in children is a safe technique with no added morbidity.

Exosomal miR-214-3p as a potential novel biomarker for rhabdoid tumor of the kidney.

Rhabdoid tumor of the kidney (RTK) is a rare, highly aggressive pediatric renal tumor. No specific biomarkers are available for detection of RTK, and the initial differential diagnosis from other pediatric abdominal tumors, including neuroblastoma (NB), is difficult. Exosomal miRNAs are novel cancer biomarkers that can be detected in biological fluids. We explored candidate RTK-specific exosomal miRNAs as novel biomarkers of RTK. Exosomal miRNAs were collected from conditioned media of human RTK-derived cell lines, a human embryonic renal cell line, and human NB-derived cell lines. miRNA sequencing (miRNA-Seq) was performed to detect candidate RTK-specific exosomal miRNAs. The exosomal miRNA expression in conditioned media of tumor cell lines and serum from RTK xenograft-bearing mice was analyzed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The expression of exosomal miR-214-3p detected by miRNA-Seq was highest in RTK-derived cell lines. Exosomal miR-214-3p expression level determined by qRT-PCR was significantly higher in RTK-derived cell lines than in the human embryonic renal cell line or NB-derived cell lines. Furthermore, the serum exosomal miR-214-3p expression level was significantly higher in RTK xenograft mice than controls. Our data indicated that exosomal miR-214-3p has potential as a novel biomarker of RTK.

Imaging for Staging of Pediatric Abdominal Tumors: An Update, From the AJR Special Series on Cancer Staging.

The three most common pediatric solid tumors of the abdomen are neuroblastoma, Wilms tumor, and hepatoblastoma. These embryonal tumors most commonly present in the first decade of life. Each tumor has unique imaging findings, including locoregional presentation and patterns of distant spread. Neuroblastoma, Wilms tumor, and hepatoblastoma have unique staging systems that rely heavily on imaging and influence surgical and oncologic management. The staging systems include image-defined risk factors for neuroblastoma, the Children's Oncology Group staging system for Wilms tumor, and the pretreatment extent of tumor system (PRETEXT) for hepatoblastoma. It is important for radiologists to be aware of these staging systems to optimize image acquisition and interpretation. This article provides a practical and clinically oriented approach to the role of imaging in the staging of these common embryonal tumors of childhood. The selection among imaging modalities, key findings for determining tumor stage, and the role of imaging in posttreatment response evaluation and surveillance are discussed. Recent updates to the relevant staging systems are highlighted with attention to imaging findings of particular prognostic importance. The information presented will help radiologists tailor the imaging approach to the individual patient and guide optimal oncologic management.

Association Between Arg72Pro Polymorphism in TP53 and Malignant Abdominal Solid Tumor Risk in Hunan Children.

Pediatric solid tumors are heterogeneous and comprise various histological subtypes. TP53, a tumor suppressor, orchestrates the transcriptional activation of anti-cancer genes. The gene coding for this protein is highly polymorphic, and its mutations are associated with cancer development. The Arg72Pro polymorphism in TP53 has been associated with susceptibility to various types of cancer. Here, in this hospital-based study, we evaluated the association of this polymorphism with susceptibility toward malignant abdominal solid tumors in children in the Hunan province of China. We enrolled 162 patients with neuroblastoma, 60 patients with Wilms’ tumor, and 28 patients with hepatoblastoma as well as 270 controls. Genotypes were determined using a TaqMan assay, and the strength of the association was assessed using an odds ratio, within a 95% confidence interval identified using logistic regression models. Our results showed that the Arg72Pro polymorphism did not exhibit significant association with susceptibility toward pediatric malignant abdominal solid tumors. Stratification analysis revealed that this polymorphism exerts weak sex- and age-specific effects on Wilms’ tumor and hepatoblastoma susceptibility, respectively. Overall, our results indicate that the Arg72Pro polymorphism may have a marginal effect on susceptibility toward pediatric malignant abdominal solid tumors in Hunan, and this finding warrants further confirmation.

Deep learning prediction of proton and photon dose distributions for paediatric abdominal tumours

ObjectiveDose prediction using deep learning networks prior to radiotherapy might lead tomore efficient modality selections. The study goal was to predict proton and photon dose distributions based on the patient-specific anatomy and to assess their clinical usage for paediatric abdominal tumours. Material and methodsData from 80 patients with neuroblastoma or Wilms’ tumour was included. Pencil beam scanning (PBS) (5 mm/ 3%) and volumetric-modulated arc therapy (VMAT) plans (5 mm) were robustly optimized on the internal target volume (ITV). Separate 3-dimensional patch-based U-net networks were trained to predict PBS and VMAT dose distributions. Doses, planning-computed tomography images and relevant optimization masks (ITV, vertebra and organs-at-risk) of 60 patients were used for training with a 5-fold cross validation.The networks’ performance was evaluated by computing the relative error between planned and predicted dose-volume histogram (DVH) parameters for 20 inference patients. In addition, the organs-at-risk mean dose difference between modalities was calculated using planned and predicted dose distributions (ΔDmean = DVMAT-DPBS). Two radiation oncologists performed a blind PBS/VMAT modality selection based on either planned or predicted ΔDmean. ResultsAverage DVH differences between planned and predicted dose distributions were ≤ |6%| for both modalities. The networks classified the organs-at-risk Dmean difference as a gain (ΔDmean > 0) with 98% precision. An identical modality selection based on planned compared to predicted ΔDmean was made for 18/20 patients. ConclusionDeep learning networks for accurate prediction of proton and photon dose distributions for abdominal paediatric tumours were established. These networks allowing fast dose visualisation might aid in identifying the optimal radiotherapy technique when experience and/or resources are unavailable.

Utility of cell block preparation in diagnosis of paediatric abdominal neoplasms.

Paediatric abdominal neoplasms are fairly common. Fine needle aspiration cytology (FNAC) is used for the initial evaluation of paediatric abdominal neoplasms. However, sometimes FNA interpretation can be difficult on limited material, owing to tumour heterogeneity and overlapping features. Therefore, we attempted to obtain additional information using cell block (CB) preparation from residual aspiration material along with immunohistochemistry (IHC) to enhance the diagnostic accuracy. To evaluate the correlation between CB preparation and FNAC in diagnosis of paediatric abdominal tumours with the help of an extended panel of IHC markers and to highlight some of the diagnostic difficulties. A total of 113 cases of paediatric abdominal masses were studied. In addition to routine FNA smears, CBs were prepared from the residual material for IHC analysis as considered appropriate. This study included a total of 113 children with abdominal masses. Histopathology following surgical resection was available in 53 cases. Histology was taken as gold standard to measure the diagnostic accuracy with reference to sensitivity (Sn), specificity (Sp), positive predictive value and negative predictive value. The Sn of FNA alone was 87.5% and Sp was 97.78%. The Sn and Sp increased with use of CB alone and were 100% and 97.78% respectively. The highest Sn and Sp were observed when CB was combined with IHC where both the values were 100%. CB with IHC is a useful adjunct to the routine FNA smears that further contributes to enhance the accuracy of the cytopathological diagnosis and is useful for choosing pre-operative chemotherapeutic regimen.

Deep learning-enabled MRI-only photon and proton therapy treatment planning for paediatric abdominal tumours

PurposeTo assess the feasibility of magnetic resonance imaging (MRI)-only treatment planning for photon and proton radiotherapy in children with abdominal tumours. Materials and methodsThe study was conducted on 66 paediatric patients with Wilms’ tumour or neuroblastoma (age 4 ± 2 years) who underwent MR and computed tomography (CT) acquisition on the same day as part of the clinical protocol. MRI intensities were converted to CT Hounsfield units (HU) by means of a UNet-like neural network trained to generate synthetic CT (sCT) from T1- and T2-weighted MR images. The CT-to-sCT image similarity was evaluated by computing the mean error (ME), mean absolute error (MAE), peak signal-to-noise ratio (PSNR) and Dice similarity coefficient (DSC). Synthetic CT dosimetric accuracy was verified against CT-based dose distributions for volumetric-modulated arc therapy (VMAT) and intensity-modulated pencil-beam scanning (PBS). Relative dose differences (Ddiff) in the internal target volume and organs-at-risk were computed and a three-dimensional gamma analysis (2 mm, 2%) was performed. ResultsThe average ± standard deviation ME was −5 ± 12 HU, MAE was 57 ± 12 HU, PSNR was 30.3 ± 1.6 dB and DSC was 76 ± 8% for bones and 92 ± 9% for lungs. Average Ddiff were <0.5% for both VMAT (range [−2.5; 2.4]%) and PBS (range [−2.7; 3.7]%) dose distributions. The average gamma pass-rates were >99% (range [85; 100]%) for VMAT and >96% (range [87; 100]%) for PBS. ConclusionThe deep learning-based model generated accurate sCT from planning T1w- and T2w-MR images. Most dosimetric differences were within clinically acceptable criteria for photon and proton radiotherapy, demonstrating the feasibility of an MRI-only workflow for paediatric patients with abdominal tumours.

Body Composition, Metabolic Health, and Functional Impairment among Adults Treated for Abdominal and Pelvic Tumors during Childhood.

We aimed to characterize body composition, metabolic impairments, and physical performance among survivors of pediatric abdominal and pelvic solid tumors. Participants included 431 survivors of abdominal or pelvic tumors [median attained age = 29.9 (range: 18.7-55.1) years]. Relative lean mass and fat mass were assessed with dual X-ray absorptiometry. Metabolic outcomes [insulin resistance (IR), high-density lipoprotein (HDL), low-density lipoprotein, and triglycerides] were based on laboratory values and medication usage. General linear regression evaluated associations between treatment and lifestyle with body composition; binomial regression evaluated associations between body composition and metabolic outcomes and physical performance. Lean mass was lower than values from the National Health and Nutrition Examination Survey (NHANES) in males (Z-score = -0.67 ± 1.27; P < 0.001) and females (Z-score = -0.72 ± 1.28; P < 0.001). Higher cumulative abdominal and pelvic radiation doses were associated with lower lean mass among males [abdominal: β = -0.22 (SE) ± 0.07; P = 0.002 and pelvic: β = -0.23 ± 0.07; P = 0.002] and females (abdominal: β = -0.30 ± 0.09; P = 0.001 and pelvic: β = -0.16 ± 0.08; P = 0.037). Prevalence of IR (40.6% vs. 33.8%; P = 0.006), low HDL (28.9% vs. 33.5%; P = 0.046), and high triglycerides (18.4% vs. 10.0%; P < 0.001) was increased among survivors relative to NHANES. Compared with survivors with normal/high lean mass and normal/low fat mass, survivors with normal/high lean mass and high fat mass had an increased risk of IR (P < 0.001), low HDL (P < 0.001), reduced quadriceps strength at 60°/second (P < 0.001) and 300°/second (P < 0.001), and reduced distance covered in the 6-minute walk (P < 0.01). Abdominal/pelvic radiotherapy is associated with body composition changes that can adversely influence metabolic outcomes and performance status among survivors. Interventions targeting body composition may facilitate management of cardiovascular disease risk in this population.

Evaluating the benefit of PBS vs. VMAT dose distributions in terms of dosimetric sparing and robustness against inter-fraction anatomical changes for pediatric abdominal tumors

Background and purposeTo evaluate the dosimetric sparing and robustness against inter-fraction anatomical changes between photon and proton dose distributions for children with abdominal tumors. Material and methodsVolumetric modulated arc therapy (VMAT) and intensity-modulated pencil beam scanning (PBS) proton dose distributions were calculated for 20 abdominal pediatric cases (average 3, range 1–8 years). VMAT plans were based on a full-arc while PBS plans on 2–3 posterior-oblique irradiation fields. Plans were robustly optimized on a patient-specific internal target volume (ITV) using a uniform 5 mm set-up uncertainty. Additionally, for the PBS plans a ± 3% proton range uncertainty was accounted for. Fractional dose re-calculations were performed using the planning computed tomography (CT) deformably registered to the daily cone-beam CT (CBCT) images. Fractional doses were accumulated rigidly. Planned and CBCT accumulated VMAT and PBS dose distributions were compared using dose–volume histogram (DVH) parameters. ResultsSignificant better sparing of the organs at risk with a maximum reduction in the mean dose of 40% was achieved with PBS. Mean ITV DVH parameters differences between planned and CBCT accumulated dose distributions were smaller than 0.5% for both VMAT and PBS. However, the ITV coverage (V95% > 99%) was not reached for one patient for the accumulated VMAT dose distribution. ConclusionsFor pediatric patients with abdominal tumors, improved dosimetric sparing was obtained with PBS compared to VMAT. In addition, PBS delivered by posterior-oblique irradiation fields demonstrated to be robust against anatomical inter-fraction changes. Compared to PBS, daily anatomical changes proved to affect the target coverage of VMAT dose distributions to a higher extent.

PO-0986 Inter-fraction anatomical changes in pediatric abdominal tumors during photon and proton therapy

PO-0986 Inter-fraction anatomical changes in pediatric abdominal tumors during photon and proton therapy

Body composition among adult survivors of pediatric abdominal and pelvic tumors in the St. Jude Lifetime Cohort.

10574Background: In the general population, adverse changes in body composition are associated with reduced physical function, metabolic impairment and mortality. However, little is known about cha...

MRI Evaluation of Pediatric Malignant Abdominal Tumors

Mostly, pediatric abdominal tumors are benign. Eventually, malignant cancer may occur as abdominal tumor being the Wilms tumor, neuroblastoma, hepatoblastoma, and Burkitt’s lymphoma found to be common on this age group. Abdominal tumors can have a wide etiology range that can be classified according to its location, age group, and associated signs and symptoms. Mostly, benign findings are hydronephrosis, infectious hepatosplenomegaly, and ascariasis, while neuroblastoma, Wilms tumor, and germ cell tumors can exhibit specific MRI findings helping on its determination. This article discuss some clinical and MRI presentation of main abdominal pediatric malignances, as well as imaging findings that can correlate to clinical aspects to help during staging and patients’ treatment follow up.