Search

Background: Anaplastic sarcoma of the kidney (ASK) is a DICER1-related neoplasm first identified as a distinctive tumor type through the evaluation of unusual cases of putative anaplastic Wilms tumors. Subsequent case reports identified the presence of biallelic DICER1 variants as well as progression from cystic nephroma, a benign DICER1-related neoplasm. Despite increasing recognition of ASK as a distinct entity, the optimal treatment remains unclear., Methods: Individuals with known or suspected DICER1-related tumors including ASK were enrolled in the International Pleuropulmonary Blastoma/DICER1 Registry. Additionally, a comprehensive review of reported cases of ASK was undertaken, and data were aggregated for analysis with the aim to identify prognostic factors and clinical characteristics to guide decisions regarding genetic testing, treatment, and surveillance., Results: Ten cases of ASK were identified in the Registry along with 37 previously published cases. Staging data, per Children's Oncology Group guidelines, was available for 40 patients: 13 were stage I, 12 were stage II, 10 were stage III, and five were stage IV. Outcome data were available for 37 patients. Most (38 of 46) patients received upfront chemotherapy and 14 patients received upfront radiation. Two-year event-free survival (EFS) for stage I-II ASK was 81.8% (95% confidence interval [CI]: 67.2%-99.6%), compared with 46.6% EFS (95% CI: 24.7%-87.8%) for stage III-IV (p = .07). Two-year overall survival (OS) for stage I-II ASK was 88.9% (95% CI: 75.5%-100.0%), compared with 70.0% (95% CI: 46.7%-100.0%) for stage III-IV (p = .20). Chemotherapy was associated with improved EFS and OS with hazard ratios of 0.09 (95% CI: 0.02-0.31) and 0.08 (95% CI: 0.02-0.42), respectively., Conclusion: ASK is a rare DICER1-related renal neoplasm. In the current report, we identify clinical and treatment-related factors associated with outcome including the importance of chemotherapy in treating ASK. Ongoing data collection and genomic analysis are indicated to optimize outcomes for children and adults with these rare tumors., (© 2024 Wiley Periodicals LLC.)

Utilization of tumor-only sequencing has expanded in pediatric cancer patients, which can lead to identification of pathogenic variants in genes that may be germline and/or have uncertain relevance to the tumor in question, such as the homologous recombination (HR) pathway genes BRCA1/2. We identified patients with pathogenic BRCA1/2 mutations from somatic tumor sequencing, and performed additional germline sequencing to assess for the presence of loss of heterozygosity (LOH). Of seven patients identified, four (57.1%) mutations were found in the germline and none had associated LOH. Our data suggest that BRCA1/2 mutations identified in this context are likely incidental findings., (© 2023 The Authors. Pediatric Blood & Cancer published by Wiley Periodicals LLC.)

Pheochromocytoma and paraganglioma (PPGL) are rare neuroendocrine tumors in childhood. Up to 40% of PPGL are currently thought to be associated with a hereditary predisposition. Nuclear medicine imaging modalities such as fluorodeoxyglucose positron emission tomography ( 18 F-FDG PET), 68 Ga-DOTATATE PET, and 123 I-metaiodobenzylguanidine ( 123 I-MIBG) scintigraphy play an essential role in the staging, response assessment, and determination of suitability for targeted radiotherapy in patients with PPGL. Each of these functional imaging modalities targets a different cellular characteristic and as such can be complementary to anatomic imaging and to each other. With the recent US Food and Drug Administration approval and increasing use of 68 Ga-DOTATATE for imaging in children, the purpose of this article is to use a case-based approach to highlight both the advantages and limitations of DOTATATE imaging as it is compared to current radiologic imaging techniques in the staging and response assessment of pediatric PPGL, as well as other neuroendocrine malignancies., (© 2022 Wiley Periodicals LLC.)

Background: Li-Fraumeni syndrome (LFS) is an autosomal dominant hereditary cancer syndrome associated with germline mutations in the TP53 gene and a high risk of childhood-onset malignancies. Cancer surveillance is challenging in pediatric mutation carriers given the anatomic spectrum of malignancies and young age of onset. Whole-body magnetic resonance imaging (WB-MRI) may provide an acceptable method for early cancer detection., Procedure: We conducted a prospective feasibility pilot study of pediatric subjects (age < 18 years) with LFS to determine return rates for annual WB-MRI scan. Secondary objectives included characterization of incident cancers (and how they were detected)., Results: Forty-five WB-MRI scans in 20 subjects were performed over 5 years; two patients enrolled without subsequently undergoing scans. Eighty-nine percent of participants scanned (95% confidence interval: 67-99%) returned for second examinations. Fifty-five percent of participants required general anesthesia, which was well tolerated in all cases. Six patients required dedicated follow-up imaging. One participant required biopsy of a detected brain lesion; pathology demonstrated reactive gliosis. Another participant, with prior choroid plexus carcinoma, had a new brain lesion detected on clinical follow-up MRI not seen on WB-MRI 6 months prior. All other participants remain well (median: 3 years, range: 0.08-4 years)., Conclusions: WB-MRI in pediatric subjects is a well-tolerated approach to cancer surveillance despite the need for general anesthesia in some patients. A large multicenter trial would determine true test characteristics and efficacy of this approach for early cancer detection in children at high cancer risk., (© 2017 Wiley Periodicals, Inc.)

Synchronous cancers are extraordinarily rare in pediatric patients and present a therapeutic challenge. Patient A presented with synchronous unilateral Wilms tumor (WT) and standard-risk (SR) B-precursor acute lymphoblastic leukemia (ALL). Genetic testing revealed bialleleic BRCA2/FANCD1 mutations. Patient B, after SR B-precursor ALL induction therapy, was noted on fever workup to have a renal mass; pathology demonstrated lesion indeterminate between WT and nephrogenic rest. Therapy was customized for each patient to treat both cancers. Both patients have ongoing remission from their cancers, without excessive toxicity. We report two regimens for treating synchronous WT and ALL and recommend screening such patients for cancer predisposition., (© 2016 Wiley Periodicals, Inc.)

Global variations in the incidence of pediatric cancers have been described; however, the causes of such differences are not known. We investigated the relationship between the incidence of embryonal tumors and human development index on a global scale. Increasing incidence of neuroblastoma correlates significantly with an increasing index of human development, with greater incidence among countries with high socioeconomic development, in apparent contrast to the incidence of retinoblastoma. While more data are needed to corroborate this observation, our findings suggest new avenues for etiological research and serve as a call for support of population-based cancer registries in low-middle-income countries., (© 2016 Wiley Periodicals, Inc.)