The transcriptional landscape of Shh medulloblastoma.

Sonic hedgehog medulloblastoma encompasses a clinically and molecularly diverse group of cancers of the developing central nervous system. Here, we use unbiased sequencing of the transcriptome across a large cohort of 250 tumors to reveal differences among molecular subtypes of the disease, and demonstrate the previously unappreciated importance of non-coding RNA transcripts. We identify alterations within the cAMP dependent pathway (GNAS, PRKAR1A) which converge on GLI2 activity and show that 18% of tumors have a genetic event that directly targets the abundance and/or stability of MYCN.

Pattern of Relapse and Treatment Response in WNT-Activated Medulloblastoma.

Over the past decade, wingless-activated (WNT) medulloblastoma has been identified as a candidate for therapy de-escalation based on excellent survival; however, a paucity of relapses has precluded additional analyses of markers of relapse. To address this gap in knowledge, an international cohort of 93 molecularly confirmed WNT MB was assembled, where 5-year progression-free survival is 0.84 (95%, 0.

Recurrent noncoding U1 snRNA mutations drive cryptic splicing in SHH medulloblastoma.

In cancer, recurrent somatic single-nucleotide variants-which are rare in most paediatric cancers-are confined largely to protein-coding genes. Here we report highly recurrent hotspot mutations (r.3A>G) of U1 spliceosomal small nuclear RNAs (snRNAs) in about 50% of Sonic hedgehog (SHH) medulloblastomas.

Desmoplastic Infantile Ganglioglioma: A MAPK Pathway-Driven and Microglia/Macrophage-Rich Neuroepithelial Tumor.

MAPK pathway activation has been recurrently observed in desmoplastic infantile ganglioglioma/astrocytoma (DIG/DIA) with reported disproportionally low mutation allele frequencies relative to the apparent high tumor content, suggesting that MAPK pathway alterations may be subclonal. We sought to expand the number of molecularly profiled cases and investigate if tumor cell composition could account for the observed low mutation allele frequencies. Molecular (targeted neuro-oncology next-generation sequencing/RNA sequencing and OncoScan microarray) and immunohistochemical (CD68-PGM1/CD163/CD14/CD11c/lysozyme/CD3/CD20/CD34/PD-L1) studies were performed in 7 DIG.

Case-based review: atypical teratoid/rhabdoid tumor.

Atypical teratoid/rhabdoid tumor (AT/RT) is a rare CNS cancer that typically occurs in children younger than 3 years of age. Histologically, AT/RTs are embryonal tumors that contain a rhabdoid component as well as areas with primitive neuroectodermal, mesenchymal, and epithelial features. Compared to other CNS tumors of childhood, AT/RTs are characterized by their rapid growth, short symptomatic prodrome, and large size upon presentation, often leading to brain compression and intracranial hypertension requiring urgent intervention.

Heterogeneity within the PF-EPN-B ependymoma subgroup.

Posterior fossa ependymoma comprise three distinct molecular variants, termed PF-EPN-A (PFA), PF-EPN-B (PFB), and PF-EPN-SE (subependymoma). Clinically, they are very disparate and PFB tumors are currently being considered for a trial of radiation avoidance. However, to move forward, unraveling the heterogeneity within PFB would be highly desirable.

Anaplastic astrocytoma with piloid features, a novel molecular class of IDH wildtype glioma with recurrent MAPK pathway, CDKN2A/B and ATRX alterations.

Tumors with histological features of pilocytic astrocytoma (PA), but with increased mitotic activity and additional high-grade features (particularly microvascular proliferation and palisading necrosis) have often been designated anaplastic pilocytic astrocytomas. The status of these tumors as a separate entity has not yet been conclusively demonstrated and molecular features have only been partially characterized. We performed DNA methylation profiling of 102 histologically defined anaplastic pilocytic astrocytomas.

Cross-Cultural Medical Care Training and Education: a National Survey of Pediatric Hematology/Oncology Fellows-in-Training and Fellowship Program Directors.

Pediatric hematologists/oncologists face complex situations such as breaking bad news, treatment/clinical trials discussions, and end-of-life/hospice care. With increasing diversity in patient and physician populations, cultural competency and sensitivity training covering different aspects of pediatric hematology/oncology (PDHO) care can help improve health care delivery and reduce disparities. Though it is considered a required component of fellowship training, there is no clearly defined curriculum meant specifically for PDHO fellows-in-training (PDHO-F).

Intertumoral Heterogeneity within Medulloblastoma Subgroups.

While molecular subgrouping has revolutionized medulloblastoma classification, the extent of heterogeneity within subgroups is unknown. Similarity network fusion (SNF) applied to genome-wide DNA methylation and gene expression data across 763 primary samples identifies very homogeneous clusters of patients, supporting the presence of medulloblastoma subtypes. After integration of somatic copy-number alterations, and clinical features specific to each cluster, we identify 12 different subtypes of medulloblastoma.

Recurrent copy number alterations in low-grade and anaplastic pleomorphic xanthoastrocytoma with and without BRAF V600E mutation.

Pleomorphic xanthoastrocytoma (PXA) is a rare localized glioma characterized by frequent BRAF V600E mutation and CDKN2A/B deletion. We explored the association of copy-number variants (CNVs) with BRAF mutations, tumor grade, and patient survival in a cohort of 41 PXA patients using OncoScan chromosomal microarray. Primary resection specimens were available in 38 cases, including 24 PXA and 14 anaplastic PXA (A-PXA), 23 BRAF V600E mutant tumors (61%).

Molecular Modeling and Functional Analysis of Exome Sequencing-Derived Variants of Unknown Significance Identify a Novel, Constitutively Active FGFR2 Mutant in Cholangiocarcinoma.

Purpose: Genomic testing has increased the quantity of information available to oncologists. Unfortunately, many identified sequence alterations are variants of unknown significance (VUSs), which thus limit the clinician's ability to use these findings to inform treatment. We applied a combination of in silico prediction and molecular modeling tools and laboratory techniques to rapidly define actionable VUSs.

A retrospective review of pediatric antiphospholipid syndrome and thrombosis outcomes.

: Pediatric antiphospholipid syndrome (APS) is characterized by vascular thromboses and multisystem involvement associated with persistently positive antiphospholipid antibodies testing. There is limited literature regarding risk factors for development of thrombosis and long-term thrombotic outcomes in pediatric APS. The objective of our study was to review our institutional experience with pediatric APS and thrombosis outcomes.

Therapeutic Impact of Cytoreductive Surgery and Irradiation of Posterior Fossa Ependymoma in the Molecular Era: A Retrospective Multicohort Analysis.

Purpose: Posterior fossa ependymoma comprises two distinct molecular variants termed EPN_PFA and EPN_PFB that have a distinct biology and natural history. The therapeutic value of cytoreductive surgery and radiation therapy for posterior fossa ependymoma after accounting for molecular subgroup is not known.

Methods: Four independent nonoverlapping retrospective cohorts of posterior fossa ependymomas (n = 820) were profiled using genome-wide methylation arrays.

Prognostic value of medulloblastoma extent of resection after accounting for molecular subgroup: a retrospective integrated clinical and molecular analysis.

Background: Patients with incomplete surgical resection of medulloblastoma are controversially regarded as having a marker of high-risk disease, which leads to patients undergoing aggressive surgical resections, so-called second-look surgeries, and intensified chemoradiotherapy. All previous studies assessing the clinical importance of extent of resection have not accounted for molecular subgroup. We analysed the prognostic value of extent of resection in a subgroup-specific manner.

Neonatal renal vein thrombosis: role of anticoagulation and thrombolysis--an institutional review.

Neonatal renal vein thrombosis (NRVT) is a rare thromboembolic complication in the neonatal period, and sequelae from renal dysfunction can cause significant morbidity. The authors retrospectively reviewed 10 patients with NRVT treated at their institution. The majority of the cohort were male (n = 9), preterm (n = 6), and had unilateral NRVT (n = 6).

Clinical outcomes of children and adults with central nervous system primitive neuroectodermal tumor.

Central nervous system primitive neuroectodermal tumors (CNS PNETs) predominantly occur in children and rarely in adults. Because of the rarity of this tumor, its outcomes and prognostic variables are not well characterized. The purpose of this study was to evaluate clinical outcomes and prognostic factors for children and adults with CNS PNET.

Advances in the management of low-grade gliomas.

Low-grade gliomas (LGGs) represent the most common childhood brain tumors and are a histologically heterogenous group of tumors. Most LGGs are surgically resectable with excellent 10-year overall survival outcomes of more than 90 % with surgery alone. Tumors not amenable to surgical resection and those with an aggressive biology are more challenging to treat.

Bilateral temporal bone langerhans cell histiocytosis: radiologic pearls.

Langerhans cell histiocytosis (LCH) is a rare histiocytic disorder with an unpredictable clinical course and highly varied clinical presentation ranging from single system to multisystem involvement. Although head and neck involvement is common in LCH, isolated bilateral temporal bone involvement is exceedingly rare. Furthermore, LCH is commonly misinterpreted as mastoiditis, otitis media and otitis externa, delaying diagnosis and appropriate therapeutic management.