DNA methylation-array interlaboratory comparison trial demonstrates highly reproducible paediatric CNS tumour classification across 13 international centres.

Aims: DNA methylation profiling, recently endorsed by the World Health Organisation (WHO) as a pivotal diagnostic tool for brain tumours, most commonly relies on bead arrays. Despite its widespread use, limited data exist on the technical reproducibility and potential cross-institutional differences. The LOGGIC Core BioClinical Data Bank registry conducted a prospective laboratory comparison trial with 12 international laboratories to enhance diagnostic accuracy for paediatric low-grade gliomas, focusing on technical aspects of DNA methylation data generation and profile interpretation under clinical real-time conditions.

Optimizing reirradiation for relapsed medulloblastoma: identifying the ideal patient and tumor profiles.

Background: First-line therapies for medulloblastoma(MBL) are obtaining higher survival-rates while decreasing late-effects, but treatment at relapse is not standardized. We report here the experience with MBL re-irradiation(re-RT), its timing and outcome in different clinical settings and tumor groups.

Methods: Patient's staging/treatment at diagnosis, histotypes/molecular subgroups, relapse site/s, re-treatments outcome are reported.

Case report of a pediatric medulloblastoma with concurrent MYC and MYCN subclonal amplification in distinct populations of neoplastic cells.

Medulloblastomas (MDBs) are classified into molecular groups showing peculiar immunohistochemical and genetic features and distinct DNA methylation profile. Group 3 and group 4 MDBs have the worst prognosis; the former is treated with high-risk protocols and features MYC amplification, whereas the latter receives standard-risk protocols and harbors MYCN amplification. Herein, we report a unique case of MDB showing histological and immunohistochemical features consistent with non-SHH/non-WNT classic MDB, with both MYCN (30% of tumor cells) and MYC (5-10% tumor cells) amplification in distinct subclones of neoplastic cells at fluorescence in situ hybridization (FISH), characterized by specific patterns.

Optimizing biomarkers for accurate ependymoma diagnosis, prognostication, and stratification within International Clinical Trials: A BIOMECA study.

Background: Accurate identification of brain tumor molecular subgroups is increasingly important. We aimed to establish the most accurate and reproducible ependymoma subgroup biomarker detection techniques, across 147 cases from International Society of Pediatric Oncology (SIOP) Ependymoma II trial participants, enrolled in the pan-European "Biomarkers of Ependymoma in Children and Adolescents (BIOMECA)" study.

Methods: Across 6 European BIOMECA laboratories, we evaluated epigenetic profiling (DNA methylation array); immunohistochemistry (IHC) for nuclear p65-RELA, H3K27me3, and Tenascin-C; copy number analysis via fluorescent in situ hybridization (FISH) and MLPA (1q, CDKN2A), and MIP and DNA methylation array (genome-wide copy number evaluation); analysis of ZFTA- and YAP1-fusions by RT-PCR and sequencing, Nanostring and break-apart FISH.

Mutations and Pediatric High-Grade Gliomas: A Comparative Genomic Study in Primary and Recurrent Tumors.

Pediatric high-grade gliomas represent a heterogeneous group of tumors with a wide variety of molecular features. We performed whole exome sequencing and methylation profiling on matched primary and recurrent tumors from four pediatric patients with hemispheric high-grade gliomas. Genetic analysis showed the presence of some variants shared between primary and recurrent tumors, along with other variants exclusive of primary or recurrent tumors.

Paediatric-type diffuse high-grade gliomas in the 5th CNS WHO Classification.

As a relevant element of novelty, the fifth CNS WHO Classification highlights the distinctive pathobiology underlying gliomas arising primarily in children by recognizing for the first time the families of paediatric-type diffuse gliomas, both high-grade and low-grade. This review will focus on the family of paediatric-type diffuse high-grade gliomas, which includes four tumour types: 1) Diffuse midline glioma H3 K27-altered; 2) Diffuse hemispheric glioma H3 G34-mutant; 3) Diffuse paediatric-type high-grade glioma H3-wildtype and IDH-wildtype; and 4) Infant-type hemispheric glioma. The essential and desirable diagnostic criteria as well as the entities entering in the differential will be discussed for each tumour type.

A Custom DNA-Based NGS Panel for the Molecular Characterization of Patients With Diffuse Gliomas: Diagnostic and Therapeutic Applications.

The management of patients with Central Nervous System (CNS) malignancies relies on the appropriate classification of these tumors. Recently, the World Health Organization (WHO) has published new criteria underlining the importance of an accurate molecular characterization of CNS malignancies, in order to integrate the information generated by histology. Next generation sequencing (NGS) allows single step sequencing of multiple genes, generating a comprehensive and specific mutational profile of the tumor tissue.

Alternative Lengthening of Telomeres (ALT) and Telomerase Reverse Transcriptase Promoter Methylation in Recurrent Adult and Primary Pediatric Pituitary Neuroendocrine Tumors.

Neoplastic cells acquire the ability to proliferate endlessly by maintaining telomeres via telomerase, or alternative lengthening of telomeres (ALT). The role of telomere maintenance in pituitary neuroendocrine tumors (PitNETs) has yet to be thoroughly investigated. We analyzed surgical samples of 24 adult recurrent PitNETs (including onset and relapses for 14 of them) and 12 pediatric primary PitNETs.

Treatment and outcome of intracranial ependymoma after first relapse in the 2nd AIEOP protocol.

Background: More than 40% of patients with intracranial ependymoma need a salvage treatment within 5 years after diagnosis, and no standard treatment is available as yet. We report the outcome after first relapse of 64 patients treated within the 2nd AIEOP protocol.

Methods: We considered relapse sites and treatments, that is, various combinations of complete/incomplete surgery, if followed by standard or hypofractionated radiotherapy (RT) ± chemotherapy (CT).

Correction: Visani et al. miR-196B-5P and miR-200B-3P Are Differentially Expressed in Medulloblastomas of Adults and Children. 2020, , 265.

The authors wish to make the following corrections to this paper [...

Improvement of the Collection, Maintenance, and Analysis of Neoplastic Cells from Urine Specimens with the Use of CytoMatrix.

Urine cytology is a non-invasive test used in combination with cystoscopy for screening and follow-up of urothelial carcinoma (UC). Although cytology can be used to efficiently identify high-grade UC, it has a lower accuracy for the diagnosis of low-grade UC or patients with presence of atypical urothelial cells (AUC). For these reasons, ancillary tests have been added to urine cytology in order to improve the accuracy.

Correlation Between Immunohistochemistry and Sequencing in H3G34-Mutant Gliomas.

Recurrent glycine-to-arginine/valine alterations at codon 34 (G34R/V) within H3F3A gene characterize a subset of hemispheric high-grade gliomas (HGG) affecting children and young adults. These tumors, defined as G34R/V-mutant gliomas, are histologically heterogenous, with microscopic features of either HGG or embryonal tumors (primitve neuroectodermal tumor-like features). To assess the value of immunohistochemistry (IHC) to detect G34R/V-mutated cases, we tested anti-histone G34V (clone 329E5) and anti-histone G34R (clone RM240) antibodies in a series of 28 formalin-fixed and paraffin-embedded samples.

Second series by the Italian Association of Pediatric Hematology and Oncology of children and adolescents with intracranial ependymoma: an integrated molecular and clinical characterization with a long-term follow-up.

Background: A prospective 2002-2014 study stratified 160 patients by resection extent and histological grade, reporting results in 2016. We re-analyzed the series after a median of 119 months, adding retrospectively patients' molecular features.

Methods: Follow-up of all patients was updated.

Alternative lengthening of telomeres in molecular subgroups of paediatric high-grade glioma.

Purpose: The maintenance of telomere length prevents cancer cell senescence and occurs via two mutually exclusive mechanisms: (a) reactivation of telomerase expression and (b) activation of alternative lengthening of telomeres (ALT). ALT is frequently related to alterations on ATRX, a chromatin-remodelling protein. Recent data have identified different molecular subgroups of paediatric high-grade glioma (pHGG) with mutations of H3F3A, TERTp and ATRX; however, differences in telomere length among these molecular subgroups were not thoroughly examined.

Reduced-dose craniospinal irradiation is feasible for standard-risk adult medulloblastoma patients.

Introduction: Medulloblastoma is the most common malignant brain tumor in children, but accounts for only 1% of brain cancers in adults. For standard-risk pediatric medulloblastoma, current therapy includes craniospinal irradiation (CSI) at reduced doses (23.4 Gy) associated with chemotherapy.

Retrospective analysis on the consistency of MRI features with histological and molecular markers in diffuse intrinsic pontine glioma (DIPG).

Purpose: The diagnosis of diffuse intrinsic pontine glioma (DIPG) is based largely on a combination of clinical and radiological findings due to the difficulty of obtaining a biopsy. An accurate evaluation of magnetic resonance imaging (MRI) scans is consequently essential. Recent analyses on the genomic landscape of DIPG revealed recurrent mutations in the H3F3A and HIST1H3B histone genes.

Telomere elongation via alternative lengthening of telomeres (ALT) and telomerase activation in primary metastatic medulloblastoma of childhood.

Purpose: Elongation of telomeres is necessary for tumor cell immortalization and senescence escape; neoplastic cells use to alternative pathways to elongate telomeres: telomerase reactivation or a telomerase-independent mechanism termed alternative lengthening of telomeres (ALT). Telomerase and ALT pathway has been explored in adult and pediatric gliomas and medulloblastomas (MDBs); however, these mechanisms were not previously investigated in MDBs metastatic at the onset. Therefore, we analyzed the activation of telomerase and ALT pathway in a homogenous cohort of 43 pediatric metastatic medulloblastomas, to investigate whether telomere elongation could play a role in the biology of metastatic MDB.

Non-conventional fotemustine schedule as second-line treatment in recurrent malignant gliomas: Survival across disease and treatment subgroup analysis and review of the literature.

Fotemustine (FTM) is a treatment option in recurrent malignant gliomas (MGs) after first-line Stupp treatment. The efficacy and the safety of fractionated FTM schedule proposed by Addeo was analysed in the present study in recurrent MGs patients. A retrospective analysis on 40 recurrent MGs patients and second-line fractionated FTM chemotherapy was performed.

Pediatric intracranial ependymoma: correlating signs and symptoms at recurrence with outcome in the second prospective AIEOP protocol follow-up.

Purpose: The aims of patients' radiological surveillance are to: ascertain relapse; apply second-line therapy; accrue patients in phase 1/2 protocols if second-line therapy is not standardized/curative; and assess/treat iatrogenic effects. To lessen the emotional and socioeconomic burdens for patients and families, we ideally need to establish whether scheduled radiological surveillance gives patients a better outcome than waiting for symptoms and signs to appear.

Methods: We analyzed a prospective series of 160 newly-diagnosed and treated pediatric/adolescent patients with intracranial ependymoma, comparing patients with recurrent disease identified on scheduled MRI (the RECPT group; 34 cases) with those showing signs/symptoms of recurrent disease (the SYMPPT group; 16 cases).

Correction to: Results of nimotuzumab and vinorelbine, radiation and re-irradiation for diffuse pontine glioma in childhood.

The therapeutic experience reported in the paper was conceived after the use of nimotuzumab and radiotherapy (BSCPED-05 international multicentric trial, EUDRACT 2005-003100-11) in 2009 when we decided to explore the activity of the same combination plus vinorelbine (see the paper for the rationale).