Pediatric high-grade gliomas and the WHO CNS Tumor Classification - Perspectives of pediatric neuro-oncologists and neuropathologists in light of recent updates

Background: The WHO Classification of Tumors of the Central Nervous System has undergone major restructuring. Molecularly defined diagnostic criteria were introduced in 2016 (revised 4th edition) and expanded in 2021 (5th edition) to incorporate further essential diagnostic molecular parameters. We investigated potential differences between specialists in perception of these molecularly defined subtypes for pediatric high-grade gliomas (pedHGG). Methods: We designed a 22-question survey studying the impact of the revised 4th edition of the WHO classification on pedHGG. Data were collected and statistically analyzed to examine the spectrum of viewpoints and possible differences between neuro-oncologists and neuropathologists. Results: 465 participants from 53 countries were included; 187 pediatric neuro-oncologists (40%), 160 neuropathologists (34%), and 118 additional experts (26%). Neuro-oncologists reported issues with the introduction of molecularly defined tumor types, as well as the abolishment or renaming of established tumor entities, while neuropathologists did not to the same extent. Both groups indicated less relevant or insufficient diagnostic definitions were available in 2016. Reported issues were classified and assessed in the 2021 WHO classification and a substantial improvement was perceived. However, issues of high clinical relevance remain to be addressed, including the definition of clinical phenotypes for diffuse intrinsic pontine glioma and gliomatosis cerebri. Conclusions: Within the WHO classification of pediatric brain tumors, such as pedHGG, rapid changes in molecular characterization have been introduced. This study highlights the ongoing need for cross talk between pathologist and oncologist to advance the classification of pedHGG subtypes and ensure biological relevance and clinical impact

A microRNA prognostic signature in patients with diffuse intrinsic pontine gliomas through non-invasive liquid biopsy

Diffuse midline gliomas (DMGs) originate in the thalamus, brainstem, cerebellum and spine. This entity includes tumors that infiltrate the pons, called diffuse intrinsic pontine gliomas (DIPGs), with a rapid onset and devastating neurological symptoms. Since surgical removal in DIPGs is not feasible, the purpose of this study was to profile circulating miRNA expression in DIPG patients in an effort to identify a non-invasive prognostic signature with clinical impact. Using a high-throughput platform, miRNA expression was profiled in serum samples collected at the time of MRI diagnosis and prior to radiation and/or systemic therapy from 47 patients enrolled in clinical studies, combining nimotuzumab and vinorelbine with concomitant radiation. With progression-free survival as the primary endpoint, a semi-supervised learning approach was used to identify a signature that was also tested taking overall survival as the clinical endpoint. A signature comprising 13 circulating miRNAs was identified in the training set (n = 23) as being able to stratify patients by risk of disease progression (log-rank p = 0.00014; HR = 7.99, 95% CI 2.38–26.87). When challenged in a separate validation set (n = 24), it confirmed its ability to predict progression (log-rank p = 0.00026; HR = 5.51, 95% CI 2.03–14.9). The value of our signature was also confirmed when overall survival was considered (log-rank p = 0.0021, HR = 4.12, 95% CI 1.57–10.8). We have identified and validated a prognostic marker based on the expression of 13 circulating miRNAs that can shed light on a patient’s risk of progression. This is the first demonstration of the usefulness of nucleic acids circulating in the blood as powerful, easy-to-assay molecular markers of disease status in DIPG. This study provides Class II evidence that a signature based on 13 circulating miRNAs is associated with the risk of disease progression

Radiosensitisation by olaparib through focused ultrasound delivery in a diffuse midline glioma model

BACKGROUND AND PURPOSE: Diffuse midline glioma H3K27-altered (DMG) is an aggressive, inoperable, predominantly paediatric brain tumour. Treatment strategies are limited, resulting in a median survival of only 11 months. Currently, radiotherapy (RT), often combined with temozolomide, is considered the standard of care but remains palliative, highlighting the urgency for new therapies. Radiosensitisation by olaparib, an inhibitor of PARP1 and subsequently PAR-synthesis, is a promising treatment option. We assessed whether PARP1 inhibition enhances radiosensitivity in vitro and in vivo following focused ultrasound mediated blood-brain barrier opening (FUS-BBBO). METHODS: Effects of PARP1 inhibition were evaluated in vitro using viability, clonogenic, and neurosphere assays. In vivo olaparib extravasation and pharmacokinetic profiling following FUS-BBBO was measured by LC-MS/MS. Survival benefit of FUS-BBBO combined with olaparib and RT was assessed using a patient-derived xenograft (PDX) DMG mouse model. RESULTS: Treatment with olaparib in combination with radiation delayed tumour cell proliferation in vitro through the reduction of PAR. Prolonged exposure of low olaparib concentration was more efficient in delaying cell growth than short exposure of high concentration. FUS-BBBO increased olaparib bioavailability in the pons by 5.36-fold without observable adverse effects. A Cmax of 54.09 μM in blood and 1.39 μM in the pontine region was achieved following administration of 100 mg/kg olaparib. Although RT combined with FUS-BBBO mediated olaparib extravasation delayed local tumour growth, survival benefits were not observed in an in vivo DMG PDX model. CONCLUSIONS: Olaparib effectively radiosensitises DMG cells in vitro and reduces primary tumour growth in vivo when combined with RT. Further studies are needed to investigate the therapeutic benefit of olaparib in suitable preclinical PDX models

Development of the SIOPE DIPG network, registry and imaging repository : a collaborative effort to optimize research into a rare and lethal disease

Diffuse intrinsic pontine glioma (DIPG) is a rare and deadly childhood malignancy. After 40 years of mostly single-center, often non-randomized trials with variable patient inclusions, there has been no improvement in survival. It is therefore time for international collaboration in DIPG research, to provide new hope for children, parents and medical professionals fighting DIPG. In a first step towards collaboration, in 2011, a network of biologists and clinicians working in the field of DIPG was established within the European Society for Paediatric Oncology (SIOPE) Brain Tumour Group: the SIOPE DIPG Network. By bringing together biomedical professionals and parents as patient representatives, several collaborative DIPG-related projects have been realized. With help from experts in the fields of information technology, and legal advisors, an international, web-based comprehensive database was developed, The SIOPE DIPG Registry and Imaging Repository, to centrally collect data of DIPG patients. As for April 2016, clinical data as well as MR-scans of 694 patients have been entered into the SIOPE DIPG Registry/Imaging Repository. The median progression free survival is 6.0 months (95% Confidence Interval (CI) 5.6-6.4 months) and the median overall survival is 11.0 months (95% CI 10.5-11.5 months). At two and five years post-diagnosis, 10 and 2% of patients are alive, respectively. The establishment of the SIOPE DIPG Network and SIOPE DIPG Registry means a paradigm shift towards collaborative research into DIPG. This is seen as an essential first step towards understanding the disease, improving care and (ultimately) cure for children with DIPG.Peer reviewe

Clinical, Radiologic, Pathologic, and Molecular Characteristics of Long-Term Survivors of Diffuse Intrinsic Pontine Glioma (DIPG): A Collaborative Report From the International and European Society for Pediatric Oncology DIPG Registries.

Purpose Diffuse intrinsic pontine glioma (DIPG) is a brainstem malignancy with a median survival of 10 years (11% v 3% and 33% v 23%, respectively; P < .001) and with longer symptom duration ( P < .001). STSs, compared with LTSs, more commonly presented with cranial nerve palsy (83% v 73%, respectively; P = .008), ring enhancement (38% v 23%, respectively; P = .007), necrosis (42% v 26%, respectively; P = .009), and extrapontine extension (92% v 86%, respectively; P = .04). LTSs more commonly received systemic therapy at diagnosis (88% v 75% for STSs; P = .005). Biopsies and autopsies were performed in 299 patients (30%) and 77 patients (10%), respectively; 181 tumors (48%) were molecularly characterized. LTSs were more likely to harbor a HIST1H3B mutation (odds ratio, 1.28; 95% CI, 1.1 to 1.5; P = .002). Conclusion We report clinical, radiologic, and molecular factors that correlate with survival in children and young adults with DIPG, which are important for risk stratification in future clinical trials

Hersentumoren op kinderleeftijd

Brain tumors are the second most common form of childhood cancer after leukemia. Most frequently observed symptoms at presentation are headache, nausea and vomiting, abnormalities of gait and coordination, papilledema and seizures. Diagnostics include neuroimaging using MRI and histological classification. The most common pediatric brain tumors are astrocytomas - including optic pathway gliomas and diffuse intrinsic pontine gliomas-, medulloblastomas, ependymomas and craniopharyngiomas. Treatment consists of neurosurgery, (chemo)radiotherapy and/or chemotherapy, depending on the diagnosis. The five year survival rate of children with brain tumors has increased from 58 to 74% during the last decades. However, up to 82% of survivors suffer from late effects of disease and treatment. Improvement of classification systems and development of novel treatment strategies should lead to further improvement of survival rates and reduction of late effects

Adaptive behavior impaired in children with low-grade glioma

Background: Adaptive behavior, i.e., the performance on daily activities required for personal and social independence, is essential to estimate in children with low-grade glioma (LGG) since most of them are long-term survivors. Our aim was to investigate adaptive behavior in children with LGG. Methods: In a cross-sectional study, adaptive behavior was assessed using the paper pencil version of the Parent Form of the Vineland Adaptive Behavior Scales 2nd edition (VABS-II) testing communication, daily living skills, social skills, and motor skills. Scores of children with LGG, younger than 20 years, and diagnosed between 2004 and 2014 were compared with family controls. Correlations between clinical variables and adaptive behavior were explored. Results: Fifty-six children with LGG (median age, 12.1 years; 52% male) and 46 controls (median age, 11.0 years; 43% male) were included in the analyses. Compared with controls, the LGG group was more impaired on total adaptive behavior, communication, and motor skills and in the subdomain gross motor skills (effect sizes d, 0.64–0.86, P < 0.003). Younger age at diagnosis (r = −0.357, P < 0.01) and chemotherapy (r = −0.342, P < 0.05) were associated with poorer motor skills. Residual disease was associated with poorer total adaptive behavior (r = −0.282, P < 0.05). No other significant correlations were found. Conclusion: At the group level, adaptive functioning of children with LGG is impaired compared with family controls. Regular structured monitoring of adaptive behavior is recommended to be able to define the needs for tailored rehabilitation in daily life at home as well as at school

Crowdfunding : En studie om vad som kännetecknar designen av en lyckad kampanj

Crowdfunding som ett sätt att söka finansiering och marknadsföring för en idé eller en produkt har vuxit enormt de senaste åren. Det har dock visat sig att det inte är så lätt att lyckas med sin kampanj. På crowdfundingsajten Kickstarter ligger just nu antalet lyckosamma kampanjer på endast 39,5 %. Syftet med detta arbete har därför varit att undersöka vad som krävs i form av förutsättningar, planering och erfarenheter för att lyckas, liksom vad som får människor att vilja stödja en kampanj. Tidigare forskning inom området har studerats och intervjuer har genomförts med sex personer som har erfarenhet av att ha drivit lyckade kampanjer. Resultatet visade att en av de viktigaste aspekterna för att lyckas är att försöka förmedla trovärdighet och kvalité på sin kampanj och sin produkt. Därefter har data från avslutade lyckade kampanjer på crowdfundingsajten Kickstarter samlats in och bearbetats kvantitativt. Resultatet visade på en signifikant skillnad i procent av slutligt uppnådd målsumma beroende på om kampanjen nådde sitt mål inom 1-2 dagar eller först efter  4-7 dagar.