Incidence and survival trends for medulloblastomas in the United States from 2001 to 2013

Epidemiological trends and factors associated with survival in patients with medulloblastoma: A 45-year population-based retrospective study

Medulloblastoma (MB) is a primary brain malignancy. However, updated epidemiological data and long-term outcomes are lacking.The clinical and epidemiological datasets of patients with MB in the current study were obtained from the Surveillance, Epidemiology, and End Results (SEER) databases. Joinpoint regression models were used to assess the rate of changes in the incidence, prevalence, and treatment trends in patients with MB. Cox hazard and competition risk model analyses were used to assess overall survival (OS) and cancer-specific survival (CSS).The age-adjusted incidence of MB remained relatively stable at 0.15 per 100,000 individuals in 2019. The annual percentage change (APC) of females remained stable, whereas that of males increased over time. The 20-year limited-duration prevalence of patients with MB increased significantly from 0.00016 % in 1999 to 0.00203 % in 2018. Patients aged 5-19 years accounted for 46.7 % of all age groups, and the trend for the three treatments was increased. Average annual percentage change (AAPC) for the chemotherapy group was increased in patients aged 20 + years MB [AAPC = 2.66 (95 % CI 0.93-6.31)]. Multivariate analysis revealed that OS and CSS varied significantly according to age, year of diagnosis, histology, stage, surgery, and radiotherapy. Subgroup analysis showed that chemotherapy was associated with a favorable prognosis in high-risk groups.The incidence of MB remained relatively stable, and its prevalence increased significantly. This current population-based study further identified the prognostic factors in patients with MB. Moreover, the use of chemotherapy was associated with better survival in high-risk groups.

Medulloblastoma in adults: an analysis of clinico-pathological, molecular and treatment factors

BACKGROUND

Medulloblastoma is a highly malignant, embryonal tumor, which is rare in adults, and shows distinct clinical, histopathological, molecular and treatment response features.

METHODS

We retrospectively investigated 44 adults (age 17-48 years) with a histological diagnosis of medulloblastoma, and in 23 immunohistochemistry was used to identify the molecular subgroups. We analyzed demographic, diagnostic, therapeutic and cognitive data, and correlated with PFS (progression-free-survival) and OS (overall survival).

RESULTS

We observed a male prevalence and a median age of 31 years. Symptoms at onset were related to infratentorial location, while myeloradicular and/or cranial nerve involvement was rare. Histological examination showed the classic variant in 75% of patients, the desmoplastic/nodular in 23% and the anaplastic in one. As for molecular diagnosis, 17 patients were SHH and 6 non-WNT/non-SHH (5 group 4 and 1 group 3), while no WNT subgroup was found. The SHH subgroup had a prevalence of high-risk patients and leptomeningeal involvement. Patients underwent gross total or subtotal/partial resection, and craniospinal irradiation, followed in 20 cases by adjuvant chemotherapy. Median OS and PFS were 16.9 and 12 years, respectively. Metastatic disease at presentation and subtotal/partial resection were associated with worse prognosis, while the addition of chemotherapy did not yield a significant advantage over radiotherapy alone. Cognitive impairment in long-term survivors was limited and late relapses occurred in 15% of patients.

CONCLUSIONS

Future studies with adequate sample size and long-term follow-up should prospectively investigate the role of surgery and adjuvant therapies across the different molecular subgroups to see whether a personalized approach is feasible.

Chemotherapy in pediatric brain tumor and the challenge of the blood-brain barrier

BACKGROUND

Pediatric brain tumors (PBT) stand as the leading cause of cancer-related deaths in children. Chemoradiation protocols have improved survival rates, even for non-resectable tumors. Nonetheless, radiation therapy carries the risk of numerous adverse effects that can have long-lasting, detrimental effects on the quality of life for survivors. The pursuit of chemotherapeutics that could obviate the need for radiotherapy remains ongoing. Several anti-tumor agents, including sunitinib, valproic acid, carboplatin, and panobinostat, have shown effectiveness in various malignancies but have not proven effective in treating PBT. The presence of the blood-brain barrier (BBB) plays a pivotal role in maintaining suboptimal concentrations of anti-cancer drugs in the central nervous system (CNS). Ongoing research aims to modulate the integrity of the BBB to attain clinically effective drug concentrations in the CNS. However, current findings on the interaction of exogenous chemical agents with the BBB remain limited and do not provide a comprehensive explanation for the ineffectiveness of established anti-cancer drugs in PBT.

METHODS

We conducted our search for chemotherapeutic agents associated with the blood-brain barrier (BBB) using the following keywords: Chemotherapy in Cancer, Chemotherapy in Brain Cancer, Chemotherapy in PBT, BBB Inhibition of Drugs into CNS, Suboptimal Concentration of CNS Drugs, PBT Drugs and BBB, and Potential PBT Drugs. We reviewed each relevant article before compiling the information in our manuscript. For the generation of figures, we utilized BioRender software.

FOCUS

We focused our article search on chemical agents for PBT and subsequently investigated the role of the BBB in this context. Our search criteria included clinical trials, both randomized and non-randomized studies, preclinical research, review articles, and research papers.

FINDING

Our research suggests that, despite the availability of potent chemotherapeutic agents for several types of cancer, the effectiveness of these chemical agents in treating PBT has not been comprehensively explored. Additionally, there is a scarcity of studies examining the role of the BBB in the suboptimal outcomes of PBT treatment, despite the effectiveness of these drugs for other types of tumors.

Global trends, gaps, and future agenda in medulloblastoma research: a bibliometric analysis

BACKGROUND

Medulloblastoma is the most common malignant primary pediatric brain tumor. Over the years, an increase in published research has been observed on this topic. However, there is a lack of analysis on the characteristics and trends and the socioeconomic indicators associated with medulloblastoma research productivity and impact.

METHODS

The Scopus database was used to search all articles from inception to 2020. Bibliometric information was obtained from Scopus, and bibliometrics diagrams were created using VOSviewer software. Statistical analysis was performed using the GraphPad Prism software version 7.

RESULTS

A total of 4058 research articles on medulloblastoma research worldwide were included in this study. There has been an increase in published articles, with a steep increase observed in the last decade. The country with the most publications is the USA, with St. Jude Children's Research Hospital as the most productive institution in medulloblastoma research. The articles mainly focused on molecular biology, diagnosis, treatment, prognostic factors for medulloblastoma, and research on other pediatric tumors. The number of collaborations with other countries showed the strongest positive correlation with scientific productivity.

CONCLUSION

This analysis showed the trend and characteristics of published articles. The results of this study emphasized the need to increase funding for research, support for researchers and physicians, and promote more collaborations with countries and institutions engaged in medulloblastoma research.

Medulloblastomas, CNS embryonal tumors, and cerebellar mutism syndrome: advances in care and future directions

Central nervous system (CNS) embryonal tumors, commonly found in pediatric patients, represent a heterogeneous mix of lesions with an overall poor (though improving) prognosis. Medulloblastomas are by far the most frequently encountered and most widely studied subtype, though others include atypical teratoid/rhabdoid tumors (AT/RTs), embryonal tumor with multilayered rosettes (ETMRs), and CNS neuroblastomas, FOX-R2 activated. The classification, diagnosis, and treatment of these lesions have evolved drastically over the years as their molecular underpinnings have been elucidated. We describe the most recent 2021 WHO Classification system, discuss current understanding of the genetic basis, and demonstrate current thinking in treatment for these highly complex tumors. Since surgical resection continues to remain a mainstay of treatment, preventing and managing surgical complications, especially cerebellar mutism syndrome (CMS), is paramount. We describe the current theories for the etiology of CMS and two centers' experience in mitigating its risks. As our surgical toolbox continues to evolve along with our understanding of these tumors, we hope future patients can benefit from both improved overall survival and quality of life.

Integrated analysis of multiple methods reveals characteristics of the immune microenvironment in medulloblastoma

To explore the characteristics of the immune microenvironment (IME) of medulloblastoma (MB) by four methods: flow cytometry (FCM), immunohistochemical (IHC), bulk RNA expression and single cell RNA sequencing (scRNA-seq), we collected the intraoperative specimens of MB, ependymoma (EPN), high-grade glioma (HGG), and low-grade glioma (LGG) to make a cross-cancer comparison. The specimens were subjected to FCM and IHC respectively, and deconvolution from bulk RNA expression data and scRNA-seq analysis were performed in MB from the GEO database. FCM and IHC analysis found that the proportion of lymphocytes (LC) and T cells between MB and other brain tumors were significantly different. The deconvolution of bulk RNA expression data showed that only the proportion of cell types in MCPCOUNTER changed greatly. scRNA-seq found that the proportion of various immune cells in the IME of MB differed between different subtypes. Techniques such as FCM, IHC, bulk RNA expression, and scRNA-seq can sort out different immune cell subsets to a certain extent and quantify their proportions. The four methods have their own strengthens and limitations, but for highly heterogeneous tumor such as MB, integrated analysis of multiple methods is a better choice.

The Burden of Surviving Childhood Medulloblastoma: A Population-Based, Matched Cohort Study in Ontario, Canada

PURPOSE

Survivors of childhood medulloblastoma suffer from substantial late effects. We characterized these sequelae using real-world health services data in a population-based cohort of medulloblastoma survivors.

METHODS

All 5-year medulloblastoma survivors diagnosed age < 18 years between 1987 and 2015 in Ontario, Canada, were identified and matched 1:5 with population controls. Index date was 5 years from latest pediatric cancer event. Linkage to provincial administrative health data allowed for comparison of cumulative incidences of several adverse outcomes.

RESULTS

Two hundred thirty survivors, 81.3% of whom had received craniospinal irradiation, were matched with 1,150 controls. The 10-year postindex cumulative incidence of all-cause mortality was 7.9% (95% CI, 3.9 to 11.8) in survivors versus 0.6% (95% CI, 0.1 to 1.1) in controls (hazard ratio [HR], 21.5; 95% CI, 9.8 to 54.0). The cumulative incidence of stroke was higher in survivors (4.8%; 95% CI, 2.2 to 9.0) compared with controls (0.1; 95% CI, 0.01 to 0.7; HR, 45.6; 95% CI, 12.8 to 289.8). Hearing loss requiring an amplification device was present in 24.9% (95% CI, 18.8 to 31.4) of survivors versus 0.3% (95% CI, 0.1 to 1.0) of controls (HR, 96.3; 95% CI, 39.7 to 317.3). Disability support prescription claims were submitted by 44.5% (95% CI, 37.1 to 51.6) of survivors versus 5.5% (95% CI, 4.2 to 7.1) of controls (HR, 10.0; 95% CI, 7.3 to 13.6). Female survivors were significantly less likely to deliver a liveborn child compared with controls (HR, 0.2; 95% CI, 0.1 to 0.7).

CONCLUSION

Survivors of medulloblastoma have significant long-term medical sequelae, increased all-cause mortality, and are frequently dependent on disability supports. Efforts to reduce the toxicity of current therapy, specifically incorporating molecularly informed risk stratification to spare low- and intermediate-risk survivors the toxicity of treatment, are urgently needed. These findings should prompt a re-evaluation of our current treatment approaches where research focused on late-effect interventions should be prioritized.

Simultaneous Ultra-Sensitive Detection of Structural and Single Nucleotide Variants Using Multiplex Droplet Digital PCR in Liquid Biopsies from Children with Medulloblastoma

Medulloblastoma is a malignant embryonal tumor of the central nervous system (CNS) that mainly affects infants and children. Prognosis is highly variable, and molecular biomarkers for measurable residual disease (MRD) detection are lacking. Analysis of cell-free DNA (cfDNA) in cerebrospinal fluid (CSF) using broad genomic approaches, such as low-coverage whole-genome sequencing, has shown promising prognostic value. However, more sensitive methods are needed for MRD analysis. Here, we show the technical feasibility of capturing medulloblastoma-associated structural variants and point mutations simultaneously in cfDNA using multiplexed droplet digital PCR (ddPCR). Assay sensitivity was assessed with a dilution series of tumor in normal genomic DNA, and the limit of detection was below 100 pg of input DNA for all assays. False positive rates were zero for structural variant assays. Liquid biopsies (CSF and plasma, n = 47) were analyzed from 12 children with medulloblastoma, all with negative CSF cytology. MRD was detected in 75% (9/12) of patients overall. In CSF samples taken before or within 21 days of surgery, MRD was detected in 88% (7/8) of patients with localized disease and in one patient with the metastasized disease. Our results suggest that this approach could expand the utility of ddPCR and complement broader analyses of cfDNA for MRD detection.

Global survival trends for brain tumors, by histology: Analysis of individual records for 67,776 children diagnosed in 61 countries during 2000-2014 (CONCORD-3)

INTRODUCTION

Tumors of the central nervous system are among the leading causes of cancer-related death in children. Population-based cancer survival reflects the overall effectiveness of a health care system in managing cancer. Inequity in access to care world-wide may result in survival disparities.

METHODS

We considered children (0-14 years) diagnosed with a brain tumor during 2000-2014, regardless of tumor behavior. Data underwent a rigorous, three-phase quality control as part of CONCORD-3. We implemented a revised version of the International Classification of Childhood Cancer (third edition) to control for under-registration of non-malignant astrocytic tumors. We estimated net survival using the unbiased nonparametric Pohar Perme estimator.

RESULTS

The study included 67,776 children. We estimated survival for 12 histology groups, each based on relevant ICD-O-3 codes. Age-standardized 5-year net survival for low-grade astrocytoma ranged between 84% and 100% world-wide during 2000-2014. In most countries, 5-year survival was 90% or more during 2000-2004, 2005-2009, and 2010-2014. Global variation in survival for medulloblastoma was much wider, with age-standardized 5-year net survival between 47% and 86% for children diagnosed during 2010-2014.

CONCLUSIONS

To the best of our knowledge, this study provides the largest account to date of global trends in population-based survival for brain tumors in children, by histology. We devised an enhanced version of ICCC-3 to account for differences in cancer registration practices world-wide. Our findings may have public health implications, because low-grade glioma is 1 of the 6 index childhood cancers included by WHO in the Global Initiative for Childhood Cancer.

The Epidemiology of Brain and Spinal Cord Tumors

CNS tumors are a diverse group of neoplasms that emerge from a variety of different CNS cell types. These tumors may be benign, malignant, or borderline in nature. The majority of high grade glial tumors are fatal, with the exception of pilocytic astrocytoma. Primary malignant CNS tumors occur at a global annual rate of 2.1 to 5.8 per 100,000 persons. Males are more likely to develop malignant brain tumors than females, whereas benign meningiomas are more common in adult females. Additionally, gender inequalities in non-malignant tumors peak between the ages of 25 and 29 years. Only a small number of genetic variants have been associated with survival and prognosis. Notably, central nervous system (CNS) tumors exhibit significant age, gender, and race variation. Race is another factor that affects the incidence of brain and spinal cord tumors. Different races exhibit variation in terms of the prevalence of brain and CNS malignancies. This chapter discusses ongoing research on brain and spinal cord tumor epidemiology, as well as the associated risks and accompanied disorders.

Sex differences in methylation profiles are apparent in medulloblastoma, particularly among SHH tumors

Background

Medulloblastoma, the most common malignant pediatric brain tumor, displays marked sex differences in prevalence of the four main molecular subgroups: SHH, WNT, Group 3 and Group 4. Males are more frequently diagnosed with SHH, Group 3 and 4 tumors, which have worse prognoses than WNT tumors. Little is known about sex differences in methylation profiles within subgroups.

Methods

Using publicly available methylation data (Illumina HumanMethylation450K array), we compared beta values for males versus females. Differentially methylated positions (DMP) by sex within medulloblastoma subgroups were identified on the autosomes. DMPs were mapped to genes and Reactome pathway analysis was run by subgroup. Kaplan-Meier survival curves (Log-Rank p-values) were assessed for each sex within subgroup. MethylCIBERSORT was used to investigate the tumor microenvironment using deconvolution to estimate the abundances of immune cell types using DNA methylation data.

Results

There were statistically significant differences in sex by medulloblastoma subgroups (chi-squared p-value=0.00004): Group 3 (n=144; 65% male), Group 4 (n=326; 67% male), SHH (n=223; 57% male) and WNT (n=70; 41% male). Females had worse survival than males for SHH (p-value=0.02). DMPs by sex were identified within subgroups: SHH (n=131), Group 4 (n=29), Group 3 (n=19), and WNT (n=16) and validated in an independent dataset. Unsupervised hierarchical clustering showed that sex-DMPs in SHH did not correlate with other tumor attributes. Ten genes with sex DMPs (RFTN1, C1orf103, FKBP1B, COL25A1, NPDC1, B3GNT1, FOXN3, RNASEH2C, TLE1, and PHF17) were shared across subgroups. Significant pathways (p<0.05) associated with DMPs were identified for SHH (n=22) and Group 4 (n=4) and included signaling pathways for RET proto-oncogene, advanced glycosylation end product receptor, regulation of KIT, neurotrophic receptors, NOTCH, and TGF-β. In SHH, we identified DMPs in four genes (CDK6, COL25A1, MMP16, PRIM2) that encode proteins which are the target of therapies in clinical trials for other cancers. There were few sex differences in immune cell composition within tumor subgroups.

Conclusion

There are sexually dimorphic methylation profiles for SHH medulloblastoma where survival differences were observed. Sex-specific therapies in medulloblastoma may impact outcomes.

Nucleic acid therapy in pediatric cancer

The overall survival, progress free survival, and life quality of cancer patients have improved due to the advance in minimally invasive surgery, precision radiotherapy, and various combined chemotherapy in the last decade. Furthermore, the discovery of new types of therapeutics, such as immune checkpoint inhibitors and immune cell therapies have facilitated both patients and doctors to fight with cancers. Moreover, in the context of the development in biocompatible and cell type targeting nano-carriers as well as nucleic acid-based drugs for initiating and enhancing the anti-tumor response have come to the age. The treatment paradigms utilization of nucleic acids, including short interfering RNA (siRNA), antisense oligonucleotides (ASO), and messenger RNA (mRNA), can target specific protein expression to achieve the therapeutic effects. Over ten nucleic acid therapeutics have been approved by the FDA and EMA in rare diseases and genetic diseases as well as dozens of registered clinical trails for varies cancers. Though generally less dangerous of pediatric cancers than adult cancers was observed during the past decades, yet pediatric cancers accounted for a significant proportion of child deaths which hurt those family very deeply. Therefore, it is necessary to pay more attention for improving the treatment of pediatric cancer and discovering new nucleic acid therapeutics which may help to improve the therapeutic effect and prognoses in turns to ameliorate the survival period and quality of life for children patient. In this review, we focus on the nucleic acid therapy in pediatric cancers.

Aligning the Central Brain Tumor Registry of the United States (CBTRUS) histology groupings with current definitions

Background

The Central Brain Tumor Registry of the United States (CBTRUS) uses a histology grouping model based on the World Health Organization (WHO) classifications to group records for clinically relevant statistical reporting. Newly identified genetic markers more accurately stratify patients than histology alone and were incorporated into the 2016 update to the WHO Classification.

Methods

CBTRUS and consulting neuropathologists reviewed and aligned histology groupings with the 2016 WHO update. "Obsolete" (terms not currently in use) histology nomenclature along with their International Classification of Disease, Oncology 3rd edition (ICD-O-3) codes were identified, some histologies were reclassified to 2016 WHO, and new codes found in 2016 WHO were incorporated. An evaluation of the frequency of histology codes affected in the realignment process, and incidence and survival pre- and post-realignment was conducted.

Results

After review, 67 codes were noted as obsolete, 51 codes were reclassified, and 12 new codes were incorporated. Histology groups most affected were mesenchymal tumors and neuronal/mixed neuronal-glial tumors. Reorganization resulted in 2588 (0.65%) cases with grouping reassignment or reporting change, indicating that the 2016 WHO Classification revision has impacted the collection and reporting of primary brain and other CNS tumors.

Conclusion

This work demonstrates the need to be responsive to changes in classification and coding in order to ensure the most up-to-date and accurate statistics for brain and CNS tumors. This will require collaboration from all stakeholders within the brain tumor community, so to have the ability to reconcile clinical practices and surveillance requirements.

The role of m6A modification in pediatric cancer

With the development of RNA modification research, the importance of N6-methyladenosine (m6A) in tumors cannot be ignored. m6A promotes the self-renewal of tumor stem cells and the proliferation of tumor cells. It affects post-transcriptional gene expression through epigenetic mechanisms, combining various factors to determine proteins' fate and altering the biological function. This modification process runs through the entire tumors, and genes affected by m6A modification may be the critical targets for cancers breakthroughs. Though generally less dangerous than adult cancer, pediatric cancer accounts for a significant proportion of child deaths. What is more alarming is that the occurrences of adult tumors are highly associated with the poor prognoses of pediatric tumors. Therefore, it is necessary to pay attention to the importance of pediatric cancer and discover new therapeutic targets, which will help improve the therapeutic effect and prognoses of the diseases. We collected and investigated m6A modification in pediatric cancers based on mRNA and non-coding RNA, finding that m6A factors were involved in glioma, hepatoblastoma, nephroblastoma, neuroblastoma, osteosarcoma, medulloblastoma, retinoblastoma, and acute lymphoblastic leukemia. Consequently, we summarized the relationships between the m6A factors and these pediatric cancers.

Racial/ethnic and sex differences in young adult malignant brain tumor incidence by histologic type

BACKGROUND

Brain tumors are among the top four cancers in young adults. We assessed important windows of tumor development and examined the interplay of race/ethnicity, age, and sex in young adult brain tumor incidence.

METHODS

Using SEER 18 data (2000-2017), incidence rates were estimated by Poisson regression in individuals aged 20-39 years at diagnosis. Incidence rate ratios (IRR) and 95% confidence intervals (95% CI) were estimated by race/ethnicity, sex and age for 12 malignant histologies.

RESULTS

White incidence for all histologies was higher (White vs. Black IRR: 2.09, 95% CI: 1.94, 2.24; White vs Asian Pacific Islander IRR: 1.88, 95% CI: 1.75, 2.03; White vs Hispanic IRR: 1.70, 95% CI: 1.62, 1.78; White vs American Indian IRR: 1.40, 95% CI: 1.14, 1.73). Minority groups had higher lymphoma incidence (White vs Black IRR: 0.32, 95% CI: 0.25, 0.40, White vs Hispanic HR: 0.55, 95% CI: 0.44, 0.68). Males had higher incidence than females for all histologies (IRR: 1.36, 95% CI: 1.31, 1.41). Male rates were highest for lymphoma (male-to-female [MF] IRR: 2.00, 95% CI: 1.65, 2.42) and glioblastoma (MF IRR: 1.61, 95% CI: 1.48, 1.75). The male excess in incidence was similar by race/ethnicity and increased with age (20-24-year-old IRR: 1.18, 95% CI: 1.07, 1.29; 35-39-year-old IRR: 1.44, 95% CI: 1.35, 1.54).

CONCLUSIONS

A White race and male incidence excess was observed among brain tumors.

IMPACT

The male excess was similar by race/ethnicity and increased with age suggesting male sex may be an intrinsic risk factor for brain tumor development.

Bcl-XL but Not Bcl-2 Is a Potential Target in Medulloblastoma Therapy

Medulloblastoma (MB) is the most common solid tumour in children and, despite current treatment with a rather aggressive combination therapy, accounts for 10% of all deaths associated with paediatric cancer. Breaking the tumour cells’ intrinsic resistance to therapy-induced cell death should lead to less aggressive and more effective treatment options. In other tumour entities, this has been achieved by modulating the balance between the various pro- and anti-apoptotic members of the Bcl-2 family with small molecule inhibitors. To evaluate the therapeutic benefits of ABT-199 (Venetoclax), a Bcl-2 inhibitor, and ABT-263 (Navitoclax), a dual Bcl-XL/Bcl-2 inhibitor, increasingly more relevant model systems were investigated. Starting from established MB cell lines, progressing to primary patient-derived material and finally an experimental tumour system imbedded in an organic environment were chosen. Assessment of the metabolic activity (a surrogate readout for population viability), the induction of DNA fragmentation (apoptosis) and changes in cell number (the combined effect of alterations in proliferation and cell death induction) revealed that ABT-263, but not ABT-199, is a promising candidate for combination therapy, synergizing with cell death-inducing stimuli. Interestingly, in the experimental tumour setting, the sensitizing effect of ABT-263 seems to be predominantly mediated via an anti-proliferative and not a pro-apoptotic effect, opening a future line of investigation. Our data show that modulation of specific members of the Bcl-2 family might be a promising therapeutic addition for the treatment of MB.

The Alliance AMBUSH Trial: Rationale and Design

Simple Summary

Medulloblastoma, the most common embryonal tumor in children, can also arise in older patients. Clinical studies in children with medulloblastoma have increased our understanding of molecular pathways and improved treatment strategies. We now know that medulloblastoma has at least four subtypes and each maybe best suited to specific therapies. The sonic hedgehog (SHH) pathway is altered in a significant proportion of older patients with medulloblastoma. The Alliance for Clinical Trials in Oncology cooperative group is developing the AMBUSH trial: Comprehensive Management of Adolescent and Young Adult (AYA) and Adult Patients with Medulloblastoma or Pineal Embryonal Tumors With A Randomized Placebo Controlled Phase II Focusing on Sonic Hedgehog Pathway Inhibition in SHH Subgroup Patients (Adult & Adolescent MedulloBlastoma Using Sonic Hedgehog Trial). The trial gives treatment directions for all patients and randomizes patients with average risk SHH-activated medulloblastoma to maintenance sonidegib, a hedgehog signaling pathway inhibitor, or placebo. This trial will establish a baseline for future trial comparison and investigate the benefit of a novel targeted agent.

Abstract

Unlike medulloblastoma (MB) in children, robust prospective trials have not taken place for older patients due to the low incidence of MB in adults and adolescent and young adults (AYA). Current MB treatment paradigms for older patients have been extrapolated from the pediatric experience even though questions exist about the applicability of these approaches. Clinical and molecular classification of MB now provides better prognostication and is being incorporated in pediatric therapeutic trials. It has been established that genomic alterations leading to activation of the sonic hedgehog (SHH) pathway occur in approximately 60% of MB in patients over the age of 16 years. Within this cohort, protein patched homolog (PTCH) and smoothened (SMO) mutations are commonly found. Among patients whose tumors harbor the SHH molecular signature, it is estimated that over 80% of patients could respond to SHH pathway inhibitors. Given the advances in the understanding of molecular subgroups and the lack of robust clinical data for adult/AYA MB, the Alliance for Clinical Trial in Oncology group developed the AMBUSH trial: Comprehensive Management of AYA and Adult Patients with Medulloblastoma or Pineal Embryonal Tumors with a Randomized Placebo Controlled Phase II Focusing on Sonic Hedgehog Pathway Inhibition in SHH Subgroup Patients (Adult & Adolescent MedulloBlastoma Using Sonic Hedgehog Trial). This trial will enroll patients 18 years of age or older with MB (any molecular subgroup and risk stratification) or pineal embryonal tumor. Patients will be assigned to one of three cohorts: (1) average risk non-SHH-MB, (2) average risk SHH-MB, and (3) high risk MB or pineal embryonal tumors. All patients will receive protocol-directed comprehensive treatment with radiation therapy and chemotherapy. Patients with SHH-MB in cohort 1 will be randomized to a smoothened inhibitor or placebo as maintenance therapy for one year.

Protocols to Manufacture an Oncolytic Measles Virus-Sensitive Immunocompetent Mouse Model of Medulloblastoma

Oncolytic virotherapy translational research in the current era is heavily focused on the interaction of the immune system and tumor microenvironment with oncolytic viruses. Preclinical xenograft studies using human cells in immunodeficient mouse models does not serve this purpose. As a consequence, developing syngeneic immunocompetent murine cancer models sensitive to infection and growth of specific oncolytic viruses is required. The group 3 subtype of medulloblastoma, among the four molecular subgroups-WNT, SHH, Group 3, and Group 4, has the worst prognosis and the poorest outcome. Sadly, current treatments cause long-term toxicity and morbidity to survivors adversely affecting their quality of life. Alternate effective therapy with less side effects is urgently needed. We have shown that oncolytic measles virus (MV) is effective against localized as well as CSF-disseminated medulloblastoma in immunodeficient mouse models. To study the interaction of immune system with oncolytic measles virotherapy, we have developed a murine group 3 medulloblastoma cell line (CSCG) that is infectible by MV, is killed by MV, allows replication of MV, and is tumorigenic in the brain of syngeneic transgenic immune-competent mice. Intratumoral injection of MV results in significant prolongation of survival in mice bearing CSCG tumors in the brain. This model provides the first suitable platform to examine therapeutic regimens of MV therapy for MB tumors in the presence of intact immune system. Here, we describe our lab protocols to develop this cell line and the mouse model.

Magnetic Resonance Imaging in the Contemporary Management of Medulloblastoma: Current and Emerging Applications

Medulloblastoma, the most common malignant primary brain tumor in children, is now considered to comprise of four distinct molecular subgroups-wingless (WNT), sonic hedgehog (SHH), Group 3, and Group 4 medulloblastoma, each associated with distinct developmental origins, unique transcriptional profiles, diverse phenotypes, and variable clinical behavior. Due to its exquisite anatomic resolution, multiparametric nature, and ability to image the entire craniospinal axis, magnetic resonance imaging (MRI) is the preferred and recommended first-line imaging modality for suspected brain tumors including medulloblastoma. Preoperative MRI can reliably differentiate medulloblastoma from other common childhood posterior fossa masses such as ependymoma, pilocytic astrocytoma, and brainstem glioma. On T1-weighted images, medulloblastoma is generally iso- to hypointense, while on T2-weighted images, the densely packed cellular component of the tumor is significantly hypointense and displays restricted diffusion on diffusion-weighted imaging. Following intravenous gadolinium, medulloblastoma shows significant but variable and heterogeneous contrast enhancement. Given the propensity of neuraxial spread in medulloblastoma, sagittal fat-suppressed T1-postcontrast spinal MRI is recommended to rule out leptomeningeal metastases for accurate staging. Following neurosurgical excision, postoperative MRI done within 24-48 h confirms the extent of resection, accurately quantifying residual tumor burden imperative for risk assignment. Post-treatment MRI is needed to assess response and effectiveness of adjuvant radiotherapy and systemic chemotherapy. After completion of planned therapy, surveillance MRI is recommended periodically on follow-up for early detection of recurrence for timely institution of salvage therapy, as well as for monitoring treatment-related late complications. Recent studies suggest that preoperative MRI can reliably identify SHH and Group 4 medulloblastoma but has suboptimal predictive accuracy for WNT and Group 3 tumors. In this review, we focus on the role of MRI in the diagnosis, staging, and quantifying residual disease; post-treatment response assessment; and periodic surveillance, and provide a brief summary on radiogenomics in the contemporary management of medulloblastoma.

Epidemiology of brain tumors among adolescents and young adults in Nigeria

Adolescents and Young Adults (AYA), have distinct endocrine and psychosocial peculiarities. Brain tumors occur less among AYAs, compared to other age groups and with better prognosis. There is however a paucity of literature about brain tumors in AYA in sub-Saharan Africa. We aim to describe the clinical characteristics of brain tumors in AYA across five neurosurgical centers in Nigeria and the associated factors. We report results for older children (10-14 years), adolescents (15-19 years) and young adults (20-24 years). This was a retrospective review of AYA with brain tumors over a 10-year period (2010-2019). Data analysis was by descriptive statistics, Chi square test and multinomial regression at α0.05. There were 104 AYAand the male to female ratio was 1.2:1. Headache (79.8%) and visual symptoms (65.4%) were the most common presenting symptoms. Focal limb weakness (44.1%) occurred less frequently. Median duration of symptoms prior to presentation was 9 months. Glioma was the most common tumor (31, 29.8%) while pituitary adenoma and craniopharyngioma constituted 30.8% of the tumors. Patients with symptom duration of ≤one year were more likely to have infratentorial tumors. There was no significant association between the KPS following intervention and the AYA characteristics. Age group was not significantly associated with any of the presenting symptoms except ataxia, which was significantly higher among the 10 to 14 years group.We have described the epidemiology of brain tumors within AYA in Nigeria and highlighted a need to maximize their care and meet their special needs.

Identification of Let-7 miRNA Activity as a Prognostic Biomarker of SHH Medulloblastoma

Medulloblastoma (MB) is the most common pediatric embryonal brain tumor. The current consensus classifies MB into four molecular subgroups: sonic hedgehog-activated (SHH), wingless-activated (WNT), Group 3, and Group 4. MYCN and let-7 play a critical role in MB. Thus, we inferred the activity of miRNAs in MB by using the ActMiR procedure. SHH-MB has higher MYCN expression than the other subgroups. We showed that high MYCN expression with high let-7 activity is significantly associated with worse overall survival, and this association was validated in an independent MB dataset. Altogether, our results suggest that let-7 activity and MYCN can further categorize heterogeneous SHH tumors into more and less-favorable prognostic subtypes, which provide critical information for personalizing treatment options for SHH-MB. Comparing the expression differences between the two SHH-MB prognostic subtypes with compound perturbation profiles, we identified FGFR inhibitors as one potential treatment option for SHH-MB patients with the less-favorable prognostic subtype.

ONC201/TIC10 Is Empowered by 2-Deoxyglucose and Causes Metabolic Reprogramming in Medulloblastoma Cells in Vitro Independent of C-Myc Expression

The purpose of this study was to examine whether the imipridone ONC201/TIC10 affects the metabolic and proliferative activity of medulloblastoma cells in vitro. Preclinical drug testing including extracellular flux analyses (agilent seahorse), MTT assays and Western blot analyses were performed in high and low c-myc-expressing medulloblastoma cells. Our data show that treatment with the imipridone ONC201/TIC10 leads to a significant inihibitory effect on the cellular viability of different medulloblastoma cells independent of c-myc expression. This effect is enhanced by glucose starvation. While ONC201/TIC10 decreases the oxidative consumption rates in D458 (c-myc high) and DAOY (c-myc low) cells extracellular acidification rates experienced an increase in D458 and a decrease in DAOY cells. Combined treatment with ONC201/TIC10 and the glycolysis inhibitor 2-Deoxyglucose led to a synergistic inhibitory effect on the cellular viability of medulloblastoma cells including spheroid models. In conclusion, our data suggest that ONC201/TIC10 has a profound anti-proliferative activity against medulloblastoma cells independent of c-myc expression. Metabolic targeting of medulloblastoma cells by ONC201/TIC10 can be significantly enhanced by an additional treatment with the glycolysis inhibitor 2-Deoxyglucose. Further investigations are warranted.

Childhood Malignant Brain Tumors: Balancing the Bench and Bedside

Simple Summary

Brain tumors remain the most common childhood solid tumors, accounting for approximately 25% of all pediatric cancers. They also represent the most common cause of cancer-related illness and death in this age group. Recent years have witnessed an evolution in our understanding of the biological underpinnings of many childhood brain tumors, potentially improving survival through both improved risk group allocation for patients to provide appropriate treatment intensity, and novel therapeutic breakthroughs. This review aims to summarize the molecular landscape, current trial-based standards of care, novel treatments being explored and future challenges for the three most common childhood malignant brain tumors—medulloblastomas, high-grade gliomas and ependymomas.

Abstract

Brain tumors are the leading cause of childhood cancer deaths in developed countries. They also represent the most common solid tumor in this age group, accounting for approximately one-quarter of all pediatric cancers. Developments in neuro-imaging, neurosurgical techniques, adjuvant therapy and supportive care have improved survival rates for certain tumors, allowing a future focus on optimizing cure, whilst minimizing long-term adverse effects. Recent times have witnessed a rapid evolution in the molecular characterization of several of the common pediatric brain tumors, allowing unique clinical and biological patient subgroups to be identified. However, a resulting paradigm shift in both translational therapy and subsequent survival for many of these tumors remains elusive, while recurrence remains a great clinical challenge. This review will provide an insight into the key molecular developments and global co-operative trial results for the most common malignant pediatric brain tumors (medulloblastoma, high-grade gliomas and ependymoma), highlighting potential future directions for management, including novel therapeutic options, and critical challenges that remain unsolved.

[ARTICLE WITHDRAWN] MicroRNA-362-3p Inhibits Glioma Growth by Targeting PAX3 and Regulating Wnt/Beta-Catenin Pathway

THIS ARTICLE WAS WITHDRAWN BY THE PUBLISHER IN October 2021

Malignant idiopathic intracranial hypertension revealed a hidden primary spinal leptomeningeal medulloblastoma

Frequently the cause of raised intracranial pressure remains unresolved and rarely is related to spinal tumours, moreover less to spinal medulloblastoma without primary brain focus. An 18-year-old woman had a 3-month history of headache and impaired vision. Neurological examination revealed bilateral sixth cranial nerve palsies with bilateral papilloedema of grade III. No focal brain or spine lesion was found on imaging. Consecutive lumbar punctures showed high opening pressure and subsequent increasing protein level. Meningeal biopsy was negative. At one point, she developed an increasing headache, vomiting and back pain. Spine MRI showed diffuse nodular leptomeningeal enhancement with the largest nodule at T6-T7. Malignant cells were detected in cerebrospinal fluid. She underwent laminectomy with excisional biopsy, and pathology showed medulloblastoma WHO grade IV. She was treated with chemotherapy and craniospinal irradiation and made a good recovery.

Pediatric brain tumors: the era of molecular diagnostics, targeted and immune-based therapeutics, and a focus on long term neurologic sequelae

Pediatric brain tumors are the second most common malignancy of childhood after acute leukemia and the number one cause of cancer-related mortality¹. Over the past decade, advanced molecular diagnostics have led to the discovery of new molecularly-defined tumor types with prognostic and therapeutic implications. Methylation profiles, whole genome sequencing, and transcriptomics have defined subgroups and revealed heterogeneity within commonly defined tumor entities^2,3. These findings have also revealed important differences between adult and pediatric brain tumors of similar histology. The majority of pediatric low grade gliomas (pLGG) are defined by alterations in the mitogen-activated protein kinase (MAPK) pathway including BRAFV600E point mutation, K1AA1549-BRAF fusion, and FGFR1 alterations as opposed to IDH1/2 mutations and 1p/19q co-deletion seen more frequently in adult low grade gliomas⁴. These findings have led to targeted therapies, namely BRAF and MEK inhibitors, which are currently being evaluated in phase III clinical trials and may soon supplant chemotherapy as standard of care for pLGG's. While targeted therapy trials for pediatric brain tumors have had significant success, immunotherapy remains a challenge in a group of tumors with generally lower mutational burden compared to adult tumors and relatively "cold" immune microenvironment. Despite this, a wide array of immunotherapy trials including vaccine therapies, immune checkpoint blockade, chimeric antigen receptor (CAR) T cells, and viral therapies are on-going. Unique to pediatrics, multiple clinical trials have sought to answer the question of whether the most malignant pediatric brain tumors in the youngest patients can be successfully treated with high dose chemotherapy in lieu of radiation to avoid devastating long-term neurocognitive deficits. Due to the collaborative work of multiple pediatric neuro-oncology consortiums, the recent history of pediatric brain tumor research is one of efficient translation from bench to bedside in a rare group of tumors resulting in significant progress in the field. Here, advances in the areas of molecular characterization, targeted and immune-based therapies, and reduction in long term co-morbidities will be reviewed.

Radiation therapy for infants with cancer

The clinical outcomes for infants with malignant tumors are often worse than older children due to a combination of more biologically aggressive disease in some cases, and increased toxicity-or deintensification of therapies due to concern for toxicity-in others. Especially in infants and very young children, finding the appropriate balance between maximizing treatment efficacy while minimizing toxicity-in particular late side effects-is crucial. We review here the management of malignant tumors in infants and very young children, focusing on central nervous system (CNS) malignancies and rhabdomyosarcoma.

Epigenomics and immunotherapeutic advances in pediatric brain tumors

Brain tumors are the leading cause of childhood cancer-related deaths. Similar to adult brain tumors, pediatric brain tumors are classified based on histopathological evaluations. However, pediatric brain tumors are often histologically inconsistent with adult brain tumors. Recent research findings from molecular genetic analyses have revealed molecular and genetic changes in pediatric tumors that are necessary for appropriate classification to avoid misdiagnosis, the development of treatment modalities, and the clinical management of tumors. As many of the molecular-based therapies developed from clinical trials on adults are not always effective against pediatric brain tumors, recent advances have improved our understanding of the molecular profiles of pediatric brain tumors and have led to novel epigenetic and immunotherapeutic treatment approaches currently being evaluated in clinical trials. In this review, we focus on primary malignant brain tumors in children and genetic, epigenetic, and molecular characteristics that differentiate them from brain tumors in adults. The comparison of pediatric and adult brain tumors highlights the need for treatments designed specifically for pediatric brain tumors. We also discuss the advancements in novel molecularly targeted drugs and how they are being integrated with standard therapy to improve the classification and outcomes of pediatric brain tumors in the future.

Advances in Understanding the LncRNA-Mediated Regulation of the Hippo Pathway in Cancer

Long noncoding RNAs (lncRNAs) are a class of RNA molecules that are longer than 200 nucleotides and cannot encode proteins. Over the past decade, lncRNAs have been defined as regulatory elements of multiple biological processes, and their aberrant expression contributes to the development and progression of various malignancies. Recent studies have shown that lncRNAs are involved in key cancer-related signaling pathways, including the Hippo signaling pathway, which plays a prominent role in controlling organ size and tissue homeostasis by regulating cell proliferation, apoptosis, and differentiation. However, dysregulation of this pathway is associated with pathological conditions, especially cancer. Accumulating evidence has revealed that lncRNAs can modulate the Hippo signaling pathway in cancer. In this review, we elaborate on the role of the Hippo signaling pathway and the advances in the understanding of its lncRNA-mediated regulation in cancer. This review provides additional insight into carcinogenesis and will be of great clinical value for developing novel early detection and treatment strategies for this deadly disease.

Racial and ethnic disparities in survival of children with brain and central nervous tumors in the United States

BACKGROUND

Despite improvements in overall survival for pediatric cancers, treatment disparities remain for racial/ethnic minorities compared to non-Hispanic Whites; however, the impact of race on treatment outcomes for pediatric brain and central nervous system (CNS) tumors in the United States is not well known.

METHODS

We included 8713 children aged 0-19 years with newly diagnosed primary brain and CNS tumors between 2000 and 2015 from the Census Tract-level SES and Rurality Database developed by Surveillance, Epidemiology, and End Results (SEER) Program. We used chi-square tests to assess differences in sociodemographic, cancer, and treatment characteristics by race/ethnicity and Kaplan-Meier curves and Cox proportional hazards models to examine differences in 10-year survival, adjusting for these characteristics.

RESULTS

Among 8713 patients, 56.75% were non-Hispanic White, 9.59% non-Hispanic Black, 25.46% Hispanic, and 8.19% from "other" racial/ethnic groups. Median unadjusted survival for all pediatric brain tumors was 53 months, but varied significantly by race/ethnicity with a median survival of 62 months for non-Hispanic Whites, 41 months for non-Hispanic Blacks, and 40 months for Hispanic and other. Multivariable analyses demonstrated minority racial groups still had significantly higher hazard of death than non-Hispanic Whites; Hispanic (adjusted hazard ratio [aHR] 1.25 [1.18-1.31]); non-Hispanic Black (aHR 1.12 [1.04-1.21]); other (aHR 1.22 [1.12-1.32]). Results were consistent when stratified by tumor histology.

CONCLUSION

We identified disparities in survival among racial/ethnic minorities with pediatric brain and CNS tumors, with Hispanic patients having the highest risk of mortality. Eliminating these disparities requires commitment toward promoting heath equity and personalized cancer treatment.

Real-world data for pediatric medulloblastoma: can we improve outcomes?

Medulloblastoma (MB) is a malignant embryonal tumor that develops especially in childhood, with overall survival (OS) at 5 years of up to 70%. The objective of this study is to analyze treatment delivery variables in a retrospective cohort and evaluate the impact of these treatment quality parameters on survival. From 2000 to 2018, 40 pediatric patients with medulloblastoma, treated according to current international protocols, were retrospectively analyzed. Treatment delivery quality indicators were analyzed including the extent of surgery, radiotherapy (RT) parameters, and chemotherapy variables, related with time and dose-intensity deviations. With a median follow-up of 74 months (range, 6-195), OS at 5 years was 74 ± 7%, 81 ± 8% for standard-risk, and 55 ± 16% for high-risk patients (p = 0.090). Disease-free survival at 5 years was not significantly affected by extent of surgery (p = 0.428) and RT-related variables such as surgery-RT interval (p = 0.776) neither RT duration (p = 0.172) or maintenance chemotherapy compliance (p = 0.634). Multivariate analysis identified risk groups predictive of worse DFS (p = 0.032) and leptomeningeal dissemination associated with inferior OS (p = 0.029).Conclusion: Treatment delivery optimization has improved survival rates of patients with MB. Despite this, in our study, we have not established a clear influence of the considered radiotherapy and chemotherapy treatment quality parameters on outcomes. What is Known: • Improvement in treatment modalities during the last decades has reached a 5-year OS of up to 70% in these patients. • Extent of resection and radiotherapy parameters such as interval between surgery-radiotherapy and radiotherapy duration has been described as probable survival prognostic factors. What is New: • Differences in medulloblastoma survival rates between prospective studies and retrospective series. • The impact on survival of the three main treatment variables, surgery, radiotherapy and chemotherapy, susceptible to improvement.

External Validation of a Nomogram and Risk Grouping System for Predicting Individual Prognosis of Patients With Medulloblastoma

Background: Medulloblastoma (MB) is one of the most malignant neuroepithelial tumors in the central nervous system. This study aimed to establish an effective prognostic nomogram and risk grouping system for predicting overall survival (OS) of patients with MB.

Materials and Methods: The nomogram was constructed based on data from the database of Surveillance, Epidemiology, and End Results (SEER). This database consisted of 2,824 patients with medulloblastoma and was used as the training cohort. The data of another additional 161 patients treated at the Sun Yat-sen University Cancer Center (SYSUCC) were used as the external validation cohort. Cox regression analysis was used to select independent prognostic factors. Concordance index (C-index) and calibration curve were used to predict the prognostic effect of the nomogram for overall survival.

Results: In the training cohort, Cox regression analyses showed that the prognostic factors included histopathology, surgery, radiotherapy, chemotherapy, tumor size, dissemination, and age at diagnosis. The internal and external validated C-indexes were 0.681 and 0.644, respectively. Calibration curves showed that the nomogram was able to predict 1-, 3-, and 5-year OS for patients with MB precisely. Using the training cohort, a risk grouping system was built, which could perfectly classify patients into four risk nomogroups with a 5-year survival rate of 83.9%, 76.5%, 64.5%, and 46.8%, respectively.

Conclusion: We built and validated a nomogram and risk grouping system that can provide individual prediction of OS and distinguish MB patients from different risk groups. This nomogram and risk grouping system could help clinicians making better treatment plan and prognostic assessment.

Race, ethnicity, and socioeconomic differences in incidence of pediatric embryonal tumors in the United States

BACKGROUND

The etiology of childhood cancers and its social patterning remains largely unknown. Accounting for socioeconomic status (SES) when exploring the association between race/ethnicity and cancer incidence is necessary to better understand such etiology. We aimed to investigate differences in the incidence of embryonal tumors (ETs) by SES and race/ethnicity in the United States using population-based registries of the Surveillance, Epidemiology, and End Results (SEER) Program.

PROCEDURE

Children with ETs aged 0-19 years diagnosed between 2000 and 2015 were ascertained from the census tract-level SEER database. SES was measured using a tract-level composite index. Incidence rate ratios (IRRs) with 95% confidence intervals (CIs) by SES quintile and race/ethnicity were estimated using multivariable Poisson regression models.

RESULTS

The majority of tumors had lower incidence among nonwhite children compared with non-Hispanic (NH) white children, after controlling for SES. NH blacks had a higher incidence of Wilms tumor than NH whites (IRR: 1.26; 95% CI, 1.13-1.39). There was an increasing linear trend (P = 0.0001) across increasing SES quintile for embryonal rhabdomyosarcoma after controlling for race/ethnicity. Effect modification by race/ethnicity of the relationship between SES and tumor incidence was observed for several groups. Hispanics had a significant, linear trend (P = 0.0005) in the incidence of Wilms tumor, while Asian/Pacific Islanders experienced a significant inverse trend (P = 0.0002).

CONCLUSIONS

Results from this study suggest differences in the incidence of several ETs by race/ethnicity and that these differences may be modified by SES. Investigation of potential risk factors that are socially patterned is warranted.

Treatment and Outcomes for Central Nervous System Tumors in Australian Adolescents and Young Adults: A Population-Based National Study

Purpose: While central nervous system (CNS) tumors account for only 10% of adolescent and young adult (AYA) cancers, they are the leading cause of cancer death in this age group. Using national data for Australia, we describe the presentation, treatment, and survival for AYAs diagnosed with CNS tumors. Methods: A population-based study of 15-24 year-olds diagnosed with CNS tumors (low- and high-grade glioma [LGG, HGG], medulloblastoma [MB], primitive neuroectodermal tumors [PNET], ependymoma [EP]) or other (e.g., low-grade neuronal tumor) between 2007 and 2012. Clinical details were extracted from hospital medical records for each patient. Treatment centers were classified as pediatric or adult services. Results: Two hundred seventy-five patients (129 LGG, 77 HGG, 23 MB, 10 PNET, 19 EP, 17 other) were identified, with 17% treated at pediatric hospitals. Symptoms (headache [53%], nausea [31%]) were present for a median of 3 weeks before consulting a health professional. Of LGG patients, 15% had radiotherapy (RT) and 12% chemotherapy (CT). Of HGG patients, 81% had RT and 75% CT. All MB and PNET were managed with surgery, and 74% of MB and 80% of PNET had both RT and CT. Treatment did not differ by treatment center type. Five-year survival for LGG and EP was over 80%, but was 42% for HGG and 20% for PNET. Conclusions: This national, population-based study indicates similar treatment for AYA patients with CNS tumors between pediatric and adult services. Poor outcomes for HGG and PNET patients highlight the need for clinical trials of novel approaches for these tumors.

CNS Penetration of Cyclophosphamide and Metabolites in Mice Bearing Group 3 Medulloblastoma and Non-Tumor Bearing Mice

PURPOSE

Cyclophosphamide is widely used to treat children with medulloblastoma; however, little is known about its brain penetration. We performed cerebral microdialysis to characterize the brain penetration of cyclophosphamide (130 mg/kg, IP) and its metabolites [4-hydroxy-cyclophosphamide (4OH-CTX) and carboxyethylphosphoramide mustard (CEPM)] in non-tumor bearing mice and mice bearing orthotopic Group 3 medulloblastoma.

METHODS

A plasma pharmacokinetic study was performed in non-tumor-bearing CD1- nude mice, and four cerebral microdialysis studies were performed in non-tumor-bearing (M1 and M3) and tumor- bearing mice (M2 and M4). Plasma samples were collected up to 6-hours post-dose, and extracellular fluid (ECF) samples were collected over 60-minute intervals for 24-hours post-dose. To stabilize and quantify 4OH-CTX, a derivatizing solution was added in blood after collection, and either directly in the microdialysis perfusate (M1 and M2) or in ECF collection tubes (M3 and M4). Plasma/ECF cyclophosphamide and CEPM, and 4OH-CTX concentrations were separately measured using different LC-MS/MS methods.

RESULTS

All plasma/ECF concentrations were described using a population-based pharmacokinetic model. Plasma exposures of cyclophosphamide, 4OH-CTX, and CEPM were similar across studies (mean AUC=112.6, 45.6, and 80.8 µmol∙hr/L). Hemorrhage was observed in brain tissue when the derivatizing solution was in perfusate compared with none when in collection tubes, which suggested potential sample contamination in studies M1 and M2. Model-derived unbound ECF to plasma partition coefficients (Kp,uu) were calculated to reflect CNS penetration of the compounds. Lower cyclophosphamide Kp,uu was obtained in tumor-bearing mice versus non-tumor bearing mice (mean 0.15 versus 0.22, p=0.019). No differences in Kp,uu were observed between these groups for 4OH- CTX and CEPM (overall mean 0.10 and 0.07).

CONCLUSIONS

Future studies will explore potential mechanisms at the brain-tumor barrier to explain lower cyclophosphamide brain penetration in tumor-bearing mice. These results will be used to further investigate exposure-response relationships in medulloblastoma xenograft models.

Effects of proactive and rescue enteral tube feedings on weight change in children undergoing treatment for high-grade CNS tumors

Background

Children with high-grade CNS cancers frequently experience malnutrition during treatment. We assessed the effects of proactive enteral tube (ET) placement/enteral tube feedings (ETF) on weight in infants/children with high-grade CNS tumors treated with aggressive chemotherapy.

Methods

We conducted a retrospective study of patients age 0 to 19 years treated for new high-grade CNS tumors between 2002 and 2017 at a tertiary pediatric hospital system. Patients underwent placement of proactive ET (≤ 31 days postdiagnosis; n = 45), rescue ET (> 31 days, due to weight loss; n = 9), or no ET (n = 18). Most received surgically placed ET (98%), with percutaneous endoscopic gastrojejunostomy or gastrojejunostomy tubes favored to allow jejunal feeding. The majority of patients with ET used ETF (91%). Using mixed-effects regression models, we examined differences in mean weights between ET/ETF groups across the first year of treatment. We also evaluated observed weight changes.

Results

All infants (n = 22, median age, 1.5 years) had proactive ET placed and 21 of 22 used proactive ETF. Infants showed an initial increase in mean percentage weight change that eventually leveled off, for an estimated increase of 10.4% over the year. For the pediatric cohort (n = 50, median, 8.1 years), those receiving proactive ETF experienced weight increases (+9.9%), those with rescue ETF experienced an initial decline and eventually rebounded for no net change (0.0%), and those with no ETF demonstrated an initial decline that persisted (-11.9%; P _interaction < .001). Analysis of observed weights revealed nearly identical patterns.

Conclusions

Proactive ETF was effective at maintaining weight and/or facilitating weight gain over the first year of treatment and was acceptable to patients/families.

Medulloblastoma: an Old Diagnosis with New Promises

PURPOSE OF REVIEW

Molecular subtyping in medulloblastoma (MB) has diagnostic and prognostic values which impact therapy. This paper provides guidance for the clinician caring for pediatric and adult patients with medulloblastoma in the modern era.

RECENT FINDINGS

Medulloblastoma comprises four molecularly distinct subgroups: wingless activated (WNT), sonic hedgehog activated (SHH), group 3, and group 4. Risk stratification before and after the discovery of molecular subgroups aims at minimizing toxicity by reducing radiation and chemotherapy doses in low-risk patients while maintaining favorable overall survival (OS). The mainstay of newly diagnosed medulloblastoma treatment is surgery, radiation therapy, and chemotherapy, except for children under 6 years of age, where high-dose chemotherapy with autologous stem cell rescue is used to avoid or delay radiotherapy, preventing neurocognitive sequelae. Management of recurrent/refractory medulloblastoma remains a challenge with immunotherapy and small-molecule inhibitors forming the backbone of novel strategies. Recent innovations in medulloblastoma research allow us to better understand pathogenesis and molecular characteristics resulting in advanced risk stratification models, new therapeutic approaches, and overall improved survival and quality of life.

A Retrospective Analysis of the Demographics, Treatment, and Survival Outcomes of Patients with Desmoplastic Nodular Medulloblastoma Using the Surveillance, Epidemiology, and End Results (SEER) Database

Objective

Medulloblastoma is the most common malignant brain tumor in children younger than four years of age. Children diagnosed with desmoplastic nodular medulloblastoma (DNMB) have more favorable survival outcomes when compared to other subtypes of this disease and, to date, the demographics of DNMB have only been characterized by a few small clinical case series. Additionally, the current effort is being made at reducing radiotherapeutic modalities in this patient population to avoid the adverse effects associated with radiotherapy in children. Therefore, the goal of this study was to characterize the demographics, treatments, and survival outcomes of patients with DNMB using a large federal database.

Methods

The Surveillance, Epidemiology, and End Results database was queried to retrieve demographical, treatment, and survival data for patients diagnosed with DNMB. Statistical testing was performed with the R software stats package (R Foundation for Statistical Computing, Vienna, Austria). Student’s t tests and analysis of variance tests were used to measure differences among survival rates.

Results

Data from 360 patients with DNMB were retrieved from 1975-2016. There was a higher prevalence of DNMB in children younger than four years of age (33% of all cases). Males had a higher prevalence than females (57%). There was a preponderance of diagnoses in white individuals (82% of all cases) and more diagnoses in the Pacific Coast region (49% of all cases). Distant metastases were present at initial diagnosis in 8.7%. Surgery was performed in almost all patients, and gross total resection was achieved in 77%. The overall rate of survival was 77.8% at five years; age, sex, race, and geographical region of diagnosis were not associated with differences in survival outcomes. Patients with no radiotherapy had a lower rate of survival compared to patients with postoperative radiotherapy (mean difference = 19.7%; [95% CI 1.4%-38.0%], p = 0.0314). However, radiotherapy did not improve survival outcomes in patients undergoing chemotherapeutic treatment to a degree with any statistical significance. There was no statistically significant improvement in survival for patients undergoing radiotherapy prior to procedure when compared to patients with no radiotherapy.

Conclusions

In patients undergoing chemotherapeutic treatment for the DNMB subtype of medulloblastoma specifically, additional radiotherapy may offer only minimal benefit to the survival outcome. It is essential continued clinical trials be performed for the purpose of devising alternate treatments to radiotherapy.

Molecular subgrouping of medulloblastoma based on few-shot learning of multitasking using conventional MR images: a retrospective multicenter study

Background

The determination of molecular subgroups—wingless (WNT), sonic hedgehog (SHH), Group 3, and Group 4—of medulloblastomas is very important for prognostication and risk-adaptive treatment strategies. Due to the rare disease characteristics of medulloblastoma, we designed a unique multitask framework for the few-shot scenario to achieve noninvasive molecular subgrouping with high accuracy.

Methods

We introduced a multitask technique based on mask regional convolutional neural network (Mask-RCNN). By effectively utilizing the comprehensive information including genotyping, tumor mask, and prognosis, multitask technique, on the one hand, realized multi-purpose modeling and simultaneously, on the other hand, promoted the accuracy of the molecular subgrouping. One hundred and thirteen medulloblastoma cases were collected from 4 hospitals during the 8-year period in the retrospective study, which were divided into 3-fold cross-validation cohorts (N = 74) from 2 hospitals and independent testing cohort (N = 39) from the other 2 hospitals. Comparative experiments of different auxiliary tasks were designed to illustrate the effect of multitasking in molecular subgrouping.

Results

Compared to the single-task framework, the multitask framework that combined 3 tasks increased the average accuracy of molecular subgrouping from 0.84 to 0.93 in cross-validation and from 0.79 to 0.85 in independent testing. The average area under the receiver operating characteristic curves (AUCs) of molecular subgrouping were 0.97 in cross-validation and 0.92 in independent testing. The average AUCs of prognostication also reached to 0.88 in cross-validation and 0.79 in independent testing. The tumor segmentation results achieved the Dice coefficient of 0.90 in both cohorts.

Conclusions

The multitask Mask-RCNN is an effective method for the molecular subgrouping and prognostication of medulloblastomas with high accuracy in few-shot learning.

Neurocognitive functioning and health-related quality of life in adult medulloblastoma patients: long-term outcomes of the NOA-07 study

Background

Combined radiochemotherapy followed by maintenance chemotherapy with cisplatin, lomustine and vincristine within the NOA-07 study resulted in considerable short-term toxicity in adult medulloblastoma patients. Here we investigated the long-term impact of this treatment, focusing on neurocognitive functioning and health-related quality of life (HRQoL).

Methods

Neurocognitive functioning and HRQoL scores over time were determined, and differences between the post-treatment and follow-up assessments were calculated up to 18 months for neurocognition and 60 months for HRQoL.

Results

28/30 patients were analyzed. The three preselected HRQoL scales (role, social and cognitive functioning) showed improved scores, to a clinically relevant extent (≥ 10 points), compared to post-treatment levels up to 30 months, but decreased afterwards. Z-scores for verbal working memory were worse during follow-up compared to post-treatment scores and remained impaired during 18 months follow-up (i.e. z-score below − 1 standard deviation). Attention was impaired post-treatment, and remained impaired to a clinically relevant extent during follow-up. Coordination/processing speed and lexical verbal fluency improved compared to post-treatment scores, and remained within the normal range thereafter. Other tests of verbal fluency were stable over time, with z-scores within the normal range.

Conclusions

This long-term follow-up study showed that the NOA-07 treatment regimen was not associated with a deterioration in HRQoL in the post-treatment period. Verbal working memory deteriorated, while other neurocognitive domains did not seem to be impacted negatively by the treatment.

Electronic supplementary material

The online version of this article (10.1007/s11060-020-03502-y) contains supplementary material, which is available to authorized users.

Nomograms based on preoperative multiparametric magnetic resonance imaging for prediction of molecular subgrouping in medulloblastoma: results from a radiogenomics study of 111 patients

Background

Novel biological insights have led to consensus classification of medulloblastoma into 4 distinct molecular subgroups-wingless (WNT), sonic hedgehog (SHH), Group 3, and Group 4. We aimed to predict molecular subgrouping in medulloblastoma based on preoperative multiparametric magnetic resonance imaging (MRI) characteristics.

Methods

A set of 19 MRI features were evaluated in 111 patients with histologic diagnosis of medulloblastoma for prediction of molecular subgrouping. MRI characteristics were correlated with molecular subgroups derived from tissue samples in 111 patients (WNT = 17, SHH = 44, Group 3 = 27, and Group 4 = 23). Multinomial logistic regression of imaging parameters was performed on a training cohort (TC) of 76 patients, representing two-thirds of randomly selected patients from each of 4 molecular subgroups, to generate binary nomograms. Validation of these nomograms was performed on the remaining 35 patients as the validation cohort (VC).

Results

Medulloblastoma subgroups could be accurately predicted by preoperative MRI features in 74% of cases. Predictive accuracy was excellent for SHH (95%), acceptably high for Group 4 (78%), modest for Group 3 (56%) and worst for WNT (41%) subgroup medulloblastoma. SHH-specific nomogram was associated with excellent correlation between TC and VC, with area under the curve (AUC) of 0.939 and 0.991, respectively. AUC for Group 4 was acceptable at 0.851 and 0.788 in TC and VC, respectively; however, these values were consistently suboptimal in WNT and Group 3 medulloblastoma.

Conclusion

The predictive accuracy of MRI-based nomograms was excellent for SHH and encouraging for Group 4 medulloblastoma. Further work is needed for Group 3 and WNT-pathway medulloblastoma.

[Dendritic cell vaccines in neurological oncology]

Dendritic cell-based vaccines are an intensively studied active immunotherapy technology. Aim of this article is to review the results of the key clinical studies of such vaccines in the treatment of neuro-oncological diseases. Their effectiveness was studied most widely in the treatment of malignant glial tumors, the study went from experimental work to phase III clinical studies, preliminary results of which indicate some positive results of this immunotherapy method in adults. Currently, emphasis is also being placed on the identification of clinical and immunological correlates of the patient's response to therapy and on the search for new antigens for sensitization of dendritic cells Studies of dendritic cell vaccines also include a number of other neuro-oncological diseases. A separate part of this article is devoted to the treatment of intracerebral tumors in children, for example, medulloblastomas and gliomas of the pons. In addition, the potential use of dendritic cell vaccines for intracerebral metastases is considered.

Molecular Heterogeneity and Cellular Diversity: Implications for Precision Treatment in Medulloblastoma

Medulloblastoma, the most common pediatric malignant brain tumor, continues to have a high rate of morbidity and mortality in childhood. Recent advances in cancer genomics, single-cell sequencing, and sophisticated tumor models have revolutionized the characterization and stratification of medulloblastoma. In this review, we discuss heterogeneity associated with four major subgroups of medulloblastoma (WNT, SHH, Group 3, and Group 4) on the molecular and cellular levels, including histological features, genetic and epigenetic alterations, proteomic landscape, cell-of-origin, tumor microenvironment, and therapeutic approaches. The intratumoral molecular heterogeneity and intertumoral cellular diversity clearly underlie the divergent biology and clinical behavior of these lesions and highlight the future role of precision treatment in this devastating brain tumor in children.

Relative survival after diagnosis with a primary brain or other central nervous system tumor in the National Program of Cancer Registries, 2004 to 2014

Background

The majority of reported cancer survival statistics in the United States are generated using the National Cancer Institute's publicly available Surveillance, Epidemiology, and End Results (SEER) data, which prior to 2019 represented 28% of the US population (now 37%). In the case of rare cancers or special subpopulations, data sets based on a larger portion of the US population may contribute new insights into these low-incidence cancers. The purpose of this study is to characterize the histology-specific survival patterns for all primary malignant and nonmalignant primary brain tumors in the United States using the Centers for Disease Control and Prevention's National Program of Cancer Registries (NPCR).

Methods

Survival data were obtained from the NPCR (includes data from 39 state cancer registries, representing 81% of the US population). Relative survival rates (RS) with 95% CI were generated using SEER*Stat 8.3.5 from 2004 to 2014 by behavior, histology, sex, race/ethnicity, and age at diagnosis.

Results

Overall, there were 488 314 cases from 2004 to 2014. Overall 5-year RS was 69.8% (95% CI = 69.6%-69.9%). Five-year RS was 35.9% (95% CI = 35.6%-36.1%) for malignant and 90.2% (95% CI = 90.1%-90.4%) for nonmalignant tumors. Pilocytic astrocytoma had the longest 5-year RS (94.2%, 95% CI = 93.6%-94.6%) of all glioma subtypes, whereas glioblastoma had the shortest 5-year RS (6.1%, 95% CI = 6.0%-6.3%). Nonmalignant nerve sheath tumors had the longest 5-year RS (99.3%, 95% CI = 99.1%-99.4%). Younger age and female sex were associated with increased survival for many histologies.

Conclusions

Survival after diagnosis with primary brain tumor varies by behavior, histology, and age. Using such a database that includes more than 80% of the US population may represent national survival patterns.

Pediatric Patients With SHH Medulloblastoma Fail Differently as Compared With Adults: Possible Implications for Treatment Modifications

PURPOSE

The purpose of this work was to study the diversity of sonic hedgehog (SHH) medulloblastoma across different age groups with an emphasis on patterns of relapse.

METHODS

All data for the study were obtained through review of medical records, imaging, radiation charts, treatment planning, and chemotherapy details.

RESULTS

Sixty-three patients with SHH medulloblastoma were identified from a prospectively maintained database and classified into 3 groups-infantile: ≤3 years (i-SHH, n=11); pediatric: >3 to <18 years (p-SHH, n=21); and adult: ≥18 years (a-SHH; n=31). Lateralized tumors were common with increasing age (81% a-SHH, 67% p-SHH, 27% i-SHH; P=0.01). Large cell anaplastic histology was relatively common for p-SHH (33%), while the nodular/desmoplastic variant was more frequent in i-SHH (64%) and adults (51%). Median follow-up was 38 months (range, 5 to 91 mo). Five-year event-free survival was 80%, 31%, and 52% for i-SHH, p-SHH, and a-SHH, respectively (P=0.001). Median time to failure for p-SHH and a-SHH were 12 and 36 months, respectively. For p-SHH, 83% were metastatic relapses compared with localized failure in 75% for a-SHH. Five-year overall survival for i-SHH, p-SHH, and a-SHH were 91%, 31%, and 70%, respectively (P=0.001). On univariate analysis, event-free survival was significantly worse for superiorly located tumors (P=0.01), nondesmoplastic histology (P=0.02), and histology alone for overall survival (P=0.04) (none on multivariate analysis).

CONCLUSIONS

SHH medulloblastoma demonstrates varied outcomes depending on age, with p-SHH associated with early and metastatic relapses, while for a-SHH it tends to be delayed and localized.

An oncolytic measles virus-sensitive Group 3 medulloblastoma model in immune-competent mice

Background

Oncolytic measles virus (MV) is effective in xenograft models of many tumor types in immune-compromised mice. However, no murine cell line exists that is tumorigenic, grows in immune-competent mice, and is killed by MV. The lack of such a model prevents an examination of the effect of the immune system on MV oncotherapy.

Methods

Cerebellar stem cells from human CD46-transgenic immunocompetent mice were transduced to express Sendai virus C-protein, murine C-Myc, and Gfi1b proteins. The resultant cells were injected into the brain of NSG mice, and a cell line, called CSCG, was prepared from the resulting tumor.

Results

CSCG cells are highly proliferative, and express stem cell markers. These cells are permissive for replication of MV and are killed by the virus in a dose- and time-dependent manner. CSCG cells form aggressive tumors that morphologically resemble medulloblastoma when injected into the brains of immune-competent mice. On the molecular level, CSCG tumors overexpress natriuretic peptide receptor 3 and gamma-aminobutyric acid type A receptor alpha 5, markers of Group 3 medulloblastoma. A single intratumoral injection of MV‒green fluorescent protein resulted in complete tumor regression and prolonged survival of animals compared with treatments with phosphate buffered saline (P = 0.0018) or heat-inactivated MV (P = 0.0027).

Conclusions

This immune-competent model provides the first platform to test therapeutic regimens of oncolytic MV for Group 3 medulloblastoma in the presence of anti-measles immunity. The strategy presented here can be used to make MV-sensitive murine models of any human tumor for which the driving mutations are known.

Worldwide Trends in Survival From Common Childhood Brain Tumors: A Systematic Review

PURPOSE

The histology of brain tumors determines treatment and predicts outcome. Population-based survival reflects the effectiveness of a health care system in managing cancer. No systematic review of worldwide variation and time trends in survival from brain tumors in children is currently available.

PATIENTS AND METHODS

We considered longitudinal, observational studies comprising children diagnosed with intracranial astrocytic or embryonal tumors. We searched six electronic databases from database inception to September 30, 2018, using complex search strategies. The outcome measure was 5-year survival, estimated through a time-to-event analysis. This study is registered with PROSPERO, number CRD42018111981.

RESULTS

Among 5,244 studies, we identified 47 eligible articles that provided 228 survival estimates. Only five studies were entirely or partially conducted in low-income or middle-income countries. Five-year survival from embryonal tumors increased from 37% in 1980 to approximately 60% in 2009. Although survival for medulloblastoma improved substantially (from 29% to 73% during 1959-2009), survival for primitive neuroectodermal tumors wavered over time (1973-2009) and between countries. Five-year survival from astrocytoma changed very little over the 27 years between 1982 and 2009 (from 78% to 89%). Interpretation of the literature was made difficult by the heterogeneity of study designs.

CONCLUSION

Survival has improved for embryonal tumors, but little change has been observed for astrocytic tumors. We found a striking gap in knowledge about survival from childhood brain tumor subtypes in middle-income and low-income countries, where half of these tumors are diagnosed. Larger studies are needed, including in under-represented countries and based on standardized data collection, to provide up-to-date survival estimates.

The histone code reader PHD finger protein 7 controls sex-linked disparities in gene expression and malignancy in Drosophila

The notable male predominance across many human cancer types remains unexplained. Here, we show that Drosophila l(3)mbt brain tumors are more invasive and develop as malignant neoplasms more often in males than in females. By quantitative proteomics, we have identified a signature of proteins that are differentially expressed between male and female tumor samples. Prominent among them is the conserved chromatin reader PHD finger protein 7 (Phf7). We show that Phf7 depletion reduces sex-dependent differences in gene expression and suppresses the enhanced malignant traits of male tumors. Our results identify potential regulators of sex-linked tumor dimorphism and show that these genes may serve as targets to suppress sex-linked malignant traits.

Partnership for defining the impact of 12 selected rare CNS tumors: a report from the CBTRUS and the NCI-CONNECT

PURPOSE

Population-based cancer statistics, including histology-specific incidence, prevalence, and survival are essential to evaluating the total burden due to disease in a population. The National Cancer Institute's (NCI) Comprehensive Oncology Network Evaluating Rare CNS Tumors (NCI-CONNECT) was developed to better understand tumor biology and patient outcomes for 12 selected brain and other central nervous system (CNS) tumor histologies that are rare in adults to improve approaches to care and treatment. The aim of this study was to determine the incidence, prevalence, and survival of these selected rare histologies.

METHODS

Data from the Central Brain Tumor Registry of the United States (CBTRUS) from 2000 to 2014 were used to calculate average annual age-adjusted incidence rates (AAIR) per 100,000 population overall and by sex, race, ethnicity, and age. NCI's Surveillance, Epidemiology and End Results (SEER) data were used to calculate relative survival (RS) estimates. Point prevalence for 2014 was estimated using annual age-specific incidence and survival from CBTRUS and SEER, respectively.

RESULTS

Overall AAIR was 1.47 per 100,000 for all 12 rare histologies combined, with the highest histology-specific incidence in oligodendrogliomas (AAIR = 0.40/100,000). Overall, most histologies were more common in males, adults (age 40 + ), Whites, and non-Hispanics. Ependymomas were the most prevalent histology at 4.11 per 100,000; followed by oligodendrogliomas at 3.68 per 100,000. Relative survival at 1-, 5-, and 10-years was 82.3%, 64.0%, and 55.4%, respectively for all 12 selected brain and other CNS tumor types combined. Ependymomas had the highest RS (1-year = 94.2%, 5-year = 83.9%, 10-year = 78.6%) and gliosarcomas had the lowest relative survival rate (1-year = 42.5%, 5-year = 5.6%, 10-year = 2.9%) at all three time points.

CONCLUSIONS

Incidence and prevalence of these rare brain and other CNS tumor histologies have not been previously reported. Along with survival, these data provide a statistical foundation to understand the impact of these cancers and provide important disease-specific data for the design of prospective clinical trials.