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Background: Although cavitating ultrasonic aspirators are commonly used in neurosurgical procedures, the suitability of ultrasonic aspirator-derived tumor material for diagnostic procedures is still controversial. Here, we explore the feasibility of using ultrasonic aspirator-resected tumor tissue to classify otherwise discarded sample material by fast DNA methylation-based analysis using low pass nanopore whole genome sequencing. Methods: Ultrasonic aspirator-derived specimens from pediatric patients undergoing brain tumor resection were subjected to low-pass nanopore whole genome sequencing. DNA methylation-based classification using a neural network classifier and copy number variation analysis were performed. Tumor purity was estimated from copy number profiles. Results were compared to microarray (EPIC)-based routine neuropathological histomorphological and molecular evaluation. Results: 19 samples with confirmed neuropathological diagnosis were evaluated. All samples were successfully sequenced and passed quality control for further analysis. DNA and sequencing characteristics from ultrasonic aspirator-derived specimens were comparable to routinely processed tumor tissue. Classification of both methods was concordant regarding methylation class in 17/19 (89%) cases. Application of a platform-specific threshold for nanopore-based classification ensured a specificity of 100%, whereas sensitivity was 79%. Copy number variation profiles were generated for all cases and matched EPIC results in 18/19 (95%) samples, even allowing the identification of diagnostically or therapeutically relevant genomic alterations. Conclusion: Methylation-based classification of pediatric CNS tumors based on ultrasonic aspirator-reduced and otherwise discarded tissue is feasible using time- and cost-efficient nanopore sequencing. [ABSTRACT FROM AUTHOR]

Posterior fossa type A (PF-EPN-A, PFA) ependymoma are aggressive tumors that mainly affect children and have a poor prognosis. Histopathology shows significant intratumoral heterogeneity, ranging from loose tissue to often sharply demarcated, extremely cell-dense tumor areas. To determine molecular differences in morphologically different areas and to understand their clinical significance, we analyzed 113 PF-EPN-A samples, including 40 corresponding relapse samples. Cell-dense areas ranged from 0 to 100% of the tumor area and displayed a higher proportion of proliferating tumor cells (p < 0.01). Clinically, cell density was associated with poor progression-free and overall survival (pPFS = 0.0026, pOS < 0.01). Molecularly, tumor areas with low and high cell density showed diverging DNA methylation profiles regarding their similarity to distinct previously discovered PF-EPN-A subtypes in 9/21 cases. Prognostically relevant chromosomal changes at 1q and 6q showed spatial heterogeneity within single tumors and were significantly enriched in cell-dense tumor areas as shown by single-cell RNA (scRNA)-sequencing as well as copy number profiling and fluorescence in situ hybridization (FISH) analyses of different tumor areas. Finally, spatial transcriptomics revealed cell-dense areas of different tumors to be more similar than various different areas of the same tumor. High-density areas distinctly overexpressed genes encoding histone proteins, WNT5A, TGFB1, or IGF2. Relapsing tumors displayed a higher proportion of cell-dense areas (p = 0.036), a change in PF-EPN-A methylation subtypes (13/32 patients), and novel chromosome 1q gains and 6q losses (12/32 cases) compared to corresponding primary tumors. Our data suggest that PF-EPN-A ependymomas habor a previously unrecognized intratumoral heterogeneity with clinical implications, which has to be accounted for when selecting diagnostic material, inter alia, by histological evaluation of the proportion of cell-dense areas. [ABSTRACT FROM AUTHOR]

Molecular groups of medulloblastoma (MB) are well established. Novel risk stratification parameters include Group 3/4 (non-WNT/non-SHH) methylation subgroups I–VIII or whole-chromosomal aberration (WCA) phenotypes. This study investigates the integration of clinical and molecular parameters to improve risk stratification of non-WNT/non-SHH MB. Non-WNT/non-SHH MB from the HIT2000 study and the HIT-MED registries were selected based on availability of DNA-methylation profiling data. MYC or MYCN amplification and WCA of chromosomes 7, 8, and 11 were inferred from methylation array-based copy number profiles. In total, 403 non-WNT/non-SHH MB were identified, 346/403 (86%) had a methylation class family Group 3/4 methylation score (classifier v11b6) ≥ 0.9, and 294/346 (73%) were included in the risk stratification modeling based on Group 3 or 4 score (v11b6) ≥ 0.8 and subgroup I–VIII score (mb_g34) ≥ 0.8. Group 3 MB (5y-PFS, survival estimation ± standard deviation: 41.4 ± 4.6%; 5y-OS: 48.8 ± 5.0%) showed poorer survival compared to Group 4 (5y-PFS: 68.2 ± 3.7%; 5y-OS: 84.8 ± 2.8%). Subgroups II (5y-PFS: 27.6 ± 8.2%) and III (5y-PFS: 37.5 ± 7.9%) showed the poorest and subgroup VI (5y-PFS: 76.6 ± 7.9%), VII (5y-PFS: 75.9 ± 7.2%), and VIII (5y-PFS: 66.6 ± 5.8%) the best survival. Multivariate analysis revealed subgroup in combination with WCA phenotype to best predict risk of progression and death. The integration of clinical (age, M and R status) and molecular (MYC/N, subgroup, WCA phenotype) variables identified a low-risk stratum with a 5y-PFS of 94 ± 5.7 and a very high-risk stratum with a 5y-PFS of 29 ± 6.1%. Validation in an international MB cohort confirmed the combined stratification scheme with 82.1 ± 6.0% 5y-PFS in the low and 47.5 ± 4.1% in very high-risk groups, and outperformed the clinical model. These newly identified clinico-molecular low-risk and very high-risk strata, accounting for 6%, and 21% of non-WNT/non-SHH MB patients, respectively, may improve future treatment stratification. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the clinical impact of isolated spread of medulloblastoma cells into cerebrospinal fluid without additional macroscopic metastases (M1-only). Methods: The HIT-MED database was searched for pediatric patients with M1-only medulloblastoma diagnosed from 2000 to 2019. Corresponding clinical and molecular data was evaluated. Treatment was stratified by age and changed over time for older patients. Results: 70 patients with centrally reviewed M1-only disease were identified. Clinical data was available for all and molecular data for 45/70 cases. 91% were non-WNT/non-SHH medulloblastoma (Grp3/4). 5-year PFS for 52 patients ≥ 4 years was 59.4 (± 7.1) %, receiving either upfront craniospinal irradiation (CSI) or SKK-sandwich chemotherapy (CT). Outcomes did not differ between these strategies (5-year PFS: CSI 61.7 ± 9.9%, SKK-CT 56.7 ± 6.1%). For patients < 4 years (n = 18), 5-year PFS was 50.0 (± 13.2) %. M1-persistence occurred exclusively using postoperative CT and was a strong negative predictive factor (pPFS/OS < 0.01). Patients with additional clinical or molecular high-risk (HR) characteristics had worse outcomes (5-year PFS 42.7 ± 10.6% vs. 64.0 ± 7.0%, p = 0.03). In n = 22 patients ≥ 4 years with full molecular information and without additional HR characteristics, risk classification by molecular subtyping had an effect on 5-year PFS (HR 16.7 ± 15.2%, SR 77.8 ± 13.9%; p = 0.01). Conclusions: Our results confirm that M1-only is a high-risk condition, and further underline the importance of CSF staging. Specific risk stratification of affected patients needs attention in future discussions for trials and treatment recommendations. Future patients without contraindications may benefit from upfront CSI by sparing risks related to higher cumulative CT applied in sandwich regimen. [ABSTRACT FROM AUTHOR]

Recent genomic studies have shed light on the biology and inter-tumoral heterogeneity underlying pineal parenchymal tumors, in particular pineoblastomas (PBs) and pineal parenchymal tumors of intermediate differentiation (PPTIDs). Previous reports, however, had modest sample sizes and lacked the power to integrate molecular and clinical findings. The different proposed molecular group structures also highlighted a need to reach consensus on a robust and relevant classification system. We performed a meta-analysis on 221 patients with molecularly characterized PBs and PPTIDs. DNA methylation profiles were analyzed through complementary bioinformatic approaches and molecular subgrouping was harmonized. Demographic, clinical, and genomic features of patients and samples from these pineal tumor groups were annotated. Four clinically and biologically relevant consensus PB groups were defined: PB-miRNA1 (n = 96), PB-miRNA2 (n = 23), PB-MYC/FOXR2 (n = 34), and PB-RB1 (n = 25). A final molecularly distinct group, designated PPTID (n = 43), comprised histological PPTID and PBs. Genomic and transcriptomic profiling allowed the characterization of oncogenic drivers for individual tumor groups, specifically, alterations in the microRNA processing pathway in PB-miRNA1/2, MYC amplification and FOXR2 overexpression in PB-MYC/FOXR2, RB1 alteration in PB-RB1, and KBTBD4 insertion in PPTID. Age at diagnosis, sex predilection, and metastatic status varied significantly among tumor groups. While patients with PB-miRNA2 and PPTID had superior outcome, survival was intermediate for patients with PB-miRNA1, and dismal for those with PB-MYC/FOXR2 or PB-RB1. Reduced-dose CSI was adequate for patients with average-risk, PB-miRNA1/2 disease. We systematically interrogated the clinical and molecular heterogeneity within pineal parenchymal tumors and proposed a consensus nomenclature for disease groups, laying the groundwork for future studies as well as routine use in tumor diagnostic classification and clinical trial stratification. [ABSTRACT FROM AUTHOR]

Embryonal tumor with Multilayered Rosettes (ETMR) is a relatively rare but typically deadly type of brain tumor that occurs mostly in infants. Since the discovery of the characteristic chromosome 19 miRNA cluster (C19MC) amplification a decade ago, the methods for diagnosing this entity have improved and many new insights in the molecular landscape of ETMRs have been acquired. All ETMRs, despite their highly heterogeneous histology, are characterized by specific high expression of the RNA-binding protein LIN28A, which is, therefore, often used as a diagnostic marker for these tumors. ETMRs have few recurrent genetic aberrations, mainly affecting the miRNA pathway and including amplification of C19MC (embryonal tumor with multilayered rosettes, C19MC-altered) and mutually exclusive biallelic DICER1 mutations of which the first hit is typically inherited through the germline (embryonal tumor with multilayered rosettes, DICER1-altered). Identification of downstream pathways affected by the deregulated miRNA machinery has led to several proposed potential therapeutical vulnerabilities including targeting the WNT, SHH, or mTOR pathways, MYCN or chromosomal instability. However, despite those findings, treatment outcomes have only marginally improved, since the initial description of this tumor entity. Many patients do not survive longer than a year after diagnosis and the 5-year overall survival rate is still lower than 30%. Thus, there is an urgent need to translate the new insights in ETMR biology into more effective treatments. Here, we present an overview of clinical and molecular characteristics of ETMRs and the current progress on potential targeted therapies. [ABSTRACT FROM AUTHOR]

Tumors of the pineal region comprise several different entities with distinct clinical and histopathological features. Whereas some entities predominantly affect adults, pineoblastoma (PB) constitutes a highly aggressive malignancy of childhood with a poor outcome. PBs mainly arise sporadically, but may also occur in the context of cancer predisposition syndromes including DICER1 and RB1 germline mutation. With this study, we investigate clinico-pathological subgroups of pineal tumors and further characterize their biological features. We performed genome-wide DNA methylation analysis in 195 tumors of the pineal region and 20 normal pineal gland controls. Copy-number profiles were obtained from DNA methylation data; gene panel sequencing was added for 93 tumors and analysis was further complemented by miRNA sequencing for 22 tumor samples. Unsupervised clustering based on DNA methylation profiling separated known subgroups, like pineocytoma, pineal parenchymal tumor of intermediate differentiation, papillary tumor of the pineal region and PB, and further distinct subtypes within these groups, including three subtypes within the core PB subgroup. The novel molecular subgroup Pin-RB includes cases of trilateral retinoblastoma as well as sporadic pineal tumors with RB1 alterations, and displays similarities with retinoblastoma. Distinct clinical associations discriminate the second novel molecular subgroup PB-MYC from other PB cases. Alterations within the miRNA processing pathway (affecting DROSHA, DGCR8 or DICER1) are found in about two thirds of cases in the three core PB subtypes. Methylation profiling revealed biologically distinct groups of pineal tumors with specific clinical and molecular features. Our findings provide a foundation for further clinical as well as molecular and functional characterization of PB and other pineal tumors, including the role of miRNA processing defects in oncogenesis. [ABSTRACT FROM AUTHOR]

Purpose: Epigenetic profiling has recently identified clinically and molecularly distinct subgroups of ependymoma. The 2016 World Health Organization (WHO) classification recognized supratentorial ependymomas (ST-EPN) with REL-associated protein/p65 (RELA) fusion as a clinicopathological entity. These tumors represent 70% of pediatric ST-EPN characterized by recurrent C11orf95-RELA fusion transcripts, which lead to pathological activation of the nuclear factor 'kappa-light-chain-enhancer' of activated B-cells (NF-κB) signaling pathway. Cyclin-dependent kinase inhibitor 2A (CDKN2A) inactivation has also been reported to correlate with poor prognosis. Here, we systematically describe magnetic resonance imaging (MRI) characteristics of RELA-fused ST-EPN, with respect to CDKN2A deletion status. Methods: Our cohort of patients with ST-EPN (n = 57) was obtained from the database of the German Brain Tumor Reference Center of the German Society for Neuropathology and Neuroanatomy (DGNN), and tumors were diagnosed according to the 2016 WHO classification. Molecular characterization identified 47 RELA-fused tumors. We analyzed the preoperative MRI according to standardized criteria, and comparison was performed between CDKN2A altered (n = 21) and CDKN2A wild type (n = 26) tumors. Results: The RELA-fused ST-EPN showed a spectrum of predominantly hemispheric tumors with cysts and necrosis. Statistical analysis on CDKN2A status revealed significant differences in terms of younger manifestation age (p =0.002) and more intratumoral hemorrhage in T2-weighted imaging (T2WI) (p =0.010) in wild type tumors; however, the location was not a parameter for differentiation. Conclusion: This study first provides comprehensive MRI data for RELA-fused ST-EPN as a distinct entity, with further interest on CDKN2A genomic status. Patient stratification by morphological MRI alone seems difficult at present. The results may support ongoing research in ST-EPN within the framework of the radiogenomics concept. [ABSTRACT FROM AUTHOR]

Multiple independent genomic profiling efforts have recently identified clinically and molecularly distinct subgroups of ependymoma arising from all three anatomic compartments of the central nervous system (supratentorial brain, posterior fossa, and spinal cord). These advances motivated a consensus meeting to discuss: (1) the utility of current histologic grading criteria, (2) the integration of molecular-based stratification schemes in future clinical trials for patients with ependymoma and (3) current therapy in the context of molecular subgroups. Discussion at the meeting generated a series of consensus statements and recommendations from the attendees, which comment on the prognostic evaluation and treatment decisions of patients with intracranial ependymoma (WHO Grade II/III) based on the knowledge of its molecular subgroups. The major consensus among attendees was reached that treatment decisions for ependymoma (outside of clinical trials) should not be based on grading (II vs III). Supratentorial and posterior fossa ependymomas are distinct diseases, although the impact on therapy is still evolving. Molecular subgrouping should be part of all clinical trials henceforth. [ABSTRACT FROM AUTHOR]

The HIT-SIOP-PNET4 randomised trial for standard risk medulloblastoma (MB) (2001-2006) included 338 patients and compared hyperfractionated and conventional radiotherapy. We here report the long-term outcome after a median follow up of 7.8 years, including detailed information on relapse and the treatment of relapse. Data were extracted from the HIT Group Relapsed MB database and by way of a specific case report form. The event-free and overall (OS) survival at 10 years were 76 ± 2 % and 78 ± 2 % respectively with no significant difference between the treatment arms. Seventy-two relapses and three second malignant neoplasms were reported. Thirteen relapses (18 %) were isolated local relapses in the posterior fossa (PF) and 59 (82 %) were craniospinal, metastatic relapses (isolated or multiple) with or without concurrent PF disease. Isolated PF relapse vs all other relapses occurred at mean/median of 38/35 and 28/26 months respectively (p = 0.24). Late relapse, i.e. >5 years from diagnosis, occurred in six patients (8 %). Relapse treatment consisted of combinations of surgery (25 %), focal radiotherapy (RT 22 %), high dose chemotherapy with stem cell rescue (HDSCR 21 %) and conventional chemotherapy (90 %). OS at 5 years after relapse was 6.0 ± 4 %. In multivariate analysis; isolated relapse in PF, and surgery were significantly associated with prolonged survival whereas RT and HDSCR were not. Survival after relapse was not related to biological factors and was very poor despite several patients receiving intensive treatments. Exploration of new drugs is warranted, preferably based on tumour biology from biopsy of the relapsed tumour. [ABSTRACT FROM AUTHOR]

Historical risk stratification criteria for medulloblastoma rely primarily on clinicopathological variables pertaining to age, presence of metastases, extent of resection, histological subtypes and in some instances individual genetic aberrations such as MYC and MYCN amplification. In 2010, an international panel of experts established consensus defining four main subgroups of medulloblastoma (WNT, SHH, Group 3 and Group 4) delineated by transcriptional profiling. This has led to the current generation of biomarker-driven clinical trials assigning WNT tumors to a favorable prognosis group in addition to clinicopathological criteria including MYC and MYCN gene amplifications. However, outcome prediction of non-WNT subgroups is a challenge due to inconsistent survival reports. In 2015, a consensus conference was convened in Heidelberg with the objective to further refine the risk stratification in the context of subgroups and agree on a definition of risk groups of non-infant, childhood medulloblastoma (ages 3-17). Published and unpublished data over the past 5 years were reviewed, and a consensus was reached regarding the level of evidence for currently available biomarkers. The following risk groups were defined based on current survival rates: low risk (>90 % survival), average (standard) risk (75-90 % survival), high risk (50-75 % survival) and very high risk (<50 % survival) disease. The WNT subgroup and non-metastatic Group 4 tumors with whole chromosome 11 loss or whole chromosome 17 gain were recognized as low-risk tumors that may qualify for reduced therapy. High-risk strata were defined as patients with metastatic SHH or Group 4 tumors, or MYCN-amplified SHH medulloblastomas. Very high-risk patients are Group 3 with metastases or SHH with TP53 mutation. In addition, a number of consensus points were reached that should be standardized across future clinical trials. Although we anticipate new data will emerge from currently ongoing and recently completed clinical trials, this consensus can serve as an outline for prioritization of certain molecular subsets of tumors to define and validate risk groups as a basis for future clinical trials. [ABSTRACT FROM AUTHOR]

This study aimed to prospectively evaluate clinical, histopathological and molecular variables for outcome prediction in medulloblastoma patients. Patients from the HIT2000 cooperative clinical trial were prospectively enrolled based on the availability of sufficient tumor material and complete clinical information. This revealed a cohort of 184 patients (median age 7.6 years), which was randomly split at a 2:1 ratio into a training ( n = 127), and a test ( n = 57) dataset in order to build and test a risk score for this population. Independent validation was performed in a non-overlapping cohort ( n = 83). All samples were subjected to thorough histopathological investigation, CTNNB1 mutation analysis, quantitative PCR, MLPA and FISH analyses for cytogenetic variables, and methylome analysis. By univariable analysis, clinical factors (M-stage), histopathological variables (large cell component, endothelial proliferation, synaptophysin pattern), and molecular features (chromosome 6q status, MYC amplification, subgrouping) were found to be prognostic. Molecular consensus subgrouping (WNT, SHH, Group 3, Group 4) was validated as an independent feature to stratify patients into different risk groups. When comparing methods for the identification of WNT-driven medulloblastoma, this study identified CTNNB1 sequencing and methylation profiling to most reliably identify these patients. After removing patients with particularly favorable ( CTNNB1 mutation, extensive nodularity) or unfavorable ( MYC amplification) markers, a risk score for the remaining 'intermediate molecular risk' population dependent on age, M-stage, pattern of synaptophysin expression, and MYCN copy-number status was identified, with speckled synaptophysin expression indicating worse outcome. Test and independent validation of the score confirmed significant discrimination of patients by risk profile. Methylation subgrouping and CTNNB1 mutation status represent robust tools for the risk stratification of medulloblastoma. A simple clinico-pathological risk score was identified, which was confirmed in a test set and by independent clinical validation. [ABSTRACT FROM AUTHOR]

Central nervous system primitive neuroectodermal tumors (CNS-PNET) and pineoblastomas (PBL) are rare in adulthood. Knowledge on clinical outcome and the efficacy and toxicities of chemotherapy in addition to radiotherapy is limited. Patients older than 21 years at diagnosis were followed in the observational arm of the prospective pediatric multicenter trial HIT 2000. After surgery, craniospinal irradiation and maintenance or sandwich chemotherapy were recommended. Radiotherapy was normo- (35.2 Gy; tumor region, 55.0 Gy; metastasis, 49.6 Gy) or hyperfractionated (40.0 Gy; tumor bed, 68.0 Gy; metastasis, 50-60 Gy). Maintenance chemotherapy consisted of eight courses (vincristine, lomustine, cisplatin). Sandwich chemotherapy included two cycles of postoperative chemotherapy followed by radiotherapy, and four courses of maintenance chemotherapy. Seventeen patients (CNS-PNET, n = 7; PBL, n = 10), median age 30 years, were included. Eight patients had a postoperative residual tumor and four patients metastatic disease. The median follow-up of ten surviving patients was 41 months. The estimated rates for 3-year progression-free survival (PFS) and overall survival were 68 ± 12 and 66 ± 13 %, respectively. PBL compared to CNS-PNET tended towards a better PFS, although the difference was not clear ( p = 0.101). Both chemotherapeutic (maintenance, n = 6; sandwich, n = 8) protocols did not differ in their PFS and were feasible with acceptable toxicities. Intensified regimens of combined chemo- and radiotherapy are generally feasible in adults with CNS-PNET/PBL. The impact of intensified chemotherapy on survival should be further assessed. [ABSTRACT FROM AUTHOR]

Purely intracranial soft tissue sarcomas (ISTS) are very rare among children. A retrospective database analysis of the Cooperative Weichteilsarkom Studiengruppe (CWS) and brain tumor (HIT) registries was conducted to describe treatment and long-term outcome of children and adolescents with ISTS. Nineteen patients from Germany, Austria and Switzerland were reported between 1988 and 2009. Median age at diagnosis was 9.7 years (range, 0.5-17.8). Central pathological review was performed in 17 patients. Eleven patients underwent a total and five a subtotal tumor resection. A biopsy was done in one patient. In two patients no data concerning extent of initial resection was available. Radiotherapy was performed in 15 patients (first-line, n = 11; following progression, n = 4). All but one patient received chemotherapy (first-line, n = 7, following progression, n = 5; first-line and following progression, n = 6). With a median follow-up of 5.8 years (range, 0.6-19.8) ten patients were alive in either first or second complete remission. Seven patients died due to relapse or progression and two were alive with progressive disease. Estimated progression-free and overall survival at 5 years were 47 % (±12 %) and 74 % (±10 %), respectively. About 50 % of patients with ISTS remain relapse-free after 5 years. Multimodality treatment including complete tumor resection and radio-/chemotherapy is required to achieve sustained tumor control in patients with ISTS. Early initiation of postoperative non-surgical treatment seems to be important to prevent recurrence. Due to the intracranial localization local therapy should follow the recommendations used in brain tumors rather than in soft tissue sarcomas, whereas chemotherapy should be guided by histological subtype. [ABSTRACT FROM AUTHOR]

The mainstay of medulloblastoma treatment is high-quality interdisciplinary collaboration in diagnosis, treatment, and aftercare by all involved disciplines. The first step in treatment of medulloblastoma is a maximal safe surgery, followed by thorough staging. Surgery should only be performed in experienced neurosurgical centers, with age-appropriate postoperative care. As optimal risk stratification is based on histopathological and neuroradiological assessments, these should be performed or confirmed by experienced specialists. Central review of histopathological subtype, as well as review of staging evaluations is highly desirable. For young children with desmoplastic/nodular (DMB), or extensive nodular medulloblastoma, craniospinal or any radiotherapy should be avoided. For young children with classic medulloblastoma (CMB), large cell, or anaplastic medulloblastoma (LC/A MB) optimized strategies with high-dose chemotherapy and autologous stem cell rescue with or without local radiotherapy are under investigation. For older clinical standard risk patients (without metastases, without postoperative residual tumor >1.5 cm) with CMB or DMB, craniospinal radiotherapy with 23.4 Gy and boost to the posterior fossa to 54 Gy, followed by maintenance chemotherapy can be regarded as a standard therapy besides other currently applied regimen, such as the use of intensified chemotherapy after irradiation. Older children with LC/A MB, metastatic medulloblastoma, and/or large residual tumor can be regarded as high-risk patients and should receive intensified treatment: intensified chemotherapeutic regimen before or after radiotherapy with increased dose (36-Gy CSI normofractionated, or 40-Gy hyperfractionated) is used. For treatment to be effective, quality control of radiotherapy is of high relevance. Information on long-term sequelae is essential and appropriate multidisciplinary follow-up and support, including rehabilitation and help for reintegration, is necessary. Whenever possible, patients should be included in prospective studies, and tumor material should be sampled to facilitate further research on medulloblastoma biology, which will significantly influence the stratification criteria and the introduction of targeted therapies in standard treatment recommendations in the future. [ABSTRACT FROM AUTHOR]

Approximately 30-50% of patients with intracranial primitive neuroectodermal tumors (PNETs) of the central nervous system (CNS) develop spinal metastases. In contrast, primary spinal CNS-PNETs are extremely uncommon. The database and study records of the German/Austrian brain tumor trials HIT 91, HIT SKK 92, and HIT 2000 were retrospectively reviewed to describe clinical features, treatment modalities, and outcome of children with primary CNS-PNETs of the spinal cord who were registered as observational patients. Out of 1,248 patients with medulloblastomas or CNS-PNETs registered in the HIT database four patients (female, n = 3) with primary CNS-PNETs of the spinal cord were identified. Age at diagnosis was 10, 16, 23, and 174 months. Location of primary tumors was medulla oblongata-T3, C2-T1, T10-L2, T7-T10. Two patients had metastatic disease at diagnosis. Complete and incomplete resection was performed in one patient each, whereas two patients underwent a biopsy only. Two patients received chemotherapy only, in accordance with the HIT 91 trial (sandwich chemotherapy arm). They developed disease progression and died six months after diagnosis. One patient was given chemotherapy in accordance with the HIT 2000 trial followed by craniospinal radiotherapy and four courses of maintenance chemotherapy. The patient is in complete remission almost four years after diagnosis. The fourth patient developed disease progression while receiving induction chemotherapy. Hence, chemotherapy was switched to a modified Head Start protocol. After three cycles he underwent double autologous stem cell transplantation and craniospinal irradiation. Forty months after diagnosis the patient is alive and well, but surveillance MRIs still show nodular enhancing lesions in the area of the primary tumor and intracranial meningeal enhancement. Primary CNS-PNETs of the spinal cord probably require multimodal treatment including radiotherapy to achieve sustained tumor control. [ABSTRACT FROM AUTHOR]

Thirty-eight consecutive children treated according to the HIT2000 and HIT91 studies for medulloblastoma who suffered 40 recurrence events were identified from a neuroradiological database. Relapse was associated with younger median age compared with all children treated on HIT2000. Eight patients relapsed with isolated local recurrence. There was no correlation with incomplete surgical removal or violation of the respective treatment protocol. Four patients were younger than 4 years at time of initial presentation and thus were not treated primarily with radiotherapy, suggesting that delayed radiotherapy might be a contributing factor. Meningeal dissemination was present in 32 events; 16 were located in the frontal region, 8 of which were isolated nodular frontal and frontobasal meningeal disease. Circumscribed meningeal recurrences were associated with better overall survival (OS) compared with diffuse, widespread recurrences. Isolated frontobasal meningeal relapses are a well-known phenomenon in medulloblastomas even years after treatment and have been correlated to an underdose of radiation in many literature reports. However, in our patients there was no correlation to possible treatment violations, indicating that inadequate radiation dose to the frontobasal region was unlikely to be a causative factor. Surgical technique varied due to the multicentric nature of our study, so position during surgery was not recognized as a predisposing factor for frontobasal recurrence. [ABSTRACT FROM AUTHOR]

Ependymoblastoma is a rare malignant brain tumor of early childhood. Data on clinical behavior and optimal treatment strategies are scarce. We report on 11 consecutively treated children with centrally confirmed diagnosis of CNS ependymoblastoma, registered between February 1994 and October 2006 to the prospective GPOH-HIT multicenter brain tumor trials, and treated by multimodal regimens. Median age at diagnosis was 3.5 years (range, 1.8-5.6 years), and the median follow-up of survivors was 5.9 years (range, 2.2-12.7 years). Initial stage was M0 in 9, and M0/1 (no cerebrospinal fluid examination done) in 2 patients. Gross-total tumor resection was achieved in 7 patients, incomplete resection in 4 patients. Further primary therapy included chemotherapy in all patients, craniospinal radiotherapy in 5 patients and high-dose chemotherapy in 2 patients. Tumor response to chemotherapy was observed in 1 of 4 evaluable patients. Tumor progression occurred in 7 patients after a median time of 5.0 months (range, 2.5-19.2 months). Five-year progression-free survival was 36.4% (±14.5%), 5-year overall survival 30.3% (±15.9%). Of 4 survivors, 3 had gross-total tumor resection, and all were treated by either craniospinal radiotherapy and/or high-dose chemotherapy with autologous blood stem cell rescue. Prognosis of children with ependymoblastoma is poor, but sustained remissions have been achieved after multimodal treatment. Considerable diagnostic discrepancies between local and central pathologists underscore the importance of central review. Further studies are needed to improve survival of children with this rare malignant central nervous system tumor. [ABSTRACT FROM AUTHOR]

The article presents a study related to the evidence of Histone 3 (H3) K27M mutations in diffuse midline gliomas, including high-grade astrocytomas and diffuse intrinsic pontine gliomas (DIPG). It mentions that these mutations are associated with alterations in the epigenetic profile of tumor cells. It states that despite of the presence of H3K27M mutation as detected by immunohistochemistry or sequencing remains a strong argument for the diagnosis of a diffuse midline glioma.

A letter to the editor on medulloblastoma (MB) in malignant pediatric brain tumors is presented.