Search

Purpose: Malignant intracranial germ cell tumors (GCTs) are rare diseases in Western countries. They arise in midline structures and diagnosis is often delayed. We evaluated imaging characteristics and early tumor signs of suprasellar and bifocal GCT on MRI. Methods: Patients with the diagnosis of a germinoma or non-germinomatous GCT (NGGCT) who received non-contrast sagittal T1WI on MRI pre-therapy were included. Loss of the posterior pituitary bright spot (PPBS), the expansion and size of the tumor, and the expansion and infiltration of surrounding structures were evaluated. Group comparison for histologies and localizations was performed. Results: A total of 102 GCT patients (median age at diagnosis 12.3 years, range 4.4–33.8; 57 males; 67 in suprasellar localization) were enrolled in the study. In the suprasellar cohort, NGGCTs (n = 20) were noticeably larger than germinomas (n = 47; p <.001). Each tumor showed involvement of the posterior lobe or pituitary stalk. A PPBS loss (total n = 98) was observed for each localization and entity in more than 90% and was related to diabetes insipidus. Osseous infiltration was observed exclusively in suprasellar GCT (significantly more frequent in NGGCT; p =.004). Time between the first MRI and therapy start was significantly longer in the suprasellar cohort (p =.005), with an even greater delay in germinoma compared to NGGCT (p =.002). The longest interval to treatment had circumscribed suprasellar germinomas (median 312 days). Conclusion: A loss of the PPBS is a hint of tumor origin revealing small tumors in the neurohypophysis. Using this sign in children with diabetes insipidus avoids a delay in diagnosis. [ABSTRACT FROM AUTHOR]

Introduction: Neurosurgery is considered the mainstay of treatment for pediatric low‐grade glioma (LGG); the extent of resection determines subsequent stratification in current treatment protocols. Yet, surgical radicality must be balanced against the risks of complications that may affect long‐term quality of life. We investigated whether this consideration impacted surgical resection patterns over time for patients of the German LGG studies. Patients and Methods: Four thousand two hundred and seventy pediatric patients from three successive LGG studies (median age at diagnosis 7.6 years, neurofibromatosis (NF1) 14.7%) were grouped into 5 consecutive time intervals (TI1‐5) for date of diagnosis and analyzed for timing and extent of first surgery with respect to tumor site, histology, NF1‐status, sex, and age. Results: The fraction of radiological LGG diagnoses increased over time (TI1 12.6%; TI5 21.7%), while the extent of the first neurosurgical intervention (3440/4270) showed a reduced fraction of complete/subtotal and an increase of partial resections from TI1 to TI5. Binary logistic regression analysis for the first intervention within the first year following diagnosis confirmed the temporal trends (p < 0.001) and the link with tumor site for each extent of resection (p < 0.001). Higher age is related to more complete resections in the cerebellum and cerebral hemispheres. Conclusions: The declining extent of surgical resections over time was unrelated to patient characteristics. It paralleled the evolution of comprehensive treatment algorithms; thus, it may reflect alignment of surgical practice to recommendations in respect to age, tumor site, and NF1‐status integrated as such into current treatment guidelines. Further investigations are needed to understand how planning, performance, or tumor characteristics impact achieving surgical goals. [ABSTRACT FROM AUTHOR]

Simple Summary: The treatment options for children with recurrent medulloblastoma are often limited due to extensive previously received treatments after initial diagnosis. Especially, repeated radiotherapy is associated with significant side-effects. In this study, we study the impact on survival of repeated radiotherapy at recurrence for patients with previous irradiation, as well as first irradiation at recurrence when no previous radiotherapy was applied. We find that repeated radiotherapy provides a short-time benefit in terms of survival, but survival ten years after recurrence is not significantly improved. At the same time, we find that applying radiotherapy at recurrence when patients received no previous irradiation did significantly improve survival, both short and long term. Background: Radiotherapy (RT) involving craniospinal irradiation (CSI) is important in the initial treatment of medulloblastoma. At recurrence, the re-irradiation options are limited and associated with severe side-effects. Methods: For pre-irradiated patients, patients with re-irradiation (RT2) were matched by sex, histology, time to recurrence, disease status and treatment at recurrence to patients without RT2. Results: A total of 42 pre-irradiated patients with RT2 were matched to 42 pre-irradiated controls without RT2. RT2 improved the median PFS [21.0 (CI: 15.7–28.7) vs. 12.0 (CI: 8.1–21.0) months] and OS [31.5 (CI: 27.6–64.8) vs. 20.0 (CI: 14.0–36.7) months]. Concerning long-term survival after ten years, RT2 only lead to small improvements in OS [8% (CI: 1.4–45.3) vs. 0%]. RT2 improved survival most without (re)-resection [PFS: 17.5 (CI: 9.7–41.5) vs. 8.0 (CI: 6.6–12.2)/OS: 31.5 (CI: 27.6–NA) vs. 13.3 (CI: 8.1–20.1) months]. In the RT-naïve patients, CSI at recurrence improved their median PFS [25.0 (CI: 16.8–60.6) vs. 6.6 (CI: 1.5–NA) months] and OS [40.2 (CI: 18.7–NA) vs. 12.4 (CI: 4.4–NA) months]. Conclusions: RT2 could improve the median survival in a matched cohort but offered little benefit regarding long-term survival. In RT-naïve patients, CSI greatly improved their median and long-term survival. [ABSTRACT FROM AUTHOR]

This study aimed to re-evaluate the prognostic impact of TP53 mutations and to identify specific chromosomal aberrations as possible prognostic markers in WNT-activated medulloblastoma (WNT-MB). In a cohort of 191 patients with WNT-MBs, mutations in CTNNB1, APC, and TP53 were analyzed by DNA sequencing. Chromosomal copy-number aberrations were assessed by molecular inversion probe technology (MIP), SNP6, or 850k methylation array hybridization. Prognostic impact was evaluated in 120 patients with follow-up data from the HIT2000 medulloblastoma trial or HIT registries. CTNNB1 mutations were present in 92.2%, and APC mutations in 6.8% of samples. One CTNNB1 wild-type tumor gained WNT activation due to homozygous FBXW7 deletion. Monosomy 6 was present in 78.6%, and more frequent in children than adults. 16.1% of tumor samples showed TP53 mutations, of those 60% with nuclear positivity for the p53 protein. Loss of heterozygosity at the TP53 locus (chromosome 17p13.1) was found in 40.7% (11/27) of TP53 mutant tumor samples and in 12.6% of TP53 wild-type cases (13/103). Patients with tumors harboring TP53 mutations showed significant worse progression-free survival (PFS; 5-year-PFS 68% versus 93%, p = 0.001), and were enriched for chromosomes 17p (p = 0.001), 10, and 13 losses. Gains of OTX2 (14q22.3) occurred in 38.9% of samples and were associated with poor PFS and OS (5-year-PFS 72% versus 93%, p = 0.017 resp. 5-year-OS 83% versus 97%, p = 0.006). Multivariable Cox regression analysis for PFS/OS identified both genetic alterations as independent prognostic markers. Our data suggest that patients with WNT-MB carrying TP53 mutations or OTX2 gains (58.1%) are at higher risk of relapse. Eligibility of these patients for therapy de-escalation trials needs to be debated. [ABSTRACT FROM AUTHOR]

Rhabdoid tumors (RT) are rare and highly aggressive pediatric neoplasms. Their epigenetically-driven intertumoral heterogeneity is well described; however, the cellular origin of RT remains an enigma. Here, we establish and characterize different genetically engineered mouse models driven under the control of distinct promoters and being active in early progenitor cell types with diverse embryonic onsets. From all models only Sox2-positive progenitor cells give rise to murine RT. Using single-cell analyses, we identify distinct cells of origin for the SHH and MYC subgroups of RT, rooting in early stages of embryogenesis. Intra- and extracranial MYC tumors harbor common genetic programs and potentially originate from fetal primordial germ cells (PGCs). Using PGC specific Smarcb1 knockout mouse models we validate that MYC RT originate from these progenitor cells. We uncover an epigenetic imbalance in MYC tumors compared to PGCs being sustained by epigenetically-driven subpopulations. Importantly, treatments with the DNA demethylating agent decitabine successfully impair tumor growth in vitro and in vivo. In summary, our work sheds light on the origin of RT and supports the clinical relevance of DNA methyltransferase inhibitors against this disease. Rhabdoid tumors (RT) are aggressive paediatric cancers with yet unknown cells of origin. Here, the authors establish genetically engineered mouse models of RT and, using single-cell RNA-seq and epigenomics, identify potential cells of origin for the SHH and MYC subtypes. [ABSTRACT FROM AUTHOR]

Gorlin syndrome is a genetic condition associated with the occurrence of SHH activated medulloblastoma, basal cell carcinoma, macrocephaly and other congenital anomalies. It is caused by heterozygous pathogenic variants in PTCH1 or SUFU. In this study we included 16 patients from the HIT2000, HIT2000interim, I-HIT-MED, observation registry and older registries such as HIT-SKK87, HIT-SKK92 (1987 – 2020) with genetically confirmed Gorlin syndrome, harboring 10 PTCH1 and 6 SUFU mutations. Nine patients presented with desmoplastic medulloblastomas (DMB), 6 with medulloblastomas with extensive nodularity (MBEN) and one patient with classic medulloblastoma (CMB); all tumors affected the cerebellum, vermis or the fourth ventricle. SHH activation was present in all investigated tumors (14/16); DNA methylation analysis (when available) classified 3 tumors as iSHH-I and 4 tumors as iSHH-II. Age at diagnosis ranged from 0.65 to 3.41 years. All but one patient received chemotherapy according to the HIT-SKK protocol. Ten patients were in complete remission after completion of primary therapy; four subsequently presented with PD. No patient received radiotherapy during initial treatment. Five patients acquired additional neoplasms, namely basal cell carcinomas, odontogenic tumors, ovarian fibromas and meningioma. Developmental delay was documented in 5/16 patients. Overall survival (OS) and progression-free survival (PFS) between patients with PTCH1 or SUFU mutations did not differ statistically (10y-OS 90% vs. 100%, p=0.414; 5y-PFS 88.9% ± 10.5% vs. 41.7% ± 22.2%, p=0.139). Comparing the Gorlin patients to all young, SHH activated MBs in the registries (10y-OS 93.3% ± 6.4% vs. 92.5% ± 3.3%, p=0.738; 10y-PFS 64.9%+-16.7% vs. 83.8%+-4.5%, p=0.228) as well as comparing Gorlin M0 SKK-treated patients to all young, SHH activated, M0, SKK-treated MBs in the HIT-MED database did not reveal significantly different clinical outcomes (10y-OS 88.9% ± 10.5% vs. 88% ± 4%, p=0.812; 5y-PFS 87.5% ± 11.7% vs. 77.7% ± 5.1%, p=0.746). Gorlin syndrome should be considered in young children with SHH activated medulloblastoma, especially DMB and MBEN but cannot be ruled out for CMB. Survival did not differ to patients with SHH-activated medulloblastoma with unknown germline status or between PTCH1 and SUFU mutated patients. Additional neoplasms, especially basal cell carcinomas, need to be expected and screened for. Genetic counselling should be provided for families with young medulloblastoma patients with SHH activation. [ABSTRACT FROM AUTHOR]

Purpose: Survival in recurrent ependymoma (EPN) depends mainly on the extent of resection achieved. When complete resection is not feasible, chemotherapy is often used to extend progression-free and overall survival. However, no consistent effect of chemotherapy on survival has been found in patients with recurrent EPN. Methods: Systemic chemotherapeutic treatment of 138 patients enrolled in the German HIT-REZ-studies was analyzed. Survival depending on the use of chemotherapy, disease-stabilization rates (RR), duration of response (DOR) and time to progression (TTP) were estimated. Results: Median age at first recurrence was 7.6 years (IQR: 4.0–13.6). At first recurrence, median PFS and OS were 15.3 (CI 13.3–20.0) and 36.9 months (CI 29.7–53.4), respectively. The Hazard Ratio for the use of chemotherapy in local recurrences in a time-dependent Cox-regression analysis was 0.99 (CI 0.74–1.33). Evaluable responses for 140 applied chemotherapies were analyzed, of which sirolimus showed the best RR (50%) and longest median TTP [11.51 (CI 3.98; 14.0) months] in nine patients, with the strongest impact found when sirolimus was used as a monotherapy. Seven patients with progression-free survival > 12 months after subtotal/no-resection facilitated by chemotherapy were found. No definitive survival advantage for any drug in a specific molecularly defined EPN type was found. Conclusion: No survival advantage for the general use of chemotherapy in recurrent EPN was found. In cases with incomplete resection, chemotherapy was able to extend survival in individual cases. Sirolimus showed the best RR, DOR and TTP out of all drugs analyzed and may warrant further investigation. [ABSTRACT FROM AUTHOR]

Introduction: Standardisation of imaging acquisition is essential in facilitating multicentre studies related to childhood CNS tumours. It is important to ensure that the imaging protocol can be adopted by centres with varying imaging capabilities without compromising image quality. Materials and method: An imaging protocol has been developed by the Brain Tumour Imaging Working Group of the European Society for Paediatric Oncology (SIOPE) based on consensus among its members, which consists of neuroradiologists, imaging scientists and paediatric neuro-oncologists. This protocol has been developed to facilitate SIOPE led studies and regularly reviewed by the imaging working group. Results: The protocol consists of essential MRI sequences with imaging parameters for 1.5 and 3 Tesla MRI scanners and a set of optional sequences that can be used in appropriate clinical settings. The protocol also provides guidelines for early post-operative imaging and surveillance imaging. The complementary use of multimodal advanced MRI including diffusion tensor imaging (DTI), MR spectroscopy and perfusion imaging is encouraged, and optional guidance is provided in this publication. Conclusion: The SIOPE brain tumour imaging protocol will enable consistent imaging across multiple centres involved in paediatric CNS tumour studies. [ABSTRACT FROM AUTHOR]

First‐line treatment of pediatric low‐grade glioma using surgery, radio‐ or chemotherapy fails in a relevant proportion of patients. We analyzed efficacy of subsequent surgical and nonsurgical therapies of the German cohort of the SIOP‐LGG 2004 study (2004‐2012, 1558 registered patients; median age at diagnosis 7.6 years, median observation time 9.2 years, overall survival 98%/96% at 5/10 years, 15% neurofibromatosis type 1 [NF1]). During follow‐up, 1078/1558 patients remained observed without (n = 217), with 1 (n = 707), 2 (n = 124) or 3 to 6 (n = 30) tumor volume reductions; 480/1558 had 1 (n = 332), 2 (n = 80), 3 or more (n = 68) nonsurgical treatment‐lines, accompanied by up to 4 tumor‐reductive surgeries in 215/480; 265/480 patients never underwent any neurosurgical tumor volume reduction (163/265 optic pathway glioma). Patients with progressing tumors after first‐line adjuvant treatment were at increased risk of suffering further progressions. Risk factors were young age (<1 year) at start of treatment, tumor dissemination or progression within 18 months after start of chemotherapy. Progression‐free survival rates declined with subsequent treatment‐lines, yet remaining higher for patients with NF1. In non‐NF1‐associated tumors, vinblastine monotherapy vs platinum‐based chemotherapy was noticeably less effective when used as second‐line treatment. Yet, for the entire cohort, results did not favor a certain sequence of specific treatment options. Rather, all can be aligned as a portfolio of choices which need careful balancing of risks and benefits. Future molecular data may predict long‐term tumor biology. What's new? For some patients with pediatric low‐grade glioma, first‐line treatment isn't enough. Here, the authors evaluated the effectiveness of various second‐line strategies, including surgical and non‐surgical therapies, in a German cohort. Risk factors for tumor progression included age under 1 year at diagnosis, early treatment failure, and tumor dissemination. Over the entire cohort, the results did not clearly support one specific treatment strategy as the best choice, although platinum‐based therapy performed better than vinblastine in non‐NF1 tumors. This is the first long term analysis of comprehensive treatment strategies in recurrent tumors in a population‐based, prospectively registered pediatric low‐grade glioma cohort. [ABSTRACT FROM AUTHOR]

Reports on pediatric low‐grade diffuse glioma WHO‐grade II (DG2) suggest an impaired survival rate, but lack conclusive results for genetically defined DG2‐entities. We analyzed the natural history, treatment and prognosis of DG2 and investigated which genetically defined sub‐entities proved unfavorable for survival. Within the prospectively registered, population‐based German/Swiss SIOP‐LGG 2004 cohort 100 patients (age 0.8‐17.8 years, 4% neurofibromatosis [NF1]) were diagnosed with a DG2. Following biopsy (41%) or variable extent of resection (59%), 65 patients received no adjuvant treatment. Radiologic progression or severe neurologic symptoms prompted chemotherapy (n = 18) or radiotherapy (n = 17). Multiple lines of salvage treatment were necessary for 19/35 patients. Five years event‐free survival dropped to 0.44, while 5 years overall survival was 0.90 (median observation time 8.3 years). Extensive genetic profiling of 65/100 DG2 identified Histone3‐K27M‐mutation in 4, IDH1‐mutation in 11, BRAF‐V600‐mutation in 12, KIAA1549‐BRAF‐fusions in 6 patients, while the remaining 32 tumor tissues did not show alterations of these genes. Progression to malignant glioma occurred in 12 cases of all genetically defined subgroups within a range of 0.5 to 10.8 years, except for tumors carrying KIAA1549‐BRAF‐fusions. Histone3‐K27M‐mutant tumors proved uniformly fatal within 0.6 to 2.4 years. The current LGG treatment strategy seems appropriate for all DG2‐entities, with the exemption of Histone3‐K27M‐mutant tumors that require a HGG‐related treatment strategy. Our data confirm the importance to genetically define pediatric low‐grade diffuse gliomas for proper treatment decisions and risk assessment. What's new? Pediatric low‐grade diffuse gliomas histologically resemble their adult counterparts, but they differ greatly in terms of genetics, clinical behavior, and prognosis. Here, the authors investigated genetic mutations in 65 pediatric grade 2 diffuse gliomas (DG2), looking for a correlation with long‐term outcome. All 4 tumors carrying the K27M mutation in the Histone3 gene were fatal. Conversely, none of the 6 tumors carrying a particular duplication of the BRAF gene, called the KIAA1549‐BRAF fusion, progressed to malignant glioma. The authors characterized the tumor genetics with respect to prognosis, age at onset, and response to treatment. [ABSTRACT FROM AUTHOR]

Reports on pediatric low‐grade glioma (LGG) of the caudal brainstem are retrospective with heterogeneous cohorts, variable treatments and inconsistent outcome data. We analyzed their natural history and asked whether brainstem location proved unfavorable for survival within the framework of the comprehensive SIOP‐LGG 2004 management strategy. Within the prospectively registered, population‐based German SIOP‐LGG 2004 cohort 116 patients (age 0.2–16.5 years, 10% Neurofibromatosis NF1) were diagnosed with LGG of the pons (27%) and medulla oblongata (73%). After biopsy (23%), variable resection (63%) or radiologic diagnosis only (14%), 59 patients received no adjuvant treatment. Radiologic progression or severe neurologic symptoms prompted chemo‐ (n = 39) or radiotherapy (n = 18). After further progression (28/57), salvage treatments included multiple treatment lines for 12/28 patients. Five‐years event‐free survival dropped to 0.40, while 5‐years overall survival was 0.95 (median observation time 6.8 years). Higher extent of resection yielded lower progression rate (p = 0.001), but at a cost of 21/100 patients suffering from new postsurgical complications including respiratory insufficiency. Central review confirmed pilocytic astrocytoma (56%), diffuse astrocytoma (8%) or glioneuronal histology (16%) (others 4%, no histology 17%). Malignant evolution was documented in five patients associated with Histone3 mutation in 2/5. Our treatment algorithm conveyed high overall survival for pediatric brainstem LGG. Extensive neurosurgical resection did increase additional postoperative neurologic deficits but not overall survival in this often‐chronic disease. More than half of all patients can be safely followed by observation, while multimodal adjuvant treatment can control progressive tumors. Molecular assessment should confirm low‐grade diagnosis and may detect patterns prognostic for malignant evolution. What's new? Outcome studies for pediatric low‐grade gliomas (LGG) of the brainstem have generally been small and of low quality, making it difficult to determine prognosis. In this prospective, multicenter study, the authors developed a detailed description of the natural history, treatment response, and prognostic factors associated with favorable survival when a comprehensive treatment strategy was used. This treatment algorithm resulted in high overall survival for pediatric brainstem LGG. The study also emphasizes the importance of the predictive value of molecular patterns, as malignant evolution can occur even in low‐grade tumors. [ABSTRACT FROM AUTHOR]

Purpose: The diagnosis of diffuse intrinsic pontine glioma (DIPG) is based largely on a combination of clinical and radiological findings due to the difficulty of obtaining a biopsy. An accurate evaluation of magnetic resonance imaging (MRI) scans is consequently essential. Recent analyses on the genomic landscape of DIPG revealed recurrent mutations in the H3F3A and HIST1H3B histone genes. We reviewed cases with available tumor tissue from institutional DIPG series to ascertain the consistency between their histo-molecular findings and clinical-radiological features. Methods: We conducted a radiological and pathological central review of 22 cases enrolled in institutional DIPG trials. We performed immunohistochemical analyses to detect H3F3A/HIST1H3B K27M mutations, histone trimethylation, and EZH2 expression. Mutational analysis was performed for ACVR1, H3F3A, and HIST1H3B genes. Results: Patients' median age at diagnosis was 8 years, and their median overall survival was 11 months. Nineteen/22 cases (86%) showed evidence of K27M mutation on immunohistochemistry and/or mutation analysis. Histone trimethylation expression was low or lacking in these mutated cases. Sequence analysis revealed 13 cases with H3F3A and 1 case with HIST1H3B K27M mutation. There was no significant difference in EZH2 expression between the K27M mutant and wild-type DIPGs. Upon external, blinded MRI re-evaluation one lesion not consistent with DIPG showed no evidence of K27M mutation and retained histone trimethylation expression. Conclusion: In conclusion, our study demonstrates a high frequency of histone K27M mutations in DIPG when MRI features are carefully assessed, thus confirming the consistency of imaging with biological markers in our institutional series of DIPG. [ABSTRACT FROM AUTHOR]

Young children with brain tumours are at high risk of developing treatment-related sequelae. We aimed to assess neuropsychological outcomes 5 years after treatment. This cross-sectional study included children under 4 years of age with medulloblastoma (MB) or ependymoma (EP) enrolled in the German brain tumour trials HIT2000 and HIT-REZ2005. Testing was performed using the validated Wuerzburg Intelligence Diagnostics (WUEP-D), which includes Kaufman-Assessment-Battery, Coloured Progressive Matrices, Visual-Motor Integration, finger tapping "Speed", and the Continuous Performance Test. Of 104 patients in 47 centres, 72 were eligible for analyses. We assessed whether IQ was impacted by disease extent, disease location, patient age, gender, age at surgery, and treatment (chemotherapy with our without craniospinal irradiation [CSI] or local radiotherapy [LRT]). Median age at surgery was 2.3 years. Testing was performed at a median of 4.9 years after surgery. Patients with infratentorial EPs (treated with LRT) scored highest in fluid intelligence (CPM 100.9±16.9, mean±SD); second best scores were achieved by patients with MB without metastasis treated with chemotherapy alone (CPM 93.9±13.2), followed by patients with supratentorial EPs treated with LRT. In contrast, lowest scores were achieved by patients that received chemotherapy and CSI, which included children with metastasised MB and those with relapsed MB M0 (CPM 71.7±8.0 and 73.2±21.8, respectively). Fine motor skills were reduced in all groups. Multivariable analysis revealed that type of treatment had an impact on IQ, but essentially not age at surgery, time since surgery or gender. Our results confirm previous reports on the detrimental effects of CSI in a larger cohort of children. Comparable IQ scores in children with MB treated only with chemotherapy and in children with EP suggest that this treatment strategy represents an attractive option for children who have a high chance to avoid application of CSI. Longitudinal follow-up examinations are warranted to assess long-term neuropsychological outcomes. [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]

Background: Data on frequency, clinical presentation, and outcome of primary metastatic intracranial ependymoma in children are scarce. Patients and Methods: Prospective data on patients younger than 21 years with metastatic intracranial ependymoma at first diagnosis, registered from 2001 to 2014 in the HIT‐2000 trial and the HIT‐2000 Interim Registry, were analyzed. Results: Of 453 registered patients with intracranial ependymoma and central neuropathology review, initial staging included spinal magnetic resonance imaging in all patients and lumbar cerebrospinal fluid (CSF) analysis in 402 patients. Ten patients (2.2%) had metastatic disease, including three with microscopic CSF positivity only (M1 metastasis stage, 0.7% of patients with CSF staging). Location of the primary tumor was supratentorial in four patients (all supratentorial RELA‐fused ependymoma [ST‐EPN‐RELA]) and within the posterior fossa in five patients (posterior fossa ependymoma type A [PF‐EPN‐A], n = 4; posterior fossa ependymoma not further classifiable, n = 1), and multifocal in one patient. All four patients with ST‐EPN‐RELA were alive in first or second complete remission (CR) 7.5–12.3 years after diagnosis. All four patients with macroscopic metastases of posterior fossa or multifocal ependymoma died. Three patients with initial M1 stage (ST‐EPN‐RELA, n = 1; PF‐EPN‐A, n = 2) received chemotherapy and local irradiation and were alive in second or third CR 3.0–9.7 years after diagnosis. Progression‐free and overall survival of the entire cohort at 5 years was 13% (±6%), and 58% (±16%), respectively. Conclusion: Primary metastatic disease is rare in children with intracranial ependymoma. Prognosis may depend on molecular subgroup and extent of dissemination, and relevance of CSF analysis for initial staging remains to be clarified. Implications for Practice: Childhood ependymoma presenting with metastasis at first diagnosis is very rare with a frequency of 2.4% in this population‐based, well‐characterized cohort. Detection of microscopic metastases in the cerebrospinal fluid was extremely rare, and impact on prognosis and respective treatment decision on irradiation field remains unclear. Initial metastatic presentation occurs in both supratentorial RELA‐fused ependymoma and posterior fossa ependymoma. Prognosis may differ according to extent of metastasis and biological subgroup, with poor prognosis in diffusely spread metastatic posterior fossa ependymoma even after combination therapy with both intensive chemotherapy and craniospinal irradiation, which may help to guide individual therapeutic decisions for future patients. Ependymoma is the second most frequent malignant central nervous system neoplasm in children and adolescents. Data on frequency, clinical presentation, and outcome of primary metastatic intracranial ependymoma are scarce. This study analyzed the frequency, molecular diagnosis, clinical presentation, and outcome of patients diagnosed with primary metastatic ependymoma and registered in the HIT series. [ABSTRACT FROM AUTHOR]

Background: Craniopharyngioma is a tumor of low histological malignancy resulting from an anomaly of embryonic development. Affected children and adolescents are being studied with respect to their quality of life, progression-free survival, and overall survival in the framework of the ongoing KRANIOPHARYNGEOM 2007 project. Methods: This prospective, multicenter project consists of a randomized trial with an adaptive design combined with a purely observational study. The randomized, unblinded trial includes patients whose tumors have been incompletely resected and is intended to compare the outcomes of immediate postoperative radiotherapy versus radiotherapy on progression. Its primary endpoint is quality of life as assessed subjectively by the patients themselves with the "Pediatric Quality of Life" questionnaire (PEDQOL). In exploratory analyses, linear mixed models were used to study the effect of further factors on quality of life. Results: An interim intention-to-treat analysis of the randomized trial revealed only minor differences between the treatment arms with respect to quality of life (n = 24). The exploratory analyses (n = 131) showed that preoperative involvement of, or operative damage to, the anterior and posterior regions of the hypothalamus was associated with a lower quality of life. Complete resection was followed by a lower quality of life than incomplete resection. Radiotherapy, a common treatment for tumors that progress after incomplete resection, was also associated with a lower quality of life. Conclusion: Hypothalamus-sparing treatment approaches are recommended to optimize the quality of life of children and adolescents with craniopharyngioma. The available evidence does not support any recommendation as to when radiotherapy should be performed after incomplete resection so that the best quality of life can be achieved. [ABSTRACT FROM AUTHOR]

BACKGROUND: Tectal plate low-grade gliomas (LGGs) most often present with increased intracranial pressure and sometimes as incidental findings from brain imaging. Prognostic factors predicting outcome are largely unknown. METHODS: From 2004 until 2012, 71 patients with tectal plate LGG from Germany and Switzerland were followed within the SIOP-LGG 2004 study. Median age at diagnosis was 9.7 (range: 0.1-17.5) years, and median follow-up time of surviving patients was 6.3 (interquartile range: 4.9-8.3) years. RESULTS: A total of 41 out of 71 patients received no tumor treatment (12 with and 29 without biopsy). The 10-year event-free survival (EFS) rate (± standard error ) for patients with an initial tumor volume of ≤3 cm3 was 56% (±7%), as opposed to 12% (±8%) for those with tumors >3 cm3 (p < 0.001). The 10-year EFS for patients without contrast enhancement on initial magnetic resonance imaging (MRI) was 52% (±9%), and for those with enhancement, it was 23% (±9%) (p = 0.003). The 10-year overall survival rate was 96% (±3%) (death due to disease, 1; ventriculoperitoneal shunt infection, 1). Sixty-three (89%) patients had at least one cerebrospinal fluid diversion procedure. CONCLUSIONS: More than half of patients were managed without tumor treatment. Favorable prognostic factors for EFS were small initial tumor volume (≤3cm3) and the absence of initial contrast enhancement on MRI. Overall survival was excellent. [ABSTRACT FROM AUTHOR]

Background: Assessment of presurgical hypothalamic involvement (psHI) and treatment-related hypothalamic damage (trHD) is relevant for the decision on risk-adapted treatment and rehabilitation strategies in craniopharyngioma.Patients and methods: 129 surgical reports of childhood-onset craniopharyngioma patients recruited 2007-2014 in KRANIOPHARYNGEOM 2007 were analyzed. Data on psHI were available based on surgeon’s (63%), reference neuroradiologist’s (95%), and local radiologist’s (23%) assessment. The surgical degree of resection (DoR) was assessed by neurosurgeon (95%), reference neuroradiologist (73%), and local radiologist (61%). TrHD was assessed by neurosurgeon (33%), by reference neuroradiologist (95%), and by local radiologist (2%). Neurosurgical center size was categorized based on patient load.Results: Surgical assessments on psHI (n = 78), DoR (n = 89) and trHD (n = 42) as documented in surgical reports could be compared with the assessment of respective parameters by reference neuroradiologist. Differences with regard to DoR (p = 0.0001) and trHD (p < 0.0001) were detectable between surgeon’s and reference neuroradiologist’s assessment, whereas psHI was assessed similarly. Concordance for DoR and trHD was observed in 48 and 62%, respectively. Surgeons estimated a higher rate of complete resections and a lower rate of trHD. Neuroradiological reference assessment of trHD had higher predictive value for hypothalamic sequelae then surgical assessment. Observed differences were not related to neurosurgical center size.Conclusions: Observed differences between surgical and neuroradiological estimation of risk factors in craniopharyngioma support the necessity of neuroradiological reference review to assure standards of quality. This could be established by central internet-based neuroradiological review in KRANIOPHARYNGEOM 2007. Standardization of surgical reports including specific assessment of tumor/damage location is recommended. [ABSTRACT FROM AUTHOR]

Purpose: As the efficacy of all pediatric high-grade glioma (HGG) treatments is similar and still disappointing, it is essential to also investigate the toxicity of available treatments.Methods: Prospectively recorded hematologic and nonhematologic toxicities of children treated with radiochemotherapy in the HIT GBM-C/D and HIT-HGG-2007 trials were compared. Children aged 3-18 years with histologically proven HGG (WHO grade III and IV tumors) or unequivocal radiologic diagnosis of diffuse intrinsic pontine glioma (DIPG) were included in these trials. The HIT-HGG-2007 protocol comprised concomitant radiochemotherapy with temozolomide, while cisplatinum/etoposide (PE) and PE plus ifosfamide (PEI) in combination with weekly vincristine injections were applied during radiochemotherapy in the HIT GBM-C/D protocol.Results: Regular blood counts and information about cellular nadirs were available from 304 patients (leukocytes) and 306 patients (thrombocytes), respectively. Grade 3-4 leukopenia was much more frequent in the HIT GBM-C/D cohort (n = 88, 52%) vs. HIT-HGG-2007 (n = 13, 10%; P <0.001). Grade 3-4 thrombopenia was also more likely in the HIT GBM-C/D cohort (n = 21, 12% vs. n = 3,2%; P <0.001). Grade 3-4 leukopenia appeared more often in children aged 3-7 years (n = 38/85, 45%) than in children aged 8-12 years (n = 39/120, 33%) and 13-18 years (24/100, 24%; P =0.034). In addition, sickness was more frequent in the HIT GBM-C/D cohort (grade 1-2: 44%, grade 3-4: 6% vs. grade 1-2: 28%, grade 3-4: 1%; P <0.001).Conclusion: Radiochemotherapy involving cisplatinum-based polychemotherapy is more toxic than radiotherapy in combination with temozolomide. Without evidence of differences in therapeutic efficacy, the treatment with lower toxicity, i. e., radiotherapy with temozolomide should be used. [ABSTRACT FROM AUTHOR]

Context: Quality of life (QoL) after childhood-onset craniopharyngioma (CP) is frequently impaired due to tumor and/or treatment-related factors such as endocrine deficits and hypothalamic involvement/lesions.Patients and methods: In a multinational trial, we prospectively analyzed parental and self-assessment of CP patient QoL at 3 months, 1 and 3 years after CP diagnosis related to growth hormone (GH) substitution. 47 of 194 CP recruited between 2007 and 2015 in KRANIOPHARYNGEOM 2007 were analyzed for QoL 1 and 3 years after CP diagnosis. QoL was assessed by Pediatric Quality of Life (PEDQOL) questionnaire and PEDQOL scores of parental and self-assessed QoL during 3 years follow-up after CP diagnosis were analyzed.Results: Parents estimated QoL of their children worse than patients did themselves. GH substitution had no relevant effect on short-term weight and height development. CP patients GH-treated at 3 years follow-up presented at baseline (1 year after diagnosis, before GH substitution) with reduced self-assessed QoL when compared with GH non-treated CP. QoL stabilized during 1–3 years of follow-up in GH-treated patients, whereas non GH-treated patients experienced decreases in autonomy (p = 0.03), cognition (p = 0.01), and physical function (p = 0.04).Conclusions: Parents assess QoL in CP survivors worse than their children. GH substitution should be considered as a therapeutic option to ameliorate imminent impairments of QoL after CP. [ABSTRACT FROM AUTHOR]

Purpose: High messenger RNA (mRNA) expression of the tropomyosin receptor kinase C gene ( TrkC) has been associated with favorable survival in medulloblastoma patients. Untested is whether it plays a role through modulating the response to therapy or whether it might be a surrogate marker for a favorable molecular subgroup. Methods: The medulloblastoma-derived cell line DAOY was stably transfected to overexpress TrkC (clone DAOY-TrkC) and compared to a control (clone DAOY-EV, empty vector transfected). Cell viability (MTS assay) was tested after irradiation or incubation with chemotherapeutic drugs. Neuroradiologic response to postoperative chemotherapy or craniospinal irradiation (CSI) of medulloblastoma patients aged 3-21 years with postoperative residual disease treated within the consecutive trials HIT'91/HIT2000 was compared to TrkC mRNA expression in their tumor samples. Five well-characterized independent expression-profiling studies covering together 686 medulloblastoma patients were analyzed for TrkC levels according to the molecular subgroups. Results: Cell viability of DAOY-TrkC compared to DAOY-EV was not different after exposure to increasing doses of irradiation, cisplatin, etoposide, or vincristine. While TrkC mRNA expression tended to be higher in non-responders ( n = 5/19) to postoperative CSI ( p = 0.03, ratio 15.5, 95% CI 9-267), this was the case in responders ( n = 23/43) to chemotherapy ( p = 0.04, ratio 6.1, 95% CI 1.1-35), both analyzed with Mann-Whitney U test (not significant after Bonferroni adjustment). The highest TrkC mRNA levels were found in the SHH subgroup across all expression-profiling studies. Conclusions: High TrkC mRNA expression appears to be frequent in the SHH subgroup and seems not to have a major effect on therapy responsiveness in medulloblastoma patients. [ABSTRACT FROM AUTHOR]

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

Background. Thalamic low-grade glioma (LGG) poses a special therapeutic challenge, as complete resection is often not possible. To determine the survival outcomes of mono- and bithalamic LGG, we analyzed a large cohort of pediatric patients. Methods. From 1996 until 2012, 2618 patients were registered in the HIT-LGG 1996 and the SIOP-LGG 2004 studies. A total of 102 of these 2618 patients (3.9%) were diagnosed with a thalamic LGG with a median age at diagnosis of 8.0 years (range, 0.4-17.5 years); 87 patients (85%) had monothalamic and 15 patients (15%) had bithalamic LGG. Results. Ninety patients received at least one surgical procedure. Thirty-one patients received radiotherapy and 24 patients received chemotherapy as a first-line, nonsurgical treatment indicated by radiological tumor progression or severe/progressive clinical symptoms. Patients with monothalamic tumors showed a 10-year overall survival (OS) rate of 91%, whereas patients with bithalamic tumors only reached 65% (P = .001). Bithalamic tumors more frequently showed diffuse histology than monothalamic tumors. Patients with diffuse astrocytoma had a lower 10-year OS (68%) than those with pilocytic astrocytoma (93%). The 10-year progression-free survival rate after the start of first nonsurgical treatment was 53% in the radiotherapy group and 34% in the chemotherapy group. Conclusions. Thalamic glioma was manageable using a strategy that included surgery, observation, chemotherapy, and/or radiotherapy. Radiotherapy could be successfully deferred or obviated in a number of patients. Survival was high in among patients with monothalamic tumors. The worse prognosis associated with bithalamic tumors correlates with the higher rate of diffuse histology in this subgroup, precluding total or near-total resection. [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]

Purpose: Fusiform dilatations of the internal carotid artery (FDCA) represent a vascular complication following surgery for suprasellar tumors in children. Incidence rate and long-term prognosis of FDCA in terms of survival rates, vascular complications, and quality of survival are unknown for patients with childhood-onset craniopharyngioma. Methods: Magnetic resonance imaging (MRI) results of 583 patients with childhood-onset craniopharyngioma, recruited from 2001 to 2015 in the German Childhood Craniopharyngioma Registry, were reviewed for FDCA. Risk factors for FDCA and long-term outcome after FDCA were analyzed. Results: Fourteen of 583 patients (2.4 %) developed FDCA based on reference assessment of MRI. FDCA occurred ipsilateral to the surgical approach and was not related to degree of resection, hypothalamic involvement, or irradiation. The median time interval between first detection of FDCA and initial surgery was 0.79 years (range 0.01-5.56 years). During a median follow-up of 6.47 years (range 1.2-21.9 years) after first detection of FDCA, no bleeding or cerebrovascular events were observed in any patient. Irradiation was not related to FDCA. Survival rates and functional capacity were similar in patients with and without FDCA. Clinically the FDCA was unapparent in all cases and not treated. Conclusion: FDCA is a rare complication related to surgical treatment of childhood-onset craniopharyngioma without major impact on prognosis and clinical course of the disease. Clinical trial number: KRANIOPHARYNGEOM 2000-NCT00258453; KRANIOPHARYNGEOM 2007-NCT01272622. [ABSTRACT FROM AUTHOR]

Pediatric high-grade gliomas are considered to be different when compared to adult high-grade gliomas in their pathogenesis and biological behavior. Recently, common genetic alterations, including mutations in the H3F3A / ATRX / DAXX pathway, have been described in approximately 30% of the pediatric cases. However, only few cases of infant high-grade gliomas have been analyzed so far. We investigated the molecular features of 35 infants with diffuse high-grade astrocytomas, including 8 anaplastic astrocytomas [ World Health Organization ( WHO) grade III] and 27 glioblastomas ( WHO grade IV) by immunohistochemistry, multiplex ligation probe-dependent amplification ( MLPA), pyrosequencing of glioma-associated genes and molecular inversion probe ( MIP) assay. MIP and MLPA analyses showed that chromosomal alterations are significantly less frequent in infants compared with high-grade gliomas in older children and adults. We only identified H3F3A K27M in 2 of 34 cases (5.9%), with both tumors located in the posterior fossa. PDGFRA amplifications were absent, and CDKN2A loss could be observed only in two cases. Conversely, 1 q gain (22.7%) and 6 q loss (18.2%) were identified in a subgroup of tumors. Loss of SNORD located on chromosome 14 q32 was observed in 27.3% of the infant tumors, a focal copy number change not previously described in gliomas. Our findings indicate that infant high-grade gliomas appear to represent a distinct genetic entity suggesting a different pathogenesis and biological behavior. [ABSTRACT FROM AUTHOR]

Introduction: Pilomyxoid astrocytoma (PMA) is a rare WHO grade II tumor occurring most often in young children. PMA is associated with worse outcome as compared to the pathologically related pilocytic astrocytoma (PA). The radiological differentiation of PMAs from PAs is challenging. Furthermore, it is not completely clarified whether PMA is associated with a higher rate of cerebrospinal fluid (CSF) dissemination in the youngest pediatric population as compared to PA. The aim of our study was firstly to compare imaging features of these tumors and, secondly, to evaluate the occurrence of CSF dissemination. Methods: The study population included 15 children with PMA and 32 children with PA. The initial MRI and CT scans from the time of the diagnosis were retrospectively analyzed according to standardized criteria and the findings compared between the two tumor types. Furthermore, we also compared the occurrence of imaging evidences of CSF dissemination. Results: PMAs showed less frequently cystic components ( p = 0.03) and never had large tumor cysts. Gadolinium enhancement of PMAs was more frequently homogeneous ( p = 0.006). PMAs appeared to show more often intratumoral hemorrhages ( p = 0.047). Within the subgroup of children <6 years of age, the PMA histology tended to have a larger effect on the occurrence of CSF dissemination than the age ( p = 0.05 vs. 0.12). Conclusion: Some imaging features like enhancement pattern or presence of cysts or hemorrhage may help differentiating these low-grade gliomas. Our results confirm previous scarce data suggesting a higher rate of CSF dissemination in PMAs, even in the youngest patient population. [ABSTRACT FROM AUTHOR]