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Medulloblastoma (MB) comprises a group of heterogeneous paediatric embryonal neoplasms of the hindbrain with strong links to early development of the hindbrain1-4. Mutations that activate Sonic hedgehog signalling lead to Sonic hedgehog MB in the upper rhombic lip (RL) granule cell lineage5-8. By contrast, mutations that activate WNT signalling lead to WNT MB in the lower RL9,10. However, little is known about the more commonly occurring group 4 (G4) MB, which is thought to arise in the unipolar brush cell lineage3,4. Here we demonstrate that somatic mutations that cause G4 MB converge on the core binding factor alpha (CBFA) complex and mutually exclusive alterations that affect CBFA2T2, CBFA2T3, PRDM6, UTX and OTX2. CBFA2T2 is expressed early in the progenitor cells of the cerebellar RL subventricular zone in Homo sapiens, and G4 MB transcriptionally resembles these progenitors but are stalled in developmental time. Knockdown of OTX2 in model systems relieves this differentiation blockade, which allows MB cells to spontaneously proceed along normal developmental differentiation trajectories. The specific nature of the split human RL, which is destined to generate most of the neurons in the human brain, and its high level of susceptible EOMES+KI67+ unipolar brush cell progenitor cells probably predisposes our species to the development of G4 MB.

Sonic hedgehog medulloblastoma encompasses a clinically and molecularly diverse group of cancers of the developing central nervous system. Here, we use unbiased sequencing of the transcriptome across a large cohort of 250 tumors to reveal differences among molecular subtypes of the disease, and demonstrate the previously unappreciated importance of non-coding RNA transcripts. We identify alterations within the cAMP dependent pathway (GNAS, PRKAR1A) which converge on GLI2 activity and show that 18% of tumors have a genetic event that directly targets the abundance and/or stability of MYCN. Furthermore, we discover an extensive network of fusions in focally amplified regions encompassing GLI2, and several loss-of-function fusions in tumor suppressor genes PTCH1, SUFU and NCOR1. Molecular convergence on a subset of genes by nucleotide variants, copy number aberrations, and gene fusions highlight the key roles of specific pathways in the pathogenesis of Sonic hedgehog medulloblastoma and open up opportunities for therapeutic intervention.

Over the past decade, wingless-activated (WNT) medulloblastoma has been identified as a candidate for therapy de-escalation based on excellent survival; however, a paucity of relapses has precluded additional analyses of markers of relapse. To address this gap in knowledge, an international cohort of 93 molecularly confirmed WNT MB was assembled, where 5-year progression-free survival is 0.84 (95%, 0.763-0.925) with 15 relapsed individuals identified. Maintenance chemotherapy is identified as a strong predictor of relapse, with individuals receiving high doses of cyclophosphamide or ifosphamide having only one very late molecularly confirmed relapse (p = 0.032). The anatomical location of recurrence is metastatic in 12 of 15 relapses, with 8 of 12 metastatic relapses in the lateral ventricles. Maintenance chemotherapy, specifically cumulative cyclophosphamide doses, is a significant predictor of relapse across WNT MB. Future efforts to de-escalate therapy need to carefully consider not only the radiation dose but also the chemotherapy regimen and the propensity for metastatic relapses.

While molecular subgrouping has revolutionized medulloblastoma classification, the extent of heterogeneity within subgroups is unknown. Similarity network fusion (SNF) applied to genome-wide DNA methylation and gene expression data across 763 primary samples identifies very homogeneous clusters of patients, supporting the presence of medulloblastoma subtypes. After integration of somatic copy-number alterations, and clinical features specific to each cluster, we identify 12 different subtypes of medulloblastoma. Integrative analysis using SNF further delineates group 3 from group 4 medulloblastoma, which is not as readily apparent through analyses of individual data types. Two clear subtypes of infants with Sonic Hedgehog medulloblastoma with disparate outcomes and biology are identified. Medulloblastoma subtypes identified through integrative clustering have important implications for stratification of future clinical trials.

BackgroundPatients with incomplete surgical resection of medulloblastoma are controversially regarded as having a marker of high-risk disease, which leads to patients undergoing aggressive surgical resections, so-called second-look surgeries, and intensified chemoradiotherapy. All previous studies assessing the clinical importance of extent of resection have not accounted for molecular subgroup. We analysed the prognostic value of extent of resection in a subgroup-specific manner.MethodsWe retrospectively identified patients who had a histological diagnosis of medulloblastoma and complete data about extent of resection and survival from centres participating in the Medulloblastoma Advanced Genomics International Consortium. We collected from resections done between April, 1997, and February, 2013, at 35 international institutions. We established medulloblastoma subgroup affiliation by gene expression profiling on frozen or formalin-fixed paraffin-embedded tissues. We classified extent of resection on the basis of postoperative imaging as gross total resection (no residual tumour), near-total resection (30 Gy vs no craniospinal irradiation). The primary analysis outcome was the effect of extent of resection by molecular subgroup and the effects of other clinical variables on overall and progression-free survival.FindingsWe included 787 patients with medulloblastoma (86 with WNT tumours, 242 with SHH tumours, 163 with group 3 tumours, and 296 with group 4 tumours) in our multivariable Cox models of progression-free and overall survival. We found that the prognostic benefit of increased extent of resection for patients with medulloblastoma is attenuated after molecular subgroup affiliation is taken into account. We identified a progression-free survival benefit for gross total resection over sub-total resection (hazard ratio [HR] 1·45, 95% CI 1·07-1·96, p=0·16) but no overall survival benefit (HR 1·23, 0·87-1·72, p=0·24). We saw no progression-free survival or overall survival benefit for gross total resection compared with near-total resection (HR 1·05, 0·71-1·53, p=0·8158 for progression-free survival and HR 1·14, 0·75-1·72, p=0·55 for overall survival). No significant survival benefit existed for greater extent of resection for patients with WNT, SHH, or group 3 tumours (HR 1·03, 0·67-1·58, p=0·89 for sub-total resection vs gross total resection). For patients with group 4 tumours, gross total resection conferred a benefit to progression-free survival compared with sub-total resection (HR 1·97, 1·22-3·17, p=0·0056), especially for those with metastatic disease (HR 2·22, 1·00-4·93, p=0·050). However, gross total resection had no effect on overall survival compared with sub-total resection in patients with group 4 tumours (HR 1·67, 0·93-2·99, p=0·084).InterpretationThe prognostic benefit of increased extent of resection for patients with medulloblastoma is attenuated after molecular subgroup affiliation is taken into account. Although maximum safe surgical resection should remain the standard of care, surgical removal of small residual portions of medulloblastoma is not recommended when the likelihood of neurological morbidity is high because there is no definitive benefit to gross total resection compared with near-total resection.FundingCanadian Cancer Society Research Institute, Terry Fox Research Institute, Canadian Institutes of Health Research, National Institutes of Health, Pediatric Brain Tumor Foundation, and the Garron Family Chair in Childhood Cancer Research.

This is a testimony of the impact caused by the Covid-19 pandemic in educational and family settings and affairs, from the perspective of the teacher and the student: lockdown, distance learning, the isolation effects on family and school health. Was it a general deterioration/cognitive impairment or a challenge to learn in some other way? [ABSTRACT FROM AUTHOR]

Abstract Background Neuroblastoma (NB) is the principal tumor of the sympathetic nervous system in children under one year of age. The incidence in developed countries is greater than that in developing countries. The aim of this article is to present the epidemiological and some clinical characteristics of Mexican children with NB. Methods A population-based, prolective study, with data obtained from the Childhood Cancer Registry of the Instituto Mexicano de Seguro Social. Statistical analysis: The simple frequencies of the variables of the study and the annual average incidence (per 1,000,000 children/years) by age and sex were obtained. The trend was evaluated by calculating the annual percentage of change. The curves of Kaplan-Meyer were employed for the survival rate and the log-rank test was used to compare the curves. Results Of a total of 2,758 children with cancer registered during the period from 1996–2005, 72 (2.6%) were identified as having Group IV, defined according to the International Classification of Childhood Cancer. The incidence for NB was 3.8 per 1,000,000 children/year; NB was highest in the group of children under one year of age, followed by the group of children between the ages 1–4 years (18.5 and 5.4 per 1,000,000 children/years, respectively). The male/female ratio was 1.1 and there was no trend toward an increase. The time of diagnosis was 26 days (median), but varied according to the stage at diagnosis. Stages III and IV were presented in 88% of the cases. There was no association between the stage, the age at time of diagnosis, or the histological pattern. The overall five-year survival rate was 64%; the patients with stage I, II, III, or IVs did not die; and the five-year survival rate of cases in Stage IV was 40%. Conclusion It is possible that the low incidence of neuroblastoma in Mexican children is due to the difficulty in diagnosing the cases with the best prognosis, some of which could have had spontaneous regression. There was no trend to an increase; the majority of the cases were diagnosed in the advanced stages; and the overall five-years survival rate was similar to that for developed countries.

César Rodríguez Chicharro was a poet-teacher man pertaining to the Young Hispanic-Mexican group of people arriving to Mexico as a consequence of the Spaniard Civil War. Afterwards, Rodríguez Chicharro devoted his life to Literature. Event though, he worked in several literary branches, Rodriguez Chicharro shaped up as a poet and essayist. Professionally, he dedicated his life to teaching and literary research, as well as a prominent bibliophile. Notwithstanding the quality and originality of his poetic work, it is not well known and has not been collected in one single volume. [ABSTRACT FROM AUTHOR]

Federico Patan (Gijon, 1937) is a writer/author pertaining to the Spanish Mexican group of writers from the mid xx Century. He has perfectly combined his literary outcome, with teaching and the academic research. Federico Patan works include poetry, essays, tales, novels, memories, translation and cultural journalism. He is generally highly recognized by his narrative works, though his poetry is as important and meaningful as Patan has widely exercised it since youth. It represents the literary outcome that better describes his literary and intellectual work. [ABSTRACT FROM AUTHOR]

Background: Survival of children with pineal region tumors has increased significantly in the last decade; these tumors have an insidious outcome associated with endocrine disorders with high morbidity and mortality, especially after gross resection. The objective was to report the survival, outcome, morbidity and mortality according to type of surgery, histology and treatment in children with pineal region tumors. Methods: This retrospective study included all patients of 17 years or less with diagnosis of pineal region tumor, who went over a period of 10 years to a children’s hospital. A histopathological review was made, and the extent of resection was determined. The survival was also estimated. Results: Forty-six patients were included, out of which 36 had complete medical records and adequate pathologic material. Gross resection was performed in 24 (66.6 %), and biopsy in 12 (33.3 %); 23 (88 %) patients died; hydroelectrolytic imbalance was the cause of 14 deaths (60 %) and the other nine (39.1 %) were secondary to tumor progression. Ten-years survivals among patients treated with gross resection and biopsy were 52 and 75 %, respectively (p = 0.7). Endocrine alterations were observed in 13 patients (36.1 %); in 10 of these (76.9 %) the total resection was performed. Conclusion: Pineal region tumors in children can be treated with diagnostic biopsy, followed by adjuvant treatment consisting of chemotherapy and radiotherapy. [ABSTRACT FROM AUTHOR]

Background: Cytogenetics has revealed that the development of brain tumors might be induced by molecular alterations. The association of chromosomal imbalances with survival will allow for the prognosis and treatment of these tumors to be assessed. The objective of this study was to determine chromosomal imbalances and overall and disease-free survival in pediatric patients with astrocytoma and the association between chromosomal imbalances and survival. Methods: Medical charts of patients diagnosed with astrocytoma according to records from 1995 to 2005 were reviewed. Paraffin blocks were retrieved in order to extract tumor material and a comparative genomic hybridization technique was used to search for chromosomal gains and losses. Results: Out of 35 patients, 31 had at least some alteration in chromosomes 1, 5, 9 or 18, the latter with gains or losses in 65.7 % of the patients. By histology, 7/9 pilocytic astrocytomas had alteration of chromosome 9, and in 5/6 anaplastic astrocytomas, of chromosome 18. Patients with alterations in these chromosomes had a worse survival. Conclusions: The results of this study suggest that there is an association between the anaplastic histology and chromosome 18 alterations, as well as between diffuse astrocytoma and alterations in chromosome 5, which could be relevant in the Latin American population. [ABSTRACT FROM AUTHOR]

Introduction: Cardiotoxicity is an adverse reaction associated with the use of anthracyclines., Objective: To estimate the factors associated with the development of anthracycline cardiotoxicity in pediatric patients surviving cancer., Method: Retro-prolective cohort of children diagnosed with cancer and treated with anthracyclines. Baseline echocardiographic determination of ejection fraction (LVEF0) was carried out before the start of treatment and again at 12 months (LVEF1). Demographic characteristics and treatment were obtained from the medical record. A multiple logistic regression (MLR) model was constructed; LVEF1 < 50 % was the dependent variable, which was adjusted for the main confounding variables., Results: Sixty-five patients were included, out of which 36.9 % were females and 56.8 % had a solid tumor. LVEF0 was 74.79 ± 7.3 % and LVEF1, 67.96 ± 6.7 % (p = 0.001); 60 % developed cardiotoxicity. In the MLR, only a cumulative dose > 430 mg was associated with cardiotoxicity (p = 0.001)., Conclusions: In Mexican children, an anthracycline cumulative dose > 430 mg should be avoided in order to prevent cardiotoxicity., (Copyright: © 2020 Permanyer.)

Background: Survival of children with pineal region tumors has increased significantly in the last decade; these tumors have an insidious outcome associated with endocrine disorders with high morbidity and mortality, especially after gross resection. The objective was to report the survival, outcome, morbidity and mortality according to type of surgery, histology and treatment in children with pineal region tumors., Methods: This retrospective study included all patients of 17 years or less with diagnosis of pineal region tumor, who went over a period of 10 years to a children's hospital. A histopathological review was made, and the extent of resection was determined. The survival was also estimated., Results: Forty-six patients were included, out of which 36 had complete medical records and adequate pathologic material. Gross resection was performed in 24 (66.6 %), and biopsy in 12 (33.3 %); 23 (88 %) patients died; hydroelectrolytic imbalance was the cause of 14 deaths (60 %) and the other nine (39.1 %) were secondary to tumor progression. Ten-years survivals among patients treated with gross resection and biopsy were 52 and 75 %, respectively (p = 0.7). Endocrine alterations were observed in 13 patients (36.1 %); in 10 of these (76.9 %) the total resection was performed., Conclusions: Pineal region tumors in children can be treated with diagnostic biopsy, followed by adjuvant treatment consisting of chemotherapy and radiotherapy.

Background: Cytogenetics has revealed that the development of brain tumors might be induced by molecular alterations. The association of chromosomal imbalances with survival will allow for the prognosis and treatment of these tumors to be assessed. The objective of this study was to determine chromosomal imbalances and overall and disease-free survival in pediatric patients with astrocytoma and the association between chromosomal imbalances and survival., Methods: Medical charts of patients diagnosed with astrocytoma according to records from 1995 to 2005 were reviewed. Paraffin blocks were retrieved in order to extract tumor material and a comparative genomic hybridization technique was used to search for chromosomal gains and losses., Results: Out of 35 patients, 31 had at least some alteration in chromosomes 1, 5, 9 or 18, the latter with gains or losses in 65.7 % of the patients. By histology, 7/9 pilocytic astrocytomas had alteration of chromosome 9, and in 5/6 anaplastic astrocytomas, of chromosome 18. Patients with alterations in these chromosomes had a worse survival., Conclusions: The results of this study suggest that there is an association between the anaplastic histology and chromosome 18 alterations, as well as between diffuse astrocytoma and alterations in chromosome 5, which could be relevant in the Latin American population.