Pediatric brain tumors in sub-Saharan Africa: a systematic review and meta-analysis.

OBJECTIVE: Brain tumors are a global problem, leading to higher cancer-related morbidity and mortality rates in children. Despite the progressive though slow advances in neuro-oncology care, research, and diagnostics in sub-Saharan Africa (SSA), the epidemiological landscape of pediatric brain tumors (PBTs) remains underestimated. This study aimed to systematically analyze the distribution of PBT types in SSA. METHODS: Ovid Medline, Global Index Medicus, African Journals Online, Google Scholar, and faculty of medicine libraries were searched for literature on PBTs in SSA published before October 29, 2022. A proportional meta-analysis was performed. RESULTS: Forty-nine studies, involving 2360 children, met the inclusion criteria for review; only 20 (40.82%) were included in the quantitative analysis. South Africa and Nigeria were the countries with the most abundant data. Glioma not otherwise specified (NOS) was the common PBT in the 4 SSA regions combined. However, medulloblastoma was more commonly reported in Southern SSA (p = 0.01) than in other regions. The prevalence and the overall pooled proportion of the 3 common PBTs was estimated at 46.27% and 0.41 (95% CI 0.32-0.50, 95% prediction interval [PI] 0.11-0.79), 25.34% and 0.18 (95% CI 0.14-0.21, 95% PI 0.06-0.40), and 12.67% and 0.12 (95% CI 0.09-0.15, 95% PI 0.04-0.29) for glioma NOS, medulloblastoma, and craniopharyngioma, respectively. Sample size moderated the estimated proportion of glioma NOS (p = 0.02). The highest proportion of craniopharyngiomas was in Western SSA, and medulloblastoma and glioma NOS in Central SSA. CONCLUSIONS: These findings provide insight into the trends of PBT types and the proportion of the top 3 most common tumors across SSA. Although statistical conclusions are difficult due to the inconsistency in the data, the study identifies critical areas for policy development and collaborations that can facilitate improved outcomes in PBTs in SSA. More accurate epidemiological studies of these tumors are needed to better understand the burden of the disease and the geographic variation in their distribution, and to raise awareness in their subsequent management.

Epidemiology and Anatomical Distribution of Primary Brain Tumors Among Children in Palestine: A 6-Year National Referral Institution Study.

OBJECTIVE: To investigate the incidence rate of primary brain tumors (PBTs) among Palestinian children over a 6-year interval. This study also aimed to identify the predominant histopathologic types identified in these children. METHODS: This retrospective epidemiologic study focused on PBTs in children (<15 years) in Palestine. The data were collected from the registry system at Al-Makassed Hospital in Jerusalem, a prominent referral institution in Palestine and the largest center for PBTs in the region, over a 6 years period from 2018 to 2023. RESULTS: The incidence rate of PBTs in children (<15 years) was 1.33 per 100,000 person-years, with a 5% mortality rate. Pilocytic astrocytoma was the most common type (24%), followed by medulloblastoma (15.2%) and glioblastoma (6.3%). About one half of the tumors in children were malignant. Headaches were the most common first sign or symptom. About 20% of brain tumors in children were situated within the ventricles, making it the most prevalent location of these tumors, followed by the cerebellum (15.19%) and frontal lobe (11.39%). CONCLUSIONS: This is the first national study in Palestine investigating PBTs in children. The crude incidence rate of primary brain tumors among Palestinian children was lower than the incidence rate in many countries around the world. It is recommended that more research be done on the epidemiology and distribution of PBTs in children in Palestine.

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

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

Meduloblastoma: correlação entre ressonância magnética convencional, difusão e espectroscopia de prótons / Medulloblastoma: correlation among findings of conventional magnetic resonance imaging, diffusion-weighted imaging and proton magnetic resonance spectroscopy", "_i": "en

OBJETIVO: Correlacionar os achados de ressonância magnética convencional, difusão e espectroscopia de prótons nos meduloblastomas, e compará-los aos dados da literatura. MATERIAIS E MÉTODOS: Análise retrospectivade exames de ressonância magnética pré-operatórios de nove pacientes na faixa pediátrica com diagnóstico histológico de meduloblastoma (oito desmoplásicos e um de células gigantes). Foram considerados dados demográficos e características do tumor como localização, característica morfológica, intensidade de sinal, realce, disseminação e achados na difusão e espectroscopia. RESULTADOS: Na maioria dos casos os tumores apresentaram epicentro no vermis cerebelar (77,8%), sendo predominantemente sólido (88,9%), com hipossinal nas seqüências ponderadas em T1 e iso/hipersinal nas seqüências ponderadas em T2 e FLAIR, realce heterogêneo (100%), sinais de disseminação/extensão tumoral (77,8%) e restrição à movimentação das moléculas de água (100%). A espectroscopia de prótons pela técnica STEAM (n = 6) demonstrou redução da relação Naa/Cr (83,3%) e aumento de Co/Cr (100%) e mI/Cr (66,7%), e pela técnica PRESS (n = 7) evidenciou pico de lactato (57,1%). CONCLUSÃO: O conjunto dos achados macroscópicosobtidos pela ressonância magnética, somado às características bioquímicas dos meduloblastomas, têm sido úteis na tentativa de diferenciação entre os principais tumores da fossa posterior.

OBJECTIVE: To correlate imaging findings of medulloblastomas at conventional magnetic resonance imaging, diffusion-weighted imaging and proton magnetic resonance spectroscopy, comparing them with data in the literature. MATERIALS AND METHODS: Preoperative magnetic resonance imaging studies of nine pediatric patients with histologically confirmed medulloblastomas (eight desmoplastic medulloblastoma, and one giant cell medulloblastoma) were retrospectively reviewed, considering demographics as well as tumorscharacteristics such as localization, morphology, signal intensity, contrast-enhancement, dissemination, anddiffusion-weighted imaging and spectroscopy findings. RESULTS: In most of cases the tumors were centeredin the cerebellar vermis (77.8%), predominantly solid (88.9%), hypointense on T1-weighted images andintermediate/hyperintense on T2-FLAIR-weighted images, with heterogeneous enhancement (100%), tumor dissemination/extension (77.8%) and limited water molecule mobility (100%). Proton spectroscopy acquiredwith STEAM technique (n = 6) demonstrated decreased Naa/Cr ratio (83.3%) and increased Co/Cr (100%)and mI/Cr (66.7%) ratios; and with PRESS technique (n = 7) demonstrated lactate peak (57.1%). CONCLUSION: Macroscopic magnetic resonance imaging findings in association with biochemical features of medulloblastomas have been useful in the differentiation among the most frequent posterior fossa tumors. Keywords: Medulloblastoma; Infratentorial neoplasms; Pediatric brain tumors; Magnetic resonance imaging;Diffusion-weighted magnetic resonance imaging; Magnetic resonance spectroscopy.

Células madre: implicaciones en el desarrollo de tumores cerebrales / Stem cells: implications in the development of brain tumors

Las células madre se caracterizan por su capacidad de renovarse, dar origen a nuevas células en tejidos específicos, y mantener esta capacidad a lo largo de toda la vida del anfitrión. Las células madre son pluripotenciales y mantienen una producción continua de neuronas, astrocitos y oligodendrocitos. Las células madre en los tumores cerebrales también proliferan, se renuevan y dan origen a otras células pobremente diferenciadas. La diferencia entre células madre no tumorales y tumorales reside en que estas últimas carecen de los mecanismos normales que regulan la proliferación y diferenciación, resultando en una producción incontrolada y en una diferenciación incompleta de células tumorales. Descubrir el papel que juegan las células madre tumorales en el cerebro nos ha proporcionado una nueva perspectiva con respecto a las vías de señal moleculares y a la oncogénesis en el sistema nervioso central, y puede ayudarnos a explicar el alto número de recurrencias en algunos tumores y la naturaleza difusa de los glioblastomas; idealmente, puede esperarse que esta perspectiva conduzca a mejores tratamientos. Este artículo revisa las características de las células madre no tumorales y tumorales, con énfasis en la importancia que las células madre tumorales cerebrales tienen en la patogénesis de neoplasias cerebrales comunes (AU)

Stem cells are characterized by their capacity for self-renewal, for giving rise to new cells in specific tissues, and for maintaining this capacity throughout the entire life of their host. Stem cells are pluripotent and maintain continuous production of neurons, astrocytes, and oligodendrocytes. Stem cells in brain tumors also proliferate, undergo self-renewal, and give rise to other poorly differentiated cells. Unlike non-tumor stem cells, tumor stem cells lack the normal mechanisms that regulate proliferation and differentiation, resulting in uncontrolled production and incomplete differentiation of tumor cells. Discovering the role of tumor stem cells in the brain has given us a new perspective about the molecular pathways involved in signaling and about oncogenesis in the central nervous system; it can also help us explain the high rate of recurrence of some tumors and the diffuse nature of glioblastomas. Ideally, this perspective can be expected to lead to better treatments. This article reviews the characteristics of non-tumor and tumor stem cells, emphasizing the importance of brain tumor stem cells in the pathogenesis of common brain tumors (AU)

Population-based study of medulloblastoma: outcomes in Alberta from 1975 to 1996

BACKGROUND:The purpose of this study was to determine incidence, survival rate, and prognostic factors as well as the frequency of Collins' Law Violators (CLVs) in an unselected population of medulloblastoma patients. Collins' Law dictates that 'cure' of a child with a tumor occurs after a period that includes the child's age at diagnosis plus 9 months.METHODS:Using the Alberta Cancer Registry a population-based review identified 49 patients with medulloblastoma (19 adults, 30 children) diagnosed from 1975-96. Pathology was reviewed in all cases. All patients had surgical resection, followed by radiotherapy in 47 patients and chemotherapy in 17.RESULTS:The overall 5-year survival was 50%. There was a trend for the extent of resection to be associated with a longer survival (Long rank test, p < 0.06) but this was not significant. Tumor recurrence occurred a median of 22.4 months (range, 6.4-192.3) after diagnosis and median survival after recurrence was 9.3 months (range, 0.4-64.9). The survival curve did not appear to plateau but was affected by tumor-related deaths in 3 (21.4%) of the 21 long-term survivors diagnosed in childhood. These three patients had recurrences a mean of 11.7 years after diagnosis and are designated as CLVs.CONCLUSIONS:The survival rate in an unselected population of patients with medulloblastoma is poor. Aggressive resection of the tumors prolongs survival. The Collins' Law Violators were relatively common and we suggest this concept be abandoned in medulloblastoma(AU)

Meduloblastomas: achados clínicos, epidemiológicos e anátomo-patológicos de 28 casos / Medulloblastomas: clinical, epidemiological and pathological findings of 28 cases

Relatamos os achados clínicos, epidemiológicos e anátomo-patológicos de 28 casos de meduloblastomas. Dos 28 pacientes analisados, 22 eram do sexo masculino e seis do sexo feminino. As idades variaram de 1 a 50 anos, com média de 15 anos. Os sinais e sintomas de maior frequência foram cefaléia (64 por cento) e vômitos (64 por cento). Em relação ao tratamento, a maioria dos pacientes foi submetida a ressecção cirúrgica total (n=10) ou a exérese parcial (n=7). Com a exceção de um paciente que apresentava meduloblastoma desmoplásico, os demais apresentavam a forma clássica do meduloblastoma. Foi evidenciada uma taxa de recidiva tumoral total de 21 por cento (n=6) em 4 anos de seguimento clínico. A quimioterapia adjuvante parece contribuir para melhor evolução clínica dos pacientes. Estes achados aproximam-se dos encontrados na literatura, contribuindo para a compreensão do comportamento biológico deste tumor.

Meduloblastoma / Meduloblastoma

Se revisan todos los casos de Meduloblastoma diagnosticados y comprobados con Biopsia, en el Instituto de Anatomia Patologica del Hospital Universitario de San Vicente de Paul, desde el 1 de Enero de 1975, al 1 de Enero de 1980. Se encuentran 11 casos, todos suceptibles de seguimiento. Hay predominancia en hombres, en relacion de 1.75 a 1. El promedio de edad es de 8.6 anos, y el 64 X 100 de los pacientes son menores de 10 anos. La incidencia parece ir en aumento, a juzgar por el numero de pacientes que se han tabulado luego de la fecha del corte, y con miras a un informe posterior. La cefalea, el vomito y la ataxia, fueron los sintomas predominantes para la consulta. Una gran mayoria (mas del 90 X 100) de los tumores, son del vermis, y el resto del hemisferio, (tumor de adulto). Todos los pacientes fueron operados, la mayoria con reseccion macroscopicamente completa del tumor y 9 recibieron un regimen completo de terapia ionizante post-operatoria. De estos ultimos, la supervivencia es de 55.55 X 100 y la supervivencia global, es de 45.45 X 100. El tiempo entre cirugia y radioterapia fue en promedio 24 dias. La causa de muerte, es, casi siempre, la recidiva en fosa posterior

Avances en neuropediatria / Advances in neuropediatry

Diagnósticos prenatales de patología neuropediátrica. Embarazo y epilepsia, medicación, efectos sobre el recien nacido. Convulsiones neonatales, febriles, afebriles, epilepsias: diagnóstico y tratamiento. Benzodiazepinas: farmacología. Absorción del diazepan por vía sublingual versus oral. Niveles sanguineos con dosis únicas y múltiples. Electromiografias, resonancia magnética y mapeo cerebral en neuropediatría. Actualización en tumores de fosa posterior: meduloblastoma

Avances en neuropediatria / Advances in neuropediatry

Diagnósticos prenatales de patología neuropediátrica. Embarazo y epilepsia, medicación, efectos sobre el recien nacido. Convulsiones neonatales, febriles, afebriles, epilepsias: diagnóstico y tratamiento. Benzodiazepinas: farmacología. Absorción del diazepan por vía sublingual versus oral. Niveles sanguineos con dosis únicas y múltiples. Electromiografias, resonancia magnética y mapeo cerebral en neuropediatría. Actualización en tumores de fosa posterior: meduloblastoma