Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 167
Filtrar
1.
AJNR Am J Neuroradiol ; 42(4): 759-765, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33574103

RESUMEN

BACKGROUND AND PURPOSE: B-Raf proto-oncogene, serine/threonine kinase (BRAF) status has important implications for prognosis and therapy of pediatric low-grade gliomas. Currently, BRAF status classification relies on biopsy. Our aim was to train and validate a radiomics approach to predict BRAF fusion and BRAF V600E mutation. MATERIALS AND METHODS: In this bi-institutional retrospective study, FLAIR MR imaging datasets of 115 pediatric patients with low-grade gliomas from 2 children's hospitals acquired between January 2009 and January 2016 were included and analyzed. Radiomics features were extracted from tumor segmentations, and the predictive model was tested using independent training and testing datasets, with all available tumor types. The model was selected on the basis of a grid search on the number of trees, opting for the best split for a random forest. We used the area under the receiver operating characteristic curve to evaluate model performance. RESULTS: The training cohort consisted of 94 pediatric patients with low-grade gliomas (mean age, 9.4 years; 45 boys), and the external validation cohort comprised 21 pediatric patients with low-grade gliomas (mean age, 8.37 years; 12 boys). A 4-fold cross-validation scheme predicted BRAF status with an area under the curve of 0.75 (SD, 0.12) (95% confidence interval, 0.62-0.89) on the internal validation cohort. By means of the optimal hyperparameters determined by 4-fold cross-validation, the area under the curve for the external validation was 0.85. Age and tumor location were significant predictors of BRAF status (P values = .04 and <.001, respectively). Sex was not a significant predictor (P value = .96). CONCLUSIONS: Radiomics-based prediction of BRAF status in pediatric low-grade gliomas appears feasible in this bi-institutional exploratory study.


Asunto(s)
Neoplasias Encefálicas , Glioma , Proteínas Proto-Oncogénicas B-raf/genética , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Niño , Femenino , Glioma/diagnóstico por imagen , Glioma/genética , Humanos , Imagen por Resonancia Magnética , Masculino , Mutación , Proto-Oncogenes Mas , Curva ROC , Estudios Retrospectivos
2.
Neurochirurgie ; 67(1): 61-68, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31229532

RESUMEN

Medulloblastoma is the most common malignant brain tumors in children. Current management combines surgery, radiotherapy, and chemotherapy. Current treatment of medulloblastoma is based on a clinical risk-stratification system that takes into account age, extent of resection and metastatic status. High-risk medulloblastoma patients are defined by the presence of metastatic disease and/or an incomplete resection with a residual amount of tumour>1.5 cm2. This review describes the evolution in the management of high-risk medulloblastoma patients during recent 4 decades and recent changes in the definition of high-risk patients as a result of major advances in the understanding of the molecular heterogeneity of medulloblastomas.


Asunto(s)
Neoplasias Cerebelosas/cirugía , Manejo de la Enfermedad , Progresión de la Enfermedad , Meduloblastoma/cirugía , Neoplasias Cerebelosas/diagnóstico por imagen , Niño , Preescolar , Ensayos Clínicos como Asunto/métodos , Femenino , Humanos , Masculino , Meduloblastoma/diagnóstico por imagen , Factores de Riesgo
3.
Clin Oncol (R Coll Radiol) ; 31(8): 539-548, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31182288

RESUMEN

Although neoplasms of the brain and central nervous system (CNS) are relatively uncommon, comprising only 1-2% of the overall cancer burden, they represent a substantial source of morbidity and mortality worldwide. The age-adjusted annual incidence of CNS tumours is reportedly low; however, there is substantial global variability in its incidence, with nearly a five-fold difference between regions with the highest rates in developed countries in the West and those with the lowest rates in developing countries in South-East Asia, including India, possibly attributable to key differences in environmental factors, genetic susceptibilities and cultural practices, as well as resource constraints in low-middle income countries precluding precise ascertainment and accurate diagnosis. The burden of CNS tumours is further compounded by the fact that they require highly specialised and skilled multidisciplinary care, including access to modern neuroimaging, neurosurgery, neuropathology and molecular biology, radiotherapy, chemotherapy and rehabilitation services, which may not be widely available in an integrated manner in large parts of the world with a large variation in clinical pathways, non-uniformity of care and resultant heterogeneity in clinical outcomes. CNS tumours encompass a heterogeneous spectrum of histopathological entities with differences in presentation, distinct molecular/genetic alterations, diverse biological behaviour and varying clinical outcomes. Survival is highly dependent on histology, grade and molecular biology, but varies widely across continents, even for the same tumour type and grade. In general, survival is higher in children with primary brain tumours than in adults, largely due to the differences in histological distribution across age groups. However, there is widespread variability, with 5-year survival for paediatric brain tumours being <40% in some low-middle income countries compared with 70-80% in the developed world. This review compares the descriptive epidemiology and clinical outcomes of primary brain tumours between the East and the West that pose unique challenges but also provide new opportunities in contemporary neuro-oncological practice.


Asunto(s)
Neoplasias Encefálicas/epidemiología , Neoplasias del Sistema Nervioso Central/epidemiología , Neoplasias Encefálicas/patología , Neoplasias del Sistema Nervioso Central/patología , Femenino , Humanos , India , Resultado del Tratamiento
5.
J Neurooncol ; 133(3): 581-587, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28508928

RESUMEN

Embryonal tumors are a heterogeneous group of central nervous system (CNS) tumors whose subgroups have varying incidence and outcome. Despite these differences, they are often grouped as a single entity for study purposes. To date, there are no Canadian multi-institutional studies examining the incidence and outcome of all embryonal subtypes. The current study is an observational study reviewing embryonal tumors in all patients less than 36 months of age diagnosed with a CNS tumor in Canada from 1990 to 2005. Embryonal tumors accounted for 26.9% of all CNS tumors. Medulloblastomas were the highest proportion of the embryonal tumors at 61.5%. Atypical teratoid/rhabdoid tumors (AT/RT) had the second highest proportion of embryonal tumors at 18%. The proportion of primitive neuroectodermal tumors (PNET) was 16%, with 2.6 and 1.9% for congenital medulloepithelioma and ependymoblastoma tumors, respectively. AT/RT and PNET were more common in younger age groups. Medulloblastoma became more prevalent with increasing age, with its highest prevalence in the 25 to 36 month age group. Survival rates for our Canadian population at 18 and 24 months were 0.74 and 0.68 for medulloblastoma, 0.64 and 0.60 for PNET, and 0.36 and 0.29 for AT/RT, respectively. Overall, our data are comparable with published international rates for embryonal tumors. These incidence and outcome figures can guide future research into these rare tumors.


Asunto(s)
Neoplasias del Sistema Nervioso Central/epidemiología , Neoplasias de Células Germinales y Embrionarias/epidemiología , Canadá/epidemiología , Neoplasias del Sistema Nervioso Central/terapia , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Neoplasias de Células Germinales y Embrionarias/terapia , Análisis de Supervivencia
6.
Eur J Cancer ; 80: 63-72, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28551430

RESUMEN

AIMS: We examined the efficacy of exercise training for improving physical functioning and cardiopulmonary fitness in survivors of paediatric brain tumours (BTs) treated with cranial irradiation. METHODS: We conducted a controlled clinical trial with crossover of exercise training versus no training in the community in either a group or combined group/home setting. A volunteer sample of 28 children treated with cranial irradiation for brain tumours completed training (mean age = 11.53 years; mean time since diagnosis = 5.25 years). end-points were physical functioning assessed by four subtests from the Bruininks-Oseretsky Test of motor performance (BOT-2) and pro-rated work rate from a cycle ergometer. Linear mixed modelling was used to evaluate time, training, training setting, and carryover effects. RESULTS: Adherence to training was 84%. Performance on the BOT-2 was below average for all assessments. However, training resulted in improvement in bilateral coordination (F (1, 30) = 6.59, p = 0.02), irrespective of training setting and improved performance was maintained even approximately 12°weeks after training had ended (F (1, 24) = 9.60, p = 0.005). Training resulted in increased pro-rated work rate for participants in the group training setting only (F (1, 25) = 4.57, p = 0.04) and these participants maintained their improved work rate approximately 12°weeks after training had ended (F (1, 20) = 8.38, p = 0.01). CONCLUSION: Exercise training improves physical functioning and fitness in paediatric BT survivors. Exercise interventions that ameliorate adverse physical effects and promote health in long-term survivors are highly recommended in this vulnerable population. (ClinicalTrials.gov, NCT01944761).


Asunto(s)
Neoplasias Encefálicas , Irradiación Craneana/efectos adversos , Terapia por Ejercicio , Destreza Motora/fisiología , Acondicionamiento Físico Humano , Aptitud Física/fisiología , Sobrevivientes , Neoplasias Encefálicas/fisiopatología , Neoplasias Encefálicas/radioterapia , Capacidad Cardiovascular/fisiología , Niño , Preescolar , Femenino , Humanos , Modelos Lineales , Masculino , Calidad de Vida
7.
J Neurooncol ; 133(1): 119-128, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28405869

RESUMEN

High-dose chemotherapy (HDC) strategies were developed in brain tumor protocols for young children to prevent neuropsychological (NP) impairments associated with radiotherapy. However, comprehensive NP evaluations of these children treated with such strategies remain limited. We examined the long-term neurocognitive outcomes of young children (<6 years) with medulloblastoma, treated similarly, with a HDC strategy "according to" the chemotherapy regimen of the protocol CCG 99703. This retrospective study included young children less than 6 years of age at diagnosis of medulloblastoma treated from 1998 to 2011 at 7 North American institutions. Twenty-four patients who had at least one NP assessment post-treatment are the focus of the current study. Of 24 patients in this review, 15 (63%) were male and the mean age at diagnosis was 29.4 months (SD = 13.5). Posterior fossa syndrome (PFs) was reported in five patients (21%). Nine (37.5%) received radiotherapy (5 focal, 4 craniospinal). On average, children were assessed 3.5 years (SD = 1.8) post-diagnosis, and full-scale intellectual quotient (FSIQ) scores ranged from 56 to 119 ([Formula: see text]= 92; SD = 16.8). The majority of children (74%) had low-average to average NP functioning. Very young children treated with radiotherapy, who needed hearing support or with PFs had worse neurocognitive outcomes. Clinically significant deficits (<10th percentile) in at least one area of NP functioning were found in 25% of the children. NP data obtained from this sample of survivors of medulloblastoma in early childhood, all treated with sequential HDC and 1/3 with radiotherapy, describe NP functioning within average normal limits overall. However, almost 25% of children had significant deficits in specific domains.


Asunto(s)
Neoplasias Encefálicas/psicología , Neoplasias Encefálicas/terapia , Meduloblastoma/psicología , Meduloblastoma/terapia , Adolescente , Quimioradioterapia , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Pruebas Neuropsicológicas , Estudios Retrospectivos
8.
AJNR Am J Neuroradiol ; 35(7): 1263-9, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24831600

RESUMEN

BACKGROUND AND PURPOSE: Recently identified molecular subgroups of medulloblastoma have shown potential for improved risk stratification. We hypothesized that distinct MR imaging features can predict these subgroups. MATERIALS AND METHODS: All patients with a diagnosis of medulloblastoma at one institution, with both pretherapy MR imaging and surgical tissue, served as the discovery cohort (n = 47). MR imaging features were assessed by 3 blinded neuroradiologists. NanoString-based assay of tumor tissues was conducted to classify the tumors into the 4 established molecular subgroups (wingless, sonic hedgehog, group 3, and group 4). A second pediatric medulloblastoma cohort (n = 52) from an independent institution was used for validation of the MR imaging features predictive of the molecular subtypes. RESULTS: Logistic regression analysis within the discovery cohort revealed tumor location (P < .001) and enhancement pattern (P = .001) to be significant predictors of medulloblastoma subgroups. Stereospecific computational analyses confirmed that group 3 and 4 tumors predominated within the midline fourth ventricle (100%, P = .007), wingless tumors were localized to the cerebellar peduncle/cerebellopontine angle cistern with a positive predictive value of 100% (95% CI, 30%-100%), and sonic hedgehog tumors arose in the cerebellar hemispheres with a positive predictive value of 100% (95% CI, 59%-100%). Midline group 4 tumors presented with minimal/no enhancement with a positive predictive value of 91% (95% CI, 59%-98%). When we used the MR imaging feature-based regression model, 66% of medulloblastomas were correctly predicted in the discovery cohort, and 65%, in the validation cohort. CONCLUSIONS: Tumor location and enhancement pattern were predictive of molecular subgroups of pediatric medulloblastoma and may potentially serve as a surrogate for genomic testing.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias Cerebelosas/metabolismo , Neoplasias Cerebelosas/patología , Meduloblastoma/metabolismo , Meduloblastoma/patología , Proteínas de Neoplasias/metabolismo , Proteínas Wnt/metabolismo , Adolescente , Adulto , Neoplasias Cerebelosas/clasificación , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Meduloblastoma/clasificación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Método Simple Ciego , Adulto Joven
9.
Psychooncology ; 22(11): 2436-44, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23737306

RESUMEN

OBJECTIVE: This prospective and longitudinal study was designed to further our understanding of parental hope when a child is being treated for a malignancy resistant to treatment over three time points during the first year after diagnosis using a qualitative approach to inquiry. METHODS: We prospectively recruited parents of pediatric cancer patients with a poor prognosis who were treated in the Hematology/Oncology Program at a large children's hospital for this longitudinal grounded theory study. Parents were interviewed at three time points: within 3 months of the initial diagnosis, at 6 months, and at 9 months. Data collection and analysis took place concurrently using line-by-line coding. Constant comparison was used to examine relationships within and across codes and categories. RESULTS: Two overarching categories defining hope as a positive inner source were found across time, but their frequency varied depending on how well the child was doing and disease progression: future-oriented hope and present-oriented hope. Under future-oriented hope, we identified the following: hope for a cure and treatment success, hope for the child's future, hope for a miracle, and hope for more quality time with child. Under present-oriented hope, we identified hope for day-to-day/moment-to-moment, hope for no pain and suffering, and hope for no complications. CONCLUSIONS: For parents of children with a diagnosis of cancer with a poor prognosis, hope is an internal resource that can be present and future focused. These views fluctuated over time in response to changes in the child's well-being and disease progression.


Asunto(s)
Actitud Frente a la Salud , Neoplasias/psicología , Padres/psicología , Adolescente , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Humanos , Entrevistas como Asunto , Masculino , Neoplasias/terapia , Dolor , Relaciones Profesional-Familia , Pronóstico , Estudios Prospectivos , Investigación Cualitativa , Índice de Severidad de la Enfermedad
10.
Pediatr Radiol ; 42(5): 552-61, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22246411

RESUMEN

BACKGROUND: The quality of MRI and CT depends largely on immobility of the patient during the procedure, which is often difficult to achieve without sedation in children below the age of 6 years. OBJECTIVE: To assess the efficacy and safety of intravenous chlorpromazine sedation for repeated imaging in young children treated for cancer. MATERIALS AND METHODS: From July 2003 to January 2007, information on children younger than 6 years of age having MRI or CT was prospectively collected. Forty-five minutes before the scan, a 10-min infusion of chlorpromazine 0.5 mg/kg was administered and managed by non-anesthetic staff. Patient monitoring included continuous measurement of pulse, respiration, oxygen saturation and arterial blood pressure. Procedure-related parameters and adverse events were documented. Sedation was considered successful when the procedure was completed and at least 95% of images were usable. RESULTS: One-hundred-one procedures (82 MRI, 19 CT) were evaluated in 62 children, 3-74 months old. Adequate sedation was achieved in 96% of cases, with mean induction time, 22 min; mean duration of sleep, 72 min, and mean duration of procedure, 33 min. Mean time spent in the radiology unit was 104 min. Ninety-six percent of imaging procedures were successfully completed. No cardiac, respiratory, neurological or allergic complication occurred. CONCLUSION: Intravenous chlorpromazine is safe and effective for procedural sedation in young children with cancer undergoing MRI and CT.


Asunto(s)
Anestésicos Intravenosos/administración & dosificación , Clorpromazina/administración & dosificación , Sedación Profunda/métodos , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X , Niño , Preescolar , Femenino , Humanos , Lactante , Modelos Logísticos , Masculino , Monitoreo Fisiológico , Estudios Prospectivos
11.
Eur J Cancer ; 48(3): 353-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22023887

RESUMEN

BACKGROUND: Atypical teratoid rhabdoid tumours (ATRT) are aggressive brain tumours mostly occurring in early childhood. Largest published series arise from registries and institutional experiences (1-4). The aim of this report is to provide population-based data to further characterise this rare entity and to delineate prognostic factors. PATIENTS AND METHODS: A national retrospective study of children ⩽18years diagnosed with a central nervous system (CNS) ATRT between 1995 and 2007 was undertaken. All cases underwent central pathology review. RESULTS: There were 50 patients (31 males; median age at diagnosis of 16.7months). Twelve patients were >36months. Infratentorial location accounted for 52% of all cases. Nineteen patients (38%) had metastatic disease. Fifteen (30%) underwent gross total resection (GTR). Ten patients (20%) underwent palliation. Among the 40 remaining patients, 22 received conventional chemotherapy and 18 received high dose chemotherapy regimens (HDC); nine received intrathecal chemotherapy and 15 received adjuvant radiation. Thirty of the 40 treated patients relapsed/progressed at a median time of 5.5months (0-32). The median survival time of the entire cohort was 13.5months (1-117.5months). Age, tumour location and metastatic status were not prognostic. Patients with GTR had a better survival (2years overall survival (OS): 60%±12.6 versus 21.7%±8.5, p=0.03). HDC conferred better outcome (2years OS 47.9%±12.1 versus 27.3%±9.5, p=0.036). Upfront radiation did not provide survival benefit. Six of the 12 survivors (50%) did not receive radiation. CONCLUSION: The outcome of CNS ATRT remains poor. However, the use of HDC provides encouraging results. GTR is a significant prognostic factor. The role of adjuvant radiation remains unclear.


Asunto(s)
Neoplasias del Sistema Nervioso Central , Tumor Rabdoide , Canadá/epidemiología , Neoplasias del Sistema Nervioso Central/mortalidad , Neoplasias del Sistema Nervioso Central/patología , Neoplasias del Sistema Nervioso Central/terapia , Niño , Preescolar , Estudios de Cohortes , Supervivencia sin Enfermedad , Femenino , Humanos , Lactante , Estimación de Kaplan-Meier , Masculino , Pronóstico , Estudios Retrospectivos , Tumor Rabdoide/mortalidad , Tumor Rabdoide/patología , Tumor Rabdoide/terapia , Análisis de Supervivencia
12.
Curr Oncol ; 18(1): e19-24, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21331268

RESUMEN

OBJECTIVE: To describe the use of temozolomide (tmz) in Canadian children treated for brain tumours and to evaluate survival and predictors of survival for children treated with this agent. METHODS: A survey was conducted within the Canadian Paediatric Brain Tumour Consortium (cpbtc), a group of tertiary care centres in pediatric neuro-oncology (n = 16) in Canada that are involved in the treatment of children with central nervous system tumours. RESULTS: In 10 of the 16 participating pediatric oncology centres of the cpbtc, 137 children with brain tumours were treated with tmz between January 2000 and March 2006. Although 33% of the children were enrolled into a clinical trial, 67% were treated outside open studies. Most patients (72%) received tmz treatment on recurrence of their brain tumour (first or subsequent). The most commonly administered regimen was single-agent tmz 150-200 mg/m(2) administered on 5 consecutive days every 28 days. The median duration of tmz treatment was 141 days (range: 4-1102 days). Response data were provided for 127 of the 137 patients, of whom 6 showed a complete response. Sixteen patients experienced a minor or partial response, 53 had stable disease, and 52 had progressive disease. Of 32 patients alive at last follow-up, 19 had a diagnosis of low-grade glioma. CONCLUSIONS: Temozolomide is used in a variety of pediatric brain tumours, often at the time of recurrence. The lack of insight into clear indications for this agent in pediatric brain tumours-used either alone or in combination therapy-may be a result of suboptimal design of phase i and ii studies and a lack of phase iii trials in the pediatric brain tumour population.

14.
Curr Oncol ; 17(3): 2-3, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20567618
15.
Curr Oncol ; 16(6): 21-8, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20016743

RESUMEN

PURPOSE: Concerns about radiotherapy-related neurocognitive sequelae in young children have led to deferral or avoidance of radiation in contemporary treatment for this fragile group of patients. We compared survival and neurocognitive outcome in two groups of infants with medulloblastoma who received adjuvant conventional craniospinal irradiation (CSI) or reduced or no radiotherapy during an era of change in the philosophy of infant medulloblastoma treatment. PATIENTS AND METHODS: From 1985 to 2007, 29 patients 3 years of age or younger were diagnosed and treated with curative intent in our institution. Children treated before 1994 received adjuvant radiation with chemotherapy; subsequently, radiation was prescribed essentially for disease progression or relapse. RESULTS: Median age at diagnosis was 24 months (range: 1-36 months); 15 patients (52%) presented with metastatic disease at diagnosis. As part of initial treatment, 8 children received adjuvant radiotherapy with chemotherapy, and 21 children received postoperative chemotherapy only. Five children treated with chemotherapy alone are in prolonged remission. The 5-year event-free and overall survivals were 35.9% +/- 9.8% and 50.2% +/- 9.6% respectively. Extent of resection, metastatic status, and desmoplastic histology were not found to be significant prognostic factors. On serial neurocognitive evaluations, patients treated with chemotherapy with or without reduced radiotherapy demonstrated improvement of intellectual function over time. Patients treated with conventional csi exhibited significantly lower intelligence quotient scores and academic performance, with the exception of receptive vocabulary. CONCLUSIONS: Avoidance of conventional CSI in treatment of very young children with medulloblastoma appears to be associated with a preserved neurocognitive profile. Neurocognitive evaluation should be integrated into the primary objectives of future infant protocols.

16.
Br J Cancer ; 101(4): 722-33, 2009 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-19603027

RESUMEN

BACKGROUND: Juvenile pilocytic astrocytomas (JPA), a subgroup of low-grade astrocytomas (LGA), are common, heterogeneous and poorly understood subset of brain tumours in children. Chromosomal 7q34 duplication leading to fusion genes formed between KIAA1549 and BRAF and subsequent constitutive activation of BRAF was recently identified in a proportion of LGA, and may be involved in their pathogenesis. Our aim was to investigate additional chromosomal unbalances in LGA and whether incidence of 7q34 duplication is associated with tumour type or location. METHODS AND RESULTS: Using Illumina-Human-Hap300-Duo and 610-Quad high-resolution-SNP-based arrays and quantitative PCR on genes of interest, we investigated 84 paediatric LGA. We demonstrate that 7q34 duplication is specific to sporadic JPA (35 of 53 - 66%) and does not occur in other LGA subtypes (0 of 27) or NF1-associated-JPA (0 of 4). We also establish that it is site specific as it occurs in the majority of cerebellar JPA (24 of 30 - 80%) followed by brainstem, hypothalamic/optic pathway JPA (10 of 16 - 62.5%) and is rare in hemispheric JPA (1 of 7 - 14%). The MAP-kinase pathway, assessed through ERK phosphorylation, was active in all tumours regardless of 7q34 duplication. Gain of function studies performed on hTERT-immortalised astrocytes show that overexpression of wild-type BRAF does not increase cell proliferation or baseline MAPK signalling even if it sensitises cells to EGFR stimulation. CONCLUSIONS AND INTERPRETATION: Our results suggest that variants of JPA might arise from a unique site-restricted progenitor cell where 7q34 duplication, a hallmark of this tumour-type in association to MAPK-kinase pathway activation, potentially plays a site-specific role in their pathogenesis. Importantly, gain of function abnormalities in components of MAP-Kinase signalling are potentially present in all JPA making this tumour amenable to therapeutic targeting of this pathway.


Asunto(s)
Astrocitoma/genética , Biomarcadores de Tumor/genética , Neoplasias Encefálicas/genética , Cromosomas Humanos Par 7/genética , Adolescente , Astrocitoma/metabolismo , Astrocitoma/patología , Western Blotting , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Proteínas Portadoras/genética , Niño , Preescolar , Femenino , Técnica del Anticuerpo Fluorescente , Dosificación de Gen , Duplicación de Gen , Humanos , Inmunohistoquímica , Masculino , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Polimorfismo de Nucleótido Simple , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas B-raf/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/fisiología
17.
J Neurooncol ; 95(2): 271-279, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19521664

RESUMEN

Medulloblastoma patients treated at the Institute Curie between 1980 and 2000 were reviewed. Only patients whose primary treatment included craniospinal radiation were considered. Surviving patients were identified and evaluated by means of self-report questionnaires using the Health Utility Index (HUI). Psychosocial functioning, employment, and other health-related indicators were recorded. Seventy-three patients were treated during the study period. At a median follow-up from diagnosis of 14.4 years, 49 patients were alive and 45 surviving patients could be contacted. Late sequelae were frequent, particularly neurological deficits (71%) and endocrine complications (52%). Impairments of psychosocial functioning, including employment, driving capacity, independent living, and marital status, were identified in most patients. Most long-term medulloblastoma survivors suffer persistent deficits in several domains, with a significant impact on their psychosocial functioning. These findings reinforce the importance of early intervention programs for all survivors in order to reduce the psychosocial impacts of their disease.


Asunto(s)
Neoplasias Cerebelosas/radioterapia , Irradiación Craneana , Meduloblastoma/radioterapia , Calidad de Vida , Neoplasias de la Médula Espinal/radioterapia , Adolescente , Neoplasias Cerebelosas/mortalidad , Neoplasias Cerebelosas/psicología , Niño , Preescolar , Femenino , Estudios de Seguimiento , Estado de Salud , Humanos , Lactante , Masculino , Meduloblastoma/mortalidad , Meduloblastoma/psicología , Pronóstico , Neoplasias de la Médula Espinal/mortalidad , Neoplasias de la Médula Espinal/psicología , Encuestas y Cuestionarios , Tasa de Supervivencia , Sobrevivientes , Resultado del Tratamiento
18.
Br J Cancer ; 99(7): 1129-35, 2008 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-18797459

RESUMEN

We have recently described the enzymatic subunit of telomerase (hTERT) as an important prognostic marker for paediatric ependymoma. Because of the lack of good, representative pre-clinical models for ependymoma, we took advantage of our large cohort of ependymoma patients, some with multiple recurrences, to investigate telomere biology in these tumours. Our cohort consisted of 133 ependymomas from 83 paediatric patients and included 31 patients with recurrences. Clinical outcome was measured as overall survival, progression-free survival and response to therapy. In all 133 tumours, hTERT expression correlated with proliferative markers, including MIB-1 index (P<0.0001) and mitotic index (P=0.005), as well as overall tumour grade (P=0.001), but not with other markers of anaplasia. There was no correlation between telomere length and hTERT expression or survival. Surprisingly, prior radiation or chemotherapy neither induced sustained DNA damage nor affected telomere maintenance in recurrent tumours. There was an inverse correlation between hTERT expression and telomere dysfunction as measured by gamma H2AX expression (P=0.016). Combining gamma H2AX and hTERT expressions could segregate tumours into three different survival groups (log rank, P<0.0001) such that those patients whose tumours expressed hTERT and showed no evidence of DNA damage had the worst outcome. This study emphasises the importance of telomere biology as a prognostic tool and telomerase inhibition as a therapeutic target for paediatric ependymoma. Furthermore, we have demonstrated that analysing tumours as they progress in vivo is a viable approach to studying tumour biology in humans.


Asunto(s)
Neoplasias del Sistema Nervioso Central/patología , Ependimoma/patología , Telómero , Neoplasias del Sistema Nervioso Central/genética , Neoplasias del Sistema Nervioso Central/terapia , Niño , Estudios de Cohortes , Ependimoma/genética , Ependimoma/terapia , Humanos , Inmunohistoquímica , Pronóstico , Recurrencia
19.
Pediatr Blood Cancer ; 49(6): 803-7, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17096408

RESUMEN

BACKGROUND: To evaluate the efficacy of BCNU, cisplatin, and vincristine (BCV regimen) in a prospective nonrandomized study among newly diagnosed children with high-grade glioma. PROCEDURE: Following surgery, patients received a combination of BCNU + cisplatin + VP16 (BCV), over 3 consecutive days. Patients with residual tumor continued this regimen unless no further improvement was observed on MRI, for a maximum of six courses. Patients who underwent complete surgical resection received six courses of adjuvant BCV. RESULTS: Seventy-three patients were enrolled. Out of 66 eligible patients with central pathology review, the diagnosis of high-grade glioma was confirmed in 53 cases. The response rate was 20%. With a median follow-up of 128 months, 5- and 10-year event free survival rates are 16 +/- 9 and 13.3 +/- 9.4%. In univariate analysis, two prognostic factors were statistically significant: extent of resection and tumor location, while macroscopic total resection was the only significant prognostic factor in the multivariate analysis. The response to BCV did not translate into improved event free survival. Interstitial pneumonitis occurred in seven patients, leading to six deaths. CONCLUSION: This BCV regimen could not be recommended in the treatment of high-grade gliomas in children, according to its lack of efficacy and its unacceptable pulmonary toxicity.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Glioma/terapia , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carmustina/efectos adversos , Carmustina/uso terapéutico , Quimioterapia Adyuvante/efectos adversos , Niño , Preescolar , Cisplatino/efectos adversos , Cisplatino/uso terapéutico , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Francia , Glioma/complicaciones , Glioma/diagnóstico , Glioma/mortalidad , Humanos , Enfermedades Pulmonares Intersticiales/inducido químicamente , Enfermedades Pulmonares Intersticiales/mortalidad , Masculino , Oncología Médica , Pediatría , Proyectos Piloto , Estudios Prospectivos , Sociedades Médicas , Tasa de Supervivencia , Vincristina/administración & dosificación , Vincristina/uso terapéutico
20.
J Neurooncol ; 82(3): 289-95, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17120159

RESUMEN

OBJECTIVES: To determine the incidence and characteristics of pediatric patients with central nervous system (CNS) germ cell tumors (GCT) in Canada. METHOD: A national retrospective review of hospital charts was done on all patients with CNS GCT diagnosed between 1990 and 2004. Patients had to be under age 18 years at the time of diagnosis of a CNS germ cell tumor and be a resident of Canada. Information extracted included age and year of diagnosis, pathological diagnosis, location of tumor, evidence of disseminated disease at time of diagnosis and biological markers. RESULTS: One hundred and twenty-one cases were identified (83 germinoma; 38 non-germinoma germ cell tumor). The mean annual incidence of CNS GCT was 1.06 per million children (0.7 per million for germinoma; 0.3 per million for NGGCT). Though yearly incidences varied, there was no clear trend to increased incidence. Male predominance was noted (2.4:1 for germinoma; 11:1 for NGGCT). The primary locations were the pineal and suprasellar regions. At the time of diagnosis, disseminated disease was not uncommon (22% germinoma; 32% NGGCT). Beta human gonadotrophin was elevated in the serum, cerebrospinal fluid (CSF) or both in 7% of patients with germinoma and 36% of patients with NGGCT. Elevation of alpha-fetoprotein in serum, CSF or both was seen in 34% of patients with NGGCT. CONCLUSION: The incidence of CNS germ cell tumors in Canadian children is similar to that observed in other Western countries.


Asunto(s)
Neoplasias del Sistema Nervioso Central/epidemiología , Neoplasias de Células Germinales y Embrionarias/epidemiología , Adolescente , Canadá/epidemiología , Niño , Preescolar , Femenino , Humanos , Incidencia , Masculino , Estudios Retrospectivos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA