974 resultados para Brain Tumor


Relevância:

60.00% 60.00%

Publicador:

Resumo:

BACKGROUND: Cilengitide is a selective integrin inhibitor that is well tolerated and has demonstrated biologic activity in patients with recurrent malignant glioma. The primary objectives of this randomized phase 2 trial were to determine the safety and efficacy of cilengitide when combined with radiation and temozolomide for patients with newly diagnosed glioblastoma multiforme and to select a dose for comparative clinical testing. METHODS: In total, 112 patients were accrued. Eighteen patients received standard radiation and temozolomide with cilengitide in a safety run-in phase followed by a randomized phase 2 trial with 94 patients assigned to either a 500 mg dose group or 2000 mg dose group. The trial was designed to estimate overall survival benefit compared with a New Approaches to Brain Tumor Therapy (NABTT) Consortium internal historic control and data from the published European Organization for Research and Treatment of Cancer (EORTC) trial EORTC 26981. RESULTS: Cilengitide at all doses studied was well tolerated with radiation and temozolomide. The median survival was 19.7 months for all patients, 17.4 months for the patients in the 500 mg dose group, 20.8 months for patients in the 2000 mg dose group, 30 months for patients who had methylated O6-methylguanine-DNA methyltransferase (MGMT) status, and 17.4 months for patients who had unmethylated MGMT status. For patients aged ≤70 years, the median survival and survival at 24 months was superior to what was observed in the EORTC trial (20.7 months vs 14.6 months and 41% vs 27%, respectively; P = .008). CONCLUSIONS: Cilengitide was well tolerated when combined with standard chemoradiation and may improve survival for patients newly diagnosed with glioblastoma multiforme regardless of MGMT methylation status. The authors concluded that, from an efficacy and safety standpoint, future trials of this agent in this population should use the 2000 mg dose. Cancer 2012. © 2012 American Cancer Society.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Glioblastoma multiforme (GBM) tumors are the most common malignant primary brain tumors in adults. Although many GBM tumors are believed to be caused by self-renewing, glioblastoma-derived stem-like cells (GSCs), the mechanisms that regulate self-renewal and other oncogenic properties of GSCs are only now being unraveled. Here we showed that GSCs derived from GBM patient specimens express varying levels of the transcriptional repressor repressor element 1 silencing transcription factor (REST), suggesting heterogeneity across different GSC lines. Loss- and gain-of-function experiments indicated that REST maintains self-renewal of GSCs. High REST-expressing GSCs (HR-GSCs) produced tumors histopathologically distinct from those generated by low REST-expressing GSCs (LR-GSCs) in orthotopic mouse brain tumor models. Knockdown of REST in HR-GSCs resulted in increased survival in GSC-transplanted mice and produced tumors with higher apoptotic and lower invasive properties. Conversely, forced expression of exogenous REST in LR-GSCs produced decreased survival in mice and produced tumors with lower apoptotic and higher invasive properties, similar to HR-GSCs. Thus, based on our results, we propose that a novel function of REST is to maintain self-renewal and other oncogenic properties of GSCs and that REST can play a major role in mediating tumorigenicity in GBM. STEM CELLS 2012;30:405-414.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Le glioblastome multiforme (GBM) est la tumeur cérébrale la plus commune et létale chez l’adulte. Malgré les avancés fulgurantes dans la dernière décennie au niveau des thérapies contre le cancer, le pronostique reste inchangé. Le manque de spécificité des traitements est la cause première de la récurrence de cette tumeur. Une meilleure compréhension au niveau des mécanismes moléculaires et biologiques de cette tumeur est impérative. La découverte des cellules souches cancéreuses (CD133+) au niveau du GBM offre une nouvelle opportunité thérapeutique contre cette tumeur. Effectivement, les cellules CD133+ seraient responsables de l’établissement, le maintien et la progression du GBM. De plus, elles sont également la cause de la résistance du GBM faces aux traitements de radiothérapies. Ces cellules représentent une cible de choix dans le but d’éradiquer le GBM. L’oncogène BMI1 a été associé à plusieurs types de tumeurs et est également essentielle au maintien de différentes populations de cellules souches normales et cancéreuses. Une forte expression de BMI1 est observée au niveau du GBM et plus précisément, un enrichissement préférentiel de cette protéine est noté au niveau des cellules CD133+. L’objectif principal de cette thèse est d’évaluer le rôle potentiel de BMI1 dans le maintien et la radiorésistance des cellules souches cancéreuses (CSC), CD133+ du GBM. La fonction principale de BMI1 est la régulation négative du locus INK4A/ARF. Ce locus est impliqué dans l’activation de deux voies majeurs anti-tumorales : P53 et RB. Or, la perte de BMI1 induit in vitro une diminution des capacités prolifératives, une augmentation de la différentiation et de l’apoptose, ainsi qu’une augmentation de la radiosensibilité des CSC du GBM indépendamment de la présence du locus INK4A/ARF. Effectivement, deux tumeurs sur trois possèdent une délétion de ce locus, ce qui suggère que BMI1 possède d’autre(s) cible(s) transcriptionnelle(s). Parmi ces nouvelles cibles ont retrouve la protéine P21, un régulateur négatif du cycle cellulaire. De plus, la perte de BMI1 inhibe l’établissement d’une tumeur cérébrale lors d’études de xénogreffe chez la souris NOD/SCID. Également, une nouvelle fonction de BMI1 indépendante de son activité transcriptionnel a été démontrée. Effectivement, suite à l’induction d’un bris double brin (BDB) de l’ADN, BMI1 est rapidement recruté au niveau de la lésion et influence le recrutement des protéines de reconnaissance du dommage à l’ADN. La perte de BMI1 mène à un défaut au niveau de la reconnaissance et la réparation de l’ADN, alors que sa surexpression induit plutôt une augmentation de ces mécanismes et procure une radiorésistance. Ces résultats décrivent pour la première fois l’importance de BMI1 au niveau du maintien, de l’auto-renouvellement et la radiorésistance des CSC du GBM. Ainsi, ces travaux démontrent que la protéine BMI1 représente une cible thérapeutique de choix dans le but d’éradiquer le GBM, une tumeur cérébrale létale.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

La cirugía radioguiada es una rama de la medicina nuclear con la cual se marca el tejido tumoral con un radiotrazador (MIBI) y mediante el uso de una gamasonda o gamacámara poder diferenciarlo del tejido cerebral sano in vivo en la sala de cirugía. Esta técnica se ha aplicado con éxito en tumores del SNC (Gliomas de alto grado, metástasis, meningiomas). Los tumores del SNC representan el 1% de todos los tumores pero son la tercera causa de mortalidad por cáncer en el mundo. Hay un mejor pronóstico de los pacientes con mayor extensión de la resección. Objetivos: Evaluar la factibilidad de la técnica y optimizar los procesos en el INC con la finalidad de desarrollar un protocolo de línea de investigación en esta materia. Materiales y métodos: se realiza un reporte de casos de pacientes con diagnóstico de tumor cerebral supratentorial. Se realizó SPECT cerebral con MIBI para confirmar captación del radiotrazador. En los pacientes que marcaron positivo se programó cirugía radioguiada con gamacámara portátil Sentinel Resultados: En 5 pacientes con tumores supratentoriales se realizó SPECT cerebral con MIBI: 3 de ellos fueron positivos los cuales fueron programados para cirugía radioguiada y los 2 restantes con cirugía convencional. Dos de los casos positivos correspondieron a Tumor de alto grado y un caso de tumor abscedado. En quienes se practicó la cirugía radioguiada se consiguió resección tumoral completa tumoral por imagen de gamacámara intraquirúrgica

Relevância:

60.00% 60.00%

Publicador:

Resumo:

El Glioblastoma multiforme (GBM), es el tumor cerebral más frecuente, con pronóstico grave y baja sensibilidad al tratamiento inicial. El propósito de este estudio fue evaluar si la Difusión en RM (IDRM), es un biomarcador temprano de respuesta tumoral, útil para tomar decisiones tempranas de tratamiento y para obtener información pronostica. Metodología La búsqueda se realizo en las bases de datos EMBASE, CENTRAL, MEDLINE; las bibliografías también fueron revisadas. Los artículos seleccionados fueron estudios observacionales (casos y controles, cohortes, corte transversal), no se encontró ningún ensayo clínico; todos los participante tenían diagnostico histopatológico de GBM, sometidos a resección quirúrgica y/o radio-quimioterapia y seguimiento de respuesta al tratamiento con IDRM por al menos 6 meses. Los datos extraídos de forma independiente fueron tipo de estudio, participantes, intervenciones, seguimiento, desenlaces (sobrevida, progresión/estabilización de la enfermedad, muerte) Resultados Quince estudios cumplieron los criterios de inclusión. Entre las técnicas empleadas de IDRM para evaluar respuesta radiológica al tratamiento, fueron histogramas del coeficiente aparente de difusion ADC (compararon valores inferiores a la media y el percentil 10 de ADC, con los valores superiores); encontrando en términos generales que un ADC bajo es un fuerte predictor de sobrevida y/o progresión del tumor. (Esto fue significativo en 5 estudios); mapas funcionales de difusion (FDM) (midieron el porcentaje de cambio de ADC basal vs pos tratamiento) que mostro ser un fuerte predictor de sobrevida en pacientes con progresión tumoral. DISCUSION Desafortunadamente la calidad de los estudios fue intermedia-baja lo que hace que la aplicabilidad de los estudios sea limitada.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Neurocognitive impairment is being increasingly recognized as an important issue in patients with cancer who develop cognitive difficulties either as part of direct or indirect involvement of the nervous system or as a consequence of either chemotherapy-related or radiotherapy-related complications. Brain radiotherapy in particular can lead to significant cognitive defects. Neurocognitive decline adversely affects quality of life, meaningful employment, and even simple daily activities. Neuroprotection may be a viable and realistic goal in preventing neurocognitive sequelae in these patients, especially in the setting of cranial irradiation. Lithium is an agent that has been in use for psychiatric disorders for decades, but recently there has been emerging evidence that it can have a neuroprotective effect.

This review discusses neurocognitive impairment in patients with cancer and the potential for investigating the use of lithium as a neuroprotectant in such patients.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

PURPOSE: Thousands of children are living with advanced cancer; yet patient-reported outcomes (PROs) have rarely been used to describe their experiences. We aimed to describe symptom distress in 104 children age 2 years or older with advanced cancer enrolled onto the Pediatric Quality of Life and Evaluation of Symptoms Technology (PediQUEST) Study (multisite clinical trial evaluating an electronic PRO system).

METHODS: Symptom data were collected using age- and respondent-adapted versions of the PediQUEST Memorial Symptom Assessment Scale (PQ-MSAS) at most once per week. Clinical and treatment data were obtained from medical records. Individual symptom scores were dichotomized into high/low distress. Determinants of PQ-MSAS scores were explored using linear mixed-effects models.

RESULTS: During 9 months of follow-up, PQ-MSAS was administered 920 times: 459 times in teens (99% self-report), 249 times in children ages 7 to 12 years (96% child/parent report), and 212 times in those ages 2 to 6 years (parent reports). Common symptoms included pain (48%), fatigue (46%), drowsiness (39%), and irritability (37%); most scores indicated high distress. Among the 73 PQ-MSAS surveys administered in the last 12 weeks of life, pain was highly prevalent (62%; 58% with high distress). Being female, having a brain tumor, experiencing recent disease progression, and receiving moderate- or high-intensity cancer-directed therapy in the prior 10 days were associated with worse PQ-MSAS scores. In the final 12 weeks of life, receiving mild cancer-directed therapy was associated with improved psychological PQ-MSAS scores.

CONCLUSION: Children with advanced cancer experience high symptom distress. Strategies to promote intensive symptom management are indicated, especially with disease progression or administration of intensive treatments.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Despite recent advances, patients with malignant brain tumors still have a poor prognosis. Glioblastoma (WHO grade 4 astrocytoma), the most malignant brain tumor, represents 50% of all astrocytomas, with a median survival rate of <1 year. It is, therefore, extremely important to search for new diagnostic and therapeutic approaches for patients with glioblastoma. This study describes the application of superparamagnetic nano-particles of iron oxide, as well as monoclonal antibodies, of immunophenotypic significance, conjoined to quantum dots for the ultrastructural assessment of glioblastoma cells. For this proposal, an immunophenotypic study by flow cytometry was carried out, followed by transmission electron microscopy analysis. The process of tumor cell labeling using nanoparticles can successfully contribute to the identification of tumorigenic cells and consequently for better understanding of glioblastoma genesis and recurrence. In addition, this method may help further studies in tumor imaging, diagnosis, and prognostic markers detection.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

O glioma cordoide é um tumor cerebral raro, recentemente descrito, localizado na região do terceiro ventrículo e com características histológicas, imuno-histoquímicas e ultraestruturais peculiares. Este estudo ilustra um caso de glioma cordoide do terceiro ventrículo em uma paciente de 59 anos de idade.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

A pilomyxoid astrocytoma is a recently described tumor that occurs predominantly in the hypothalamic-chiasmatic region and is rarely found elsewhere. It has similar features as pilocytic astrocytomas, but has distinct histological characteristics and a poorer prognosis. A pilomyxoid astrocytoma is an aggressive tumor, and increased awareness is necessary with a suspect case. We present the first case of a pilomyxoid astrocytoma of the brainstem described after the newest World Health Organization classification of central nervous system tumors. © F.O. Pereira et al., 2013. Licensee PAGEPress, Italy.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

O Meduloblastoma é a neoplasia encefálica mais comum na infância, correspondendo a taxas de 16 a 25% de todos os tumores encefálicos em menores de 19 anos e 30-40% de todos os tumores da fossa posterior. Para investigar o papel do polimorfismo de base única (SNP) TP53 Arg72Pro sobre o risco de desenvolvimento, prognóstico e resposta a terapêutica adjuvante em Meduloblastoma, foi realizado um estudo caso-controle com 122 pacientes e 122 controles saudáveis do Brasil. Em comparação com Arg/Arg, que é o genótipo mais comum na população em estudo, tanto o genótipo Arg/Pro e Pro/Pro não influenciaram o risco de desenvolvimento de Meduloblastoma (OR = 1,36 e P = 0,339 para o genótipo Arg/Pro; OR = 1,50 e P = 0,389 para o genótipo Pro/Pro). Com relação ao prognóstico, a sobrevida livre de doença não foi significativamente diferente entre os genótipos SNP TP53 Arg72Pro (P> 0,05), porém o genótipo menos freqüente, Pro/Pro, foi associado a uma menor sobrevida global dos pacientes com Meduloblastoma (P = 0,021 ). Estes dados sugerem que embora não haja nenhuma associação entre o SNP TP53 Arg72Pro e o risco de desenvolvimento de Meduloblastoma, o genótipo Pro/Pro está associado a uma menor sobrevida global dos pacientes submetidos a terapia adjuvante. No entanto, devido à composição interétnica da população brasileira, futuros estudos envolvendo populações maiores e de outras partes do mundo serão essenciais para uma conclusão definitiva da função do SNP TP53 Arg72Pro.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

À luz da Linguística de Corpus e da Fraseologia, discutiremos aspectos teóricometodológicos que nos possibilitaram o levantamento de colocações e de colocações especializadas na área médica, a partir do corpus formado pelas transcrições dos episódios da série House M.D. Apresentamos também as colocações especializadas formadas com base nos nódulos ‘blood’, ‘brain’, ‘tumor’ e ‘heart’, a fim de exemplificar como as colocações serão organizadas em um glossário bilíngue de colocações especializadas na área médica, que se encontra em fase de compilação.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Pós-graduação em Biociências e Biotecnologia Aplicadas à Farmácia - FCFAR

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Meningiomas are the most common benign neoplasm of the brain whereas ectopic presentation, although reported, is rare. Among these ectopic tumors, there are a group of purely intraosseous meningiomas, which usually are diagnosed differentially from common primary osseous tumor such as fibrous dysplasia and osteoid osteoma. We report a 62-year-old female with a history of headaches and 6 months of progressive right parietal bulging, with no neurological signs. Parietal craniotomy was performed with immediate titanium cranioplasty of the parietal convexity. Histopathology exams revealed an ectopic intradiploic meningioma without invasion of cortical layers, with positive staining for progesterone receptors and epithelial membrane antigen. Ectopic intraosseous meningiomas remain a rare neoplasm with only a few cases reported. The main theories to justify the unusual topography appear to be embryological remains of neuroectodermal tissue or cellular dedifferentiation. Surgical treatment seems the best curative option.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Patients with primary malignant brain tumor endure several motor and cognitive dysfunctions, demanding the presence of a caregiver even more because the time necessary for their assistance increases considerably. Usually this task is performed by a family relative, whose activities include taking care of the patient’s personal hygiene, escorting them to medical appointments, managing their money and performing their housework. All of this overwhelms the caregiver both physical and psychologically. This bibliographic research intends to analyze the role in which a caregiver plays in the quality of life of those kinds of patients, the complications of such task, the caregivers’ needs and the daily life of those terminal patients. It was used CAPES, PubMed and Google Academic databases for researching articles related to family caregivers who assisted adult patients with primary malignant brain tumor. The study concluded that being a caregiver of patients in such conditions harms one’s quality of life, with consequences such as stress, insomnia, financial problems and lack of social support. Theirs needs include: having someone to talk to about the matter, attending programs for reducing stress and increasing their knowledge about the disease. In advanced phases of the condition, the patient shows great mobility problems, aphasia and regular seizures, which end up overwhelming the caregiver. The level of quality of life found was above other types of cancer’s caregivers. Therefore, they represent a group with special needs, which should be especially handled by health professionals.