Search results for "Astrocytoma"
showing 10 items of 50 documents
Melatonin Secretion and Increased Daytime Sleepiness in Childhood Craniopharyngioma Patients
2002
Craniopharyngioma is a rare dysontogenetic benign tumor. Patients frequently suffer from endocrine deficiencies, sleep disturbances, and obesity due to pituitary and hypothalamic lesions. A self-assessment daytime sleepiness questionnaire (German version of the Epworth Sleepiness Scale) was used to evaluate 79 patients with childhood craniopharyngioma. Because hypothalamic lesions may explain daytime sleepiness in craniopharyngioma patients, salivary melatonin and cortisol concentrations were examined in obese and nonobese craniopharyngioma patients (n = 79), patients with hypothalamic pilocytic astrocytoma (n = 19), and control subjects (n = 30). Using a general linear model procedure anal…
Long-term follow-up of children with magnetic resonance imaging and ultrasound after treatment of brain tumors
1987
This paper compares the results of MRI and US follow-up examinations of 46 children who had undergone surgery for brain tumors. The cases included 42 posterior fossa tumors, 3 supratentorial tumors and 1 upper cervical spinal cord tumor. US examination proved to be less specific and sensitive than MRI. However, when a "bone window" is available, US is, because of the ease of its application, better suited for frequent routine examinations. Long-term follow-up should, therefore, consist of frequent regular US examinations combined with yearly MRI examinations.
Characterization of BOLD-fMRI signal during a verbal fluency paradigm in patients with intracerebral tumors affecting the frontal lobe.
2002
Previous studies have indicated that the BOLD-fMRI signal can be modified by tumor processes in close vicinity to functional brain areas. This effect has been investigated primarily for the perirolandic area but there is only a limited number of studies concerning frontal cortical regions. Therefore, the aim of the current study was to characterize BOLD-fMRI signal and activation patterns in patients with frontal brain tumors while performing a verbal fluency task. Six patients (ages 31-56 years) suffering from frontal (5 left sided and 1 right sided) intracerebral tumors were examined with fMRI while performing a verbal fluency task in a blocked paradigm design. Eight healthy volunteers se…
The histology of brain tumors for 67 331 children and 671 085 adults diagnosed in 60 countries during 2000-2014: a global, population-based study (CO…
2021
Abstract Background Global variations in survival for brain tumors are very wide when all histological types are considered together. Appraisal of international differences should be informed by the distribution of histology, but little is known beyond Europe and North America. Methods The source for the analysis was the CONCORD database, a program of global surveillance of cancer survival trends, which includes the tumor records of individual patients from more than 300 population-based cancer registries. We considered all patients aged 0-99 years who were diagnosed with a primary brain tumor during 2000-2014, whether malignant or nonmalignant. We presented the histology distribution of th…
Brain Mapping-Aided SupraTotal Resection (SpTR) of Brain Tumors: The Role of Brain Connectivity
2021
Brain gliomas require a deep knowledge of their effects on brain connectivity. Understanding the complex relationship between tumor and functional brain is the preliminary and fundamental step for the subsequent surgery. The extent of resection (EOR) is an independent variable of surgical effectiveness and it correlates with the overall survival. Until now, great efforts have been made to achieve gross total resection (GTR) as the standard of care of brain tumor patients. However, high and low-grade gliomas have an infiltrative behavior and peritumoral white matter is often infiltrated by tumoral cells. According to these evidences, many efforts have been made to push the boundary of the re…
Accurate classification of childhood brain tumours by in vivo H-1 MRS - A multi-centre study
2013
Aims: To evaluate the accuracy of single-voxel Magnetic Resonance Spectroscopy (1H-MRS) as a non-invasive diagnostic aid for pediatric brain tumours in a multi-national study. Our hypotheses are (1) that automated classification based on 1H-MRS provides an accurate non-invasive diagnosis in multi-centre datasets and (2) using a protocol which increases the metabolite information improves the diagnostic accuracy. Methods: 78 patients under 16 years old with histologically proven brain tumours from 10 international centres were investigated. Discrimination of 29 medulloblastomas, 11 ependymomas and 38 pilocytic astrocytomas was evaluated. Single-voxel MRS was undertaken prior to diagnosis (1.…
Blood flow and metabolic microenvironment of brain tumors
1994
Summarizing thesein vivo data in the context of brain tumor therapy, the following aspects are of particular importance: Low and heterogeneous tumor blood flow may — in addition to the limiting effects of the blood-brain barrier — result in compromised delivery of drugs from blood to the tissue. Low tumor pO2 reduces sensitivity to standard radiation and ‘O2-dependent’ anticancer drugs. Treatment efficacy may be further altered by changes of tumor pH. Particularly acidosis can decrease radiation sensitivity and modulate the cytotoxicity of anticancer drugs. In the following presentations, these aspects will be discussed regardingin vivo data obtained with positron emission tomography.
MGMT activity, promoter methylation and immunohistochemistry of pretreatment and recurrent malignant gliomas: a comparative study on astrocytoma and …
2010
The DNA repair protein O(6)-methylguanine-DNA methyltransferase (MGMT) is a key player in tumor cell resistance. Promoter methylation, MGMT activity and immunohistochemistry are used for determining the MGMT status. However, it is unclear whether MGMT promoter methylation correlates with MGMT activity and whether MGMT promoter methylation of the pretreatment tumor predicts the MGMT status of recurrences. To address these questions, we determined MGMT activity promoter methylation and immunoreactivity in pretreatment and recurrent glioblastomas (GB, WHO Grade IV), and in astrocytomas (WHO Grade III). We show that GB that were promoter methylated display a range of 0-62 fmol/mg MGMT and tumor…
Risk factors for central nervous system tumors in children: New findings from a case-control study
2017
BACKGROUND: Central nervous system tumors (CNS) are the most frequent solid tumor in children. Causes of CNS tumors are mainly unknown and only 5% of the cases can be explained by genetic predisposition. We studied the effects of environmental exposure on the incidence of CNS tumors in children by subtype, according to exposure to industrial and/or urban environment, exposure to crops and according to socio-economic status of the child. METHODS: We carried out a population-based case-control study of CNS tumors in Spain, covering 714 incident cases collected from the Spanish Registry of Childhood Tumors (period 1996-2011) and 4284 controls, individually matched by year of birth, sex, and au…
Children <1 year show an inferior outcome when treated according to the traditional LGG treatment strategy: A report from the german multicenter t…
2013
Background Children diagnosed with LGG at an age <1 year are reported to have an impaired prognosis in comparison to older patients. Analysis of this subgroup could reveal the necessity to develop risk-adapted treatment approaches. Procedure Children <1 year at diagnosis (n = 66, median age 7.3 months, 33 female, none NFI) from the HIT-LGG 1996 cohort were analyzed for risk factors for EFS, PFS and OS. Several children suffered from diencephalic syndrome (DS, n = 22) and primary dissemination (DLGG, n = 9), 50 had a supratentorial midline (SML) location. Extent of resection was complete/subtotal in 12, partial in 15, biopsy in 27. Tumors were pilocytic astrocytoma WHO grade I (n = 33), othe…