Glioma
Glioma (Greek glia glue ) is a collective term for some brain tumors of the central nervous system. They arise most commonly from glial cells, which support and nutritive tissue of the nerve cells. They usually occur in the brain, but are also in the area of the spinal cord and cranial nerves possible.
History
The term glioma was first used by Rudolf Virchow in his eighteenth lecture on 7 February 1863 - the first description of the glial cells also goes back to him (1858 ). Virchow's classification has long been the basis for all subsequent divisions. Camillo Golgi struck before 1875 to limit the term to astrocytic glioma cells.
The major basis for current understanding of glioma delivered Harvey Cushing and Percival Bailey, who defined these tumors due to their histological similarities to glial cells in the 1920s. James Watson Kernohan introduced the concept of a biological graduation in 1949 and divided into four possible grade gliomas. Klaus Joachim Zülch merged the terminology of Cushing / Bailey with the Graduierungskonzept of Kernohan and thus laid the foundations of today's WHO classification of gliomas.
Classification
Cytogenetic origin
Gliomas are based on the glial cell type, they resemble histologically the most - but not necessarily of it descended - named. These include:
- Astrocytoma
- Oligodendroglioma
- Ependymoma
- Mischgliome
Malignancy
They can also according to their pathological significance ( WHO grade I - IV ) according to the WHO classification of tumors of the central nervous system are divided (eg, pilocytic astrocytoma WHO grade I, fibrillary astrocytoma WHO grade II, anaplastic astrocytoma WHO grade III, glioblastoma WHO grade IV).
Localization
We distinguish gliomas afterwards whether they are in the brain stem ( pontin ) over ( supratentorial ) or below ( infratentorial ) the tentorium are ( a transverse membrane between the occipital lobe of the cerebrum and cerebellum ).
WHO classification of tumors of the central nervous system (detail)
We distinguish between the following entities, among other things:
Neuroepithelial tumors
Diagnostics
The initial diagnosis corresponds to the type of brain tumor and is used to determine the location, extent and histology of the lesion. This is important for neurosurgical intervention planning.
At the beginning with a survey of the medical history (anamnesis). The most important diagnostic method is magnetic resonance imaging (MRI ) of the skull. An alternative, though less suitable for imaging methods, computer tomography is (CT). The confirmation of the diagnosis is usually by surgical removal of tissue (biopsy). In the area of the optic nerve but this is associated with a risk of emergence or increase of visual impairment.
Scientists at the University of California in 2008 developed a method to demonstrate the magnetic resonance imaging ( MRI) genes typical of the most common brain cancer variant can. One method that could also help in the early detection of gliomas, because the very slow growing tumor unobtrusive and thus remains undetected in young patients often over the years.
Causes and Risks
The exact reason for the development of gliomas is unknown. This is known as sporadic - in contrast to hereditary - tumors. Gliomas are therefore generally not inheritable ( exceptions are eg neurofibromatosis, Turcot syndrome or Li -Fraumeni syndrome).
In 2009, two conducted in the U.S. and Europe genome-wide association studies ( GWAS ) performed on five genes to the discovery of variants that could explain together up to a fifth of all gliomas ( publications in Nature Genetics ).
- INTERPHONE study by IARC (2000)
In the International Agency for Research on Cancer ( IARC) initiated an international case-control study ( INTERPHONE ) to determine a possible risk for the development of brain tumors through the use of mobile phones. There, among other things associated with the use of mobile phones health risks ( high-frequency electromagnetic fields) were examined. Two forms of primary tumors were considered, including gliomas, because they are the most common and aggressive type of brain tumor.
It has been reported, among other things, that the World Health Organization (WHO ) noted of developing intensive use of mobile phones as possibly carcinogenic panelist and among other things, an increased risk of glioma.
The information came from the IARC INTERPHONE study from 2004 pointed.
In a comparative study ( with data from the Interphone Study, 2010) U.S. researchers at the National Cancer Institute came to the conclusion to be able to find no increased risk of glioma due to cell phone radiation.
Therapy optimization
SIOP -LGG 2004 is a collaborative multicenter study for children and adolescents with a low grade glioma malignancy. It is promoted biometrics since 1 June 2004 by the German Childhood Cancer Foundation as part of the Reference Centre. SIOP stands for International Society of Paediatric Oncology and LGG for low grade glioma. The year marked the beginning of the study.
The aim of this international, multicenter therapy optimization study SIOP -LGG 2004 is to offer all children and young people with a low - grade glioma in the framework of a comprehensive overall concept, a current state of knowledge and best adapted therapy.
The study is ge - excluded since April 2012.