Gliomas are brain tumours that are composed of cells that appear to be a proliferation of glial cells (that is, astrocytes, ependymal cells and oligodendrocytes). They are the most common type of primary brain tumour. These tumours are not malignant in the sense that they do not metastasize outside of the central nervous system, however as they grow and invade they can cause significant disability depending upon what parts of the brain they are damaging; ultimately they often prove fatal. In the palliative care context the high-grade gliomas such as glioblastomas are the usual gliomas seen
The clasification of brain tumours has changed and evolved over the years. The current standard classification is based on the 2007 World Health Organization classification which is shown in the table below.
|Astrocytic cells||Pilocytic astroytoma||I|
|Glioblastoma with oligodendroglioma component||IV|
|Ependymal cells||Subependymoma and myxopapillary ependymoma||I|
|Table: Glioma Classification|
The prognosis is quite variable depending on tumour type. The distinction between grades is particularly helpful in informing prognosis with the grade IV tumours having a particularly poor prognosis. In general, oligodendrocytic tumours have a better long-term prognosis than the astrocytic tumours of the same grade. The prognosis of ependymal cell tumours is particularly related to the location of the tumour.