Astrocytoma
An astrocytoma is a primary central nervous system (CNS) tumour that is typically located in white matter. They arise from astrocytes and are the most common glial tumour.
They are divided into:
- diffuse astrocytoma or low grade astrocytoma : WHO grade II (10 - 15% of astrocytomas)
- anaplastic astrocytoma : WHO grade III (25% of astrocytomas)
- glioblastoma multiforme : WHO grade IV (50 - 60% of astrocytomas)
A number of other astrocytic tumours also exist, although they are usually considered separately. These include:
- pilocytic astrocytoma : 9421/11 - WHO grade I
- pilomyxoid astrocytoma : 9425/3* - WHO grade II
- subependymal giant cell astrocytoma : 9384/1 - WHO grade I
- pleomorphic xanthoastrocytoma : 9424/3 - WHO grade II
Additionally some tumours also contains astrocytic components, and it is often this component that dictated biological behaviour. Examples include:
