Pediatric brain tumors are generally classified depending on the cell type and location of origin in the brain.
The brain is composed of two main cell types:
- Neurons
- Glial cells
Both arise in early development from primitive neural ectoderm.
Most pediatric brain tumors are gliomas or blastomas, and thus will contain these terms in their names.
The majority of primary brain tumors arise from glial cells and are broadly termed “gliomas.” Gliomas can be further divided as by glial subtypes:
- Astrocytes (astrocytoma)
- Oligodendrocytes (oligodendroglioma)
- Ependymal cells (ependymoma)
- Microglia
Blastomas are malignant tumors whose cells have undeveloped or embryonic characteristics.
The following is a generally accepted classification scheme for pediatric brain tumors:
Histopathologic classification of CNS tumors- WHO classification 1994:
| Tumor Origin | Tumor Cell Type |
Tumor Examples |
Tumors of neuroepithelial tissue
|
Astrocytic tumors |
|
Oligodendroglial tumors |
|
|
Ependymal tumors |
|
|
Choroid plexus tumors |
|
|
Neuronal tumors |
|
|
Pineal tumors |
|
|
Embryonal tumors
|
Primary neuroectodermal tumors (PNETs) |
|
Other embryonal cells |
||
Germ cell tumors
|
|
|
Tumors of the sellar region |
|
|
