<unk> s are largely glioneuronal<unk> s, meaning they are composed of both glial cells and neurons. Three subunits of<unk> s have been commonly identified: * Simple: Specific glioneuronal elements are the sole components of simple<unk> s. * Complex: Glial nodules and/or type 3b focal cortical dysplasia (FCD), in addition to the glioneuronal elements are present in complex<unk> s. Both the nodules and FCD can be present within the same<unk> , though only 47% of complex<unk> s are linked to FCD. * Nonspecific: Nonspecific<unk> s are lacking the glioneuronal elements common to<unk> s but will show glial nodules and/or type 3b FCD. Eighty-five percent of nonspecific case of<unk> s show this FCD. There currently exists some debate over where to make the proper division for the subunits of<unk> s. A fourth subunit is sometimes noted as a mixed subunit. This mixed subunit expresses the glial nodules and components of ganglioglioma. Other findings suggest that<unk> s require a reclassification to associate them with oligodendrogliomas,<unk> s that arise from solely glial cells. These reports suggest that the neurons found within<unk> s are much rarer than previously reported. For the neurons that are seen in the<unk> s, it is suggested that they had been trapped within the<unk>  upon formation, and are not a part of the<unk>  itself.
Dysembryoplastic neuroepithelial tumour
Neurothekeoma
Primitive neuroectodermal tumor
Extracranial germ cell tumor
Glial tumor
Sialoblastoma
Central neurocytoma
Pediatric ependymoma