The presence of a glioma, which is a neoplasm of the central nervous system originating from a glial cell (astrocytes or oligodendrocytes).
Comment:
Gliomas can be classified as 1) ependymomas, 2) astrocytomas (including glioblastoma multiforme), 3 oligodendrogliomas, and 4) mixed gliomas, such as oligoastrocytomas.