While gliomatosis cerebri can occur at any age, it is generally found in the third and fourth decades of life.

A case of gliomatosis cerebri presenting as rapidly progressive dementia and Parkinson's disease like symptoms was described in an 82 year old woman.

GLIOMATOSIS CEREBRI (WHO grade III) is a rare, diffuse glial tumor that infiltrates the brain extensively, involves more than two lobes, is frequently bilateral, and often extends to the infratentorial structures and spinal cord.