Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Gliomatosis cerebri ?
    ### Response:
    Gliomatosis cerebri is a type of brain cancer.  It is a variant form of glioblastoma multiforme. It is characterized by scattered and widespread tumor cells that can cause the cerebrum, cerebellum, or brain stem to enlarge. Signs and symptoms may include personality changes, memory disturbance, headache, hemiparesis, and seizures.
    