Sounds like what my grandmother had when my mom was 8. The cancer cells are basically liquid and leak down into the brain itself, so there's really nothing to do. Back then the doctors didn't know what it was, and just said she was crazy or on drugs, and didn't diagnose the tumor until it was way too late.
The father of one of my teachers in high school died of the same thing, and apparently brain surgery has not advanced that much in the last 40 years.
Really, really sad. Those hit home for me.