~ diagnosis? ~ angry outbursts, memory and behavior issues

Hi everyone. A friend of mine has been struggling with his wife - memory, behavior, etc. - for a few years now and it's gotten progressively worse. She's had angry outbursts toward him, both physical and verbal. He has taken her to all the doctors in our area from Psychiatrists, to Neurologists, to Neurosurgeons, and all they can tell him is that she has a very rare brain disease which affects both the frontal and lateral lobes .... there is no cure. It apparently isn't Alzheimers.
We live very close to one of the top hospitals in the country and after waiting months he was able to get an appt. for her to be seen. It will be an all day session, but they have been assured they will have a diagnosis for them, and what lies ahead for her.
Does anyone have any idea what this is? It's been very hard for him to deal with and I know that when they at least have a real diagnosis, while it won't change anything, they will at least know.
Any input would be greatly appreciated.
Barb