In my experience among friends and acquaintances who were diagnosed with glioblastoma the life expectancy is in the 4 month range. In two months, all I’ve known were bed ridden with a morphine pump in hand. At some point after that, hospice will remove the regulation on the morphine and the patient can punch out anytime after that.
Survival rates are less than 4%.
John McCain faces a very grim reality. My advice to the Senator would be go home and spend his few remaining good days with his family.
That was certainly the way it went with a good friend of mine. There is no way out of this and his time is almost certainly very short.