Hello
I am sorry to hear about your father. Remission is always possible regardless of the stage. The issue with remission is that it can come back and that is more likely with later stage cancers. I would not give up hope. Brain mets are not as dire as they were once thought to be. The doctor of course is going to give you the worst scenario. Good luck and dont give up hope yet. I do know of some stage 4 people who did go into remission with their treatment.