My maternal grandparents died of brain cancer will the same thing happen with me?

My mother's dad had brain tumours and died of brain cancer he use to behave insane in his last days my mother says he was diagnosed with schizophrenia.
Same for her mother, she didn't have schizophrenia but died of brain cancer.
That's when I was very very young.
Some of my close old relatives say, even my great maternal grandmother was mental in her last days and she killed herself because she couldn't bare headaches.

I think I'm totally fine but I'm always worried that I'll die in the same way maybe because I might have inherited that.