The peculiar thing about BC @Bluebell5 is that ultimately it's a lottery and they just don't know why. But statistically speaking, 91% will still be truckin' five years after diagnosis. So no, don't write your will just yet.
My mother was diagnosed with aggressive breast cancer at 51, and it was in in lymphatic system. That was 1986. She still here driving me potty at 85!
I think it's impossible to truly relax with a cancer diagnosis, but don't panic if you can help it. Take care, and I hope you have a happy Christmas. K xox 🎅 🎄 🎁 😙