I can sort of see both sides of the argument and I think I vaguely recall my Dr asking did I have a will as it can be a long drawn out thing fighting cancer and I didn't need to be worrying about legalities while I was being treated.
I did have a will so it wasn't an issue but throughout life we do get little wake up calls and should address those sorts of things early, before we are pumped up full of painkilling drugs. I think even in the hospital forms there was a do not resuscitate section to fill in if I wanted it. Breast cancer can be a very serious thing and although many of us (89%) do survive 5yrs or more, we need to be mindful of the other percentage that don't. They cannot comment on this forum.