I've dealt with 3 people that were/are close to me having cancer.
Two were my ex in laws and they died from it, recently. They also refused treatment, because they believed it was their time to go.
My aunt is the third. The mass was removed and she has remained cancer free.
I've had cancerous cells removed twice from my cervix. Once when I was preggo with my youngest. I had premature labor 3-4 times after that.
My opinion is if I were to ever get cancer that would require treatment, I'd go through with it for the sake of my kids. I wouldn't want them to have to deal with the pain of losing their mom so suddenly and so young. If I were going thru the treatment, at least they could somewhat prepare for what could be my death.
I think it's sad to not give them a chance to prepare if I could.