I have lived a somewhat careful life and here I am on this website.
As far as I am concerned 'they' can do whatever research they want and come up with answers for the distant future for someone we will never know but for me, I am now living how I want, having what I want and doing what I want BECAUSE I may die tomorrow in a car accident or I may die in the future from a recurrence of the BC. Who knows ?
Do what you think is best for now and just hope the future supports your decision.
If not, what will be will be and those left behind WILL cope.
Anne