Colon cancer in 89 year old

My 89 year old mum has just been diagnosed with colon cancer.  CT scan doesn’t show signs of spread so doctor has indicated they may be able to remove part of her bowel and rejoin it, leaving her with a stoma. will all depend on further tests to see if she is physically up to the operation. 

 it’s a big operation for someone her age and she can’t decide what to do.   Would be really good to understand risks of this being auccessful but also the experience of others who know people who have had this op at an advanced age. 

and if she doesn’t have it, what does her future look like?