96 year old right colon mass....surgery???

My 96 year old mother has a tumor in c-type shape around cecum. She had a colonscopy and no other growths were found. Symptoms were combination constipation and loose stools, but has been in relatively good health otherwise. She has lived independently in her home with wheelchair assistance until three weeks ago when hospitalized with the above symptoms that had become difficult to control. Mentally she is 100%, but is undecided on whether she should proceed with surgery to remove tumor. Family doctor is in the opinion that if tumor is left, it will eventually cause a blockage that is a difficult and painful way to end life. She has flew through the pre-op tests with no problem! Is surgery like this for a 96 year old something often done? My mother and family are turning this decision over and over. Family doctor tells us if it was his mother, he would advise her to have the surgery and risk death that way rather than risk of blockage/death. We are so conflicted - any thoughts or insight would be appreciated.