Top cancer dr wants to start 87 yr dad on 5-fu for 6 months b/c he says there are no side effects other than possible mouth sores & peeling skin. true?

Benefits VS risks: If your dad is very healthy 87 why not , should not deprive cancer treatments due age alone. If your dad is mentally incompetent , fragile , then family ( health proxy ) should decide with the advise from medical team. End stage of journey in this world , it is quality of life , not quantity is important , will make your decisions very simple.