As is so often true, there is no absolute answer to a general question of this sort.  It is much less common nowadays for a patient to be medically inoperable with the major advances in anesthesia.  That being said, these patients certainly do appear. There is not a good literature on the ...

7 years after this answer, for a middle aged female with T4 anal canal adenocarcinoma due to sphincter and vaginal invasion, excellent PS and complete response, and good sphincter function following induction chemo who refuses APR, do we still agree with 60 Gy total dose? What is an appropriate GTV-...