a groove

So, I've had this poop groove since prior to Dx and assume that it was the tumor. But I still have it. First, let me say that I feel confident that the tumor was "killed" and that my cancer is cured. I'm not even worried about it and will have biopsies when the time is right just to satisfy my gastroenterologist's curiosity (and conversely, won't have a PET scan because the risk/benefit analysis --mine-- has led me to that decision.) So the thing is, I'm curious about this groove, though not alarmed by it. Has anyone had this groove prior and post treatment? (most importantly, post).