When I was diagnosed (via colonoscopy) I had a partially obstructing stricture. I had surgery first because of the stricture. I developed an obstruction while on chemotherapy. It required surgery again. They can put him on TPN (IV nutrition) so that he stays hydrated and nourished. Throughout my 7 month battle, I was almost always on a nothing by mouth diet (I couldn’t even have ice chips) because they needed my bowel to heal
I was very tiny but they kept my weight up by giving me 3,000 calories per day. I even did this at home once I was released.
Stay positive and keep asking questions