Here is part of my reply to another thread on a similar issue:

This is quite a tough decision and very much on the edge of current debates on rectal/colon cancer treatment. I have had many conversations about this with both onc surgeons and onc chemo docs. The main study they all use is the OPRA study from MSK. (https://www.mskcc.org/clinical-updates/rectal-cancer-response-to-total-neoadjuvant-therapy-predicts-organ-preservation-and-survival-outcomes).

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There are a number of factors that drive a person's "eligibility" for watch and wait detailed in the study, including all negative scans, and tolerating very aggressive surveillance. For me, its a 3 month rotation of CT, MRI or sig flex so I have something just about every month. I also have the Natura blood test that took a DNA sample of my tumor, then tests for that in my blood. I was positive when I presented, has been zero for moth than 18 months now.

My surgery, if we did it, was intended as a reversible stoma (3 - 6 months). My tumors were a bit higher in the sigmoid area, not low, which makes the procedure not as tough in terms of recovery.

My next sig flex is the end of this month. Every time we worry. With the surgery/bag, you might not worry as much for each test. The surgeons want to be sure the patient losing part of your rectum but has no sign of disease on pathology is a "success."

I did have CRR, and CPR on all my scans, with no sign of disease.

My last treatment was radiation/chemo Feb of 2024.

Very hard choice. My doctors told me "Five to ten years from now we will probably have a test to sort who is best for W&W and who is not. Right now we might be over-treating a lot of people, but we can't predict outcomes and risks well enough."

They "recommended" surgery for me, but also indicated W&W was an option. That is what I am doing now.