Here's my point of view, from what we did.
First I had substantial family history with CRC and was aware of important "first aid" plans for CRC and CRC surgery. Decisive actions that started best on Day 1 or during the first week. (see Day1, Week1 post in the link at the bottom)
We did those with great benefit. It was a lifesaver for my wife.
Second, there were substantial inefficiencies that made timely information difficult, confused, confusing and slow - taking a year to uncover stuff or bits to dribble in. The biggest keys for us were in missing blood data, that done best, needs to start close as possible to diagnosis. Mistakes get made, and better data can help you see, stop and recover from them. Better data can remove or narrow unknowns and uncertainties, and create opportunities.
Some of the data is irreplaceable and will be lost if you don't get it now. Some of the data may or may not be irreplaceable. I have observed that if time is short before first treatment, surgery or radiation, the best data coverage is to self- order additional blood tests now if the drs haven't already ordered them. I often wonder how many patients suffer or die because they waited on their doctors or insurance to approve something of minor cost.
initial blood tests before surgeryThird, get a board certified colorectal surgeon.
Fourth, if things look bad, don't panic. Read, research, think and plan as much as possible. Extra money spent wisely the first weeks and year can pay great dividends. Hold on to a cash reserve, try to avoid spending too much in one place.
Fifth, ask questions and consider second or multiple opinions from different kinds of drs.
Here's a prior version of this discussion with links
Checklist and Day1, Week1