"The prep" is a bit unpleasant for a couple of hours, but no big deal. The actual procedure is done under propofol. Consider that part the best nap you will ever get.
You will either get a clean bill of health, or the doctors will find something that is easily treated right then and there. The stigma (especially of men) about this procedure will lead to countless numbers of them to die from something that doesn't have to be.
Get the procedure when your doctor says. Just do it. Please.
Unfortunately, they found quite a few polyps and one was large enough that a) the doc marked the spot with some dye and b) they cauterized it. The puff of smoke inside my gut was definitely the highlight for me.
I just found it totally fascinating to see my own insides live in in high res and listen to the doctor and nurses talk about what was going on.
In my case, I didn't want to be administered a powerful substance (and experience any lasting effects) unless absolutely necessary. My understanding is that adverse reactions are very rare, but if the only upside is avoidance of minor discomfort for 30-60 minutes, I don't see the point.
The trouble is exactly that it _can_ manifest early and it can become aggressive and that's when it's crucial to catch and treat.
I couldnt find statistical benefits of early diagnosis for internal cancers. The statisticians remove people from the counts if they die during treatment. So the 'early diagnosis' numbers were meaningless because they stop considering all the people in the original group.
However, for diseases like Hodgkins where we have what is in effect just a cure, albeit a fairly drastic one (I had Hodgkins in my mid-20s, I'm now in my 40s) clearly early diagnosis isn't just playing with the statistics. If I hadn't been diagnosed, they couldn't cure it, and then I'd almost certainly just be dead.
So the answer is it's complicated.
Which thinking do you not understand?