Just want to comment that here at my local university center of excellence, a few days before my biopsy they had me come into the doctor's office for a quick "butt swab" (my technical term) for a bio analysis.
I suspect that's just to make sure i didn't have any antibiotic-resistant infection there, which might have affected their choice of antibiotics ( or something...)
The procedure itself, also trans rectal, really wasn't a big deal in my case, really just more some discomfort a opposed to actual pain. I suppose I might have preferred having had fewer that ten or so people in the room, but I guess that's part of it's being at a university hospital.
I just found it a little em-bare-assing.