Every time I've gone to the airport and had to use the body scanner, I've come up with weird chest results and they've had to give me a little pat down. I suspect it's from binding, but it was never an issue. I wore a sports bra last time I went so I can find out if it was due to binding, but they just used the metal detectors instead, so I didn't get an answer.
My packer I just decided to not risk it, so I put it in my checked bag or don't bring it, depending on how bad my dysphoria has been recently.