It’s worth noting that the surgeons who do top surgery and the surgeons who do mastectomies or reconstruction for breast cancer often aren’t the same people (on top of that, I believe it’s common for the person doing the actual “cutting out cancer” part and the person doing the reconstruction to be separate people)–they’re fairly distinct medical communities. This may be changing a bit in the US now that there’s insurance coverage for top surgery, but they’re still pretty different worlds, afaik. (I actually knew someone who had discovered he had breast cancer as he was preparing for top surgery. It did upend the plan somewhat, but he happened to be seeing a surgeon who actually saw cancer patients, so it was less disruptive than it could have been. I suspect the surgeon I saw would have said “yeah, sorry, can’t help you”.)