It is worht pointing out, though, that they can't know for sure the nodes are not involved without removing them. There's something like a 30% chance that you can have cancer in one or more nodes and it won't show up on a CT scan. That said, I agree with everyone else that it seems like the standard for BOT os to treat first, with radiation and chemo, and then, maybe, do a neck dissection to be sure the nodes are clean.

Is it possible they just want to do the neck dissection first, not operate on the tongue?