Why did they do radiation if the cancer was just suspected in that node?

I guess I don't understand why they do the radiation like a normal head and neck cancer that has no known origin in your mucosa??

Pet scans will show where the suspicious areas are.

Guide me as I have the same type of node going on that has not gone down after a run with antibiotics, although I am acknowledging that my teeth do hurt, and I many have a cavity/abcess by the node.

Seeing a dentist tomorrow.

Thanks for all of your input. As a nurse this tends to scare me a bit. I am aware of what doctors miss and assume sometimes.