how do people with oral cancer die? from pain?

Answer 1

Many of my oral cancer patients died from either pneumonia or hemorrage. As you know, the floor of the mouth, tongue, and throat are rich in blood vessels and lymph nodes; that's why it is almost impossible to cure and it spreads throughout the neck. Most patients end up with a tracheostomy, VERY thick secretions, and a very vulnerable airway (hence, the risk for pneumonia).
My heart bleeds for whomever it is dealing with this horrible illness. Sorry I can't be of more help.

Answer 2

It varies. Maybe the tumor will make your mouth / throat so they don't work (or hurt too much), and you can't eat or drink, and you die (unless your get a feeding tube, inserted near the belly button). Or maybe the tumor spreads to vital organs and kills you.

I don't think pain will kill you exactly.

Maybe the treatment will kill you. If the cancer is really bad, then the treatment can be pretty harsh.

Or, of course, you can get treated and cured and live a long and healthy life ever afterward. For me (I'm a cancer survivor), so far so good.