Dysmae, Sorry to have you among us. You must be feeling overwhelmed. Somehow a cancer diagnosis tends to stun people first and foremost. That will pass. You must educate yourselves - the more you know, the better the chances your son will beat this and live to be an old man.
Cathy mentioned that oral cancers are often aggressive. This is true. There are so many complicated structures in and around the mouth, that cancer has way too many places to hide. And I agree that it is REALLY important to talk to docs who treat this particiular type of cancer regularly - its a bit different.
The best docs are really aggressive with treatment - they "pull out all the stops" when prescribing for head/neck cancers. Hit it early, and hit it as hard as possible. Those of us who have had aggressive treatment are still here to tell the tale.
The treatment can be very tough, though we each experience it differently. Chemo and radiation are scary, but very manageable. Most of the 'scary' for me was helped with knowledge - the better informed you are, the fewer surprises you get. Most of us are quite a bit older than your son, so if we can do it, I'll hunch your son can too.
Get more than one opinion. Always. Read about oral cancers here on this site. Ask lots of questions when with the docs. Don't let them minimize your questions or concerns - make them defend the decisions they are making - why this treatment? why this drug? etc. Always ask to be told about all other options. Be a smart consumer and be tough to pursuade about everything. It keeps them on their toes, and it gets you better informed - both are critical.
Don't listen to the "odds". Ever. Make your own odds. Let the scared wash over you, then get mad, get informed and get aggressive. Don't let the beast win. This disease can be beaten. We have done it and we are many. Come to this forum often with questions and worries. Get your son on here too. Let us help. Be strong. Tom