I am here on this forum again after 17 years with a heavy heart.
In 2009 my mother (then 43) was found to have a stage IV cancer of the palate with some spread to the lymph nodes, which was treated with radical neck dissection and then radiation.
In the period since, she has suffered from impaired speech, impaired hearing, trismus, been reduced to soft bland food, lost most teeth and has gradually deteriorating oral conditions. But -- and we are grateful -- she has been cancer free.

This year, a new ulcer has appeared on the side of the tongue extending into the base, on the opposite side of the mouth to the original. It is diagnosed as SCC and has not spread.

The surgical option would require full tongue removal, going through the jaw bone, windpipe reattachment, and tongue reconstruction with tissue from the thigh. She would lose speech completely and need to use a gastrostomy tube for the rest of her life.
My mother is obviously mortified at the prospect of going through something like this again, and the team at our cancer hospital thinks the morbidity of such a surgery would be very high. All her life she has been the person taking care of everyone else, us and our children. It also bothers her a great deal to find herself dependent on others.
Considering our own reluctance towards surgery, we have been proposed a combination of chemotherapy (12mg/m2 of Docetaxel - to avoid further hearing impairment from Cisplatin) and Proton radiation (aiming to avoid brain stem and spinal cord).

We got a remote 2nd opinion with a prominent UK surgeon and he was confident this new primary is caused by the first radiation therapy, and that in such cases the tumour does not respond well to irradiating again. He believes that the chemo-radiation option will therefore not be curative, and she would end up with a feeding tube anyway. That makes it look like the option we were heading for is not an option at all -- significant side effects with little chance of a cure.

It would be most helpful if someone has experience to share from either of these pathways. I do appreciate everyone's case is different but getting some idea of the human side of this condition would perhaps give her clarity.

Wishing good health to all.