Brief Answer:
probably palliative treatment

Detailed Answer:
Hi
Thanks for your query.

It is true that the disease is quite advanced and patient quite elderly. I understand that surgery already done, but I am not sure if radiation therapy was done or not.

If radiation not done then can be considered now along with Targeted therapy called cetuximab.

If radiation already done, then chemotherapy with cetuximab. Exact medicines and doses can be fixed by treating medical oncologist.

If patient unfit for all of above then only symptomatic treatment is appropriate.

Hope this helps.
Regards

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