Maria, I am sorry to read of your mothers struggles with oral cancer. Ive had my lower jaw removed so I do know how difficult it is to recover from a big surgery like what your mam has had.

Without getting clear margins it is possible that a teeny-tiny cell was missed which could bring back the cancer. Radiation is not easy to go thru but it can be done. Ive seen several older patients get thru radiation and go on to lead productive lives. Im sure your mom is worn out from what she has gone thru. If she chooses to not go thru with radiation then she has a much higher risk of having a recurrence. Oral cancer is a fast moving cancer. If it returns and is not found right away, it could be fatal to your mother. The best advice I can give you is if you are not comfortable with the doctors options that he suggested, get another opinion. This is a very difficult decision to make but ultimately it is up to your mother weather she wants any further treatment or not.

Hope this info has been at least a little helpful to you. Best wishes with this decision.