Luigi,
I had oral cancer in lower left jaw in Oct 2000 (T3N1M0 ) and also had 15 lymphs removed during op, of which one was cancerous. I had to decide whether to have radiotherapy, as they had booked me in a specialist unit for 2 weeks to have the treatment. After talking to my surgeon about it, and others, I decided to say no to the radiotherapy, and have fortunately been OK ever since. Good luck.
AJ