In what situations, if any, would you recommend adjuvant concurrent chemoradiation rather than RT alone?

I think think this is head and neck cancer? Cannot tell based on the question.

1. Positive margins from an oncologic surgery (i.e., simple tonsillectomy with positive margins does not buy you the juice).
   
   
2. Any pathologic ECE in the lymph nodes. I don't differentiate between focal and diffuse.
   
   The origin...