What dose and treatment area of radiation should be given when p16+/HPV ISH negative SCC is found in the scar of a level V lymph node excisional biopsy with all other workup negative?

It is difficult to give a detailed and nuanced response in one sentence. I would double-check that this is also EBER-negative, and if so, I would suspect a non-HN mucosal primary, possibly skin (as these can be p16+ve HPV -ve). As such, I would focus treatment on the involved neck. It sounds like, d...

Assuming negative, esp mucosal, workup and no identifiable skin primary, but a pattern most consistent with an occult cutaneous SCC (esp with any h/o prior skin cancer), I would focus treatment on the ipsilateral neck. I’d treat the level V tumor bed (including the scar) with a bolus to a dose of 66...