What cumulative dose would you allow the pharyngeal carotid to receive for a course of reirradiation for a retropharyngeal node?

No dosimetric data available. I don't use a carotid OAR in my cases, and just ensure the disease is appropriately covered, while limiting cord/brainstem primarily.

From the literature, highest risk cases are those with skin involvement (ie tumor from skin to carotid). Risk of 1-5% for carotid blowout...

I agree--there is no established dose. I have also previously discussed the matter of attempting to spare the carotid with disease that is subjacent or encasing the major vessel. The vast majority of the data in the publications from UPMC, including the multi-institutional review (MIRI), did not spa...