De-escalation with Definitive Unilateral Neck Radiation for T3 or N2b/N3 p16+ Tonsil Squamous Cell Carcinoma Using Prospectively Defined Criteria

American College of Radiology recommends unilateral neck radiation (RT) for small lateralized tonsillar cancer with low-volume nodal disease. Safety of unilateral RT for larger primary or advanced nodal disease remains to be explored but provides an important opportunity for treatment de-escalation. We report oncologic and functional outcomes of patients with advanced-stage p16+ oropharyngeal cancer treated with unilateral RT using prospectively defined criteria.