Among the 20 patients, 4 patients developed severe adverse events including one in the sdCRT group with an HPV-negative, p16-positive, p53-mutated retromolar trigone oropharyngeal squamous cell carcinoma within the radiation field 7 years after primary therapy; one from the sdCRT arm with osteoradionecrosis; one from the rdCRT arm with dental failure resulting in removal of all teeth; and one from the rdCRT group with severe oropharyngeal scarring and fibrosis. Here, TP53 is linked to osteoradionecrosis.