PET/CT Assessment of Radiation-Induced Vascular Complications in Head and Neck Cancer

PRIMARY OBJECTIVES: I. To determine the role of FDG- and NaF-PET in assessing radiation-induced vascular complications by comparing baseline and follow-up scans in patients with head and neck cancer. II. To assess the presence and extent of radiation-induced vascular inflammation following proton versus (vs) photon radiation therapy (RT) in patients with head and neck cancer. III. To determine the correlation between inflammation and actual radiation dose received to the vasculature to assess the effects of dose response. SECONDARY OBJECTIVE: I. To determine the effect of radiation-induced vascular inflammation (possibly atherosclerosis) on global brain function as measured by FDG-PET. OUTLINE: Patients are assigned to 1 of 2 arms. ARM I: Patients receive F-18 NaF intravenously (IV) and undergo PET/CT within 28 days of each standard of care (SOC) F-18 FDG PET/CT on study, once prior to initiation of SOC intensity-modulated radiation therapy (IMRT) and once 12 weeks after completion of SOC IMRT. ARM II: Patients receive F-18 NaF IV and undergo PET/CT within 28 days of each SOC F-18 FDG PET/CT on study, once prior to initiation of SOC intensity-modulated proton therapy (IMPT) and once 12 weeks after completion of SOC IMPT. After completion of study intervention, patients are followed up within one to five business days.