Using Magnetic Resonance Imaging (MRI) to Assess Mandibular and Soft Tissue Responses to Radiation Therapy

Inclusion Criteria: * Willing and able to provide informed consent * Patients must have histologic evidence of malignant neoplasm that may have been obtained from the primary tumor or metastatic lymph node * Receipt of external beam radiation therapy (EBRT) with curative intent, with or without concomitant chemotherapy * Good performance status (Eastern Cooperative Oncology Group \[ECOG\] score 0-2) * Willing to comply with all study procedures; and * Willing to participate for the duration of the study * COHORT 1 (LONGITUDINAL) GROUP 1 (PRE-RADIATION): Subjects who are currently undergoing or scheduled to undergo treatment with radiotherapy with or without chemotherapy (induction or concurrent) with intent to eradicate the malignancy. Treatment will include the following: 1) primary or nodal disease adjacent to (within 2 cm) the mandible (i.e., likely to receive a dose of at least 50 Gy to some portion of the mandible volumes) and 2) \> 60% probability of survival for 3 years after treatment * COHORT 1 (LONGITUDINAL) GROUP 2 (POST-RADIATION): Subjects who were previously treated with radiotherapy with or without chemotherapy (induction or concurrent). Treatment will have included the following: 1) unilateral maximum mandible dose of \>= 60 Gy and a gradient of dose across the mandible of \>= 20 Gy, 2) oncological cure and now in disease surveillance; and 3) no clinically diagnosed ORN at the time of enrollment * COHORT 2 (ENRICHED): Subjects with recurrent and/or new head and neck cancer disease who will undergo re-irradiation to the head and neck with intent to eradicate the malignancy. Treatment will include the following: 1) any mandible dose of at least 50 Gy cumulative (initial and subsequent treatment); and 2) no clinically diagnosed ORN at the time of enrollment * COHORT 3 (EARLY ORN INTERVENTION): Subjects with clinically confirmed low-grade/early stage osteoradionecrosis requiring therapeutic (medical and/or dental surgery) intervention as diagnosed by a qualified clinician. Clinical staging of developing or existing ORN will be conducted using the CTCAE 4.0 (Common Terminology Criteria for Adverse Events) * COHORT 4 (SURGICAL INTERVENTION FOR ADVANCED ORN): Subjects with clinically confirmed high grade/high stage osteoradionecrosis requiring surgical intervention. Clinical staging of ORN will be conducted using the CTCAE 4.0 (Common Terminology Criteria for Adverse Events) Exclusion Criteria: * Unable to tolerate diffusion weighted (DW)-MRI or DCE-MRI * Having an estimated glomerular filtration rate (GFR) \< 60 ml/min/1.73 m\^2 * Contraindication to MRI (e.g. non-MRI compatible metallic implants) * Pregnant females and cognitively impaired patients * Unable or unwilling to give written, informed consent to undergo MRI imaging * Claustrophobia * Unable to obtain imaging studies of adequate quality to assess imaging-based biomarkers * COHORT 1/GROUP 1: Previously treated with radiotherapy for a malignant neoplasm of the head and neck, excluding cutaneous lesions. Determination will be made by review of the radiation therapy plan and dosimetry map to evaluate mandible exposure to radiation * COHORT 1/GROUP 2: Previously treated with radiotherapy for a malignant neoplasm of the head and neck more than one time, excluding cutaneous lesions