Adaptive RadioTherapy for OroPharynx Cancer

This is a phase II randomized trial, where patients with histologically proven squamous cell carcinoma of oropharynx that have primary tumor (T3 - T4) in place, treated with curative intent chemoradiation, will be randomized to systematic mid-treatment MRI-based radiotherapy adaptation vs. standard of care. The primary objective is to compare patient-rated dysphagia (as assessed by the MD Anderson Dysphagia Inventory composite score at 6 months post-treatment in patients undergoing routine mid-treatment MR-guided radiotherapy adaptation vs. in patients receiving the current standard of care.

Inclusion Criteria: * Age ≥18 years * Ability to provide written informed consent. * Stage T3-T4N0-3 as per AJCC 8th edition * Eastern Cooperative Oncology Group (ECOG) performance status 0-2. * Biopsy proven diagnosis of squamous cell carcinoma of the oropharynx. * Planned for curative radiotherapy +/- chemotherapy * For females of child-bearing age, a negative pregnancy test * Patients treated with induction chemotherapy can be included if they have residual tumor in place. Exclusion Criteria: * Previous irradiation of the head and neck (HNC) region, excluding superficial radiation therapy for non-melanomatous skin cancer * Previous surgery of the HNC region (except for incisional or excisional biopsies) * Pregnancy or breastfeeding * Connective tissue disease * Any medical condition that could, in the opinion of the investigator, prevent follow-up after radiotherapy. * Patients with contra-indications to MRI will be excluded.