Phase II Study of Daily Adaptive Radiotherapy for Submandibular Gland-sparing in Head and Neck Cancer

Inclusion Criteria: * Age ≥ 18 years * Histologically proven Squamous Cell carcinoma of head and neck * Bilateral neck being treated * At least one level 1b not being treated electively and with no target structure, other than elective level II/III, \<1cm to spared SMG * ECOG PS 0-2 * Planned for curative (chemo)radiotherapy * Able to receive and understand verbal and written information regarding study and able to give written informed consent * Be able to lie comfortably on back and to wear immobilization for up to 1 hour Exclusion Criteria: * As judged by investigator evidence of systemic disease that makes unsuitable for study * Pregnancy * Underlying salivary dysfunction prior to treatment judged by investigator to affect likelihood of benefit from ART