OC-009 Carbon-ion reirradiation for recurrent Head and Neck cancer: A single-institutional experience. (March 2019) - Held, T.; Windisch, P.; Akbaba, S.; Lang, K.; Bernhardt, D.; Plinkert, P.; Freier, K.; Kargus, S.; Rieken, S.; Herfarth, K.; Debus, J.; Adeberg, S.