[Incidence of osteoradionecrosis after combined radiotherapy-chemotherapy of head and neck tumors].

Combined modality therapy, consisting of radiation, chemotherapy and surgery are used to treat primary tumours aiming to preserve function and increase tumour control. In the present prospective trial 112 patients underwent combined preoperative radio-chemotherapy, 35 patients were treated with combined radio-chemotherapy as only treatment. At a median follow-up of 26 months eight patients (2.8%) have developed an osteo-radionecrosis, which is comparable with data from the literature. When known risk factors are avoided the incidence of osteo-radionecrosis is not increased following combined therapy. The most important factors for development of osteo-radionecrosis following radio-chemotherapy are large tumours and tumour infiltration in the mandible.