The most effective approach to reducing acute toxicity after radiotherapy is to cut out healthy tissue from the radiation field. GWR can increase the distance between the tumor and normal tissue. Even the smallest geometric changes lead to a significant dose reduction in normal tissue and significant advantages for the patient. Adequate immobilization also reduces unwanted movements, especially of the tongue.

The GWR are manufactured as combinable modules according to the "modular principle". This improves reproducibility and flexibility and reduces development and manufacturing costs. The study is being conducted as a monocentric, prospective, randomized phase II study. A total of 34 patients who meet the inclusion criteria are examined for acute toxicity after radiotherapy of a malignant head and neck tumor. The primary goal of the study is to reduce acute toxicity through individual immobilization of the jaw and tongue. Secondary study goals are the evaluation of quality of life and long-term toxicity as well as local control and overall survival twelve months after radiotherapy. In both groups, radiation therapy is carried out in accordance with guidelines using image-guided radiotherapy.