[Radiotherapy: principles and application with special attention to the head and neck region]

Radiotherapy plays an important role in the treatment of cancer and is often applied with curative intent. With the help of modern technical equipment irradiation can be delivered at the tumour localization with maximal sparing of the surrounding normal tissues. Also can differences in the biological effects of irradiation between tumour and normal tissue be utilized to optimize treatment by increasing the chances for cure while limiting side effects. The complex anatomy of the head and neck requires that irradiation is delivered with high precision. Intensive support of the patient before, during, and after treatment is of great importance to control side effects.