Intensity modulated radiotherapy (IMRT) of head and neck tumors. Increased biological effectiveness in high-risk situations by "Integrated boost" therapy

Primary tumors of the paranasal sinuses are rare entities which, because of precarious localization and frequently diffuse propagation into neighbouring cavities and the skull base, pose a significant therapeutic problem. Even after complete surgical resection, local relapses are frequent. Postoperative radiotherapy is therefore usually indicated. Intensity modulated radiotherapy (IMRT) is a new technique that helps creating dose distributions that conform closely to the target volume while maximally sparing the organs at risk. This results in the possibility of applying escalated doses to the target while still keeping the incidence of side effects low. What is especially appealing is the possibility of shaping the dose distribution within the target in such a way that areas with a presumably high tumor cell load receive increased doses, a concept which is best described by the term "integrated boost" We present the case of a patient with a sinunasal carcinoma and describe the implications of the clinical implementation of this technique.