[Principles of radiation therapy for malignant tumors of the orbit and the periorbital area].

Primary malignant tumors of the orbit and the orbital adnexal area are rare, variform and in the majority of cases need an interdisciplinary treatment. According to tumor entity, tumor localization, and tumor extent the complete spectrum of radiotherapeutic therapy options is necessary. In the majority of malignant tumors, such as those of the eyelids, lachrymal glands, orbit, metastases, sarcoma or lymphoma, radiotherapy is used as a high energy therapy by means of medical linear accelerators as so-called teletherapy. In addition, new therapy methods, such as stereotactic highly conformal radiation or intensity-modulated radiation therapy (IMRT) were developed to achieve a higher local tumor control by a better configuration of the radiotherapy fields to the tumor borders and to contribute to a reduction of acute and chronic side effects in normal tissue by blurring of the dose. The application of ionizing radiation sources, such as so-called interstitial brachytherapy can also be just as carefully as effectively used. Particle beam radiotherapy is limited only to specially licensed centers and light hydrogen ions as proton therapy or carbon ions as heavy ion radiotherapy are in use. This overview will show the options as well as important progress in the field of radiotherapy in the treatment of tumors of the orbit and periorbital area.