Perspectives of radiotherapy.

The 5 years' survival rate of all cancer patients is 35-45%. In that survival rate radiotherapy takes part in 15%. By further development of radiological methods and techniques radiotherapy gains significance in the recent time. Optimizing radiation planning and tactics, all modern imaging techniques are applied consequently. The radiotherapist must be able to asses their immanent specifity which should remain object of the radiological training, even if separated into therapy and diagnostics. Dose distribution is calculated by computer; three-dimensional planning is done in tumors of the mediastinum, oesophagus carcinoma and paraaortic lymphomas. Critical description of radiation techniques, results, problems and prognoses are given by results in tumors of the epipharynx and gastric cancer. After-loading, done until now only in gynaecological tumors, is performed in recurrences of pharyngeal tumors by individually shaped applicators. Reducing the number of therapy failures as well as possible, the application of higher tumor doses, new kinds of rays as neutrons and combinations with physical and chemical methods is outlined. Modifications of radiation volumes are discussed, especially the irradiation of the complete abdomen in ovarian cancer, the irradiation of the complete body surface by electrons in mycosis fungoides, and the total body irradiation prior to autologue bone marrow transplantation. Modifications of fractionation are shown in short-time radiation of bone metastases and single-time radiation of brain lesions. Low penetrating electron therapy facilitates intraoperative single-time irradiation. Because of higher biological efficiency neutrons and heavy ions allow to irradiate low sensible tumors or recurrences embedded in fibrotic tissue respectively. The combination with hyperthermia yields good results in tumors of the head and neck with better local response and total remissions of 59%. There are potentials in synchronising with chemotherapeutics. Remissions of different duration were achieved in 190 patients. Because of neutrotoxicity there are still problems in applicating radiosensitizers. New methods are applied treating endocrine active tumors by labelled hormone precursers.