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Radiotherapy is generally accepted as a standard treatment for early-stage testicular seminoma. Relapse rates of 2% to 5% in clinical stage I and 10% to 20% in stage IIA/B (according to the Royal Marsden classification) can be achieved. Disease-specific survival reaches 100%. With such excellent cure rates, treatment-related side effects gain particular importance. Therefore, a prospective multicenter trial was initiated for radiotherapy of testicular seminoma with limited treatment portals and low total doses of irradiation. In clinical stage I, 483 patients were treated with 26 Gy to the para-aortic region only. In stage IIA, 42 patients and, in stage IIB, 18 patients received irradiation to the para-aortic and high iliac lymph nodes with 30 and 36 Gy, respectively. With a median time to follow-up of 55 months for stage I and 55.5 months for stage IIA/B, there were 18 (3.7%) and 4 (6.7%) cases of relapse in both treatment groups. Disease-specific survival was 99.6% in stage I and 100% in stage IIA/B. Acute toxicity was dominated by moderate gastro-intestinal side effects. No major late toxicity has been observed to date. Limited volume pure para-aortic treatment for stage I and para-aortic/high iliac irradiation for stage IIA/B with 26, 30 and 36 Gy, respectively, yields excellent cure rates with only moderate acute toxicity and is therefore recommended as standard treatment.

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Medical imaging procedures are providing qualitative and, increasingly, quantitative diagnostic information on the morphology and function of the human organism. As possibilities for communication and data processing continue to grow, they are also being applied in the field of therapy. Taking combined local radiotherapy and thermotherapy for the treatment of uterine carcinoma as an example, this paper describes the integration of the biological-pathological situation into the modelling of isothermal profiles using the patient's image data.

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This paper describes a new type of applicator system for the intracavitary radiothermotherapy of gynaecological tumours. Hyperthermia and radiation can be delivered by one and the same applicator. The hyperthermia is delivered by a modified capacitive heating technique (27.12 MHz) combined with cooling systems, the radiation by the numerically controlled oscillation of a gamma source on the inside of the main applicator, the RF gamma applicator (HDR afterloading technique). Isotherms and isodoses can be adapted to the anatomical-pathological situation. Interactions between the applicator system and the surrounding tissue were investigated in a theoretical model (FEM). Complex two-dimensional SAR calculations as well as three-dimensional temperature calculations were carried out. The RF gamma applicator was also examined by thermography; the thermography proved the theoretical modelling to be correct. The applicators were also tested in animal experiments.

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An applicator system for the radiothermotherapy of gynecological tumors has been developed. The concept is based on combining high-dose rate afterloading therapy with local hyperthermia (27.12 MHz). The main applicator, the rf-gamma applicator consists of a guide tube for the gamma source, an electrode system and a cooling system. Isodoses and isotherms can be adapted to the individual anatomical-pathological situation presenting. For therapy planning the interaction between the applicators and the perfused tissue was investigated in a theoretical FEM model. In the first step, the SAR-function in the vicinity of the rf-applicator was determined by means of a 2D FEM calculation. In a second step, the 3D temperature fields was determined using linear shape functions. The results of these calculations showed that in every case the hot spots shifted from the applicator surface into the depths of the tissue. With the aid of an infrared camera and a split phantom the calculations were examined in a homogeneous non-perfused tissue model. Thermometry confirmed the accuracy of the results obtained. The radiothermotherapy system described here was tested in animal experiments, and is presently being used in a clinical pilot study.

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The application of hyperthermia in tumor therapy is expanded to a high degree. As affecting point in biological tissue the following is discussed: Cytotoxic effect with temperatures of 43 degrees C with alterations on cell membrane and in intermediate metabolism, injury of microcirculation, where--because of a pathological vascularisation--tumor tissue is affected in a stronger way than the better adapted vessel net of normal tissue. The radiosensitizing effect between 40 and 42 degrees C is of interest for radiologist. Degree and duration of temperature and the interval between irradiation and thermal application modify the amplifying thermal factor. As adjuvant therapeutic modality the hyperthermia can decrease the hypoxic radioresistant part of cells and is an additional palliative therapeutic measure. Indications within a curative radiotherapy are elaborated at present globally.

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In 232 surgically treated and irradiated patients with breast carcinoma 27 cases of radiogeneous pneumopathia were found and analyzed in the chest radiograph. Special attention was given to the evaluation of the stage and the course of the radiation pneumonitis. No correlation between clinical results and x-ray symptoms was seen. Not every roentgenologically diagnosed pneumonitis is seen in the late follow-up as a fibrosis. The reasons for this are discussed. For the improved detectability of pneumonitic changes in the p.a. or lateral image no significant differences were found and no general rules. Additional CT-investigations of the chest demonstrated the radiogeneous lung changes more clearly and more exactly in its depths. Therefore an exact use of CT in the diagnostics of pneumonitis can be useful, but must be seen under the aspects of relevant therapy the availability of methods and economy.

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A system for thermoradiotherapy of cervical carcinoma is presented, that allows combination of high-dosed afterloading short-time therapy by means of the technique being available in the GDR (DEKATRON) with the equipment CALOTHERM, constructed in Institut M. v. Ardenne. The first clinical experiences (3 patients) show, that the expected target temperature of 42 degrees C at the cervix was reached by all means after 6 minutes at least. Complications involved by hyperthermia did not appear with it, so that the continuation of this therapy is planned in form of a phase-I-study.

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In a pilot study, 8 shoats of the "Edelschwein" breed were submitted to a combined treatment with hyperthermia (5 X 60 min; 42 degrees C in the thoracic region) followed by irradiation of the right lung (5 X 4 Gy). Heating was performed using an applicator of the Selectotherm equipment working at 27 MHz with a power output of 1.5 to 8.0 kW; the irradiation was done with the telecobalt machine Chisobalt. Radiologic checks of the thoracic organs and laboratory diagnostics provided useful data as to the temporal course of the radiogenic pulmonary affections and the tolerability of fractionated whole-body hyperthermia including superimposed local heating on shoats. Histologic examinations of sections of heated and irradiated (right) as compared to exclusively heated (left) lung lobes of 4 animals suggested that hyperthermia exerted a radiosensitizing effect on the right lungs. Histologically confirmed irreversible lung fibrosis occurred there after exposure to even lower total doses following hyperthermia as compared to sole irradiation.

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