[Influence of radiotherapy on lymphocyte stimulation]. / Zur Beeinflussung der Lymphozytenstimulation durch Strahlentherapie

More than 300 lymphocyte cultures of 12 patients with seminomas were examined during the prophylactic radiotherapy and, in several cases, during an extended period until 20.5 months after the end of the treatment. The object of this study was to find out by measuring the capacity of the lymphocytes to be stimulated in vitro wheather they could be damaged by the radiotherapy. Among other reasons, the above mentioned patients were chosen because they had been submitted to irradiations of vast volumes of lymphatic tissues at a uniform focal dose of 4000 rad. The different opinions expressed in the literature (stimulation decreassed resp. increased resp. unchanged) are reflected by our results in such a way that we did not find a qualitative loss of the capacity to be stimulated cultures. The problem of the different opinions about the capacity of lymphocytes to be stimulated after a radiotherapy appears; among other things, to be based on different examination methods. According to these methods- morphological determination of the relative number of lymphoblasts, synthesis of DNA by fluid scintillation counting, or determination of the number of surviving cells in vitro -different results are obtained. It seems not possible to use the lymphocyte stimulation in vitro as a method of testing clinical sideefects occuring during the characteristics of immunity and radiation biology are not differentiated in a more precise manner.

[Preliminary results with digital luminescence radiography in radiotherapy]. / Erste Erfahrungen mit der digitalen Lumineszenzradiographie (DLR) in der Strahlentherapie.

Port films in radiation therapy suffer from low image contrast und exposure errors. We examined the potential of computed radiography with a storage phosphor system (FCR-901/Siemens Digiscan) to overcome these drawbacks. Port films of various treatment sites were obtained for both, conventional films and digital storage phosphor screens with a DuPont cassette and steel intensifier screens under identical exposure settings. We examined port films from a linear accelerator and from a 60Co source. We found a superior contrast in the digital images and an almost total elimination of exposure errors. The differences between digital and conventional images, however, were less pronounced with films from the 60Co source. Unsharp mask filtering (medium kernel size, moderate enhancement) further improved image quality. Several sources of artefacts in the digital images could be described.

[Preoperative irradiation, cisplatin sensitization and radical surgery of primarily operable carcinomas of the oral cavity. Results of a prospective DOSAK treatment study]. / Pröperative Radiatio, Cisplatin-Sensibilisierung und radikale Resektion primär operabler Mundhöhlenkarzinome. Ergebnisse einer prospektiven Therapiestudie des DOSAK.

165 patients with carcinomas of the oral cavity or oropharynx, clinically appearing operable, were treated between 1985 and 1987 within the framework of a prospective multicenter study. The treatment concept consisted in preoperative irradiation with 32 Gy, cisplatin sensitization with 5 X 20 mg per m2 body surface area and subsequent radical removal of the primary tumor and the regional cervical lymph nodes. Regarding recurrence and survival rates the patient data were analyzed using one- and multi-dimensional statistical methods. The observed survival rates were compared with those assessed with the aid of the treatment-dependent prognosis index TPI (Platz et al. 1982). After 1 years the survival rates under the selected combination therapy were 12% and after 2 years 19% above the assessed survival rates under radical surgery alone.

[Preoperative radio-chemotherapy and radical surgery for advanced carcinomas of the oral cavity. 4-year results of a prospective therapy study with DOSAK]. / Präoperative Radio-Chemotherapie und radikale Operation fortgeschrittener Mundhöhlenkarzinome. 4Jahresergebnisse einer prospektiven Therapiestudie des DOSAK.

Based on the postoperative data evaluated in September 1989, the results of a regional prospective treatment study conducted by the DOSAK on preoperative radio-chemotherapy and radical surgery for carcinomas of the oral cavity and the oropharynx are presented. In the univariate analysis the histologic lymph node findings after pretreatment, the histologic grading, and the TPI correlated well with the survival rates. The multivariate analysis confirmed that the histologic demonstration of vital tumor cells in the neck lymph nodes after the end of pretreatment is of grat prognostic relevance. The histologic degree of differentiation, the demonstration of vital tumor cells in the primary tumor area after pretreatment and the length of time between radiotherapy and surgery were of secondary importance.