[en] 173 patients were subjected to radiotherapy of prostate carcinomas classified with stages A to C. Five-year survival (uncorrected results) was seen in 100% of the stage A patients (n=6), while the survival rates determined for the stage B and C patients were 79% and 68%, respectively. The results of aspiration biospies permitted 116 patients to be treated by radiation alone, in 30 patients radiation was preceded by surgery and a further 27 subjects additionally received hormones in connection with the primary treatment chosen. The analysis was based on the survival rates, rate of recidivation, time elapsing before the occurrence of metastases and frequency of metastisation, which were in each case correlated to the tumour stage, grade of differentiation and the type of primary treatment used. It was confirmed that tumour stage and grading are of great importance to patient outcome. Broadening of the primary therapeutic measures (to include surgery and/or hormones) offered no perceptible advantages over the sole use radiotherapy. Transurethral resection (TUR) rather appeared to have udesirable effects on the group of patients, in which this invasive method of diagnosis was used. The metastisation rate determined here was three times higher than that of patients subjected to aspiration biopsy. Furthermore, TUR may compromise the subsequent use of radiotherapy, as the traumatic lesions of the tissue are a likely cause of complications. In view of the high frequency of lymphogenic metastases, any curvative treatment carried out in stages B and C ought to include radiation of the regional lymph nodes. In patients showing micrometastisation, the adequacy of the 40 Gy dose used here must be carefully examined. Evaluations of patients surviving for equal periods of time have shown that radical prostectomy, as compared to successful radiotherapy, tends to be connected with a greater number of usually more dramatic side-effects. (orig./HG)

No abstract available

No abstract available

[en] The effects of tissue damage associated with invasive pO₂ measurements on radiation sensitivity were investigated using a xenografted squamous cell carcinoma model. For the tumour cure experiments, single dose irradiations were given following different regimens of polarographic pO₂ measurements associated with different degrees of mechanical tissue damage. With a dose of 32 Gy, 57% of animals were cured. Following 3 tracks of needle measurements, 73% of tumours were locally controlled, and 75% were cured after 8 needle tracks. The polarographic measurements gave virtually identical oxygenation data for recurrent or cured tumours (both median pO₂ 1.0 mmHg), respectively. There was thus no evidence of decreased radiosensitivity associated with tissue damage after invasive pO₂ measurements. The pre-therapeutic oxygenation status gave no evidence for a prediction of radiation response on an individual basis. (orig.)

[en] In this retrospective study the records of 157 patients with the diagnosis of multiple myeloma were evaluated with regard to subjective pain relief after a series of radiation therapy at 389 local sites. The most frequently treated region was the spine (50.2%), followed by the thoracic wall (17.9%) and the upper and lower extremities (17.8%). The median survival after diagnosis of all patients was 36 months. 88.4% of all treated sites showed good to moderate response in terms of pain remission after irradiation. It is shown that pain relief is significantly dependent on the total dose but independent of the dose per fraction. A total dose of 30 Gy in two weeks (5x3 Gy/week) is recommended as a well tolerated and reasonable treatment option to achieve maximum palliation and minimum hospitalization time for patients in whom multiple myeloma is diagnosed. (orig.)

[en] The effect of fractionated irradiation on the oxygenation status of experimental tumours was investigated using polarographic assessment of the pO₂ distribution. Since an improvement in tumour oxygenation could simply be the result of tumour shrinkage, a comparison of pO₂ readings of untreated size-matched control tumours was performed. Irradiation was carried out using 6 fractions of 6 Gy applied within 11 days. A comparison of polarographic pO₂ data with size-matched untreated tumours revealed a significant improvement in oxygenation after the irradiation. The median pO₂ was 0.9±0.1 mmHg for unirradiated tumours at a volume of 180 mm³, while the corresponding data for irradiated tumours of comparable size were 2.3±0.5 mmHg on day 21 and 4.8±0.9 mmHg on day 28 after start of irradiation. From these results it can be concluded that the improvement of oxygenation after fractionated irradiation is not solely the result of a reduced tumour volume. (orig.)

No abstract available

[en] Predictive assays would be very useful in order to determine individual radiosensitivity and to individualize cancer therapy. We have determined after irradiation cytogenetic damage by expression of micronuclei, DNA repair kinetics by comet assay and cell proliferation by flow cytometry. The comet assay seems to be very useful in order to recognize radiosensitive patients in whom severe radiation damage will occur. The micronucleus assay gives variable results but the determination of cell proliferation plus micronuclei has a good potential to predict radiation response in tumours. Determination of quiescent S-phase cells gives information about the degree of hypoxia in tumours. (orig.)

[en] Background: Pronounced oxygen deficiency in tumors which might be caused by a diminished oxygen transport capacity of the blood (e.g., in anemia) reduces the efficacy of ionizing radiation. The aim of this study was to analyze whether anemia prevention by recombinant human erythropoietin (rHuEPO) affects the radiosensitivity of human glioblastoma xenografts during fractionated irradiation. Material and Methods: Anemia was induced by total body irradiation (TBI, 2 x 4 Gy) of mice prior to tumor implantation into the subcutis of the hind leg. In one experimental group, the development of anemia was prevented by rHuEPO (750 U/kg s.c.) given three times weekly starting 10 days prior to TBI. 13 days after tumor implantation (tumor volume approx. 40 mm³), fractionated irradiation (4 x 7 Gy, one daily fraction) of the glioblastomas was performed resulting in a growth delay with subsequent regrowth of the tumors. Results: Compared to nonanemic control animals (hemoglobin concentration cHb = 14.7 g/dl), the growth delay in anemic mice (cHb = 9.9 g/dl) was significantly shorter (49 ± 5 days vs. 79 ± 4 days to reach four times the initial tumor volume) upon fractionated radiation. The prevention of anemia by rHuEPO treatment (cHb = 13.3 g/dl) resulted in a significantly prolonged growth delay (61 ± 5 days) compared to the anemia group, even though the growth inhibition found in control animals was not completely achieved. Conclusions: These data indicate that moderate anemia significantly reduces the efficacy of radiotherapy. Prevention of anemia with rHuEPO partially restores the radiosensitivity of xenografted glioblastomas to fractionated irradiation. (orig.)

[en] The present study investigated the effect of fractionated low dose-rate (FLDR) treatments in mouse lip mucosa, a typically early reacting tissue. The relation between dose-rate and fractionation effect has been assessed with various interfraction intervals and dose-rates. A fixed overall treatment time of 10 h has been used for the present continuous and fractionated irradiation experiments with corresponding dose-rates of 3.1-84 Gy/h. Sophisticated mathematical models are now available to estimate repair parameters from data derived with different fraction numbers, fraction sizes and dose-rates. These formulas, allowing the calculations of isoeffect relationships are based on the incomplete repair model and assume that repair can operationally be described by a monoexponential function. A further assumption of these models is that repair of sublethal damage follows the same kinetics during irradiation and between fractions. The present FLDR experiments with small inter-fraction spacing were performed to investigate the validity of these assumptions and consequently the applicability of the models. In addition, it has been assessed whether the experimental approach of investigating repair kinetics as such [high dose-rate split-course vs. continuous low dose-rate or FLDR] influences the estimation of these parameters, as has been suggested from the analysis of in vitro studies. Using the mucosal desquamation endpoint, virtually identical repair parameters have however been estimated with different approaches (α/β=14.1-18.2 Gy, T_1/2=28-37 min). The available iso-effect models seem to be applicable to the present experimental data and might after further experimental tests also involving late reacting tissues, be a useful tool for clinical isoeffect calculations. (author)> 26 refs.; 2 figs.; 3 tabs