No abstract available

[en] Complemental radiotherapy during surgery for ensuring radical removal of multi-invasive and multicentric tumors is an acknowledged principle. Irradiation under the operation permits pin-pointed application of a high, single radiation dose to a sharply defined target area, while movable radiosensitive organs can be optimally protected. The requirements of this treatment call for close interdisciplinary collaboration of surgeons and radiooncologists. Due to the demand for highly experienced personnel and sophisticated technology, application of this type of radiotherapy is restricted so far to a few medical centers. The value of the treatment was analysed and proven by an international multi-center study performed by experienced hospitals. The CD-ROM in hand presents a topical survey of ongoing activities, techniques and developments relating to radiotherapy during surgery at the national and international level and is intended to serve as a source of information and further learning for colleagues wishing to specialize in this field. (orig./CB)

[en] Purpose / Objective: Clinical data supporting the relationship between clonogen number, tumor volume and local control is sparse. The aim of this study was to analyse the influence of dose and tumorvolume on the local tumor control probability in nasopharyngeal cancer. Materials and Methods: Between 1982 and Dec. 1993 we have treated 81 patients with nasopharyngeal cancer; 21 lymphoepithelioma, 54 squamous cell carcinoma and 6 undifferentiated carcinomas with a mean dose to the nasopharynx of 62 Gy (range 38 Gy - 74 Gy). Since 1990 we have been using a 3 dimensional treatment planning to boost the primary tumor site. The boost is applied via three non-coplanar irregularly shaped fields which allows us to spare adjacent radiosensitive structures as the optic chiasm and the temporal lobes of the brain. The initial volume of the tumor (1 ccm to 110 ccm) in the nasopharynx was determined from serial slices of pre-treatment CT and/or MRI scans. Results: The median follow-up is now 4.7 years with a minimum of 2 years. There has been no high grade toxicity (WHO III deg. , IV deg. ) during this time. Twenty one patients had a local recurrence and one patient had a recurrence at the margin of the boost-field. At five years the local recurrence free survival was 72% and the overall survival was 59%. Nine patients experienced a nodal failure. Eight patients developed distant metastases. We have found that in a multivariate analysis that the local tumor control depended on the tumor volume and dose to the tumor. This could be quantified by a discriminant analysis. A line of steepness (3.1 ± 0.4) Gy per volume doubling interval was found to separate the group of local recurrent tumors from the group of locally controlled tumors with p= 0.01. This volume effect was analysed for tumor control probability with dose intervals of 3 Gy. We have found that these data could be fitted by a probit function with p=0.007. A TCD50 of (58±3 Gy) for a tumor of 50 ccm. The dose-response relationship was significantly steeper (1.8 ± 0.2%/Gy) after the correction for different tumor volumes than without this correction (1.1%/Gy). Conclusion: It is a common knowledge that larger tumors require higher doses for local control. We have been able to quantitate this effect in nasopharyngeal cancer by precise CT based volumetric measurements to 3.1 Gy per volume doubling. The correction for this effect led a to steeper dose-response relationship, indicating that initial treatment volume is an important prognostic factor. This supports the clinical importance of tumor volume measurements. We feel that these quantification of the dose-volume response may help to individualize the dose prescription. 3D conformal techniques will help to apply higher doses in a safe manner

[en] Radiation therapy of the localized prostatic carcinoma under high-voltage conditions represents a curative treatment technique. The results of the treatment are similar to those of radical surgery, secondary effects altogether being less important. In the case of lymphogeneous metastasition, also a hematogeneous spread has to be supposed; systemic therapy, therefore, is indicated. Optimization of the percutaneous irradiation technique may reduce the side effects to the bladder and intestine, and possibly improves local curability. New aspects of the treatment of certain tumors may be perhaps expected from interstitial therapy. (orig.)

No abstract available

[en] Combined treatment in tumour therapy is aimed at improving the therapeutic results. The article discusses the simultaneous use of chemotherapy and radiotherapy as well as the problems of partial synchronisation of tumour cell collectives before irradiation. After describing theoretical fundamentals and experimental investigations, the clinical findings available so far are discussed. At present, the application of experimental findings to clinical practice still seems problematic. But there are first signs indicating how a synchronisation effect may be utilized in chemotherapy. (orig./AK)

[en] Radiotherapy of malignant lymphomas has yielded excellent results especially in Hodgkin's lymphomas. A high rate of freedom from recurrences combined with a low rate of side effects can be achieved only with optimal radiotherapy. Benefit/risk analyses shows that the side effects are in a favourable proportion to the results achieved. (orig.)

[en] The value of radiotherapy in infantile lymphogranulomatosis is analyzed by a comparison of radiation doses and therapeutic success, and side effects and late radiation effects are described. (AJ)

[en] Radiation-induced pulmonary changes after post-operative high voltage therapy of the carcinoma of the breat is usually greater than following orthovoltage treatment. Among 635 patients treated post- operatively with telecobalt including the chestwall, pneumonitis occurred in 35%. Literature data and the author's own results indicate the need of refined techniques of irradiation and individual planning. (orig.)

[en] The paper studies early detection and radiotherapy, either as pure radiotherapy or as surgical treatment combined with irradiation of tumours of the mouth. Time-dependence, mode of irradiation, tumour stage etc. play an important role. These parameters must be coordinated accurately and specifically in irradiation planning and tumour therapy. It is very important to control possible radiation side-effects. Special regard should be paid to the immunological system. (GSE)