Strahlentherapie最新文献

One hundred breast cancer patients were given questionnaires to be completed at home or at the outpatient department. The purpose was to have patients' opinions of the current follow-up system. The response rate was high (93%), which indicates the patients' wish to participate in the decision-making of their treatment. The Department of Radiotherapy and Oncology was the place of choice for follow-up (95%), which is strongly against the trend to transfer follow-up to health centers. Mostly the patients criticized the lack of psychological support. Medical training should focus more on the significance of doctor-patient relationship and mental factors. These points are particularly important for the oncologists because of the special character of cancer and related psychological stress. It is not, however, possible to create a better contact without increasing the time available for each patient, which means more vacancies of oncologists.

A report is given on dose measurements performed in the radiation field close to Ir-192 sources. The dose was measured at a distance of 2 to 8 cm in the air and in a phantom with ionization chambers. Radiachromic foils were used in order to determine the dose distribution surrounding the sources immediately. The measurement results were compared to model calculations and show a good conformity.

In a randomized prospective clinical study, the authors investigate the results of percutaneous radiotherapy (telecobalt) with two rhythms of fractionation in patients with vesical carcinomas. A one-series irradiation with 1.5 Gy daily (except the weekends) up to a total dose of 60 Gy is compared to a two-series irradiation (in the first series 3 Gy three days per week up to 30 Gy, then irradiation-free interval of four weeks, in the second series 1.5 Gy daily up to a total focal dose of 60 Gy). The five-year survival rates are 52% after one-series irradiation and 39% after two-series irradiation. The surgical treatment consisted in a most radical resection of the vesical tumor by TUTUR, partial resection of the wall, of transvesical tumor resection.

Time and dose dependent changes in blood flow and red blood cell volume were studied in the locally irradiated bone marrow of the rat femur after single and fractionated doses of X-rays. With the single dose of 10 Gy the bone marrow blood flow although initially reduced returned to the control levels by seven months after irradiation. With doses greater than or equal to 15 Gy the blood flow was still significantly reduced at seven months. The total dose levels predicted by the nominal standard dose equation for treatments in three, six or nine fractions produced approximately the same degree of reduction in the bone marrow blood flow seven months after the irradiation. However, the fall in the red blood cell volume was from 23 to 37% greater in the three fractions groups compared with that in the nine fractions groups. Using the red blood cell volume as a parameter the nominal standard dose formula underestimated the severity of radiation damage in rat bone marrow at seven months for irradiation with small numbers of large dose fractions.

The somatic dose index was determined for large-field irradiations with the 10 MeV bremsstrahlung of a linear accelerator. Among the possible field shapes, the authors investigated the mantle field, the inverted Y field, the boomerang field, as well as total body irradiation and upper and lower partial body irradiation. The measured data are discussed with respect to clinical aspects.

Disorders of the skeleton in the thoracic area after percutaneous irradiation of malignant lymphomas are relatively rare. The most common site for pathologic changes is the clavicula. Local overdosage and, in case of malignant alterations, an additional chemotherapy might be the reasons. Among our patients seven lesions occurred, three of them were malignant: two osteogenic sarcomas and one chondrosarcoma.

A more extensive interpretation of quality control in radio-oncology is opposed to the conception mostly restricted to technical inspections. A review is given of the most important medical and physical aspects of an optimized radiotherapy. Some examples are chosen from the great number of national and international recommendations agreed upon in order to standardize the measures of quality control. Finally some simple radiobiologic models are presented and the corresponding precision requirements are compared with the uncertainties of the dose determination resulting in clinical practice.

Two rather young patients with spontaneous massive mandible osteolysis are presented, i.e. a woman suffering from a rhinogenous liquor fistula and recurrent meningitides, and a young man. The authors discuss etiology, pathologic anatomy, clinical and radiological course, as well as the combined surgical and radiotherapeutical treatment. The pathologic process shall be stopped by the combination of both therapy methods. A radiation dose of 30 to 50 Gy is recommended.

CT examinations before and after radiotherapy were performed in 48 patients with choroidal melanomas who were submitted for a bulb-preserving irradiation with ruthenium-106. The authors wanted to investigate to which extent further, especially pretherapeutic informations are obtained by computed tomography, if performed in addition to well-known ophthalmologic examinations (ophthalmoscopy, fluorescence angiography, sonography). Furthermore the side reactions of therapy induced by the intervention or by the tumor should be visualized. The measurements of the tumor prominence were of special importance for the therapy planning, because they allowed to verify the response of radiotherapy by computed tomography. Our own patients had an average tumor regression of 1 to 2 mm within the first three months after the irradiation with ruthenium-106; after six months the prominence of the melanomas had decreased by 3 to 4 mm on an average. Interesting side effects, also for the ophthalmologist, were acute radiogenic retino-uveitises and parabulbar oedemas found in several patients who showed a marked regression within one or two weeks. Some late effects were scleral scars at the point of fixation of the ruthenium calotte.

The production of shielding blocks nearly free from air inclusions (pipes), as they are necessary for example in case of mantle field irradiations, is often not possible in a satisfactory manner by means of conventional techniques; furthermore it is time-consuming. The authors present a new method for a fast production of shielding blocks without pipes for radiotherapy.