Strahlentherapie und Onkologie : Organ der Deutschen Röntgengesellschaft ... [et al]
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The German Hodgkin Study Group (GHSG), including more than 500 participating centers, established a central radiotherapy (RT) reference center to improve quality of treatment, starting with the first study generation in 1978. More than 11,000 patients with Hodgkin's lymphoma (HL) have been enrolled into these trials. Extensive continuing quality assurance programs (QAPs) during the study generations have been performed. The purpose of the present article is to summarize the experiences and results of the performed and ongoing QAPs. ⋯ Today, radiation oncologists in the GHSG perform a continuous and efficient QAP to improve treatment quality of study patients. For early favorable and unfavorable HL a central prospective review of all diagnostic imaging is performed by expert radiation oncologists to control the disease extension and to define the IF treatment volume. Retrospective analysis of RT portals by an expert panel detects faults in the applied irradiation. Participants are trained on the definition of IF-RT by workshops on the occasion of annual GHSG meetings and on the annual meetings of the German Society of Therapeutic Radiation Oncology (DEGRO). For the advanced stages a multidisciplinary panel evaluates the treatment response to chemotherapy. Patients with a poor response receive additional RT due to the panel's recommendation. The introduction of teleradiotherapy into the GHSG trials improves the dialogue between the central RT reference center and study participants and thus contributes to high RT quality for study patients.
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Comparative Study
Sites of failure in breast cancer patients with extracapsular invasion of axillary lymph node metastases. No need for axillary irradiation?!
Extracapsular spread (ECS) is frequent, but the specific sites of relapse are seldom given in the literature. In this study it was evaluated, if ECS might be an indicator for axillary irradiation. ⋯ ECS was accompanied by an enhanced axillary failure rate in univariate analysis, which was no longer true after adjusting for the number of positive lymph nodes.
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Comparative Study
Measurements of characteristics of time pattern in dose delivery in step-and-shoot IMRT.
Although intensity-modulated radiotherapy (IMRT) has already shown its clinical benefit, there are some issues which are not yet fully understood. Among these is the question whether the protracted dose delivery due to the lowered dose rate has any radiobiological consequences. To investigate this question, an exact characterization of dose rate profiles in typical clinical plans is needed. Furthermore, such a characterization may lead to an increased knowledge how to improve IMRT technically. ⋯ These data show a great inhomogeneity of dose rates not only between different plans but also between different points in the same plan. Biological investigations are needed to quantify the relevance of these inhomogeneities. The parameters which are introduced in this work may be suitable to compare different optimization algorithms in IMRT.
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Comparative Study
Comparative analysis of the effects of belly board and bladder distension in postoperative radiotherapy of rectal cancer patients.
To compare the effect of reducing the irradiated small-bowel volume with the use of belly board, bladder distension or both methods combined, in patients with rectal cancer undergoing postoperative pelvic radiotherapy. ⋯ Bladder distension was a more effective method than the belly board for reducing the irradiated small-bowel volume in postoperative pelvic radiotherapy of rectal cancer patients. The combination of the belly board and bladder distension showed an additive effect and was the most effective method for reducing the irradiated small-bowel volume.