Strahlentherapie und Onkologie : Organ der Deutschen Röntgengesellschaft ... [et al]
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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.
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Review Comparative Study
Positron emission tomography for radiation treatment planning.
To evaluate the impact of positron emission tomography (PET) on target volume delineation for radiation treatment planning. ⋯ Regarding treatment planning in radiotherapy, PET offers advantages in terms of tumor delineation and the description of biological processes. To define the real impact of this investigation in radiation treatment planning, subsequent experimental, clinical and cost-benefit analyses are required.
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Radiation treatment of head-and-neck tumors mostly leads to a damage to the salivary glands and a consequential permanent loss of saliva. The aim of this investigation was to establish a modern three-dimensional conformal radiotherapy (3D-CRT) to show a decrease in severe xerostomia in contrast to the proven conventional technique (K-RT) with photons and electrons. ⋯ Basically, 3D-CRT seems to be suitable as a standard for all patients with carcinomas of the oral cavity, oro- and hypopharynx. Especially in patients with tumors located in the larynx and hypopharynx, averaged D(mean) doses of both parotids during irradiation can be reached, to conserve salivary flow rates, which are similar to baseline flow rates.