Strahlentherapie und Onkologie : Organ der Deutschen Röntgengesellschaft ... [et al]
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To investigate the dose distribution in active bone marrow of patients undergoing intensity-modulated radiotherapy (IMRT) for prostate cancer and compare it to the distribution in the same patients, if they had been treated using conformal plans, in order to develop criteria for optimization to minimize the estimated risk of secondary leukemia. ⋯ There are significant differences in the dose-volume histograms of bone marrow doses from 3-D CRT and from IMRT. Pronounced dose inhomogeneity reduces the risk of leukemia compared to homogeneous radiation exposure of the bone marrow. The mean bone marrow dose is therefore not a useful criterion to judge plan quality, since scattered low doses to distant sites may be more critical than the high dose volumes receiving > 10 Gy. The number of monitor units needed to deliver an IMRT plan affects leakage dose and their incorporation into planning constraints should be considered.
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To evaluate the feasibility, safety and efficacy of daily temozolomide concurrent with postoperative radiotherapy in malignant glioma. ⋯ Postoperative radiochemotherapy with 30-33 daily doses of temozolomide (75 mg/m(2)) is safe in patients with malignant glioma. The combined schedule is effective in oligodendroglioma patients and may prolong survival in glioblastoma. Effort should be taken to minimize corticosteroid doses, since both steroids and temozolomide lead to immunosuppression.
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Comparative Study Clinical Trial Controlled Clinical Trial
Automatic generation of a plan optimization volume for tangential field breast cancer radiation therapy.
Dose homogeneity is one of the objectives during computer planning of postoperative radiotherapy of the conserved breast. For three-dimensional (3-D) optimization of the dose distribution using serial CT scan images, suitable volumes have to be delineated. The purpose of this study was to develop a computer-generated delineation of a plan optimization volume (POV) and an irradiated volume (IV) and to automate their use in a fast dose homogeneity optimization engine. ⋯ This automated planning method is capable of replacing the contouring of the clinical target volume as well as the trial-and-error procedure of assigning weights of wedged and unwedged beams by an experienced planner.
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Comparative Study Clinical Trial Controlled Clinical Trial
Evaluation of HDR interstitial breast implants planned by conventional and optimized CT-based dosimetry systems with respect to dose homogeneity and conformality.
Recently, the use of brachytherapy for partial breast irradiation has increased significantly. The aim of this study was to make dosimetric comparisons between conventional (CONV) and CT-based optimized dosimetry systems applied to breast implants. ⋯ With CT-based optimized dose planning the target coverage can be significantly increased compared to the conventional dosimetry systems, but the target dose distribution will be more inhomogeneous. To improve the quality of brachytherapy implants, the image-based three-dimensional information should be used not only for dose plan evaluation, but also previously, for planning the geometry of the catheter positions and performing the insertions.
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Comparative Study Clinical Trial
Multimodality treatment including postoperative radiation and concurrent chemotherapy with weekly docetaxel is feasible and effective in patients with oral and oropharyngeal cancer.
To examine the feasibility and efficacy of weekly docetaxel with concurrent radiation as postoperative treatment in a multimodality approach to oral and oropharyngeal cancer. ⋯ Concurrent radiation and chemotherapy with weekly docetaxel is a feasible postoperative treatment in a multimodality approach to oral and oropharyngeal cancer, resulting in high overall and disease-free survival. This approach warrants further evaluation in prospective randomized trials.