Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology
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Randomized Controlled Trial Multicenter Study Clinical Trial
The influence of the boost technique on local control in breast conserving treatment in the EORTC 'boost versus no boost' randomised trial.
The EORTC Trial 22881/10882 investigating the role of a boost dose in breast conserving therapy demonstrated a significantly better local control rate with the higher radiotherapy dose, especially in women younger than 50 years of age. This paper investigates the potential impact of the different boost techniques on local control and on fibrosis after breast conserving therapy. ⋯ Although the three groups are of a rather unequal size, the results of the interstitial boost seem similar in terms of fibrosis and at least as good in terms of local control, despite a lower treatment volume and a longer overall treatment time.
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Multicenter Study Comparative Study
Comparative study of permanent interstitial prostate brachytherapy post-implant evaluation among seven Italian institutes.
The purposes of this multicentric study are (a) the evaluation of four different commercially available treatment planning systems (TPSs) and (b) to verify whether the dosimetric results are comparable, also when considering the inter-observer variabilities and the different scanning protocols used. This work is to be considered a first step to test the value of multicentric studies based on dosimetric evaluation of the quality of the implants. ⋯ Three-dimensional (3D) geometric reconstructions of seed distributions are slightly dependent upon the operators and the scanning protocols have little effect on the dosimetric evaluation. Some relevant discrepancies were found between one of the TPSs and the other three if few sources were used; increasing the number of seeds those differences became less pronounced. Multicentric studies on the quality of prostate implants based on post-implant dosimetry are feasible, provided an accurate step-wise evaluation of the procedure be performed.
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Multicenter Study
Relationships between DVHs and late rectal bleeding after radiotherapy for prostate cancer: analysis of a large group of patients pooled from three institutions.
Accurate modeling of late rectal reactions needs the collection of individual 3D dose-volume data (i.e. DVH) as well as clinical information of large cohorts of patients. The possibility of collecting a large number of patients with many different dose-volume combinations is very suitable for this purpose. ⋯ Our data confirm the role of the rectal DVH in separating groups of patients having prostate radiotherapy in low and high risk of developing late bleeding. Based on these results, V50 below 60-65% and V60 below 50-55% seem to be the robust cut-off values to keep the risk of developing late rectal bleeding reasonably low. However, due to the 'heterogeneity' of the considered population, the results found should be applied with caution in 'more homogeneous' groups of patients. The association of adjuvant hormone deprivation seems to be associated with an increased risk of rectal toxicity; the mechanism for this effect should be a focus of further research.
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Multicenter Study Clinical Trial
Up-front centralized data review and individualized treatment proposals in a multicenter pediatric Hodgkin's disease trial with 71 participating hospitals: the experience of the German-Austrian pediatric multicenter trial DAL-HD-90.
A systematic procedure for up-front centralized data review and the set-up of individualized treatment proposals was integrated prospectively into the German-Austrian multicenter trial DAL-HD-90 for pediatric Hodgkin's disease (HD) in order to introduce local radiotherapy according to the individual patient's spread of disease within a combined-modality treatment. This paper investigates the feasibility of such a procedure and its impact on the final definition of the extent and stage of disease as well as on the choice of treatment. ⋯ The up-front centralized review of patient data and consecutive set-up and delivery of individualized treatment proposals for almost every patient are feasible within a large multicenter trial. Sufficient time and manpower at the study center are needed for the review process and the set-up of individualized treatment proposals. Such a procedure has a significant impact on the homogeneity of stage definition, allocation to TG, and individualized treatment proposals.
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Multicenter Study Comparative Study
Conformal radiotherapy for lung cancer: different delineation of the gross tumor volume (GTV) by radiologists and radiation oncologists.
Delineation of the gross tumor volume (GTV) and organs at risk constitutes one of the most important phases of conformal radiotherapy (CRT) procedures. In the absence of a clear redefinition of the GTV, for a given pathology, complemented by detailed contouring procedures, the GTV are likely to be estimated rather arbitrarily with the risk of tumor underdosage or detriment to the surrounding healthy tissues. The objective of this study was to compare the delineation of the GTV of intrathoracic tumors by radiologists and radiation oncologists with experience in the field in various centers. ⋯ Major discordances were observed between the radiation oncologists' and the radiologists' delineations, indicating that this step needs to be improved. A better training of radiation oncologists in thoracic imaging and collaboration between radiation oncologists and radiologists should decrease this variability. New imaging techniques (image fusion, positron emission tomography, magnetic resonance imaging spectroscopy, etc.) may also provide a useful contribution to this difficult delineation.