International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Feb 2005
Multicenter StudyImproved biochemical relapse-free survival with increased external radiation doses in patients with localized prostate cancer: the combined experience of nine institutions in patients treated in 1994 and 1995.
To study the radiation dose-response as determined by Kaplan-Meier prostate-specific antigen (PSA) disease-free survival (PSA-DFS) estimates in patients with stage T1-T2 prostate cancer treated within a 2-year period (1994-1995). ⋯ Differences in PSA-DFS estimates observed in multiple retrospective series have been attributed to differences in follow-up duration between patients treated to conventional doses (longer follow-up intervals) and those treated to higher doses (shorter follow-up intervals). In this report, the median follow-up duration in the > or =72 Gy group was essentially identical to the <72 Gy group, because the study included a large number of patients treated consecutively during a narrow time range (1994-1995). With similar follow-up duration, higher than conventional radiotherapy doses were associated with improved PSA-DFS when controlled for the influence of pretreatment PSA levels, biopsy GS, and clinical T stage.
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Int. J. Radiat. Oncol. Biol. Phys. · Feb 2005
Multicenter Study Clinical TrialToxicity and outcome results of RTOG 9311: a phase I-II dose-escalation study using three-dimensional conformal radiotherapy in patients with inoperable non-small-cell lung carcinoma.
To evaluate prospectively the acute and late morbidities from a multiinstitutional three-dimensional radiotherapy dose-escalation study for inoperable non-small-cell lung cancer. ⋯ The radiation dose was safely escalated using three-dimensional conformal techniques to 83.8 Gy for patients with V(20) values of <25% (Group 1) and to 77.4 Gy for patients with V(20) values between 25% and 36% (Group 2), using fraction sizes of 2.15 Gy. The 90.3-Gy dose level was too toxic, resulting in dose-related deaths in 2 patients. Elective nodal failure occurred in <10% of patients.
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Int. J. Radiat. Oncol. Biol. Phys. · Feb 2005
Multicenter Study Comparative StudyFailure definition-dependent differences in outcome following radiation for localized prostate cancer: can one size fit all?
To compare long-term outcome using alternative failure definitions after external beam radiation for localized prostate cancer. ⋯ There are notable differences in both short- and long-term outcomes after definitive radiation for prostate cancer depending on the failure definition applied. Failure definitions must be tested objectively for sensitivity and specificity in predicting clinical outcome, and it is only in this manner that reasonable choices can be made. Although traditional surgical-type failure definitions do not seem applicable to patients treated with external beam radiation, further analysis of definitions across multiple therapeutic modalities is necessary to determine whether a universal failure definition might be feasible, at least for research and comparative purposes.
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Int. J. Radiat. Oncol. Biol. Phys. · Feb 2005
Infrastructure of radiation oncology in France: a large survey of evolution of external beam radiotherapy practice.
To study the structural characteristics of radiation oncology facilities for France and to examine how technological evolutions had to be taken into account in terms of accessibility and costs. This study was initiated by the three health care financing administrations that cover health care costs for the French population. The needs of the population in terms of the geographic distribution of the facilities were also investigated. The endpoint was to make proposals to enable an evolution of the practice of radiotherapy (RT) in France. ⋯ On the basis of the findings of this study, measures were taken to update the infrastructure of RT in France. A first evaluation showed an improvement of care supply in RT in the country.
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Int. J. Radiat. Oncol. Biol. Phys. · Feb 2005
Clinical TrialA dose-escalation trial with the adaptive radiotherapy process as a delivery system in localized prostate cancer: analysis of chronic toxicity.
To evaluate the validity of the chosen adaptive radiotherapy (ART) dose-volume constraints while testing the hypothesis that toxicity would not be greater at higher tumor dose levels. ⋯ By applying the ART process--namely, developing a patient-specific PTV--to prostate cancer patients, significant dose escalation can be achieved without increases in genitourinary or gastrointestinal toxicity. Our data validate the rectal and bladder dose-volume constraints chosen for our three-dimensional conformal and IMRT prostrate radiotherapy planning.