International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2004
Dosimetric correlates for acute esophagitis in patients treated with radiotherapy for lung carcinoma.
Acute esophagitis is a common complication of radiotherapy (RT) for non-small-cell carcinoma of the lung. Previous reports have related esophagitis to dosimetric parameters such as the length of the irradiated esophagus, maximal dose, or volume of the organ treated beyond a threshold dose. However, when using oblique beams, a portion of the esophageal circumference may be outside the treated field, resulting in partial esophageal irradiation. Therefore, our aim was to determine whether the irradiated esophageal surface area and/or esophageal volume are predictive of acute esophagitis in relation to other clinical and treatment-related factors. ⋯ The esophageal surface area receiving > or =55 Gy, the esophageal volume receiving > or =60 Gy, and the use of concurrent chemotherapy were the most statistically significant predictive factors for early esophagitis. Adequate dosimetric coverage of the planning target volume remains the goal of RT planning. High values of A(55) and/or V(60) are indicative of the development of acute esophagitis and may indicate a need to explore alternative RT planning options.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2004
Evaluation of the influence of breathing on the movement and modeling of lung tumors.
Respiration causes movement and potential shape change in lung tumors that are not fully appreciated using conventional free-breathing CT models for radiotherapy planning. Although target expansion has the potential to ensure proper tumor coverage in the face of motion on a free-breathing CT scan, large variations in how individual patients' tumors move may make such expansions difficult to uniformly define. In addition, excessive expansion may result in the unnecessary inclusion of normal lung in the treated volume. This study was designed to evaluate the influence of breathing movement on tumors and to assess the validity of the free-breathing CT scan for target delineation in the lung. ⋯ Traditional methods of expanding the GTV to CTV by 1 cm are less than ideal. This method tends to include more normal lung than necessary and may lead to marginal miss. Interpatient tumor movement variations further prohibit defining a simple rule for nonuniform expansion that would minimize the volume of normal lung in the target. Although the development of target volumes by combining information from breath-hold CT scans at inhale and exhale states shows some promise in minimizing excess lung irradiated while maintaining adequate tumor coverage, further tests of breathing reproducibility need to be performed to provide a confident baseline for defining target expansions by this technique.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2004
Randomized Controlled Trial Multicenter Study Clinical TrialA multinational, randomized phase III trial of iseganan HCl oral solution for reducing the severity of oral mucositis in patients receiving radiotherapy for head-and-neck malignancy.
Oral mucositis (OM) causes significant morbidity during the course of radiotherapy (RT) treatment of head-and-neck cancer. It is hypothesized that infection plays a role in the development of OM. We tested the efficacy of iseganan HCl (iseganan), a synthetic peptide with broad-spectrum antimicrobial activity, for preventing RT-associated OM. ⋯ Iseganan oral solution was safe but did not reduce the risk for developing ulcerative OM relative to placebo. Intensified oral hygiene or the administration of the vehicle used to deliver study drug in this trial appears to have reduced the risk and severity of OM. Our results suggest that antimicrobial intervention may not meaningfully affect the pathogenesis of radiation-induced OM.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2004
Initiation of a teleradiotherapeutic network for patients in German lymphoma studies.
Deviations of radiation treatment portals and dose from prospective treatment plans are unfavorable prognostic factors for lymphoma patients. Therefore, an extensive radiotherapy quality assurance program is used in the ongoing German lymphoma studies. The introduction of teleradiotherapy offered the opportunity to optimize and simplify the workflow of these quality assurance programs. The purpose of this report was to evaluate the feasibility of teleradiotherapy and to describe our experiences with these innovative tools. ⋯ The introduction of teleradiotherapy improved the dialog between the radiotherapy reference centers and study centers and thus contributed toward high radiotherapy quality for lymphoma patients in Germany.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2004
Case Reports Comparative StudyAdvantage of protons compared to conventional X-ray or IMRT in the treatment of a pediatric patient with medulloblastoma.
To compare treatment plans from standard photon therapy to intensity modulated X-rays (IMRT) and protons for craniospinal axis irradiation and posterior fossa boost in a patient with medulloblastoma. ⋯ The present study clearly demonstrates the advantage of conformal radiation methods for the treatment of posterior fossa and spinal column in children with medulloblastoma, when compared to conventional X-rays. Of the two conformal treatment methods evaluated, protons were found to be superior to IMRT.