International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Oct 2005
Reirradiation of recurrent high-grade gliomas using amino acid PET (SPECT)/CT/MRI image fusion to determine gross tumor volume for stereotactic fractionated radiotherapy.
To develop a valid treatment strategy for recurrent high-grade gliomas using stereotactic hypofractionated reirradiation based on biologic imaging and temozolomide. ⋯ This is the first study of biologic imaging optimized SFRT plus temozolomide in recurrent high-grade gliomas. It demonstrates the feasibility and safety of this approach. The most striking result of the trial is the statistically significant longer survival time in the univariate analysis for patients reirradiated using MET-PET or IMT-SPECT/CT/MRI image fusion in the treatment planning, in comparison to patients treated based on MRI/CT alone. Multivariate analysis confirmed a significant survival benefit from multimodal treatment (i.e., addition of temozolomide), despite the limited number of patients. Whether treatment planning with SPECT/PET independently influences survival has to be studied in a larger series of patients.
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Int. J. Radiat. Oncol. Biol. Phys. · Oct 2005
Acute genitourinary toxicity after high-dose-rate (HDR) brachytherapy combined with hypofractionated external-beam radiation therapy for localized prostate cancer: correlation between the urethral dose in HDR brachytherapy and the severity of acute genitourinary toxicity.
Several investigations have revealed that the alpha/beta ratio for prostate cancer is atypically low, and that hypofractionation or high-dose-rate (HDR) brachytherapy regimens using appropriate radiation doses may be expected to yield tumor control and late sequelae rates that are better or at least as favorable as those achieved with conventional radiation therapy. In this setting, we attempted treating localized prostate cancer patients with HDR brachytherapy combined with hypofractionated external beam radiation therapy (EBRT). The purpose of this study was to evaluate the feasibility of using this approach, with special emphasis on the relationship between the severity of acute genitourinary (GU) toxicity and the urethral dose calculated from the dose-volume histogram (DVH) of HDR brachytherapy. ⋯ It was concluded that HDR brachytherapy combined with hypofractionated EBRT is feasible for localized prostate cancer when considered from the viewpoint of acute toxicity. Increase in the fraction dose or reduction in the number of fractions in HDR brachytherapy did not affect the severity of acute GU toxicity, and the volume of urethra receiving an equal or lower radiation dose than the prescribed dose was more closely associated with the grade severity of acute GU toxicity than that receiving a higher than the prescribed dose.
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Int. J. Radiat. Oncol. Biol. Phys. · Oct 2005
High-dose radiation improved local tumor control and overall survival in patients with inoperable/unresectable non-small-cell lung cancer: long-term results of a radiation dose escalation study.
To determine whether high-dose radiation leads to improved outcomes in patients with non-small-cell lung cancer (NSCLC). ⋯ Higher dose radiation is associated with improved outcomes in patients with NSCLC treated in the range of 63-103 Gy.
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Int. J. Radiat. Oncol. Biol. Phys. · Oct 2005
Rectal wall sparing effect of three different endorectal balloons in 3D conformal and IMRT prostate radiotherapy.
To investigate the dosimetric consequences and rectal wall (Rwall) sparing effect of three different endorectal balloons (ERBs) for three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) for prostate cancer. ⋯ In 3D-CRT, any ERB showed a significant rectal wall sparing effect. ERB2 and ERB3 were superior to ERB1. For both 3D-CRT and IMRT, a reduction of the relative inner Rwall surface exposed to intermediate and high doses was found, which may lead to reduced late rectal toxicity. Development of user- and patient-friendly ERBs is warranted to increase their acceptability.