International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2010
Cardiac mortality in patients with stage I and II diffuse large B-cell lymphoma treated with and without radiation: a surveillance, epidemiology, and end-results analysis.
Standard therapy for stage I and II diffuse large B-cell lymphoma consists of combined modality therapy with anthracycline-based chemotherapy, anti-CD20 antibody, and radiation therapy (RT). Curative approaches without RT typically utilize more intensive and/or protracted chemotherapy schedules. Anthracycline-based chemotherapy regimens are associated with a dose-dependent risk of left ventricular systolic dysfunction. We hypothesize that patients treated without RT, i.e., those who are treated with greater total chemotherapy cycles and hence cumulative anthracycline exposure, are at increased risk of cardiac mortality. ⋯ Increased anthracycline exposure in patients treated only with chemotherapy regimens may result in an increase in cardiac deaths, detectable only through analysis of large sample sizes. Confirmatory evaluation through meta-analysis of randomized data and design of large prospective trials is warranted.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2010
Comparative StudyImpact of fraction size on lung radiation toxicity: hypofractionation may be beneficial in dose escalation of radiotherapy for lung cancers.
To assess how fraction size impacts lung radiation toxicity and therapeutic ratio in treatment of lung cancers. ⋯ This computational study demonstrated that hypofractionated stereotactic body radiotherapy is a better regimen than conventional fractionation in lung cancer patients with small tumors and high doses, because it generates lower RDV when the tumor NTD is kept unchanged.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2010
Review Meta AnalysisRadiation dose-volume effects in the spinal cord.
Dose-volume data for myelopathy in humans treated with radiotherapy (RT) to the spine is reviewed, along with pertinent preclinical data. Using conventional fractionation of 1.8-2 Gy/fraction to the full-thickness cord, the estimated risk of myelopathy is <1% and <10% at 54 Gy and 61 Gy, respectively, with a calculated strong dependence on dose/fraction (alpha/beta = 0.87 Gy.) Reirradiation data in animals and humans suggest partial repair of RT-induced subclinical damage becoming evident about 6 months post-RT and increasing over the next 2 years. Reports of myelopathy from stereotactic radiosurgery to spinal lesions appear rare (<1%) when the maximum spinal cord dose is limited to the equivalent of 13 Gy in a single fraction or 20 Gy in three fractions. However, long-term data are insufficient to calculate a dose-volume relationship for myelopathy when the partial cord is treated with a hypofractionated regimen.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2010
A pilot trial of serial 18F-fluorodeoxyglucose positron emission tomography in patients with medically inoperable stage I non-small-cell lung cancer treated with hypofractionated stereotactic body radiotherapy.
Routine assessment was made of tumor metabolic activity as measured by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in Stage I non-small-cell lung cancer (NSCLC). This report describes PET correlates prospectively collected after stereotactic body radiotherapy (SBRT) for patients with medically inoperable NSCLC. ⋯ A substantial proportion of patients may have moderately elevated FDG-PET SUV(max) at 12 months without evidence of local failure on further follow-up. Thus, slightly elevated PET SUV(max) should not be considered a surrogate for local treatment failure. Our data do not support routine serial FDG-PET/computed tomography for follow-up of patients receiving SBRT for Stage I NSCLC.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2010
Comparative StudyRadiotherapy treatment plans with RapidArc for prostate cancer involving seminal vesicles and lymph nodes.
Dosimetric results and treatment delivery efficiency of RapidArc plans to those of conventional intensity-modulated radiotherapy (IMRT) plans were compared using the Eclipse treatment planning system for high-risk prostate cancer. ⋯ For PTVs including prostate, seminal vesicles, and lymph nodes, IMRT performed better in dose sparing for bladder, rectum, and small bowel than did RapidArc. For PTVs including prostate and seminal vesicles, RapidArc with two arcs provided plans comparable to those for IMRT. The treatment delivery is more efficient with RapidArc.