International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2014
Effect of cerebellum radiation dosimetry on cognitive outcomes in children with infratentorial ependymoma.
Cognitive decline is a recognized effect of radiation therapy (RT) in children treated for brain tumors. The importance of the cerebellum and its contribution to cognition have been recognized; however, the effect of RT on cerebellum-linked neurocognitive deficits has yet to be explored. ⋯ Sparing portions of the cerebellum should be considered in RT planning for children with infratentorial ependymoma because of the potential impact of radiation dose on cognitive function.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2014
Randomized Controlled TrialSecondary analysis of RTOG 9508, a phase 3 randomized trial of whole-brain radiation therapy versus WBRT plus stereotactic radiosurgery in patients with 1-3 brain metastases; poststratified by the graded prognostic assessment (GPA).
Radiation Therapy Oncology Group (RTOG) 9508 showed a survival advantage for patients with 1 but not 2 or 3 brain metastasis (BM) treated with whole-brain radiation therapy (WBRT) and stereotactic radiosurgery (SRS) versus WBRT alone. An improved prognostic index, the graded prognostic assessment (GPA) has been developed. Our hypothesis was that if the data from RTOG 9508 were poststratified by the GPA, the conclusions may vary. ⋯ This secondary analysis of predominantly lung cancer patients, consistent with the original analysis, shows no survival advantage for the group overall when treated with WBRT and SRS; however, in patients with high GPA (3.5-4), there is a survival advantage regardless of whether they have 1, 2, or 3 BM. This benefit did not extend to patients with lower GPA. Prospective validation of this survival benefit for patients with multiple BM and high GPA when treated with WBRT and SRS is warranted.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2014
Functional data analysis in NTCP modeling: a new method to explore the radiation dose-volume effects.
To describe a novel method to explore radiation dose-volume effects. Functional data analysis is used to investigate the information contained in differential dose-volume histograms. The method is applied to the normal tissue complication probability modeling of rectal bleeding (RB) for patients irradiated in the prostatic bed by 3-dimensional conformal radiation therapy. ⋯ Functional data analysis provides an attractive method for flexibly estimating the dose-volume effect for normal tissues in external radiation therapy.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2014
Comparative StudyIntensity modulated proton therapy for craniospinal irradiation: organ-at-risk exposure and a low-gradient junctioning technique.
To compare field junction robustness and sparing of organs at risk (OARs) during craniospinal irradiation (CSI) using intensity modulated proton therapy (IMPT) to conventional passively scattered proton therapy (PSPT). ⋯ IMPT has the potential to improve CSI plan quality and the homogeneity of intrafractional dose at match lines. The IMPT approach developed may also simplify treatments and reduce workload per patient relative to PSPT.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2014
Partial breast radiation therapy with proton beam: 5-year results with cosmetic outcomes.
We updated our previous report of a phase 2 trial using proton beam radiation therapy to deliver partial breast irradiation (PBI) in patients with early stage breast cancer. ⋯ Proton beam radiation therapy for PBI produced excellent ipsilateral breast recurrence-free survival with minimal toxicity. The treatment proved to be adaptable to all breast sizes and lumpectomy cavity configurations. Cosmetic results appear to be excellent and unchanged from baseline out to 5 years following treatment. Cosmetic results may be improved over those reported with photon-based techniques due to reduced breast tissue exposure with proton beam, skin-sparing techniques, and the dose fractionation schedule used in this trial.