International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2010
Effect of hyperoxygenation on tissue pO2 and its effect on radiotherapeutic efficacy of orthotopic F98 gliomas.
Lack of methods for repeated assessment of tumor pO(2) limits the ability to test and optimize hypoxia-modifying procedures being developed for clinical applications. We report repeated measurements of orthotopic F98 tumor pO(2) and relate this to the effect of carbogen inhalation on tumor growth when combined with hypofractionated radiotherapy. ⋯ The results provide quantitative measurements of the effect of carbogen inhalation on intracerebral tumor pO(2) and its effect on therapeutic outcome. Such direct repeated pO(2) measurements by EPR oximetry can provide temporal information that could be used to improve therapeutic outcome by scheduling doses at times of improved tumor oxygenation. EPR oximetry is currently being tested for clinical applications.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2010
Comparative StudyA more efficient, radiation-free alternative to systematic chest x-ray for the detection of embolized seeds to the lung.
To evaluate the efficacy of a seed-migration detector and to compare its performance to fluoroscopy and postoperative chest radiographs. ⋯ The usual recommendation to perform chest radiographs at the first follow-up visit to scan lungs for embolized seeds should be revised because of the high false-negative rate. Scintillator-based gamma counter detector provides superior detection sensitivity and should be adopted as a standard of practice. Chest X-ray could be limited to documenting cases of positive migration.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2010
Comparative StudyComparison of standardized uptake value-based positron emission tomography and computed tomography target volumes in esophageal cancer patients undergoing radiotherapy.
To study various standardized uptake value (SUV)-based approaches to ascertain the best strategy for delineating metabolic tumor volumes (MTV). ⋯ Regardless of the SUV thresholding method used (i.e., absolute or relative to liver mean), a threshold of approximately 2.5 yields the highest conformality index and best approximates the CT-based GTV at the epicenter. These findings may ultimately aid radiation oncologists in the delineation of the entire GTV in esophageal cancer patients.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2010
Determining which patients require irradiation of the supraclavicular nodal area after surgery for N1 breast cancer.
We designed this study to determine which patients have a high risk of supraclavicular node recurrence in N1 breast cancer previously treated with surgery but not having received supraclavicular radiation therapy (SCRT) and to identify which patients needed SCRT. ⋯ The prognostic factors associated with supraclavicular node recurrence were lymphovascular invasion, extracapsular extension, and the number and level of involved axillary nodes. Patients with two or more prognostic factors might benefit from SCRT.
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Int. J. Radiat. Oncol. Biol. Phys. · Nov 2010
Comparative StudyBreast patient setup error assessment: comparison of electronic portal image devices and cone-beam computed tomography matching results.
To quantify the differences in setup errors measured with the cone-beam computed tomography (CBCT) and electronic portal image devices (EPID) in breast cancer patients. ⋯ EPID registration underestimated the actual bony anatomy setup error in breast cancer patients by 20% to 50%. Using CBCT decreased setup uncertainties significantly.