International journal of radiation oncology, biology, physics
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2012
Comparative StudyBiological optimization in volumetric modulated arc radiotherapy for prostate carcinoma.
To investigate the potential benefits achievable with biological optimization for modulated volumetric arc (VMAT) treatments of prostate carcinoma. ⋯ Biological optimization can significantly increase the organs-at-risk sparing in VMAT optimization for prostate carcinoma. In some particular cases, however, the DVH-based optimization resulted in superior treatment plans.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2012
Monitoring dosimetric impact of weight loss with kilovoltage (kV) cone beam CT (CBCT) during parotid-sparing IMRT and concurrent chemotherapy.
Parotid-sparing head-and-neck intensity-modulated radiotherapy (IMRT) can reduce long-term xerostomia. However, patients frequently experience weight loss and tumor shrinkage during treatment. We evaluate the use of kilovoltage (kV) cone beam computed tomography (CBCT) for dose monitoring and examine if the dosimetric impact of such changes on the parotid and critical neural structures warrants replanning during treatment. ⋯ Although patient weight loss and parotid volume shrinkage was observed, overall, there was no significant excess dose to the organs at risk. No replanning was felt necessary for this patient cohort, but a larger patient sample will be investigated to further confirm these results. Nevertheless, kilovoltage CBCT is a valuable tool for patient setup verification and monitoring of dosimetric variation during radiotherapy.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2012
Tumor shrinkage assessed by volumetric MRI in long-term follow-up after fractionated stereotactic radiotherapy of nonfunctioning pituitary adenoma.
To evaluate tumor control and side effects associated with fractionated stereotactic radiotherapy (FSRT) in the management of residual or recurrent nonfunctioning pituitary adenomas (NFPAs). ⋯ By using 3D MRI in all patients undergoing FSRT of an NFPA, tumor shrinkage is detected. Our data demonstrate that volumetric assessment based on 3D MRI adds additional information to routinely used radiological response measurements. After FSRT a mean relative size reduction of 51% can be expected within 5 years.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2012
Comparative StudyDosimetric comparison of combined intensity-modulated radiotherapy (IMRT) and proton therapy versus IMRT alone for pelvic and para-aortic radiotherapy in gynecologic malignancies.
To perform a dosimetric comparison of intensity-modulated radiotherapy (IMRT), passive scattering proton therapy (PSPT), and intensity-modulated proton therapy (IMPT) to the para-aortic (PA) nodal region in women with locally advanced gynecologic malignancies. ⋯ Compared with IMRT alone, PSPT/IMRT and IMPT/IMRT had a statistically significant decrease in dose to the small and large bowel and kidneys, while maintaining excellent planning target volume coverage. Further studies should be done to correlate the clinical significance of these findings.
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Int. J. Radiat. Oncol. Biol. Phys. · Mar 2012
Dynamic contrast-enhanced MRI of cervical cancers: temporal percentile screening of contrast enhancement identifies parameters for prediction of chemoradioresistance.
To systematically screen the tumor contrast enhancement of locally advanced cervical cancers to assess the prognostic value of two descriptive parameters derived from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). ⋯ The percentile-time screening identified DCE-MRI parameters that predict long-term locoregional control after chemoradiotherapy of cervical cancer.