Role of adaptive radiation therapy for pediatric patients with diffuse pontine glioma.
J Appl Clin Med Phys
; 12(2): 3421, 2011 Jan 30.
Article
em En
| MEDLINE
| ID: mdl-21587190
ABSTRACT
We investigate the role of adaptive radiation therapy in pediatric patients with diffuse pontine glioma and the impact of steroid-related weight gain on treatment parameters utilizing cone-beam CT. Fifteen patients with diffuse pontine glioma were treated with three-dimensional conformal radiation therapy and enrolled on a daily localization protocol. The median age was 6 years (range 2-13 years). Patient charts were examined to obtain the prescribed daily dose of dexamethasone and weight. The original treatment plan was recalculated based on the data obtained from the daily cone-beam CT. The changes in target and critical structure doses were calculated using gEUD. Correlations between prescribed dexamethasone, weight gain, source-to-skin distance (SSD) changes and dosimetric changes were investigated. Eleven of the 15 patients gained weight during radiation therapy, with an average gain of 2.2 kg (8.0%). The mean gEUD decreased was 0.57 Gy (range 0.24-1.4 Gy) for the PTV, and the mean gEUD increase for critical structures was 1.14%. No strong correlations between prescribed dexamethasone doses, weight gain and dosimetric changes were found. Change in SSD vs. dose to PTV was correlated (R² = 0.51). Weight gain and changes to the external surface are apparent in these patients; however, the dosimetric changes to the target and critical structures were small and in most cases did not warrant an adaptive plan. The potential exists for a decrease in target dose in these patients; therefore, they should be monitored to assess for replanning when necessary.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Radioterapia
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Neoplasias Encefálicas
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Neoplasias do Tronco Encefálico
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Tomografia Computadorizada de Feixe Cônico
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article
País de afiliação:
Estados Unidos