Radiation treatment planning with an integrated positron emission and computer tomography (PET/CT): a feasibility study.
Int J Radiat Oncol Biol Phys
; 57(3): 853-63, 2003 Nov 01.
Article
em En
| MEDLINE
| ID: mdl-14529793
ABSTRACT
PURPOSE:
To investigate the usefulness of hardware coregistered PET/CT images for target volume definition. METHODS AND MATERIALS Thirty-nine patients presenting with various solid tumors were investigated. CT and a FDG-PET were obtained in treatment position in an integrated PET/CT scanner, and coregistered images were used for treatment planning. First, volume delineation was performed on the CT data. In a second step, the corresponding PET data were used as an overlay to the CT data to define the target volume. Delineation was done independently by two investigators.RESULTS:
Coregistered PET/CT showed good fusion accuracy. The GTV increased by 25% or more because of PET in 17% of cases with head-and-neck (2/12) and lung cancer (1/6), and in 33% (7/21) in cancer of the pelvis. The GTV was reduced > or =25% in 33% of patients with head-and-neck cancer (4/12), in 67% with lung cancer (4/6), and 19% with cancer of the pelvis (4/21). Overall, in 56% (22/39) of cases, GTV delineation was changed significantly if information from metabolic imaging was used in the planning process. The modification of the GTV translated into altered PTV changes exceeding >20% in 46% (18/39) of cases. With PET, volume delineation variability between two independent oncologists decreased from a mean volume difference of 25.7 cm(3) to 9.2 cm(3) associated with a reduction of the standard deviation from 38.3 cm(3) to 13.3 cm(3) (p = 0.02). In 16% of cases, PET/CT revealed distant metastasies, changing the treatment strategy from curative to palliative.CONCLUSION:
Integrated PET/CT for treatment planning for three-dimensional conformal radiation therapy improves the standardization of volume delineation compared with that of CT alone. PET/CT has the potential for reducing the risk for geographic misses, to minimize the dose of ionizing radiation applied to non-target organs, and to change the current practice to three-dimensional conformal radiation therapy planning by taking into account the metabolic and biologic features of cancer. The impact on treatment outcome remains to be demonstrated.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Planejamento da Radioterapia Assistida por Computador
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Tomografia Computadorizada de Emissão
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Tomografia Computadorizada por Raios X
/
Neoplasias
Limite:
Adult
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Aged
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Aged80
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Int J Radiat Oncol Biol Phys
Ano de publicação:
2003
Tipo de documento:
Article
País de afiliação:
Suíça