Enhancement of survival of 9L gliosarcoma bearing rats following intracerebral delivery of drugs in combination with microbeam radiation therapy.
Eur J Radiol
; 68(3 Suppl): S151-5, 2008 Dec.
Article
em En
| MEDLINE
| ID: mdl-18635331
ABSTRACT
Microbeam radiation therapy (MRT) is a form of radiosurgery first dedicated to the treatment of brain tumors. It uses arrays of synchrotron generated X-rays microbeams of very high doses (typically 625 Gy). Microbeams are typically few micrometers large (25 microm) and few hundred micrometers spaced (200 microm). Previous experiments have shown that despite a good tumor eradication rate (5/11), a 100-microm spacing unidirectional irradiation (skin dose 625 Gy, width 25 microm) was too invasive for normal tissue. On the contrary, a 200-microm spacing unidirectional irradiation preserved healthy tissue with a low tumor eradication rate (2/32). The purpose of this study was to enhance the potential of the 200 microm spacing irradiation protocol. After diagnosis of the tumor by MRI, 9L tumor-bearing rats were laterally irradiated with 51 microbeams (625 Gy, 25 microm, 200 microm) 14 days after implantation. Three drugs (Gd-DTPA, CisPt, temozolomide) were tested, after intratumoral injection at the theoretical center of the tumor. Control rats displayed a median survival time of 19 days. There was no significant difference between drug-treated rats and control group. Irradiated animals showed an increase in life span (ILS) of 60.5%. Interestingly, the ILS increased to 131.6% and 1/6 rat survived more than 1 year in case of MRT combined with gadolinium injection. These results showed that the synergy between gadolinium injection (acting as a dose enhancer) and MRT improved significantly the life span of tumor bearing rats (more than a factor 2).
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Neoplasias Encefálicas
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Taxa de Sobrevida
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Radioterapia de Alta Energia
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Síncrotrons
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Gliossarcoma
Tipo de estudo:
Guideline
Limite:
Animals
Idioma:
En
Revista:
Eur J Radiol
Ano de publicação:
2008
Tipo de documento:
Article
País de afiliação:
França