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1.
Childs Nerv Syst ; 31(12): 2341-4, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26438548

RESUMEN

PURPOSE: Primary pediatric gliosarcoma (pPGS) is an extremely rare entity with only 25 cases reported in the English literature. The value of concurrent and adjuvant temozolomide is not known in this group of patient. METHODS: Five patients of pPGS treated from 2006 to 2011 were included in this retrospective analysis. All patients underwent maximal safe surgical resection. Adjuvant therapy included conformal radiation 60 Gy in 30 fractions (2 Gy daily for 5 days in a week) with concurrent temozolomide 75 mg/m(2) daily followed by six cycles of maintenance temozolomide 150-200 mg/m(2) (day 1 to day 5) every 4 weeks. We combined the survival data of 25 patients (already published) and five of our patients and analyzed them in terms of progression free survival (PFS) and overall survival (OS) using Kaplan-Meier method. RESULTS: Male to female ratio was 1:4 and median age was 12 years (range, 7-19 years). All but one patient underwent gross total resection and four patients completed adjuvant radiotherapy as well as concurrent and adjuvant temozolomide. At a median follow up of 22.6 months (range, 0 to 45.3 months), two patients were dead and two were alive without disease while one was lost to follow up. For the pooled data, estimated median PFS and OS of all 30 patients reported in literature were 12 and 43 months, respectively. Two years PFS and OS rate for all patients was 44.2 and 62.9%, respectively. CONCLUSION: Adjuvant radiotherapy and temozolomide is well tolerated and show an encouraging survival in pPGS.


Asunto(s)
Antineoplásicos Alquilantes/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/radioterapia , Dacarbazina/análogos & derivados , Gliosarcoma/tratamiento farmacológico , Gliosarcoma/radioterapia , Adolescente , Niño , Terapia Combinada , Dacarbazina/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Estudios Retrospectivos , Análisis de Supervivencia , Tasa de Supervivencia , Temozolomida , Adulto Joven
2.
J Synchrotron Radiat ; 19(Pt 1): 60-5, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22186645

RESUMEN

This feasibility work assesses the therapeutic effectiveness of minibeam radiation therapy, a new synchrotron radiotherapy technique. In this new approach the irradiation is performed on 9L gliosarcoma-bearing rats with arrays of parallel beams of width 500-700 µm. Two irradiation configurations were compared: a lateral unidirectional irradiation and two orthogonal arrays interlacing at the target. A dose escalation study was performed. A factor of three gain in the mean survival time obtained for some animals paves the way for further exploration of the different possibilities of this technique and its further optimization.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Gliosarcoma/radioterapia , Animales , Línea Celular Tumoral , Imagen por Resonancia Magnética , Masculino , Radiometría/métodos , Ratas , Ratas Endogámicas F344 , Tasa de Supervivencia , Sincrotrones
3.
J Pak Med Assoc ; 60(9): 773-5, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21381591

RESUMEN

Gliosarcoma is a rare variant of Glioblastoma Multiforme (GBM). It is a very aggressive tumour and usually managed like GBM. Treatment of choice is surgery with good surgical margins followed by radiotherapy (60 Gy). Median survival is seven months. Here we present a case report of 55 years old male who was diagnosed as brain tumour in left temporoparietal region. It turned out to be gliosarcoma after surgical resection and histopathological evaluation.


Asunto(s)
Neoplasias Encefálicas/cirugía , Glioblastoma/cirugía , Gliosarcoma/cirugía , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/radioterapia , Craneotomía , Resultado Fatal , Glioblastoma/patología , Glioblastoma/radioterapia , Gliosarcoma/patología , Gliosarcoma/radioterapia , Humanos , Inmunohistoquímica , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Radioterapia Conformacional
4.
Appl Radiat Isot ; 157: 109018, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31889683

RESUMEN

The current methodology for determining the biological effect of Boron Neutron Capture Therapy (BNCT) has recently been questioned, and a more accurate framework based in the photon iso-effective dose has been proposed. In this work we derive a first order approximation to this quantity. The new approach removes the main drawbacks of the current method, being based on new weighting factors which are true constants (dose independent) but which can be evaluated from published data on the existing (dose-dependent) weighting factors. In addition to this, we apply the formalism to allow the comparison to a fractionated conventional radiotherapy treatment, for which there is a lot of knowledge from clinical practice. As an application, the photon iso-effective dose of a BNCT treatment for a brain tumor is estimated. An excel sheet used for these calculations is also provided as supplementary material and can be used also with user-provided input data for the estimation of the photon iso-effective dose for comparison with conventional radiotherapy, both to single and fractionated treatments.


Asunto(s)
Terapia por Captura de Neutrón de Boro/métodos , Dosificación Radioterapéutica , Animales , Neoplasias Encefálicas/radioterapia , Relación Dosis-Respuesta en la Radiación , Gliosarcoma/radioterapia , Humanos , Fotones/uso terapéutico , Ratas
5.
Sci Rep ; 10(1): 8833, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32483249

RESUMEN

Synchrotron facilities produce ultra-high dose rate X-rays that can be used for selective cancer treatment when combined with micron-sized beams. Synchrotron microbeam radiation therapy (MRT) has been shown to inhibit cancer growth in small animals, whilst preserving healthy tissue function. However, the underlying mechanisms that produce successful MRT outcomes are not well understood, either in vitro or in vivo. This study provides new insights into the relationships between dosimetry, radiation transport simulations, in vitro cell response, and pre-clinical brain cancer survival using intracerebral gliosarcoma (9LGS) bearing rats. As part of this ground-breaking research, a new image-guided MRT technique was implemented for accurate tumor targeting combined with a pioneering assessment of tumor dose-coverage; an essential parameter for clinical radiotherapy. Based on the results of our study, we can now (for the first time) present clear and reproducible relationships between the in vitro cell response, tumor dose-volume coverage and survival post MRT irradiation of an aggressive and radioresistant brain cancer in a rodent model. Our innovative and interdisciplinary approach is illustrated by the results of the first long-term MRT pre-clinical trial in Australia. Implementing personalized synchrotron MRT for brain cancer treatment will advance this international research effort towards clinical trials.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Gliosarcoma/radioterapia , Animales , Encéfalo/patología , Encéfalo/efectos de la radiación , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Modelos Animales de Enfermedad , Gliosarcoma/mortalidad , Gliosarcoma/patología , Masculino , Ratas , Ratas Endogámicas F344 , Tasa de Supervivencia , Sincrotrones , Microtomografía por Rayos X , Rayos X
6.
Int J Radiat Oncol Biol Phys ; 108(3): 745-757, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32470502

RESUMEN

PURPOSE: Improved efficacy of anticancer therapy and a growing pool of survivors give rise to a question about their quality of life and return to premorbid status. Radiation is effective in brain metastasis eradication, although the optimal approach and long-term effects on brain function are largely unknown. We studied the effects of radiosurgery on brain function. METHODS AND MATERIALS: Adult C57BL/6J mice with or without brain metastases (rat 9L gliosarcoma) were treated with cone beam single-arc stereotactic radiosurgery (SRS; 40 Gy). Tumor growth was monitored using bioluminescence, whereas longitudinal magnetic resonance imaging, behavioral studies, and histologic analysis were performed to evaluate brain response to the treatment for up to 18 months. RESULTS: Stereotactic radiosurgery (SRS) resulted in 9L metastases eradication within 4 weeks with subsequent long-term survival of all treated animals, whereas all nontreated animals succumbed to the brain tumor. Behavioral impairment, as measured with a recognition memory test, was observed earlier in mice subjected to radiosurgery of tumors (6 weeks) in comparison to SRS of healthy brain tissue (10 weeks). Notably, the deficit resolved by 18 weeks only in mice not bearing a tumor, whereas tumor eradication was complicated by the persistent cognitive deficits. In addition, the results of magnetic resonance imaging were unremarkable in both groups, and histopathology revealed changes. SRS-induced tumor eradication triggered long-lasting and exacerbated neuroinflammatory response. No demyelination, neuronal loss, or hemorrhage was detected in any of the groups. CONCLUSIONS: Tumor disintegration by SRS leads to exacerbated neuroinflammation and persistent cognitive deficits; therefore, methods aiming at reducing inflammation after tumor eradication or other therapeutic methods should be sought.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Encéfalo/efectos de la radiación , Disfunción Cognitiva/etiología , Gliosarcoma/radioterapia , Radiocirugia/efectos adversos , Animales , Atención/efectos de la radiación , Conducta , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/secundario , Disfunción Cognitiva/diagnóstico por imagen , Encefalitis/diagnóstico por imagen , Encefalitis/etiología , Encefalitis/patología , Gliosarcoma/mortalidad , Gliosarcoma/patología , Gliosarcoma/secundario , Gliosis/etiología , Mediciones Luminiscentes , Activación de Macrófagos , Imagen por Resonancia Magnética/métodos , Masculino , Ratones , Ratones Endogámicos C57BL , Trasplante de Neoplasias/métodos , Radiocirugia/métodos , Dosificación Radioterapéutica , Reconocimiento en Psicología
7.
Neuro Oncol ; 11(2): 183-91, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18780813

RESUMEN

The epidemiology and natural history of adult gliosarcomas (GSMs), as well as patient and treatment factors associated with outcome, are ill defined. Patients over 20 years of age with GSM diagnosed from 1988 to 2004 were identified in the Surveillance, Epidemiology, and End Results (SEER) database. Kaplan-Meier survival analysis and Cox models were used to examine outcomes. Similar analyses were conducted for patients diagnosed with glioblastoma (GBM) over the same time period. GSM represented 2.2% of the 16,388 patients identified with either GSM or GBM. No significant differences between GSM and GBM were identified with respect to age, gender, race, tumor size, or use of adjuvant radiation therapy (RT). Patients with GSM were more likely to have temporal lobe involvement and undergo some form of tumor resection. The most important analyzed factors influencing GSM overall survival were age, extent of resection, and use of adjuvant RT. After adjusting for factors impacting overall survival, the prognosis for GSM appears slightly worse than for GBM (HR = 1.17, 95% CI, 1.05-1.31). GSM is a rare malignancy that presents very similarly to GBM with a slightly greater propensity for temporal lobe involvement. Optimal treatment remains to be defined. However, these retrospective findings suggest tumor excision, as opposed to biopsy only, and adjuvant RT may improve outcome. Despite therapy, prognosis remains dismal and outcomes may be inferior to those seen in GBM patients.


Asunto(s)
Neoplasias Encefálicas/epidemiología , Gliosarcoma/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Encefálicas/radioterapia , Femenino , Gliosarcoma/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Evaluación de Resultado en la Atención de Salud , Pronóstico , Radioterapia Adyuvante , Programa de VERF , Tasa de Supervivencia , Resultado del Tratamiento , Adulto Joven
8.
J Synchrotron Radiat ; 16(Pt 4): 587-90, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19535875

RESUMEN

The technical feasibility of temporal and spatial fractionations of the radiation dose has been evaluated using synchrotron microbeam radiation therapy for brain tumors in rats. A significant increase in lifespan (216%, p < 0.0001) resulted when three fractions of microbeam irradiation were applied to the tumor through three different ports, orthogonal to each other, at 24 h intervals. However, there were no long-term survivors, and immunohistological studies revealed that 9 L tumors were not entirely ablated.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Gliosarcoma/radioterapia , Dosificación Radioterapéutica , Sincrotrones , Animales , Masculino , Ratas , Ratas Endogámicas F344
9.
Phys Med Biol ; 53(4): 861-78, 2008 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-18263945

RESUMEN

The purpose of this work was the understanding of microbeam radiation therapy at the ESRF in order to find the best compromise between curing of tumors and sparing of normal tissues, to obtain a better understanding of survival curves and to report its efficiency. This method uses synchrotron-generated x-ray microbeams. Rats were implanted with 9L gliosarcomas and the tumors were diagnosed by MRI. They were irradiated 14 days after implantation by arrays of 25 microm wide microbeams in unidirectional mode, with a skin entrance dose of 625 Gy. The effect of using 200 or 100 microm center-to-center spacing between the microbeams was compared. The median survival time (post-implantation) was 40 and 67 days at 200 and 100 microm spacing, respectively. However, 72% of rats irradiated at 100 microm spacing showed abnormal clinical signs and weight patterns, whereas only 12% of rats were affected at 200 microm spacing. In parallel, histological lesions of the normal brain were found in the 100 microm series only. Although the increase in lifespan was equal to 273% and 102% for the 100 and 200 microm series, respectively, the 200 microm spacing protocol provides a better sparing of healthy tissue and may prove useful in combination with other radiation modalities or additional drugs.


Asunto(s)
Cerebro/patología , Irradiación Craneana/métodos , Gliosarcoma/radioterapia , Sincrotrones , Animales , Peso Corporal , Línea Celular Tumoral , Gliosarcoma/diagnóstico , Gliosarcoma/patología , Imagen por Resonancia Magnética , Masculino , Trasplante de Neoplasias , Ratas , Tasa de Supervivencia , Resultado del Tratamiento
10.
Phys Med Biol ; 53(13): 3609-22, 2008 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-18560052

RESUMEN

The aim of this work focuses on the description of the short-term response of a 9L brain tumor model and its vasculature to microbeam radiation therapy (MRT) using magnetic resonance imaging (MRI). Rat 9L gliosarcomas implanted in nude mice brains were irradiated by MRT 13 days after tumor inoculation using two orthogonal arrays of equally spaced 28 planar microbeams (25 microm width, 211 microm spacing and dose 500 Gy). At 1, 7 and 14 days after MRT, apparent diffusion coefficient, blood volume and vessel size index were mapped by MRI. Mean survival time after tumor inoculation increased significantly between MRT-treated and untreated groups (23 and 28 days respectively, log-rank test, p < 0.0001). A significant increase of apparent diffusion coefficient was observed 24 h after MRT in irradiated tumors versus non-irradiated ones. In the untreated group, both tumor size and vessel size index increased significantly (from 7.6 +/- 2.2 to 19.2 +/- 4.0 mm(2) and +23%, respectively) between the 14th and the 21st day after tumor cell inoculation. During the same period, in the MRT-treated group, no difference in tumor size was observed. The vessel size index measured in the MRT-treated group increased significantly (+26%) between 14 and 28 days of tumor growth. We did not observe the significant difference in blood volume between the MRT-treated and untreated groups. MRT slows 9L tumor growth in a mouse brain but MRI results suggest that the increase in survival time after our MRT approach may be rather due to a cytoreduction than to early direct effects of ionizing radiation on tumor vessels. These results suggest that MRT parameters need to be optimized to further damage tumor vessels.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Gliosarcoma/radioterapia , Neovascularización Patológica/radioterapia , Radioterapia/métodos , Sincrotrones , Animales , Neoplasias Encefálicas/patología , Gliosarcoma/patología , Imagen por Resonancia Magnética/métodos , Masculino , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Neovascularización Patológica/patología , Radioterapia/instrumentación , Dosificación Radioterapéutica , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
11.
Tumori ; 94(4): 493-6, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18822684

RESUMEN

AIMS AND BACKGROUND: Gliosarcomas are rare malignant primary brain tumors that usually affect the fifth or sixth decades of life. The purpose of this study was to describe our experience with such lesions in elderly patients and to establish their prognosis factors. METHODS: Between 1993 and 2001, 7 patients over 60 years of age were treated at our institute for cerebral gliosarcomas. All patients underwent surgery for total or at least sub-total removal of a neoplastic mass. RESULTS: Owing to poor clinical conditions (Karnofsky performance score = 40), one patient was not treated postoperatively. Remaining patients were treated with whole-brain radiotherapy, whereas concomitant chemotherapy (temozolomide) was administrated only to 4 patients. Histological examination showed the prevalence of sarcomatous aspects in 3 patients; the gliomatous aspect prevailed in 4 patients. CONCLUSIONS: Sarcomatous aspects and multimodality treatment (surgery, radiotherapy and chemotherapy) were associated with a better prognosis and showed in these elderly patients a trend similar to that of young people.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/terapia , Gliosarcoma/diagnóstico , Gliosarcoma/terapia , Anciano , Anciano de 80 o más Años , Antineoplásicos Alquilantes/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirugía , Quimioterapia Adyuvante , Dacarbazina/análogos & derivados , Dacarbazina/uso terapéutico , Femenino , Gliosarcoma/tratamiento farmacológico , Gliosarcoma/patología , Gliosarcoma/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Radioterapia Adyuvante , Estudios Retrospectivos , Temozolomida
12.
Clin Neuropathol ; 25(4): 200-3, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16866302

RESUMEN

Gliosarcoma is a highly malignant brain tumor consisting of both a glioblastoma and a mesenchymal component. The latter typically resembles fibrosarcoma, but differentiation patterns resembling osteosarcoma, chondrosarcoma, angiosarcoma and rhabdomyosarcoma have also been described. Molecular-genetic studies have shown that both glioblastoma and the mesenchymal component share identical cytogenetic abnormalities or mutations, suggesting a monoclonal origin from glial cells. We report an unusual case of gliosarcoma that presented as a large intracerebral tumor with infiltration of the temporal bone and the soft tissues in the infratemporal fossa. Microscopically, the tumor consisted of alternating areas of glioblastoma and fibrosarcoma. Focally, areas ofosteosarcomatous and liposarcomatous differentiation were found. Although gliosarcoma with transcranial penetration is very rare, it should be suspected in case of intracranial tumor with glioblastoma-imaging features, infiltration of bone and extracranial growth. Our case of liposarcomatous differentiation in gliosarcoma--together with another very recently reported similar case--expands the morphologic heterogeneity of this peculiar brain tumor.


Asunto(s)
Neoplasias Óseas/patología , Neoplasias Encefálicas/patología , Gliosarcoma/patología , Liposarcoma/patología , Hueso Temporal/patología , Neoplasias Óseas/radioterapia , Neoplasias Óseas/cirugía , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirugía , Gliosarcoma/radioterapia , Gliosarcoma/cirugía , Humanos , Liposarcoma/radioterapia , Liposarcoma/cirugía , Masculino , Persona de Mediana Edad , Hueso Temporal/cirugía , Resultado del Tratamiento
13.
Cancer Res ; 61(22): 8179-87, 2001 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11719448

RESUMEN

Boron neutron capture therapy (BNCT) is dependent on the selective accumulation of boron-10 in tumor cells relative to the contiguous normal cells. Ion microscopy was used to evaluate the microdistribution of boron-10 from p-boronophenylalanine (BPA) in the 9L rat gliosarcoma and the F98 rat glioma brain tumor models. Four routes of BPA administration were used: i.p. injection, intracarotid (i.c.) injection [with and without blood-brain barrier disruption (BBB-D)], and continuous timed i.v. infusions. i.p. injection of BPA in the 9L gliosarcoma resulted in a tumor-to-brain (T:Br) boron-10 concentration ratio of 3.7:1 when measured at the tumor-normal brain interface. In the F98 glioma, i.c injection of BPA resulted in a T:Br ratio of 2.9:1, and this increased to 5.4:1 when BBB-D was performed. The increased tumor boron uptake would potentially enhance the therapeutic ratio of BNCT by >25%. At present, ion microscopy is the only technique to provide a direct measurement of the T:Br boron-10 concentration ratio for tumor cells infiltrating normal brain. In the 9L gliosarcoma, this ratio was 2.9:1 after i.p. administration. In the F98 glioma, i.c injection resulted in a ratio of 2.2:1, and this increased to 3.0:1 after BBB-D. Ion microscopy revealed a consistent pattern of boron-10 microdistribution for both rat brain tumor models. The boron-10 concentration in the main tumor mass (MTM) was approximately twice that of the infiltrating tumor cells. One hour after a 2-h i.v. infusion of BPA in rats with the 9L gliosarcoma, tumor boron-10 concentrations were 2.7 times higher than that of infiltrating tumor cells [83 +/- 23 microg/g tissue versus 31 +/- 12 microg/g tissue (mean +/- SD)]. Continuous 3- and 6-h i.v. infusions of BPA in the 9L gliosarcoma resulted in similar high boron-10 concentrations in the MTM. The boron-10 concentration in infiltrating tumor cells was two times lower than the MTM after a 3-h infusion. After 6 h, the boron-10 concentration in infiltrating tumor cells had increased nearly 90% relative to the 2- and 3-h infusions. A 24-h i.v. infusion resulted in similar boron-10 levels between the MTM and the infiltrating tumor cells. Boron concentrations in the normal brain were similar for all four infusion times (approximately 20 microg/g tissue). These results are important for BNCT, because clinical protocols using a 2-h infusion have been performed with the assumption that infiltrating tumor cells contain equivalent amounts of boron-10 as the MTM. The results reported here suggest that this is not the case and that a 6-h or longer infusion of BPA may be necessary to raise boron-10 levels in infiltrating tumor cells to that in the MTM.


Asunto(s)
Compuestos de Boro/farmacocinética , Boro/farmacocinética , Neoplasias Encefálicas/metabolismo , Gliosarcoma/patología , Fenilalanina/análogos & derivados , Fenilalanina/farmacocinética , Animales , Boro/uso terapéutico , Compuestos de Boro/uso terapéutico , Terapia por Captura de Neutrón de Boro , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/radioterapia , Esquema de Medicación , Gliosarcoma/metabolismo , Gliosarcoma/radioterapia , Infusiones Intravenosas , Isótopos , Masculino , Fenilalanina/uso terapéutico , Ratas , Ratas Endogámicas F344 , Espectrometría de Masa de Ion Secundario/métodos
14.
Sci Rep ; 6: 29678, 2016 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-27411781

RESUMEN

We recently developed the synthesis of ultrasmall gadolinium-based nanoparticles (GBN), (hydrodynamic diameter <5 nm) characterized by a safe behavior after intravenous injection (renal clearance, preferential accumulation in tumors). Owing to the presence of gadolinium ions, GBN can be used as contrast agents for magnetic resonance imaging (MRI) and as radiosensitizers. The attempt to determine the most opportune delay between the intravenous injection of GBN and the irradiation showed that a very low content of radiosensitizing nanoparticles in the tumor area is sufficient (0.1 µg/g of particles, i.e. 15 ppb of gadolinium) for an important increase of the therapeutic effect of irradiation. Such a promising and unexpected result is assigned to a suited distribution of GBN within the tumor, as revealed by the X-ray fluorescence (XRF) maps.


Asunto(s)
Gadolinio/administración & dosificación , Gliosarcoma/radioterapia , Nanopartículas/administración & dosificación , Fármacos Sensibilizantes a Radiaciones/administración & dosificación , Animales , Línea Celular , Medios de Contraste/administración & dosificación , Imagen por Resonancia Magnética/métodos , Masculino , Ratas , Ratas Endogámicas F344 , Rayos X
15.
Phys Med ; 32(12): 1852-1861, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27866898

RESUMEN

Microbeam Radiation Therapy (MRT) exploits tumour selectivity and normal tissue sparing with spatially fractionated kilovoltage X-ray microbeams through the dose volume effect. Experimental measurements with Ta2O5 nanoparticles (NPs) in 9L gliosarcoma treated with MRT at the Australian Synchrotron, increased the treatment efficiency. Ta2O5 NPs were observed to form shells around cell nuclei which may be the reason for their efficiency in MRT. In this article, our experimental observation of NP shell formation is the basis of a Geant4 radiation transport study to characterise dose enhancement by Ta2O5 NPs in MRT. Our study showed that NP shells enhance the physical dose depending microbeam energy and their location relative to a single microbeam. For monochromatic microbeam energies below ∼70keV, NP shells show highly localised dose enhancement due to the short range of associated secondary electrons. Low microbeam energies indicate better targeted treatment by allowing higher microbeam doses to be administered to tumours and better exploit the spatial fractionation related selectivity observed with MRT. For microbeam energies above ∼100keV, NP shells extend the physical dose enhancement due to longer-range secondary electrons. Again, with NPs selectively internalised, the local effectiveness of MRT is expected to increase in the tumour. Dose enhancement produced by the shell aggregate varied more significantly in the cell population, depending on its location, when compared to a homogeneous NP distribution. These combined simulation and experimental data provide first evidence for optimising MRT through the incorporation of newly observed Ta2O5 NP distributions within 9L cancer cells.


Asunto(s)
Microtecnología/instrumentación , Nanopartículas , Óxidos/química , Óxidos/farmacología , Dosis de Radiación , Radioterapia/instrumentación , Sincrotrones , Tantalio/química , Tantalio/farmacología , Neoplasias Encefálicas/radioterapia , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Gliosarcoma/radioterapia , Humanos , Método de Montecarlo , Fármacos Sensibilizantes a Radiaciones/química , Fármacos Sensibilizantes a Radiaciones/farmacología , Dosificación Radioterapéutica
16.
Int J Radiat Oncol Biol Phys ; 63(2): 511-9, 2005 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-16168843

RESUMEN

PURPOSE: To develop a valid treatment strategy for recurrent high-grade gliomas using stereotactic hypofractionated reirradiation based on biologic imaging and temozolomide. PATIENTS AND METHODS: The trial included a total of 44 patients with recurrent high-grade gliomas (1 patient with anaplastic oligodendroglioma, 8 with anaplastic astrocytoma, 33 with glioblastoma multiforme, and 2 with gliosarcoma) after previous surgery and postoperative conventional radiotherapy +/- chemotherapy. For fractionated stereotactic radiotherapy (SFRT) treatment planning, the gross tumor volume was defined by (11)C-methionine positron emission tomography (MET-PET) or (123)I-alpha-methyl-tyrosine (IMT) single-photon computed emission tomography (SPECT)/computed tomography (CT)/magnetic resonance imaging (MRI) fusion in 82% of the patients and by CT/T1+gadolinium-MRI image fusion in 18% of the patients. Six fractions of 5 Gy were administered in 6 days. In 29 of 44 patients (66%), chemotherapy with temozolomide (200 mg/m(2) body surface/day) was given in one to two cycles before and four to five cycles after SFRT. The patients were evaluated in follow-up by clinical investigators and MRI or CT every 3 months after SFRT until death. In cases suspicious for radiation necrosis, a MET-PET or IMT-SPECT investigation was performed. RESULTS: The median survival time in the whole group was 8 months. Treatment planning based on PET(SPECT)/CT/MRI imaging was associated with improved survival in comparison to treatment planning using CT/MRI alone: median survival time 9 months vs. 5 months (p = 0.03, log-rank). Median survival time were 11 months for patients who received SFRT based on biologic imaging plus temozolomide and significantly lower, 6 months for patients treated with SFRT without biologic imaging, without temozolomide or without both (p = 0.008, log rank). The most important prognostic factor in univariate analysis was a long interval between initial diagnosis and recurrence (p = 0.0002, log-rank). In the multivariate model, time interval to retreatment (p = 0.006) and temozolomide (p = 0.04) remained statistically significant. No acute neurologic toxicity Grade 3 or higher and no Grade 4 hematologic toxicity was observed. CONCLUSION: This is the first study of biologic imaging optimized SFRT plus temozolomide in recurrent high-grade gliomas. It demonstrates the feasibility and safety of this approach. The most striking result of the trial is the statistically significant longer survival time in the univariate analysis for patients reirradiated using MET-PET or IMT-SPECT/CT/MRI image fusion in the treatment planning, in comparison to patients treated based on MRI/CT alone. Multivariate analysis confirmed a significant survival benefit from multimodal treatment (i.e., addition of temozolomide), despite the limited number of patients. Whether treatment planning with SPECT/PET independently influences survival has to be studied in a larger series of patients.


Asunto(s)
Glioma/tratamiento farmacológico , Glioma/radioterapia , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/radioterapia , Adulto , Anciano , Análisis de Varianza , Antineoplásicos Alquilantes/uso terapéutico , Astrocitoma/diagnóstico por imagen , Astrocitoma/tratamiento farmacológico , Astrocitoma/radioterapia , Terapia Combinada , Dacarbazina/análogos & derivados , Dacarbazina/uso terapéutico , Fraccionamiento de la Dosis de Radiación , Femenino , Glioblastoma/diagnóstico por imagen , Glioblastoma/tratamiento farmacológico , Glioblastoma/radioterapia , Glioma/diagnóstico por imagen , Gliosarcoma/diagnóstico por imagen , Gliosarcoma/tratamiento farmacológico , Gliosarcoma/radioterapia , Humanos , Masculino , Metionina , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Oligodendroglioma/diagnóstico por imagen , Oligodendroglioma/tratamiento farmacológico , Oligodendroglioma/radioterapia , Tomografía de Emisión de Positrones/métodos , Estudios Prospectivos , Estadísticas no Paramétricas , Técnicas Estereotáxicas , Temozolomida , Tomografía Computarizada de Emisión de Fotón Único/métodos , alfa-Metiltirosina
17.
J Neurosurg ; 103(6): 1000-9, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16381186

RESUMEN

OBJECT: To improve the effectiveness of boron neutron capture therapy (BNCT) for malignant gliomas, the authors used epithermal rather than thermal neutrons for deep penetration and two boron compounds-sodium borocaptate (BSH) and boronophenylalanine (BPA)-with different accumulation mechanisms to increase the boron level in tumors while compensating for each other's faults. METHODS: Thirteen patients, 10 of whom harbored a glioblastoma multiforme (GBM), one a gliosarcoma, one an anaplastic astrocytoma, and one an anaplastic oligoastrocytoma, were treated using this modified BNCT between January 2002 and December 2003. Postoperatively, neuroimaging revealed that only one patient with a GBM had no lesion enhancement postoperatively. The patients underwent 18F-BPA positron emission tomography, if available, to assess the accumulation and distribution of BPA before neutron radiotherapy. The neutron fluence rate was estimated using the Simulation Environments for Radiotherapy Applications dose-planning system before irradiation. The patients' volume assessments were performed using magnetic resonance (MR) imaging or computerized tomography (CT) scanning. Improvements in the disease as seen on neuroimages were assessed between 2 and 7 days after irradiation to determine the initial effects of BNCT; its maximal effects were also analyzed on serial neuroimages. The mean tumor volume before BNCT was 42.3 cm3. Regardless of the pre-BNCT tumor volume, in every patient harboring an assessable lesion, improvements on MR or CT images were recognized both at the initial assessment (range of volume reduction rate 17.4-71%, mean rate 46.4%) and at follow-up assessments (range of volume reduction rates 30.3-87.6%, mean rate 58.5%). More than 50% of the contrast-enhanced lesions disappeared in eight of the 12 patients during the follow-up period. CONCLUSIONS: This modified BNCT produced a good improvement in malignant gliomas, as seen on neuroimages.


Asunto(s)
Terapia por Captura de Neutrón de Boro/métodos , Neoplasias Encefálicas/radioterapia , Glioma/radioterapia , Imagen por Resonancia Magnética , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Adulto , Anciano , Astrocitoma/radioterapia , Compuestos de Boro/uso terapéutico , Terapia por Captura de Neutrón de Boro/efectos adversos , Edema Encefálico/diagnóstico , Edema Encefálico/etiología , Neoplasias Encefálicas/complicaciones , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patología , Femenino , Glioblastoma/radioterapia , Glioma/complicaciones , Glioma/diagnóstico , Glioma/patología , Gliosarcoma/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Neutrones , Resultado del Tratamiento
18.
Clin Cancer Res ; 3(11): 2081-8, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9815600

RESUMEN

The efficacy of HSV-1 thymidine kinase (TK) and Escherichia coli cytosine deaminase (CD) suicide gene therapies as cancer treatments are currently being examined in humans. We demonstrated previously that compared to single suicide gene therapy, greater levels of targeted cytotoxicity and radiosensitization can be achieved in vitro by genetically modifying tumor cells to express CD and HSV-1 TK concomitantly, as a fusion protein. In the present study, the efficacy of the combined double suicide gene therapy/radiotherapy approach was examined in vivo. Nude mice were injected either s.c. or i.m. with 9L gliosarcoma cells expressing an E. coli CD/HSV-1 TK fusion gene. Double suicide gene therapy using 5-fluorocytosine (500 mg/kg) and ganciclovir (30 mg/kg) proved to be markedly better at delaying tumor growth and achieving a tumor cure than single suicide gene therapy, which used 5-fluorocytosine or ganciclovir administered independently. Importantly, double suicide gene therapy was highly effective against large experimental tumors (>2 cm3), reducing tumor volume an average of 99% and producing a 40% tumor cure. Moreover, double suicide gene therapy profoundly potentiated the antitumor effects of radiation. The results indicate that double suicide gene therapy, particularly when coupled with radiotherapy, may represent a highly effective means of eradicating tumors.


Asunto(s)
Flucitosina/uso terapéutico , Ganciclovir/uso terapéutico , Terapia Genética , Gliosarcoma/radioterapia , Gliosarcoma/terapia , Timidina Quinasa/genética , Animales , Terapia Combinada , Gliosarcoma/tratamiento farmacológico , Gliosarcoma/patología , Herpesvirus Humano 1/genética , Ratones , Ratones Desnudos , Profármacos/uso terapéutico , Ratas , Proteínas Recombinantes de Fusión/antagonistas & inhibidores , Proteínas Recombinantes de Fusión/biosíntesis , Timidina Quinasa/antagonistas & inhibidores , Factores de Tiempo , Trasplante Heterólogo , Células Tumorales Cultivadas
19.
J Cancer Res Ther ; 11(3): 651, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26458625

RESUMEN

Gliosarcoma is a rare primary malignant tumor of the central nervous system with poor prognosis. The median survival time of this disease ranges from 6 months to 14.8 months. However, a computer literature search indicated few long-term survivors. We investigated a case of a survivor of gliosarcoma with radiation-induced meningeal sarcomas, who showed no indication of recurrence for more than 9 years. A battery of molecular studies was performed to develop a molecular profile of this unique patient. We also reviewed the distinct clinical and molecular features of the tumor.


Asunto(s)
Gliosarcoma/radioterapia , Neoplasias Meníngeas/radioterapia , Neoplasias Inducidas por Radiación/patología , Adulto , Metilasas de Modificación del ADN , Enzimas Reparadoras del ADN , Supervivencia sin Enfermedad , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Gliosarcoma/diagnóstico por imagen , Gliosarcoma/genética , Gliosarcoma/patología , Humanos , Isocitrato Deshidrogenasa/genética , Imagen por Resonancia Magnética , Masculino , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/patología , Neoplasias Inducidas por Radiación/genética , Fosfohidrolasa PTEN/biosíntesis , Radiografía , Resultado del Tratamiento , Proteínas Supresoras de Tumor
20.
Brain Pathol ; 9(2): 421-2, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10219754

RESUMEN

In Jan. 97 a gliosarcoma was diagnosed in a 61-year- old man after a 6-month history with neurological deficits. A total physical examination, laboratory tests, chest x-ray and abdominal ultrasound scanning revealed no gross abnormalities. Surgery was followed by brain radiation therapy and 6 months later there were metastases to the oral cavity, right palpebra and both lungs. The histological findings of the oral and palpebral metastases revealed only the sarcomatous component. We are aware of 15 cases of gliosarcoma with extraneural metastases, and in 4 of these, the metastases contained only the sarcomatous component. We believe that our case represents the fifth case of pure sarcomatous metastases.


Asunto(s)
Neoplasias Encefálicas/patología , Neoplasias de los Párpados/secundario , Gliosarcoma/patología , Gliosarcoma/secundario , Neoplasias Pulmonares/secundario , Neoplasias de la Boca/secundario , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirugía , Neoplasias de los Párpados/patología , Gliosarcoma/radioterapia , Gliosarcoma/cirugía , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/patología
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