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1.
Health Sci Rep ; 5(4): e571, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35769357

RESUMO

Objective: The main purpose of this study was to carry out a global risk analysis (GRA) on the subcontracting circuit to determine and evaluate the risks linked to the future subcontracting process and to propose corrective actions for the most critical risks to ensure safety. This study must allow to conclude in an objective way to the feasibility or not of this project. Methods: A GRA was performed, conducted by a multidisciplinary working group that met in 20 meetings, corresponding to about 50 h of work. Results: We identified 92 scenarios: 13% of scenarios had an initial criticality C1, 40% C2, and 47% C3. The GRA shows that the riskiest scenarios concern the management, material, and equipment with IT system and logistics with transport. The working group identified 25 corrective actions. After implementing those actions, 85% of scenarios had residual criticality C1, 8.5% C2, and 6.5% had residual criticality C3. The working group chose that it was impossible to subcontract part of the activity. Conclusion: The GRA conducted in this study highlighted the risks related to outsourcing this activity, evaluated and prioritized them, and recommended corrective actions. Therefore, we conclude that subcontracting the totality of sterile preparations would be harmful to patient care quality and reactivity for vital medical emergencies, such as macrophage activation syndrome, preparation of clinical trials, graft rejection therapies, preparation of very short stability chemotherapy, and the pediatric graft conditioning chemotherapy.

2.
Arch Cardiovasc Dis ; 115(5): 295-304, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35527210

RESUMO

BACKGROUND: In patients undergoing balloon pulmonary angioplasty (BPA) for inoperable chronic thromboembolic pulmonary hypertension (CTEPH), single-centre series from expert centres have recognized a learning curve for the magnitude of haemodynamic benefits. OBJECTIVE: To report our 7-year experience with BPA, focusing on haemodynamic effects, complication rates and radiation exposure over time. METHODS: Patients with CTEPH who were treated with BPA between May 2013 and February 2020 were analysed during the 'initial period' versus the 'recent period' (split date: March 2017). RESULTS: Among 192 patients who underwent at least one BPA procedure, 156 were included in the safety/radiation analysis and 119 were included in the efficacy analysis. During the 'recent period' versus the 'initial period', the median [interquartile range] number of procedures per patient was higher (4.5 [4.0-6.0] vs. 4.0 [3.0-4.0]; P=0.03), as was the number of dilated vessels per procedure (4.0 [3.5-5.0] vs. 3.5 [3.0-4.0]; P=0.002). Changes in haemodynamic parameters were also greater (mean pulmonary artery pressure: -22% [-31% to -14%] vs. -37% [-44% to -29%]; P=0.001; pulmonary vascular resistance: -38% [-51% to -8%] vs. -53% [-69% to -33%]; P=0.002); complication rates were similar (5.7% vs. 9.3% of procedures; P=0.38); and radiation exposure was lower (effective dose per patient: 43.9 [31.6-66.5] vs. 67.8 [47.9-101.9] mSv; P<0.001). CONCLUSION: Our analysis is consistent with a learning curve for the magnitude of haemodynamic improvements. The complication rate was low and did not change over time, but radiation exposure decreased.


Assuntos
Angioplastia com Balão , Hipertensão Pulmonar , Embolia Pulmonar , Exposição à Radiação , Angioplastia com Balão/efeitos adversos , Doença Crônica , Hemodinâmica , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/terapia , Artéria Pulmonar , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/terapia , Exposição à Radiação/efeitos adversos , Resultado do Tratamento
3.
Eur J Hosp Pharm ; 29(5): 284-286, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-32978219

RESUMO

Risk management for workers involved in the handling and preparation of cytotoxic drugs is challenging. This study aims to investigate drug contamination of the exterior surfaces of cytotoxic drug vials. Two batches of commercially available cytotoxic drugs in unprotected vials (ifosfamide, etoposide phosphate and cyclophosphamide) and plastic shrink wrap vials (doxorubicin, cytarabine and busulfan) were tested without removing the flip-off cap or the plastic wrap, and without prewashing. The results showed significant trace amounts of cytotoxic drugs on the exterior surfaces in both unprotected (eg, cyclophosphamide, ifosfamide) and protected plastic shrink wrap vials (eg, cytarabine), indicating that the secondary packaging of protected vials does not systematically prevent exposure to the handlers. These results focus on the need for guidelines to prevent cytotoxic vial contamination and safety recommendations for staff in the handling and storage of these vials.


Assuntos
Antineoplásicos , Exposição Ocupacional , Antineoplásicos/análise , Ciclofosfamida/análise , Citarabina , Contaminação de Medicamentos/prevenção & controle , Embalagem de Medicamentos , Monitoramento Ambiental/métodos , Humanos , Ifosfamida/análise , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/prevenção & controle , Plásticos
4.
Phys Med ; 85: 192-199, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34111631

RESUMO

PURPOSE: To compare patient radiation doses in cone beam computed tomography (CBCT) of two mobile systems used for navigation-assisted mini-invasive orthopedic surgery: O-arm®O2 and Surgivisio®. METHODS: The study focused on imaging of the spine. Thermoluminescent dosimeters were used to measure organs and effective doses (ED) during CBCT. An ionization-chamber and a solid-state sensor were used to measure the incident air-kerma (Ki) at the center of the CBCT field-of-view and Ki during 2D-imaging, respectively. The PCXMC software was used to calculate patient ED in 2D and CBCT configurations. The image quality in CBCT was evaluated with the CATPHAN phantom. RESULTS: The experimental ED estimate for the low-dose 3D-modes was 2.41 and 0.35 mSv with O-arm®O2 (Low Dose 3D-small-abdomen) and Surgivisio® (3DSU-91 images), respectively. PCXMC results were consistent: 1.54 and 0.30 mSv. Organ doses were 5 to 12 times lower with Surgivisio®. Ki at patient skin were comparable on lateral 2D-imaging (0.5 mGy), but lower with O-arm®O2 on anteroposterior (0.3 versus 0.9 mGy). Both systems show poor low contrast resolution and similar high contrast spatial resolution (7 line-pairs/cm). CONCLUSIONS: This study is the first to evaluate patient ED and organ doses with Surgivisio®. A significant difference in organs doses was observed between the CBCT systems. The study demonstrates that Surgivisio® used on spine delivers approximately five to six times less patient ED, compared to O-arm®O2, in low dose 3D-modes. Doses in 2D-mode preceding CBCT were higher with Surgivisio®, but negligible compared to CBCT doses under the experimental conditions tested.


Assuntos
Imageamento Tridimensional , Cirurgia Assistida por Computador , Tomografia Computadorizada de Feixe Cônico , Humanos , Imagens de Fantasmas , Doses de Radiação , Tomografia Computadorizada por Raios X
5.
Clin Case Rep ; 8(9): 1821-1823, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32983504

RESUMO

Hypersensitivity to etoposide phosphate has rarely been documented. We report a case of severe hypersensitivity reaction to etoposide phosphate in an old man. The patient experienced anaphylactic shock and has been hospitalized in intensive care unit. Vigilance is required regarding potential severe reactions with etoposide phosphate formulation.

6.
J Neurooncol ; 149(2): 193-208, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32809095

RESUMO

BACKGROUND: The purpose of this review is to summarize our own experimental studies carried out over a 13-year period of time using the F98 rat glioma as model for high grade gliomas. We evaluated a binary chemo-radiotherapeutic modality that combines either cisplatin (CDDP) or carboplatin, administered intracerebrally (i.c.) by means of convection-enhanced delivery (CED) or osmotic pumps, in combination with either synchrotron or conventional X-irradiation. METHODS: F98 glioma cells were implanted stereotactically into the brains of syngeneic Fischer rats. Approximately 14 days later, either CDDP or carboplatin was administered i.c. by CED, followed 24 h later by radiotherapy using either a synchrotron or, subsequently, megavoltage linear accelerators (LINAC). RESULTS: CDDP was administered at a dose of 3 µg in 5 µL, followed 24 h later with an irradiation dose of 15 Gy or carboplatin at a dose of 20 µg in 10 µL, followed 24 h later with 3 fractions of 8 Gy each, at the source at the European Synchrotron Radiation Facility (ESRF). This resulted in a median survival time (MeST) > 180 days with 33% long term survivors (LTS) for CDDP and a MeST > 60 days with 8 to 22% LTS, for carboplatin. Subsequently it became apparent that comparable survival data could be obtained with megavoltage X-irradiation using a LINAC source. The best survival data were obtained with a dose of 72 µg of carboplatin administered by means of Alzet® osmotic pumps over 7 days. This resulted in a MeST of > 180 days, with 55% LTS. Histopathologic examination of all the brains of the surviving rats revealed no residual tumor cells or evidence of significant radiation related effects. CONCLUSIONS: The results obtained using this combination therapy has, to the best of our knowledge, yielded the most promising survival data ever reported using the F98 glioma model.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Encefálicas/terapia , Quimiorradioterapia/métodos , Sistemas de Liberação de Medicamentos , Glioma/terapia , Animais , Neoplasias Encefálicas/patologia , Carboplatina/administração & dosagem , Cisplatino/administração & dosagem , Convecção , Glioma/patologia , Infusões Intralesionais , Ratos
8.
Eur Radiol ; 30(10): 5690-5701, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32361774

RESUMO

OBJECTIVES: To establish national reference levels (RLs) in interventional procedures under CT guidance as required by the 2013/59/Euratom European Directive. METHODS: Seventeen categories of interventional procedures in thoracic, abdominopelvic, and osteoarticular specialties (percutaneous infiltration, vertebroplasty, biopsy, drainage, tumor destruction) were analyzed. Total dose length product (DLP), number of helical acquisitions (NH), and total DLP for helical, sequential, or fluoroscopic acquisitions were recorded for 10 to 20 patients per procedure at each center. RLs were calculated as the 3rd quartiles of the distributions and target values for optimization process (TVOs) as the median. RLs and TVOs were compared with previously published studies. RESULTS: Results on 5001 procedures from 49 centers confirmed the great variability in patient dose for the same category of procedures. RLs were proposed for the DLPs and NHs in the seventeen categories. RLs in terms of DLP and NH were 375 mGy.cm and 2 NH for spinal or peri-spinal infiltration, 1630 mGy.cm and 3 NH for vertebroplasty, 845 mGy.cm and 4 NH for biopsy, 1950 mGy.cm and 8 NH for destruction of tumors, and 1090 mGy.cm and 5 NH for drainage. DLP and NH increased with the complexity of procedures. CONCLUSIONS: This study was the first nationwide multicentric survey to propose RLs for interventional procedures under CT guidance. Heterogeneity of practice in centers were found with different levels of patient doses for the same procedure. The proposed RLs will allow imaging departments to benchmark their practice with others and optimize their protocols. KEY POINTS: • National reference levels are proposed for 17 categories of interventional procedures under CT guidance. • Reference levels are useful for benchmarking practices and optimizing protocols. • Reference levels are proposed for dose length product and the number of helical acquisitions.


Assuntos
Doses de Radiação , Radiografia Intervencionista/normas , Valores de Referência , Tomografia Computadorizada por Raios X/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Feminino , Fluoroscopia/métodos , França , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Intervencionista/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Coluna Vertebral , Inquéritos e Questionários , Tomografia Computadorizada por Raios X/métodos , Vertebroplastia , Adulto Jovem
9.
J Exp Clin Cancer Res ; 31: 78, 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-22992374

RESUMO

BACKGROUND: The purpose of the present study was to compare side-by-side the therapeutic efficacy of a 6-day infusion of carboplatin, followed by X-irradiation with either 6 MV photons or synchrotron X-rays, tuned above the K-edge of Pt, for treatment of F98 glioma bearing rats. METHODS: Carboplatin was administered intracerebrally (i.c.) to F98 glioma bearing rats over 6 days using AlzetTM osmotic pumps starting 7 days after tumor implantation. Radiotherapy was delivered in a single 15 Gy fraction on day 14 using a conventional 6 MV linear accelerator (LINAC) or 78.8 keV synchrotron X-rays. RESULTS: Untreated control animals had a median survival time (MeST) of 33 days. Animals that received either carboplatin alone or irradiation alone with either 78.8 keV or 6 MV had a MeSTs 38 and 33 days, respectively. Animals that received carboplatin in combination with X-irradiation had a MeST of > 180 days with a 55% cure rate, irrespective of whether they were irradiated with either 78.8 KeV synchrotron X-rays or 6MV photons. CONCLUSIONS: These studies have conclusively demonstrated the equivalency of i.c. delivery of carboplatin in combination with X-irradiation with either 6 MV photons or synchrotron X-rays.


Assuntos
Neoplasias Encefálicas , Carboplatina/administração & dosagem , Glioma , Neoplasias Experimentais , Animais , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/radioterapia , Terapia Combinada , Glioma/tratamento farmacológico , Glioma/patologia , Glioma/radioterapia , Estimativa de Kaplan-Meier , Masculino , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Neoplasias Experimentais/radioterapia , Fótons , Ratos , Síncrotrons , Terapia por Raios X
10.
Appl Radiat Isot ; 69(12): 1813-6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21493080

RESUMO

In this report we have summarized our studies to optimize the delivery of boronophenylalanine (BPA) and sodium borocaptate (BSH) for boron neutron capture therapy (BNCT) of F98 glioma bearing rats. These results have been compared to a chemoradiotherapeutic approach using the same tumor model. The best survival data from our BNCT studies were obtained using a combination of BPA and sodium borocaptate BSH administered via the internal carotid artery, in combination with blood-brain barrier disruption (BBB-D). This treatment resulted in a mean survival time (MST) of 140 d with a 25% cure rate. The other approach combined intracerebral administration of carboplatin by either convection enhanced delivery (CED) or Alzet pump infusion, followed by external beam photon irradiation. This resulted in MSTs of 83 d and 112 d, respectively, with a cure rate of 40% for the latter. However, a significant problem that must be solved for both BNCT and this new chemoradiotherapeutic approach is how to improve drug uptake and microdistribution within the tumor.


Assuntos
Antineoplásicos/uso terapêutico , Terapia por Captura de Nêutron de Boro , Neoplasias Encefálicas/radioterapia , Carboplatina/uso terapêutico , Glioma/radioterapia , Animais , Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Carboplatina/administração & dosagem , Terapia Combinada , Glioma/tratamento farmacológico , Fótons , Ratos
11.
J Neurooncol ; 101(3): 379-90, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20577779

RESUMO

The purpose of this study was to further evaluate the therapeutic efficacy of convection enhanced delivery (CED) of carboplatin in combination with radiotherapy for treatment of the F98 rat glioma. Tumor cells were implanted stereotactically into the brains of syngeneic Fischer rats, and 13 or 17 d. later carboplatin (20 µg/10 µl) was administered by either CED over 30 min or by Alzet osmotic pumps (0.5 µg/µl/h for 168 h.) beginning at 7 d after tumor implantation. Rats were irradiated with a 15 Gy fractionated dose (5 Gy × 3) of 6 MV photons to the whole brain beginning on the day after drug administration. Other groups of rats received either carboplatin or X-irradiation alone. The tumor carboplatin concentration following CED of 20 µg in 10 µl was 10.4 µg/g, which was equal to that observed following i.v. administration of 100 mg/kg b.w. Rats bearing small tumors, treated with carboplatin and X-irradiation, had a mean survival time (MST) of 83.4 d following CED and 111.8 d following pump delivery with 40% of the latter surviving >180 d (i.e. cured) compared to 55.2 d for CED and 77.2 d. for pump delivery of carboplatin alone and 31.8 d and 24.2 d, respectively, for X-irradiated and untreated controls. There was no microscopic evidence of residual tumor in the brains of all long-term survivors. Not surprisingly, rats with large tumors had much shorter MSTs. Only modest increases in MSTs were observed in animals that received either oral administration or CED of temozolomide plus X-irradiation (23.2 d and 29.3 d) compared to X-irradiation alone. The present survival data, and those previously reported by us, are among the best ever obtained with the F98 glioma model. Initially, they could provide a platform for a Phase I clinical trial to evaluate the safety and potential therapeutic efficacy of CED of carboplatin in patients with recurrent glioblastomas, and ultimately a Phase II trial of carboplatin in combination with radiation therapy.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Carboplatina/administração & dosagem , Sistemas de Liberação de Medicamentos , Glioma/tratamento farmacológico , Glioma/radioterapia , Alquilantes/toxicidade , Animais , Neoplasias Encefálicas/induzido quimicamente , Neoplasias Encefálicas/patologia , Terapia Combinada , Convecção , Modelos Animais de Doenças , Etilnitrosoureia/toxicidade , Feminino , Glioma/induzido quimicamente , Glioma/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Doses de Radiação , Ratos , Ratos Endogâmicos F344 , Taxa de Sobrevida , Distribuição Tecidual , Terapia por Raios X
12.
J Neurooncol ; 98(3): 287-95, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20012464

RESUMO

We have evaluated the efficacy of intracerebral (i.c.) convection-enhanced delivery (CED) of cisplatin in combination with photon irradiation for the treatment of F98 glioma-bearing rats. One thousand glioma cells were stereotactically implanted into the brains of Fischer rats and 13 days later cisplatin (6 microg/20 microl) was administered i.c. by CED at a flow rate of 0.5 microl/min. On the following day the animals were irradiated with a single 15 Gy dose of X-rays, administered by a linear accelerator (LINAC) or 78.8 keV synchrotron X-rays at the European Synchrotron Radiation Facility (ESRF). Untreated controls had a mean survival time (MST) + or - standard error of 24 + or - 1 days compared to >59 + or - 13 days for rats that received cisplatin alone with 13% of the latter surviving >200 days. Rats that received cisplatin in combination with either 6 MV (LINAC) or 78.8 keV (synchrotron) X-rays had almost identical MSTs of >75 + or - 18 and >74 + or - 19 days, respectively with 17 and 18% long-term survivors. Microscopic examination of the brains of long-term surviving rats revealed an absence of viable tumor cells and cystic areas at the presumptive site of the tumor. Our data demonstrate that i.c. CED of cisplatin in combination with external X-irradiation significantly enhanced the survival of F98 glioma-bearing rats. This was independent of the X-ray beam energy and probably was not due to the production of Auger electrons as we previously had postulated. Our data provide strong support for the approach of concomitantly administering platinum-based chemotherapy in combination with radiotherapy for the treatment of brain tumors. Since a conventional LINAC can be used as the radiation source, this should significantly broaden the clinical applicability of this approach compared to synchrotron radiotherapy, which could only be carried out at a very small number of specialized facilities.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/terapia , Cisplatino/administração & dosagem , Glioma/tratamento farmacológico , Fótons/uso terapêutico , Radioterapia/métodos , Animais , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Terapia Combinada , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Sistemas de Liberação de Medicamentos/métodos , Glioma/mortalidade , Glioma/patologia , Masculino , Aceleradores de Partículas , Ratos , Ratos Endogâmicos F344 , Análise de Sobrevida , Síncrotrons
13.
J Synchrotron Radiat ; 16(Pt 4): 573-81, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19535873

RESUMO

Iodine-enhanced synchrotron stereotactic radiotherapy takes advantage of the radiation dose-enhancement produced by high-Z elements when irradiated with mono-energetic beams of synchrotron X-rays. In this study it has been investigated whether therapeutic efficacy could be improved using a thymidine analogue, 5-iodo-2'-deoxyuridine (IUdR), as a radiosentizing agent. IUdR was administered intracerebrally over six days to F98 glioma-bearing rats using Alzet osmotic pumps, beginning seven days after tumor implantation. On the 14th day, a single 15 Gy dose of 50 keV synchrotron X-rays was delivered to the brain. Animals were followed until the time of death and the primary endpoints of this study were the mean and median survival times. The median survival times for irradiation alone, chemotherapy alone or their combination were 44, 32 and 46 days, respectively, compared with 24 days for untreated controls. Each treatment alone significantly increased the rats' survival in comparison with the untreated group. Their combination did not, however, significantly improve survival compared with that of X-irradiation alone or chemotherapy alone. Further studies are required to understand why the combination of chemoradiotherapy was no more effective than X-irradiation alone.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Glioma/tratamento farmacológico , Glioma/radioterapia , Idoxuridina/administração & dosagem , Radiossensibilizantes/uso terapêutico , Animais , Terapia Combinada , Masculino , Ratos , Ratos Endogâmicos F344 , Síncrotrons , Raios X
14.
Int J Radiat Oncol Biol Phys ; 73(2): 530-6, 2009 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19147017

RESUMO

PURPOSE: To evaluate the efficacy of prolonged intracerebral (i.c.) administration of carboplatin by means of ALZET osmotic pumps, in combination with radiotherapy for the treatment of intracranial F98 glioma in rats. METHODS AND MATERIALS: Seven days after stereotactic implantation of F98 glioma cells into the brains of Fischer rats, carboplatin was administrated i.c. by means of ALZET pumps over 6 days. Rats were treated at the European Synchrotron Radiation Facility with a single 15-Gy X-ray dose, either given alone or 24 h after administration of carboplatin. RESULTS: Untreated rats had a mean survival time (MST) +/- SE of 23 +/- 1 days, compared with 44 +/- 3 days for X-irradiated animals and 69 +/- 20 days for rats that received carboplatin alone, with 3 of 13 of these surviving >195 days. Rats that received carboplatin followed by X-irradiation had a MST of >142 +/- 21 days and a median survival time of >195 days, with 6 of 11 rats (55%) still alive at the end of the study. The corresponding percentage increases in lifespan, based on median survival times, were 25%, 85%, and 713%, respectively, for carboplatin alone, radiotherapy alone, or the combination. CONCLUSIONS: Our data demonstrate that i.c. infusion of carboplatin by means of ALZET pumps in combination with X-irradiation is highly effective for the treatment of the F98 glioma. They provide strong support for the approach of concomitantly administering chemo- and radiotherapy for the treatment of brain tumors.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Carboplatina/administração & dosagem , Glioma/tratamento farmacológico , Glioma/radioterapia , Animais , Terapia Combinada/métodos , Bombas de Infusão , Masculino , Fótons/uso terapêutico , Distribuição Aleatória , Ratos , Ratos Endogâmicos F344 , Análise de Sobrevida
15.
Clin Cancer Res ; 13(17): 5195-201, 2007 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-17726137

RESUMO

PURPOSE: The goal of the present study was to evaluate the efficacy of intracerebral (i.c.) administration of carboplatin by means of convection-enhanced delivery (CED) in combination with fractionated, external beam photon irradiation for the treatment of F98 glioma-bearing rats. EXPERIMENTAL DESIGN: Carboplatin (20 microg/20 microL) was administrated i.c. by CED to F98 glioma-bearing rats, 13 days after stereotactic implantation of 10(3) tumor cells. One day following initiation of CED, a 24-Gy X-ray dose was administered in three daily fractions of 8 Gy each. Photon irradiation was carried out using either a conventional (6 MV) linear accelerator or a monochromatic synchrotron source (80 keV) at the European Synchrotron Radiation Facility. The primary end point of this study was overall survival. RESULTS: The median survival times were 79 and 60 days and the corresponding percent increase in life spans were 182% and 114%, respectively, for the combination of carboplatin chemotherapy and irradiation with either 6-MV or 80-keV photons. A subset of long-term survivors (>200 days) were observed in both chemoradiotherapy groups: 16.6% and 8.3% for 6 MV and 80 keV, respectively. In contrast, the median survival times for 6-MV or 80-keV irradiated controls, chemotherapy alone, and untreated controls were 42, 51, 45, and 28 days, respectively. CONCLUSIONS: Our results convincingly show the therapeutic efficacy of i.c. administration of carboplatin by means of CED in combination with either 6-MV or 80-keV photons. Further studies are warranted to optimize this combination of chemoradiotherapy for malignant gliomas.


Assuntos
Antineoplásicos/administração & dosagem , Carboplatina/administração & dosagem , Glioma/tratamento farmacológico , Fótons/uso terapêutico , Animais , Terapia Combinada , Glioma/mortalidade , Glioma/patologia , Humanos , Masculino , Ratos , Ratos Endogâmicos F344
16.
Int J Radiat Oncol Biol Phys ; 68(3): 943-51, 2007 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-17544004

RESUMO

PURPOSE: To evaluate direct intracerebral and intratumoral iodine delivery as means to improve iodine distribution for synchrotron stereotactic radiotherapy (SSR) and to evaluate the corresponding X-ray dose distribution. METHODS AND MATERIALS: Healthy rats and F98 glioma-bearing rats received an iodinated contrast agent (iopamidol) intracerebrally either by bolus injection (5 microL over approximately 1 min) or by convection-enhanced delivery (infusion volumes of 5, 10, and 20 microL at a rate of 0.5 microL/min). We used synchrotron computed tomography (CT) to determine the iodine distribution after completion of infusion and a Monte Carlo code to compute the resulting radiation dose in SSR. RESULTS: Post-infusion CT imaging revealed high iodine concentrations in the perfused area with both injection methods. The iodine concentration remained elevated, with an exponential decay time constant of approximately 50 min, well suited for SSR treatment. Convection-enhanced delivery was shown to provide more uniform and controlled volumes of distribution than bolus injection and was chosen to evaluate the corresponding X-ray dose distribution. Sharp dose gradients around the target and excellent sparing of the contralateral brain were achievable with low iodine concentrations in the surrounding healthy brain tissues and blood vessels. CONCLUSIONS: Convection-enhanced delivery is an effective method to deliver high iodine concentrations and could improve the outcome of iodine-enhanced SSR.


Assuntos
Neoplasias Encefálicas/radioterapia , Encéfalo/cirurgia , Glioma/radioterapia , Iopamidol/administração & dosagem , Radiocirurgia/métodos , Animais , Encéfalo/efeitos dos fármacos , Neoplasias Encefálicas/diagnóstico , Meios de Contraste/administração & dosagem , Glioma/diagnóstico , Injeções Intralesionais/métodos , Masculino , Radiometria/métodos , Dosagem Radioterapêutica , Ratos , Ratos Endogâmicos F344 , Síncrotrons
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