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1.
BMC Cancer ; 20(1): 702, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32727407

RESUMO

BACKGROUND: Craniospinal irradiation (CSI) of childhood tumors with the RapidArc technique is a new method of treatment. Our objective was to compare the acute hematological toxicity pattern during 3D conformal radiotherapy with the application of the novel technique. METHODS: Data from patients treated between 2007 and 2014 were collected, and seven patients were identified in both treatment groups. After establishing a general linear model, acute blood toxicity results were obtained using SPSS software. Furthermore, the exposure dose of the organs at risk was compared. Patients were followed for a minimum of 5 years, and progression-free survival and overall survival data were assessed. RESULTS: After assessment of the laboratory parameters in the two groups, it may be concluded that no significant differences were detected in terms of the mean dose exposures of the normal tissues or the acute hematological side effects during the IMRT/ARC and 3D conformal treatments. Laboratory parameters decreased significantly compared to the baseline values during the treatment weeks. Nevertheless, no significant differences were detected between the two groups. No remarkable differences were confirmed between the two groups regarding the five-year progression-free survival or overall survival, and no signs of serious organ toxicity due to irradiation were observed during the follow-up period in either of the groups. CONCLUSION: The RapidArc technique can be used safely even in the treatment of childhood tumors, as the extent of the exposure dose in normal tissues and the amount of acute hematological side effects are not higher with this technique.


Assuntos
Células Sanguíneas/efeitos da radiação , Neoplasias Encefálicas/radioterapia , Radiação Cranioespinal/métodos , Órgãos em Risco/efeitos da radiação , Radioterapia Conformacional/efeitos adversos , Adolescente , Adulto , Análise de Variância , Neoplasias Encefálicas/sangue , Criança , Pré-Escolar , Radiação Cranioespinal/efeitos adversos , Radiação Cranioespinal/mortalidade , Seguimentos , Humanos , Fígado/efeitos da radiação , Ossos Pélvicos/efeitos da radiação , Intervalo Livre de Progressão , Erros de Configuração em Radioterapia/prevenção & controle , Radioterapia Conformacional/métodos , Radioterapia Conformacional/mortalidade , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Radioterapia de Intensidade Modulada/mortalidade , Estudos Retrospectivos , Coluna Vertebral/efeitos da radiação , Baço/efeitos da radiação , Esterno/efeitos da radiação , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
2.
J Med Imaging Radiat Oncol ; 64(4): 580-585, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32588550

RESUMO

INTRODUCTION: Due to size and close proximity to skin, the sternum is a complicated target for stereotactic ablative body radiotherapy (SABR). This is a retrospective case series of single-fraction SABR to sternal metastasis in patients with oligometastatic breast cancer. METHODS: Between June 2014 and June 2018, ten breast cancer patients received 20 Gy in 1 fraction to a solitary sternal metastasis. Eligible patients had Eastern Cooperative Oncology Group performance status of 0-2, oligometastatic disease (defined as 1-5 metastases) and a controlled primary site. Patients were treated with 3-dimensional conformal radiotherapy, each patient case comprising of> 6 coplanar beams and 2-6 non-coplanar beams. Local control, pain response and adverse events were retrospectively reviewed. RESULTS: The median planned target volumes were 84.75cc (range, 14.4-197.8cc). The median conformity index was 1.29 (range, 1.2-1.49). At a median follow-up of 32 months, nine patients achieved in-field control. Two patients had triple negative disease, one of them developed marginal recurrence, and the other had in-field recurrence. Seven patients had sternal pain prior to SABR, and within 3 months after SABR treatment, the pain improved (n = 3) or resolved (n = 2). Four patients developed acute grade 1 and 2 skin reactions, and two patients had late grade 1 skin reactions. There were no grade 3 or 4 toxicities. CONCLUSION: Our case series demonstrates safety of SABR with associated disease control and analgesic benefit in selected patients with oligometastatic breast cancer. The marginal recurrence observed in this cohort suggests wider margins could be beneficial to account for microscopic disease.


Assuntos
Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Radiocirurgia/métodos , Esterno/efeitos da radiação , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Radioterapia Conformacional/métodos , Estudos Retrospectivos , Esterno/patologia , Resultado do Tratamento
3.
Lasers Med Sci ; 34(6): 1115-1124, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30547261

RESUMO

The aim of this study was to investigate the effects of low-level laser therapy (LLLT) versus trunk stabilization exercises on sternotomy healing following coronary artery bypass grafting (CABG) surgery. Forty-five male patients who had acute sternal instability post-CABG surgery in the age range of 45-65 years were divided randomly into three equal groups (n = 15). The laser group received LLLT, while the exercise group received trunk stabilization exercises. The control group only received a routine cardiac rehabilitation programme, which was also provided to both the laser and the exercise groups. All groups were offered 12 sessions over 4 weeks. Sternal separation, median sternotomy photographic analysis, pain and activities of daily living (ADL) performance were evaluated pre- and post-treatment. Statistical significance was set at P < 0.05. There was a significant decrease among the laser group in upper-sternal separation, while the exercise and control groups showed a non-significant decrease. In terms of mid-sternal separation, laser and exercise groups showed a significant decrease while the control group showed a non-significant decrease. In terms of lower-sternal separation, the exercise group showed a significant decrease, while the laser and control groups showed a non-significant decrease. Post-treatment between-groups analysis showed a significant difference only among the laser and control groups with regard to upper-sternal separation, while analysis of the laser, exercise and control groups in the case of upper-sternal separation and the between-groups comparison in terms of mid- and lower-sternal separation revealed no significant differences. LLLT and trunk stabilization exercises were found to be the most effective methods for sternotomy healing post-CABG surgery, with LLLT offering superior performance in the case of the upper sternum while trunk stabilization exercises were more effective for the lower sternum.


Assuntos
Ponte de Artéria Coronária , Terapia por Exercício , Terapia com Luz de Baixa Intensidade , Esternotomia , Tronco/efeitos da radiação , Cicatrização , Atividades Cotidianas , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modalidades de Fisioterapia , Esterno/efeitos da radiação , Esterno/cirurgia , Escala Visual Analógica
5.
Rofo ; 186(11): 1022-7, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24691839

RESUMO

PURPOSE: Although the use of thyroid shields for patients for head CT examinations is reasonable and even required by German regulations, so far available shields are often not used due to difficult applicability. New shields that are easier to use and therefore may gain wider acceptance and more frequent use are now available. In this work two new patient shields are investigated regarding their dose reduction effectiveness and applicability and compared to a thyroid/sternum shield typically used as a part of personal protective equipment. MATERIALS AND METHODS: The reduction of organ doses for thyroid, sternum and mamma were measured with thermoluminescence detectors in an anthropomorphic female phantom. Additionally, the influence of the length or position of the overview scan at the beginning of the CT examination was taken into account. RESULTS: Depending on the patient shield, a reduction of the organ doses for thyroid of 5 - 24 %, for sternum of 25 - 48 % and for mamma of 25 - 70 % could be found. A shift of 25 mm in the cranial direction for the overview scan resulted in a reduction of these organ doses of 12 - 15 %. CONCLUSION: Patient shields for cranial CT examinations provide a considerable dose reduction. New models are easily applied and no decrease in image quality through reconstruction artifacts could be found. Therefore, it is advised to use shields which are applied upon the patient without the need to be wrapped around the neck and the overview scan should be positioned as close as possible to the examined region. KEY POINTS: • New shields provide a compromise between usability and radiation protection.• Patient shields reduce organ doses even when not directly exposed.• The overview scan contributes considerably to out of field organ doses.• Shielding factors are greatly influenced by the positioning of the examination field.


Assuntos
Dispositivos de Proteção da Cabeça , Cabeça/diagnóstico por imagem , Proteção Radiológica/instrumentação , Ombro/efeitos da radiação , Esterno/efeitos da radiação , Tórax/efeitos da radiação , Glândula Tireoide/efeitos da radiação , Absorção de Radiação , Desenho de Equipamento , Feminino , Humanos , Imagens de Fantasmas , Doses de Radiação , Radiografia , Dosimetria Termoluminescente
6.
Thorac Cardiovasc Surg ; 62(1): 73-5, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22535672

RESUMO

High dose postmastectomy radiation therapy for breast cancer can lead to severe postirradiation sternal damage. Under these circumstances, median sternotomy may be associated with a prohibitive risk of postoperative deep sternal wound infection and alternative approaches have to be evaluated. We report herein the use of a right anterior minithoracotomy through the third intercostal space for isolated aortic valve replacement in one and combined aortic and mitral valve replacement in combination with mitral ring decalcification and coronary artery bypass grafting to the proximal right coronary artery in another patient.


Assuntos
Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca , Mastectomia , Valva Mitral/cirurgia , Lesões por Radiação/etiologia , Esterno/efeitos da radiação , Toracotomia/métodos , Idoso , Contraindicações , Ponte de Artéria Coronária , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Lesões por Radiação/diagnóstico , Radioterapia Adjuvante/efeitos adversos , Índice de Gravidade de Doença , Esternotomia , Esterno/diagnóstico por imagem , Esterno/patologia , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
7.
Ann Thorac Cardiovasc Surg ; 20 Suppl: 629-31, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23995346

RESUMO

A 79-year-old female patient was admitted because of profuse bleeding from a skin defect in the anterior chest due to a deep sternal wound infection. Eighteen years earlier, she had undergone irradiation to treat a sternal metastasis from breast cancer. Computed tomography (CT) showed the extravasation of iodinated contrast material from the ascending aorta. The patient underwent an immediate thoracotomy and recovered. This report presents a very rare case of massive bleeding from the thoracic aorta due to a mediastinal infection after irradiation for sternal metastasis from breast cancer.


Assuntos
Aorta Torácica/efeitos da radiação , Doenças da Aorta/etiologia , Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Hemorragia/etiologia , Mediastinite/etiologia , Osteomielite/etiologia , Lesões por Radiação/etiologia , Infecções Estafilocócicas/etiologia , Esterno/efeitos da radiação , Infecção dos Ferimentos/etiologia , Idoso , Aorta Torácica/diagnóstico por imagem , Doenças da Aorta/diagnóstico , Doenças da Aorta/terapia , Aortografia/métodos , Feminino , Hemorragia/diagnóstico , Hemorragia/terapia , Humanos , Mediastinite/diagnóstico , Mediastinite/terapia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Osteomielite/diagnóstico , Osteomielite/terapia , Lesões por Radiação/diagnóstico , Lesões por Radiação/terapia , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/terapia , Esterno/patologia , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Infecção dos Ferimentos/diagnóstico , Infecção dos Ferimentos/terapia
8.
Int J Radiat Oncol Biol Phys ; 79(2): 571-8, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-20950962

RESUMO

PURPOSE: A class of naturally occurring isoforms of tocopherol (tocols) was shown to have varying degrees of protection when administered before radiation exposure. We recently demonstrated that α-tocopherol succinate (TS) is a potential radiation prophylactic agent. Our objective in this study was to further investigate the mechanism of action of TS in mice exposed to (60)Co γ-radiation. METHODS AND MATERIALS: We evaluated the effects of TS on expression of antioxidant enzymes and oncogenes by quantitative RT-PCR in bone marrow cells of (60)Co γ-irradiated mice. Further, we tested the ability of TS to rescue and repopulate hematopoietic stem cells by analyzing bone marrow cellularity and spleen colony forming unit in spleen of TS-injected and irradiated mice. RESULTS: Our results demonstrate that TS modulated the expression of antioxidant enzymes and inhibited expression of oncogenes in irradiated mice at different time points. TS also increased colony forming unit-spleen numbers and bone marrow cellularity in irradiated mice. CONCLUSIONS: Results provide additional support for the observed radioprotective efficacy of TS and insight into mechanisms.


Assuntos
Antioxidantes/farmacologia , Células da Medula Óssea/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Protetores contra Radiação/farmacologia , alfa-Tocoferol/farmacologia , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Células da Medula Óssea/efeitos da radiação , Radioisótopos de Cobalto/farmacologia , Ensaio de Unidades Formadoras de Colônias/métodos , Primers do DNA/genética , Genes jun/efeitos dos fármacos , Genes jun/efeitos da radiação , Glutationa Peroxidase/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Glutationa Redutase/efeitos dos fármacos , Glutationa Redutase/metabolismo , Glutationa Transferase/efeitos dos fármacos , Glutationa Transferase/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/fisiologia , Células-Tronco Hematopoéticas/efeitos da radiação , Masculino , Camundongos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Baço/citologia , Baço/efeitos dos fármacos , Baço/efeitos da radiação , Esterno/citologia , Esterno/efeitos dos fármacos , Esterno/efeitos da radiação , Superóxido Dismutase/efeitos dos fármacos , Superóxido Dismutase/metabolismo
9.
Gen Thorac Cardiovasc Surg ; 58(12): 651-3, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21170638

RESUMO

Radiation-induced osteosarcoma is a rare complication after irradiation of primary malignancies. In the chest wall, it is usually secondary to radiotherapy for breast cancer or lymphoma. We report a rare case of radiation-induced osteosarcoma of the sternum after mediastinal irradiation of a thymoma. A 49-year-old woman presented with a sternal tumor 17 years after surgery plus mediastinal irradiation (50 Gy) for a stage III thymoma. On biopsy, this second tumor was diagnosed as a radiation-induced osteosarcoma. Systemic survey revealed additional metastatic spread to vertebrae and pelvis. Despite intensive combination chemotherapy that initially stabilized her disease, the patient died 2 years after the diagnosis was made. Because thymoma patients receiving mediastinal irradiation are thus at additional risk of radiation-induced secondary malignancy, long-term follow-up is advisable.


Assuntos
Neoplasias Ósseas/etiologia , Neoplasias Induzidas por Radiação/etiologia , Osteossarcoma/etiologia , Esterno/efeitos da radiação , Timectomia , Timoma/terapia , Neoplasias do Timo/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biópsia , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/patologia , Evolução Fatal , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/patologia , Osteossarcoma/tratamento farmacológico , Osteossarcoma/secundário , Radioterapia Adjuvante/efeitos adversos , Esterno/patologia , Timoma/radioterapia , Timoma/cirurgia , Neoplasias do Timo/radioterapia , Neoplasias do Timo/cirurgia , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
11.
Ann Thorac Surg ; 88(3): 987-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19699936

RESUMO

A 64-year-old man was referred for aortic valve replacement due to severe stenosis. He also suffered chronic sternal osteomyelitis with skin fistula subsequent to radiation therapy. Both pathologies were approached simultaneously by sternal resection, omental plasty, and valve replacement, which led to favorable primary and mid-term result.


Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica/efeitos da radiação , Implante de Prótese de Valva Cardíaca , Osteomielite/cirurgia , Lesões por Radiação/cirurgia , Infecções Estafilocócicas/cirurgia , Staphylococcus epidermidis , Esterno/efeitos da radiação , Esterno/cirurgia , Infecções Estreptocócicas/cirurgia , Estreptococos Viridans , Estenose da Valva Aórtica/diagnóstico por imagem , Doença Crônica , Terapia Combinada , Fístula Cutânea/diagnóstico por imagem , Fístula Cutânea/cirurgia , Fraturas Espontâneas/diagnóstico por imagem , Fraturas Espontâneas/cirurgia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Osteomielite/diagnóstico por imagem , Lesões por Radiação/diagnóstico por imagem , Radiodermatite/diagnóstico por imagem , Radiodermatite/cirurgia , Sarcoma/radioterapia , Infecções Estafilocócicas/diagnóstico por imagem , Esterno/diagnóstico por imagem , Esterno/lesões , Infecções Estreptocócicas/diagnóstico por imagem , Retalhos Cirúrgicos , Neoplasias Torácicas/radioterapia , Tomografia Computadorizada por Raios X
12.
Acta Orthop ; 79(4): 548-54, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18766490

RESUMO

BACKGROUND AND PURPOSE: There is increasing awareness that non-steroidal anti-inflammatory drugs (NSAIDs), and especially the cyclooxygenase-2 (COX-2) selective ones, may retard bone healing. We have used NSAIDs (indomethacin for at least 7 days) to prevent heterotopic ossification after acetabular reconstructions using impacted bone grafts. The long-term clinical results have been satisfying, making it difficult to believe that there is an important negative effect of NSAIDs on graft incorporation. We studied the effect of two different NSAIDs on bone and tissue ingrowth in a bone chamber model in goats, using autograft, rinsed allograft, and allograft that had been rinsed and subsequently irradiated. METHODS: 9 goats received no NSAIDs, 9 received ketoprofen, and 9 received meloxicam--all for 6 weeks. In each goat 6 bone chambers were implanted: 2 filled with autograft, 2 with rinsed allograft, and 2 with allograft that had been rinsed and irradiated. The amount of bone ingrowth and total tissue ingrowth was compared between the groups. RESULTS: There were no statistically significant differences in bone ingrowth between the different groups. Also, no differences in bone ingrowth were found with respect to the type of graft used. Furthermore, there was no statistically significant difference in the total amount of ingrowth of fibrous tissue between the treatment groups. INTERPRETATION: No differences in bone ingrowth in titanium bone chambers could be detected with both ketoprofen and meloxicam compared to untreated control animals. This confirms our hypothesis that the effect of NSAIDs on the incorporation and ingrowth of bone graft is limited.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Transplante Ósseo , Osso e Ossos/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/farmacologia , Cetoprofeno/farmacologia , Tiazinas/farmacologia , Tiazóis/farmacologia , Animais , Cultura em Câmaras de Difusão , Cabras , Humanos , Meloxicam , Osteogênese/efeitos dos fármacos , Esterno/efeitos dos fármacos , Esterno/efeitos da radiação , Esterno/transplante , Transplante Autólogo , Transplante Homólogo
13.
World J Surg Oncol ; 6: 138, 2008 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-19116008

RESUMO

BACKGROUND: Primary sternal malignant fibrous histiyocytoma (MFH) is highly rare. Effective treatment modality is surgical resection with wide margins. However, to date, the effects of radiotherapy or chemotherapy has not been clearly defined. CASE PRESENTATION: Herein, we aimed to present a 50-year old female patient with MFH occurred in the radiotherapy field who had had surgical procedure for breast cancer 19 years ago and had followed by radiotherapy. Neoadjuvant chemotherapy was applied for MFH due to cardiac and mediastinal vascular invasion. Wide resection was carried out for the mass after having been decreased in size following neoadjuvant chemotherapy. CONCLUSION: Neoadjuvant chemotherapy was an effective method. In planning the surgical resection, the size of the tumor before chemotherapy should be considered as the initial size and surgical margins should be determined accordingly.


Assuntos
Neoplasias Ósseas/terapia , Histiocitoma Fibroso Maligno/terapia , Radioterapia/efeitos adversos , Esterno/efeitos da radiação , Neoplasias da Mama/radioterapia , Quimioterapia Adjuvante , Terapia Combinada , Feminino , Histiocitoma Fibroso Maligno/patologia , Humanos , Pessoa de Meia-Idade
14.
Acta Orthop ; 78(1): 31-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17453390

RESUMO

BACKGROUND: Gamma irradiation has been widely used for sterilization of bone allografts. However, gamma irradiation alters proteins. This is favorable when it reduces immunogenicity, but is undesirable when osteoinductive proteins are damaged. Although the effect of gamma irradiation on BMPs has been studied, the effect of irradiation on the process of incorporation of morselized bone chips remains unclear. We studied the effects of sterilization by gamma irradiation on the incorporation of impacted morselized allografts. METHODS: Bone chambers with impacted allografts, rinsed impacted allografts, allografts that were rinsed and subsequently irradiated, and an empty control were implanted in proximal medial tibiae of goats. Incorporation was evaluated using histology and histomorphometry. RESULTS: Histology revealed evidence of bone graft incorporation, which proceeded in a similar way in unprocessed, rinsed, and both rinsed and irradiated bone grafts. After 12 weeks, no difference in bone and tissue ingrowth was found between the unprocessed, the rinsed, and the rinsed and subsequently irradiated allografts. The amount of unresorbed graft remnant was highest in the unprocessed bone grafts. INTERPRETATION: We conclude that sterilization with gamma irradiation does not influence the incorporation of impacted rinsed bone allografts.


Assuntos
Transplante Ósseo , Osso e Ossos/efeitos da radiação , Animais , Osso e Ossos/citologia , Cultura em Câmaras de Difusão , Feminino , Raios gama , Cabras , Humanos , Coloração e Rotulagem , Esterno/citologia , Esterno/efeitos da radiação , Esterno/transplante , Transplante Homólogo
15.
Clin Rheumatol ; 25(3): 409-11, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16220226

RESUMO

Bone pain due to bone metastases is a frequent presenting symptom of lung cancer. However, sternal metastases are unusual. We report two patients with inflammatory sternal metastases mimicking osteitis and indicating lung cancer. Chest computed tomography scan showed lytic lesion of the sternal manubrium invading anterior soft tissue. Diagnosis relied on histological examination of sternal biopsy and negative bacteriologic cultures. Local radiotherapy resulted in resolution of local signs.


Assuntos
Adenocarcinoma/secundário , Neoplasias Pulmonares/patologia , Metástase Neoplásica/patologia , Esterno/patologia , Neoplasias Torácicas/secundário , Adenocarcinoma/diagnóstico por imagem , Idoso , Diagnóstico Diferencial , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Osteíte/patologia , Radioterapia , Esterno/efeitos da radiação , Neoplasias Torácicas/diagnóstico por imagem , Neoplasias Torácicas/radioterapia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
16.
J Radiol ; 86(5 Pt 1): 487-91, 2005 May.
Artigo em Francês | MEDLINE | ID: mdl-16114205

RESUMO

PURPOSE: To estimate radiation doses from routine pediatric CT scans (body) and to propose dose reduction protocols. MATERIAL AND METHODS: [corrected] Study performed with a phantom equivalent to the body of 5 year old child with evaluation of doses delivered to breast, gonads, bone marrow (sternum, T12) and thyroid for CT examinations of the chest, abdomen, pelvis and spine. Extrapolation is made to estimate the doses for 1 year old and 10 year old children. Finally, dose reduction protocols are evaluated. RESULTS: CT of the chest delivers significant doses to breast tissue and bone marrow, CT of the abdomen and pelvis delivers significant doses to the ovaries and CT pf the spine delivers significant doses to thyroid and bone marrow. Optimization can be achieved without degradation of the image quality, by reducing Kv and mAs within reasonable limits. This study may be used in order to evaluate the doses delivered by multi-detector CT units.


Assuntos
Doses de Radiação , Efeitos da Radiação , Tomografia Computadorizada por Raios X , Medula Óssea/efeitos da radiação , Mama/efeitos da radiação , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Ovário/efeitos da radiação , Pelve/diagnóstico por imagem , Imagens de Fantasmas , Proteção Radiológica/métodos , Radiografia Abdominal , Radiografia Torácica , Coluna Vertebral/diagnóstico por imagem , Esterno/efeitos da radiação , Testículo/efeitos da radiação , Vértebras Torácicas/efeitos da radiação , Glândula Tireoide/efeitos da radiação
18.
Radiother Oncol ; 63(2): 217-22, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12063012

RESUMO

BACKGROUND AND PURPOSE: The purpose of this study was to perform in-vivo measurements of extracranial doses received by patients undergoing serial tomotherapy of the head and neck. MATERIAL AND METHODS: Intensity modulated radiotherapy treatment (IMRT) plans were designed for nine patients using the CORVUS treatment planning system (NOMOS Corp.). These plans were delivered using a tertiary collimator dedicated for serial tomotherapy attached to a 10-MV linear accelerator. For each patient, one optically stimulated luminescence dosimeter (OSLD) was placed on the sternum and one on the lower abdomen. The OSLDs were then processed, thereby estimating the in vivo absorbed doses to the sternum and gonads as a function of distance from the treatment site. RESULTS: The OSLDs were shown to measure known doses to within 5%, thereby validating their accuracy for this dose and energy range. In the patient studies, the dose received by the OSLDs varied in direct proportion to the number of monitor units delivered and inversely with the distance from the target volume; the patient dose at a distance of 15 cm from the target is approximately 0.4% of the total monitor units delivered, and drops to below 0.1% of the total MUs at approximately 40 cm from the center of the target. The average sternal dose was 1353 mSv and the average abdominal dose was 327 mSv for an average prescribed dose of 60.1 Gy. This can be attributed, at least partially, to the inefficient treatment delivery that on average required 9.9 MU/0.01 Gy. CONCLUSIONS: While IMRT reduces the normal tissue volume in the high-dose region, it also increases the overall monitor units delivered, and hence the whole-body dose, when compared with conventional treatment delivery. As has been noted in existing literature, these increases in whole-body dose from radiotherapy delivery may increase the likelihood of a radiation-induced secondary malignancy. Therefore, it is important to assess the risk of secondary malignancies from IMRT delivery, and compare this relative risk against the potential benefits of decreased normal tissue complication probabilities.


Assuntos
Gônadas/efeitos da radiação , Neoplasias de Cabeça e Pescoço/radioterapia , Radioterapia Assistida por Computador , Radioterapia de Alta Energia , Esterno/efeitos da radiação , Humanos , Aceleradores de Partículas , Doses de Radiação , Radiometria , Planejamento da Radioterapia Assistida por Computador
19.
Ann Thorac Cardiovasc Surg ; 7(6): 371-4, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11888478

RESUMO

A 59-year-old man who underwent radiation therapy (41 Gy) to the mediastinum through the anterior chest for Hodgkin's disease presented with a painful anterior chest wall tumor 18 years later. The tumor originated from the left parasternal region and was excised with the sternum. Chest wall reconstruction was performed. The tumor measured 45 x 45 mm and invaded the sternum. The pathologic diagnosis was malignant fibrous histiocytoma. Early and complete excision of the tumor is indicated.


Assuntos
Histiocitoma Fibroso Benigno/cirurgia , Neoplasias Induzidas por Radiação/cirurgia , Neoplasias Torácicas/cirurgia , Biópsia , Neoplasias Ósseas/patologia , Neoplasias Ósseas/cirurgia , Evolução Fatal , Histiocitoma Fibroso Benigno/patologia , Doença de Hodgkin/radioterapia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/patologia , Esterno/efeitos da radiação , Esterno/cirurgia , Neoplasias Torácicas/patologia , Tomografia Computadorizada por Raios X
20.
Med Dosim ; 24(2): 141-4, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10379512

RESUMO

The dose distributions for a patient with cancer involving the sternum were calculated for both a kilovoltage x-ray beam and a megavoltage electron beam. The minimum target dose and dose uniformity over the target volume were significantly better using electrons (90%-101%) than kilovoltage x-rays (68%-119%). The calculated lung dose and integral patient dose were also less for electrons than kilovoltage x-rays. For treating cancers of the sternum with radical intent, megavoltage electrons are recommended as the treatment mode of choice rather than kilovoltage x-rays.


Assuntos
Dosagem Radioterapêutica , Esterno/efeitos da radiação , Neoplasias Torácicas/radioterapia , Neoplasias da Mama/cirurgia , Elétrons , Feminino , Humanos , Pulmão/efeitos da radiação , Pessoa de Meia-Idade , Método de Monte Carlo , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Alta Energia , Espalhamento de Radiação , Neoplasias Torácicas/secundário , Raios X
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