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1.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(5): 879-884, 2019 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-31631639

RESUMO

Radiotherapy is one of the main treatments for tumor with increasingly high request for technique precision and the equipment stability. Machine learning may bring radiotherapy simplicity, individualization and precision, and may improve the automatic level of planning and quality assurance. Based on the process of radiotherapy, this paper reviews the applications and researches on machine learning, with an emphasis on deep learning, and proposes the prospects in the following aspects: segmentation of normal tissue and tumor, planning, treatment delivery, quality assurance and prognosis prediction.


Assuntos
Aprendizado de Máquina , Neoplasias/radioterapia , Aprendizado Profundo , Humanos
2.
Ther Umsch ; 76(4): 209-218, 2019 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-31498043

RESUMO

Modern Treatment Concepts in Radiation Oncology Abstract. Radiotherapy is a widely used form of therapy that is used in half of all cancer patients. Advances in understanding the fundamentals of tumor and radiation biology, in medical physics and computer science as well as technical developments have continuously improved the effectiveness and healing success of radiotherapy. Patients benefit from new treatment concepts such as hypofractionated radiotherapy for breast and prostate cancer, leading to a reduction in the duration of treatment by several weeks. Selected patients with early stages of breast cancer can be treated with partial breast irradiation with focus on the tumor bed after breast conserving surgery increasing tolerability and comfort. High dose stereotactic radiotherapy over five to six sessions of radiation or only one fraction (radiosurgery) have expanded treatment options for common tumor entities leading to long-lasting tumor control resulting in improved survival and quality of life for those affected. In early lung cancer stereotactic radiotherapy is an alternative to primary tumor surgery. For patients with oligometastatic tumor disease stereotactic radiotherapy allows a curative approach by effectively treating metastases. In patients with brain metastases whole-brain irradiation is replaced by stereotactic irradiation of the individual metastases with fewer side effects. Recently, promising results for improved tumor control with the combination of radiotherapy and immunotherapy have been presented. Radioimmunotherapy represents a new therapy combination. However, final assessment of its efficacy and side effects profile is still missing. In order to gain therapeutic certainty, further prospective study data are necessary.


Assuntos
Neoplasias/radioterapia , Radioterapia (Especialidade) , Radiocirurgia , Humanos , Estudos Prospectivos , Qualidade de Vida
3.
Cancer Radiother ; 23(6-7): 496-499, 2019 Oct.
Artigo em Francês | MEDLINE | ID: mdl-31471251

RESUMO

Stereotactic radiotherapy of oligometastases, mono- or hypofractionated, represents a fundamental change in the practice of the specialty as it was developed for a century. Despite the great heterogeneity of sites, techniques, and doses, most studies found a high local control rate, around 70 to 90% at 2 years, and reduced toxicity, around 5% of grade 3 at 2 years. Four main phase II and III trials are underway in France. Future research concerns the association of stereotactic radiotherapy with immunotherapy or different conventional chemotherapy protocols, the identification of the best clinical presentations, and optimization of fractionation and biological dose for poor prognosis localizations.


Assuntos
Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Neoplasias/radioterapia , Radiocirurgia/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/secundário , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/radioterapia , Terapia Combinada/métodos , Previsões , França , Humanos , Imunoterapia , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/radioterapia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Masculino , Metástase Neoplásica , Neoplasias/patologia , Neoplasias/terapia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia
4.
Cancer Radiother ; 23(6-7): 581-591, 2019 Oct.
Artigo em Francês | MEDLINE | ID: mdl-31473088

RESUMO

Intensity modulated radiotherapy combined with image guided radiotherapy has led to increase the precision of external beam radiotherapy. However, intra or inter-fraction anatomical variations are frequent during the treatment course and can cause under-dosing of the target volume and/or over-dosing of the organs at risk. Several adaptive radiotherapy (ART) strategies can be defined to compensate these anatomical variations. The purpose of this article is to provide an overview of available ART strategies: offline, online, hybrid (library of treatment plans) or in real-time, while considering the arrival of MR-Linac devices in radiotherapy departments. The tools required to these ART strategies such as auto-segmentation, deformable image registration, calculation of the daily dose or dose accumulation, are also described. Implementing an ART strategy requires a rigorous quality assurance process, at each stage and on the entire workflow, as well as prior organization and training from of all the trades. A strong multidisciplinary involvement is finally required in order to ensure ART treatments.


Assuntos
Órgãos em Risco/efeitos da radiação , Garantia da Qualidade dos Cuidados de Saúde , Lesões por Radiação/prevenção & controle , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Radioterapia de Intensidade Modulada/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Neoplasias/radioterapia , Dosagem Radioterapêutica , Radioterapia de Alta Energia , Radioterapia Guiada por Imagem/instrumentação , Radioterapia de Intensidade Modulada/instrumentação
5.
Adv Exp Med Biol ; 1167: 225-236, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31520358

RESUMO

Ionizing radiation (IR) is used to treat more than half of human cancer patients. The therapeutic effect of IR is due to its ability to induce apoptosis. Success of radiation therapy relies not only on apoptosis induction but also on whether surviving cancer cells proliferate and regenerate a tumor. Drosophila melanogaster is a premier genetic model and, relevant to radiation biology of cancer, Drosophila larvae display an amazing capacity to regenerate. IR doses that kill more than half of the cells in larval tissues still allow complete regeneration to produce an adult fly of normal size and pattern. It is by understanding not only the initial effects of IR such as DNA damage and cell death but also longer-term regenerative responses that we may manipulate and improve radiation therapy of cancer. In this regard, Drosophila offers an unparalleled model to study both types of responses.


Assuntos
Drosophila melanogaster , Neoplasias/radioterapia , Animais , Apoptose , Modelos Animais de Doenças , Humanos , Radiação Ionizante , Radiobiologia
6.
Cancer Radiother ; 23(6-7): 617-624, 2019 Oct.
Artigo em Francês | MEDLINE | ID: mdl-31477441

RESUMO

Among over 100 proton therapy centres worldwide in operation or under construction, French proton therapy is coming to full maturity with the recent opening of the Nice (1991, upgrade in 2016) and Caen (2018) facilities next to the Orsay (1991, upgrade in 2010) centre. Proton therapy is a national priority for children and young adults in all three centres. The patient-related activity of the three French centres is coordinated via the Protonshare portal to optimise referral by type of indication and available expertise in coordination with the French society of radiation oncology SFRO and French radiotherapy centres. The centres are recognised by the French Health Care excellence initiative, promoted by the ministry of Foreign Affairs. The three centres collaborate structurally in terms of clinical research and are engaged at the international level in the participation to European databases and research initiatives. Concerted actions are now also promoted in preclinical research via the Radiotransnet network. Ongoing French developments in proton therapy are well presented in international hadron therapy meetings, including European Proton Therapy Network and Particle Therapy Cooperative Oncology Group. Proton therapy teaching in France is offered at several levels and is open to colleagues from all radiation oncology centres, so that they are fully informed, involved and trained to facility recognition of possible indications and thereby to contribute to appropriate patient referral. This close collaboration between all actors in French radiation oncology facilitates the work to demonstrate the required level of medical and scientific evidence for current and emerging indications for particle therapy. Based on that, the future might entail a possible creation of more proton therapy facilities in France.


Assuntos
Institutos de Câncer , Neoplasias/radioterapia , Terapia com Prótons , Radioterapia (Especialidade) , Adolescente , Adulto , Pesquisa Biomédica/organização & administração , Institutos de Câncer/organização & administração , Institutos de Câncer/provisão & distribução , Criança , Ciclotrons/provisão & distribução , Apoio Financeiro , França , Humanos , Cooperação Internacional , Terapia com Prótons/economia , Terapia com Prótons/instrumentação , Terapia com Prótons/métodos , Radioterapia (Especialidade)/educação , Radioterapia (Especialidade)/organização & administração , Adulto Jovem
7.
Cancer Radiother ; 23(6-7): 677-681, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31494038

RESUMO

In radiation therapy, a renewed interest is emerging for the study of spatially fractionated irradiation. In this article, a few applications using spatial fractionation of the dose will be discussed with a focus on proton minibeam radiation therapy. Examples of calculated dose (1D profiles and 2D dose distributions) and biological evidence obtained so far will be presented for various spatially fractionated techniques GRID, micro- and minibeam radiation therapy. Recent results demonstrating that proton minibeam radiation therapy leads to an increase in normal tissues sparing will be discussed, which opens the door to a dose escalation in the tumour and a possibly efficient treatment of very radioresistant tumours.


Assuntos
Fracionamento da Dose de Radiação , Neoplasias/radioterapia , Órgãos em Risco/efeitos da radiação , Terapia com Prótons/métodos , Animais , Humanos , Lesões por Radiação/prevenção & controle , Tolerância a Radiação , Ratos
8.
Gan To Kagaku Ryoho ; 46(8): 1219-1225, 2019 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-31501360

RESUMO

Although local tumor controls in various cancers by radiation therapy(RT)are dose dependent, dose-volume effects on late toxicities of surrounding normal tissues have been also observed. Particle beam therapy(PBT)using protons and carbonions have physical advantages in RT for the treatment of various cancers because they can create a desirable dose distribution to the target volume using fewer portals compared with photon-based RT. Thus, dose-escalation using charged particles is a reasonable approach in RT, theoretically. Based on accumulation of the evidences that PBT shows the efficacy in treatment for several cancers, the number of particle therapy facilities have been rapidly increasing worldwide. The Japanese Society for Radiation Oncology organized a joint effort among research groups to establish standardized treatment policies of particle therapy according to disease through systematic reviews. Furthermore, multicenter prospective studies have been conducted for hepatocellular carcinoma and prostate cancer. At the present, PBT for pediatric tumors, prostate cancer, unresectable bone and soft tissue sarcomas, head and neck non-squamous cell carcinomas is covered by the Japanese national health insurance system. Boron neutron capture therapy(BNCT)is also a promising modality as biochemically targeted RT, but it has been performed in only limited facilities. Recent advances in technology, accelerator-based neutron sources will increase in BNCT facilities and lead to wider application of BNCT for various cancers.


Assuntos
Terapia por Captura de Nêutron de Boro , Neoplasias/radioterapia , Humanos , Masculino , Estudos Prospectivos , Dosagem Radioterapêutica
9.
Anticancer Res ; 39(8): 4273-4277, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366517

RESUMO

BACKGROUND/AIM: For treatment of brain metastases, a patient's survival prognosis should be considered. Existing survival scores appear complex and require complete tumor staging. For many patients, a faster and simpler tool would be helpful. PATIENTS AND METHODS: This retrospective study investigated the prognostic value of the number of pre-treatment symptoms plus eight other factors on survival of patients irradiated for brain metastases. Other factors included whole-brain radiotherapy (WBRT) regimen, age, gender, performance score, primary tumor type, number of brain metastases, extracranial metastases, and interval between cancer diagnosis and WBRT. RESULTS: The number of symptoms (p=0.002) and all other factors were significantly associated with survival on univariate analyses. On multivariate analysis, all factors but the number of symptoms (p=0.47) and primary tumor type (p=0.48) were significant. CONCLUSION: Since the number of symptoms was not an independent predictor of survival, it cannot replace existing scoring tools and may only serve for orientation.


Assuntos
Neoplasias Encefálicas/radioterapia , Neoplasias/radioterapia , Prognóstico , Idoso , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Irradiação Craniana/efeitos adversos , Feminino , Humanos , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias/classificação , Neoplasias/patologia
10.
Life Sci ; 234: 116781, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31430455

RESUMO

Cancer stem cells (CSCs) are a population of self-renewal cells with high tumorigenic potency. CSCs can adopt easily with changes in the nearby milieu, and are more resistant to conventional therapies than other cells within a tumor. CSC resistance can be induced secondary to radio- and chemotherapy, or even after chemotherapy secession. A combination of both intrinsic and extrinsic factors is contributed to CSC-mediated therapy resistance. CSCs represent protective autophagy and efficient cell cycling, along with highly qualified epithelial-mesenchymal transition (EMT) regulators, reactive oxygen species (ROS) scavengers, drug transporters, and anti-apoptotic and DNA repairing systems. In addition, CSCs develop cross-talking and share some characteristics with other cells within the tumor microenvironment (TME) being more intense in higher stage tumors, and thereby sophisticating tumor-targeted therapies. TME, in fact, is a nest for aggravating resistance mechanisms in CSCs. TME is exposed constantly to the nutritional, metabolic and oxygen deprivation; these conditions promote CSC adaptation. This review is aimed to discuss main (intrinsic and extrinsic) mechanisms of CSC resistance and suggest some strategies to revoke this important promoter of therapy failure.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Células-Tronco Neoplásicas/patologia , Animais , Antineoplásicos/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos da radiação , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/efeitos da radiação , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos da radiação
11.
Cancer Radiother ; 23(6-7): 592-608, 2019 Oct.
Artigo em Francês | MEDLINE | ID: mdl-31427077

RESUMO

Adaptive radiotherapy (ART) is a complexe image-guided radiotherapy modality that comprises multiple planning to account for anatomical variations occurring during irradiation. Schematically, two strategies of RTA can be distinguished and combined according to tumor locations. One or more replanning can be proposed to correct systematic variations such as tumor shrinkage. A library of treatment plans with day-to-day plan selection from cone-beam CT imaging can also be proposed to correct random variations such as uterine motion or bladder/rectum volume changes. Because of strong anatomical variations occurring during irradiation, RTA appears therefore particularly justified in head and neck, lung, bladder, cervical and rectum and pancreas tumors, and to a lesser extent for prostate tumors and other digestive tumors. For these tumor locations, ART provides a fairly clear dosimetric benefit but a clinical benefit not yet formally demonstrated. ART cannot be proposed in a routine practice but must be evaluated medico-economically in the context of prospective trials. A rigorous quality control must be associated.


Assuntos
Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Radioterapia de Intensidade Modulada/métodos , Feminino , Neoplasias Gastrointestinais/radioterapia , Humanos , Neoplasias Pulmonares/radioterapia , Masculino , Neoplasias Otorrinolaringológicas/radioterapia , Neoplasias da Próstata/radioterapia , Neoplasias da Bexiga Urinária/radioterapia , Neoplasias do Colo do Útero/radioterapia
12.
Cancer Radiother ; 23(6-7): 609-616, 2019 Oct.
Artigo em Francês | MEDLINE | ID: mdl-31455590

RESUMO

The ambition of the RADIOTRANSNET network, launched by the INCa at the end of 2018, is to create a French research consortium dedicated to preclinical radiotherapy to foster scientific and clinical interactions at the interface of radiotherapy and radiobiology, and to identify research priorities dedicated to innovation in radiotherapy. The activities of the network are organized around four major axes that are target definition, normal tissue, combined treatments and dose modelling. Under the supervision of the Scientific Council, headed by a coordinator designated by the SFRO and a co-coordinator designated by the SFPM, three leaders coordinate each axis: a radiation-oncologist, a medical physicist and a biologist, who are responsible for organizing a scientific meeting based on the consensus conference methodology to identify priority issues. The selected themes will be the basis for the establishment of a strategic research agenda and a roadmap to help coordinate national basic and translational research efforts in oncological radiotherapy. This work will be published and will be transmitted to the funding institutions and bodies with the aim of opening dedicated calls to finance the necessary human and technical resources. Structuration of a preclinical research network will allow coordinating the efforts of all the actors in the field and thus promoting innovation in radiotherapy.


Assuntos
Pesquisa Biomédica/organização & administração , Neoplasias/radioterapia , Radioterapia (Especialidade)/organização & administração , Terapia Combinada , França , Física Sanitária , Humanos , Órgãos em Risco/efeitos da radiação , Radiobiologia , Dosagem Radioterapêutica
13.
Br J Radiol ; 92(1103): 20190180, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31437023

RESUMO

The aim of this article is to propose meaningful guidance covering the practical and technical issues involved when planning or conducting clinical trials involving positron emission tomography (PET)-guided radiotherapy. The complexity of imaging requirements will depend on the study aims, design and PET methods used. Where PET is used to adapt radiotherapy, a high level of accuracy and reproducibility is required to ensure effective and safe treatment delivery. The guidance in this document is intended to assist researchers designing clinical trials involving PET-guided radiotherapy to provide sufficient information about the appropriate methods to complete PET-CT imaging to a consistent standard at participating centres. The guidance is divided into six categories: application of PET in radiotherapy, resource requirements, quality assurance, imaging protocol design, data management and image processing. Each section provides an overview of the recent literature to support the specific recommendations. This guidance builds on previous recommendations from the National Cancer Research Institute PET Research Network and has been produced in collaboration with the National Radiotherapy Trials Quality Assurance Group.


Assuntos
Ensaios Clínicos como Assunto/métodos , Neoplasias/radioterapia , Tomografia por Emissão de Pósitrons/métodos , Protocolos Clínicos , Ensaios Clínicos como Assunto/normas , Fluordesoxiglucose F18 , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/normas , Garantia da Qualidade dos Cuidados de Saúde , Compostos Radiofarmacêuticos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Carga Tumoral
14.
Cancer Radiother ; 23(6-7): 753-760, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31427076

RESUMO

Imaging provides the basis for radiotherapy. Multi-modality images are used for target delineation (primary tumor and nodes, boost volume) and organs at risk, treatment guidance, outcome prediction, and treatment assessment. Next to anatomical information, more and more functional imaging is being used. The current paper provides a brief overview of the different applications of imaging techniques used in the radiotherapy process, focusing on uncertainties and QA. The paper mainly focuses on PET and MRI, but also provides a short discussion on DCE-CT. A close collaboration between radiology, nuclear medicine and radiotherapy departments provides the key to improve the quality of radiotherapy. Jointly developed imaging protocols (RT position setup, immobilization tools, lasers, flat table…), and QA programs are mandatory. For PET, suitable windowing in consultation with a Nuclear Medicine Physician is crucial (differentiation benign/malignant lesions, artifacts…). A basic knowledge of MRI sequences is required, in such a way that geometrical distortions are easily recognized by all members the RT and RT physics team. If this is not the case, then the radiologist should be introduced systematically in the delineation process and multidisciplinary meetings need to be organized regularly. For each image modality and each image registration process, the associated uncertainties need to be determined and integrated in the PTV margin. When using functional information for dose painting, response assessment or outcome prediction, collaboration between the different departments is even more important. Limitations of imaging based biomarkers (specificity, sensitivity) should be known.


Assuntos
Imagem por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Garantia da Qualidade dos Cuidados de Saúde , Planejamento da Radioterapia Assistida por Computador/métodos , Incerteza , Artefatos , Humanos , Imagem por Ressonância Magnética/normas , Imagem Multimodal/normas , Estadiamento de Neoplasias , Neoplasias/patologia , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/métodos , Tomografia por Emissão de Pósitrons/normas , Tomografia Computadorizada por Raios X/métodos
15.
Cancer Radiother ; 23(6-7): 745-752, 2019 Oct.
Artigo em Francês | MEDLINE | ID: mdl-31439430

RESUMO

PET/CT has become a standard examination in oncology but is probably still underused for radiotherapy planning. However, except for the clinical research data that shows the interest of this examination in considering personalized and adaptive radiotherapy, it is also important in defining target volumes. However, before using it in clinical practice, a few prerequisites are required to know the acquisition and segmentation methods. Ideally, PET/CT should become a standard examination for radiotherapy departments in the same way as planning CT and tomorrow as MRI.


Assuntos
Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Radio-Oncologistas , Planejamento da Radioterapia Assistida por Computador/métodos , Humanos , Seleção de Pacientes , Medicina de Precisão , Resultado do Tratamento
16.
Cancer Radiother ; 23(6-7): 625-629, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31447346

RESUMO

Recent technological developments in linear accelerators (linacs) and their imaging systems have made it possible to routinely perform stereotactic radiotherapy (SRT) treatments. To ensure the security and quality of the treatments, national and international recommendations have been written. This review focuses on the recommendations of the report 91 of the International Commission on Radiation Units (ICRU) on stereotactic treatments with small photon beams and proposes to answer the question of the eligibility of the commercially available accelerators for the treatment of extra-cranial SRT (SBRT). The ICRU 91 report outlines important features needed to respect the constraints, which are high intensity photon beam, integrated image-guidance, high mechanical accuracy of the linac, multileaf collimator with reduced leaf width, bundled motion management and bundled 6 Dimensional "robotic" couch tabletop. Most of the contemporary linacs meet these recommendations, in particular, stereotactic dedicated linacs, or modern gantry-based linacs equipped with 3 dimensional cone-beam CT imaging and 2D-stereoscopic planar imaging. Commercially available ring-based linacs have some limitations: they offer only coplanar treatments, and couch movements are limited to translations and, some have limited imaging equipment and no ability to manage intrafraction motion. However, for performing SBRT, non-coplanar irradiations are not mandatory, contrarily to intracranial stereotactic irradiations. Furthermore, patients' rotations can be corrected, thanks to real-time adaptive radiotherapy available on MRI-linacs. Finally, significant improvements are expected in the short term to compensate the weaknesses of the current devices.


Assuntos
Fidelidade a Diretrizes , Agências Internacionais/normas , Neoplasias/radioterapia , Aceleradores de Partículas/normas , Radiocirurgia/instrumentação , Desenho de Equipamento/normas , Humanos , Imobilização/instrumentação , Fótons/uso terapêutico , Garantia da Qualidade dos Cuidados de Saúde , Radiocirurgia/métodos , Radiocirurgia/normas , Radioterapia Guiada por Imagem/normas
17.
Cancer Radiother ; 23(6-7): 666-673, 2019 Oct.
Artigo em Francês | MEDLINE | ID: mdl-31451357

RESUMO

The impact of curative radiotherapy depends mainly on the total dose delivered homogenously in the target volume. Tumor sensitivity to radiotherapy may be particularly inconstant depending on location, histology, somatic genetic parameters and the capacity of the immune system to infiltrate the tumor. In addition, the dose delivered to the surrounding healthy tissues may reduce the therapeutic ratio of many radiation treatments. In a same population treated in one center with the same technique, it appears that individual radiosensitivity clearly exists, namely in terms of late side effects that are in principle non-reversible. This review details the different radiobiological approaches that have been developed to better predict the tumor response but also the radiation-induced late effects.


Assuntos
Neoplasias/radioterapia , Órgãos em Risco/efeitos da radiação , Tolerância a Radiação , Biomarcadores Tumorais , Células Sanguíneas/efeitos da radiação , Reparo do DNA/genética , Humanos , Neoplasias/genética , Especificidade de Órgãos , Prognóstico , Proteômica , Lesões por Radiação/etiologia , Dosagem Radioterapêutica , Sensibilidade e Especificidade , Resultado do Tratamento
18.
Cancer Radiother ; 23(5): 395-400, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31331842

RESUMO

PURPOSE: Lung and some digestive tumours move during a respiratory cycle. Four-dimensional scanography (4D-CT) is commonly used in treatment planning to account for respiratory motion. Although many French radiotherapy centres are now equipped, there are no guidelines on this subject to date. We wanted to draw up a description of the use of the 4D-CT for the treatment planning in France. METHODS AND MATERIAL: We conducted a survey in all French radiotherapy centres between March and April 2017. RESULTS: One hundred and seventy-two were contacted. The participation rate was 88.37%. The use of the 4D-CT seems to be common and concerned planning for 15.28% of kidney and adrenal cancers, 19.72% of pancreatic cancers, 27.78% of oesophageal cancers and 73.24% of lung cancers in case of normofractionated treatments. The use of the 4D-CT was also widespread in the case of stereotactic body radiation therapy: with 61.11% in the case of pulmonary irradiation and 34.72% in the case of hepatic irradiation. Many centres declared they carried out several 4D-CT for treatment planning (29, 55% in case of stereotactic body radiation therapy for lung tumours and 20% for liver tumours). Private centres tend to repeat 4D-CT more. CONCLUSION: Although the use of the 4D-CT appears to be developing, it remains very heterogeneous. To date, the repetition of the 4D-CT has been very poorly studied and could be the subject of clinical studies, allowing to define in which indications and for which populations there is a real benefit.


Assuntos
Tomografia Computadorizada Quadridimensional , Planejamento da Radioterapia Assistida por Computador/métodos , Artefatos , Institutos de Câncer/estatística & dados numéricos , França , Pesquisas sobre Serviços de Saúde , Hospitais Privados/estatística & dados numéricos , Hospitais Públicos/estatística & dados numéricos , Hospitais Universitários/estatística & dados numéricos , Humanos , Imagem Tridimensional/estatística & dados numéricos , Movimento (Física) , Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Utilização de Procedimentos e Técnicas , Serviço Hospitalar de Radiologia/estatística & dados numéricos , Radiocirurgia/métodos , Planejamento da Radioterapia Assistida por Computador/estatística & dados numéricos , Planejamento da Radioterapia Assistida por Computador/tendências , Respiração
19.
Gan To Kagaku Ryoho ; 46(5): 845-849, 2019 May.
Artigo em Japonês | MEDLINE | ID: mdl-31189801

RESUMO

The combination treatment of radiotherapy with anti-PD-1/PD-L1 antibody has been shown to significantly improve the clinical outcome of various cancers. Recent studies showthat radiotherapy has multiple functions in modifying the tumor microenvironment, by inducing both immunostimulation and immunosuppression. The upregulation of PD-L1 expression in cancer cells interferes with the effector functions of interacting T cells. Preclinical studies demonstrate that radiotherapy induces PD-L1 upregulation by 4 pathways; (1)IFN-γ signaling,(2)EGFR pathway,(3)DNA damage signaling pathway, and(4)cGAS-STING pathway. All of these mechanisms are involved in the upregulation of PD-L1 expression in cancer cells via JAK/STAT pathway. Because the PD-1/PD-L1 interaction has been shown to be one of the major mechanisms of cancer immune escape, which leads to treatment failure, anti-PD-1/PD-L1 antibody may improve the efficacy of radiotherapy by enhancement of anti-tumor activity. In addition, PD-L1 expression is one of the biomarkers of good response to anti-PD-1/ PD-L1 antibody. Therefore, the comprehensive understanding of the mechanism underlying PD-L1 expression in response to radiotherapy is important for the establishment of optimal combination strategy. This approach could help to provide the basis for the combined therapies and promote personalized immuno-radiotherapy, although the signaling of PD-L1 upregulation induced by radiotherapy in tumors could be intricately regulated. In this article, we review previous researches which revealed the mechanisms of PD-L1 upregulation induced by radiotherapy.


Assuntos
Neoplasias/radioterapia , Antígeno B7-H1 , Humanos , Interferon gama , Transdução de Sinais , Regulação para Cima
20.
Vet Clin North Am Small Anim Pract ; 49(5): 933-947, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31253427

RESUMO

Stereotactic radiotherapy (SRT) involves the precise delivery of highly conformal, dose-intense radiation to well-demarcated tumors. Special equipment and expertise are needed, and a unique biological mechanism distinguishes SRT from other forms of external beam radiotherapy. Families find the convenient schedules and minimal acute toxicity of SRT appealing. Common indications in veterinary oncology include nasal, brain, and bone tumors. Many other solid tumors can also be treated, including spinal, oral, lung, heart-base, liver, adrenal, and prostatic malignancies. Accessibility of SRT is improving, and new data are constantly emerging to define parameters for appropriate case selection, radiation dose prescription, and long-term follow-up."


Assuntos
Doenças do Gato/radioterapia , Doenças do Cão/radioterapia , Neoplasias/veterinária , Animais , Gatos , Cães , Oncologia , Neoplasias/radioterapia , Radioterapia (Especialidade)/métodos , Radiocirurgia/métodos , Radiocirurgia/veterinária , Radioterapia/métodos , Radioterapia/veterinária , Dosagem Radioterapêutica/veterinária , Medicina Veterinária
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