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[PMID]:29505510
[Au] Autor:Chen XR; Dong JN; Zhang F; Yao TL
[Ad] Endereço:Department of Ultrasound, The Second Affiliated Hospital of Mudanjiang Medical University.
[Ti] Título:Efficacy and safety of image-guidance radiotherapy by helical tomotherapy in patients with lung cancer.
[So] Source:Medicine (Baltimore);97(1):e9243, 2018 Jan.
[Is] ISSN:1536-5964
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:This study aimed to explore the efficacy and toxicity of image-guided stereotactic body radiotherapy (IGSBR) by helical tomotherapy in patients with lung cancer among Chinese Han population.A total of 21 patients with stage I lung cancer were included. They received a total of 60 Gy factions IGSBR. The outcomes included complete response (CR), partial response (PR), stable disease (SD), progress disease (PD), overall response rate (ORR), and overall survival (OS). In addition, toxicities were also recorded in this study.Three-year CR, PR, SD, PD, ORR, and OS were 47.6%, 38.1%, 9.5%, 4.8%, 85.7%, and 48.0 months, respectively. Additionally, mild toxicities were found in this study.This study demonstrated that IGSBR is efficacious for patients with stage I lung cancer with mild toxicities among Chinese Han population.
[Mh] Termos MeSH primário: Carcinoma/radioterapia
Neoplasias Pulmonares/radioterapia
[Mh] Termos MeSH secundário: Adulto
Idoso
Idoso de 80 Anos ou mais
Grupo com Ancestrais do Continente Asiático
Carcinoma Pulmonar de Células não Pequenas/radioterapia
Feminino
Seres Humanos
Masculino
Meia-Idade
Radioterapia Guiada por Imagem
Radioterapia de Intensidade Modulada
Estudos Retrospectivos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:180306
[St] Status:MEDLINE
[do] DOI:10.1097/MD.0000000000009243


  2 / 2104 MEDLINE  
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[PMID]:28749375
[Au] Autor:Kontaxis C; Bol GH; Stemkens B; Glitzner M; Prins FM; Kerkmeijer LGW; Lagendijk JJW; Raaymakers BW
[Ad] Endereço:Department of Radiotherapy, University Medical Center Utrecht, Heidelberglaan 100, Utrecht 3584 CX, The Netherlands.
[Ti] Título:Towards fast online intrafraction replanning for free-breathing stereotactic body radiation therapy with the MR-linac.
[So] Source:Phys Med Biol;62(18):7233-7248, 2017 Aug 21.
[Is] ISSN:1361-6560
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The hybrid MRI-radiotherapy machines, like the MR-linac (Elekta AB, Stockholm, Sweden) installed at the UMC Utrecht (Utrecht, The Netherlands), will be able to provide real-time patient imaging during treatment. In order to take advantage of the system's capabilities and enable online adaptive treatments, a new generation of software should be developed, ranging from motion estimation to treatment plan adaptation. In this work we present a proof of principle adaptive pipeline designed for high precision stereotactic body radiation therapy (SBRT) suitable for sites affected by respiratory motion, like renal cell carcinoma (RCC). We utilized our research MRL treatment planning system (MRLTP) to simulate a single fraction 25 Gy free-breathing SBRT treatment for RCC by performing inter-beam replanning for two patients and one volunteer. The simulated pipeline included a combination of (pre-beam) 4D-MRI and (online) 2D cine-MR acquisitions. The 4DMRI was used to generate the mid-position reference volume, while the cine-MRI, via an in-house motion model, provided three-dimensional (3D) deformable vector fields (DVFs) describing the anatomical changes during treatment. During the treatment fraction, at an inter-beam interval, the mid-position volume of the patient was updated and the delivered dose was accurately reconstructed on the underlying motion calculated by the model. Fast online replanning, targeting the latest anatomy and incorporating the previously delivered dose was then simulated with MRLTP. The adaptive treatment was compared to a conventional mid-position SBRT plan with a 3 mm planning target volume margin reconstructed on the same motion trace. We demonstrate that our system produced tighter dose distributions and thus spared the healthy tissue, while delivering more dose to the target. The pipeline was able to account for baseline variations/drifts that occurred during treatment ensuring target coverage at the end of the treatment fraction.
[Mh] Termos MeSH primário: Fracionamento de Dose
Imagem por Ressonância Magnética
Aceleradores de Partículas
Radiocirurgia/instrumentação
Planejamento da Radioterapia Assistida por Computador/métodos
Radioterapia Guiada por Imagem/instrumentação
[Mh] Termos MeSH secundário: Seres Humanos
Movimento
Respiração
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180302
[Lr] Data última revisão:
180302
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170728
[St] Status:MEDLINE
[do] DOI:10.1088/1361-6560/aa82ae


  3 / 2104 MEDLINE  
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[PMID]:28463166
[Au] Autor:Paul J; Yang C; Wu H; Tai A; Dalah E; Zheng C; Johnstone C; Kong FM; Gore E; Li XA
[Ad] Endereço:Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin.
[Ti] Título:Early Assessment of Treatment Responses During Radiation Therapy for Lung Cancer Using Quantitative Analysis of Daily Computed Tomography.
[So] Source:Int J Radiat Oncol Biol Phys;98(2):463-472, 2017 06 01.
[Is] ISSN:1879-355X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:PURPOSE: To investigate early tumor and normal tissue responses during the course of radiation therapy (RT) for lung cancer using quantitative analysis of daily computed tomography (CT) scans. METHODS AND MATERIALS: Daily diagnostic-quality CT scans acquired using CT-on-rails during CT-guided RT for 20 lung cancer patients were quantitatively analyzed. On each daily CT set, the contours of the gross tumor volume (GTV) and lungs were generated and the radiation dose delivered was reconstructed. The changes in CT image intensity (Hounsfield unit [HU]) features in the GTV and the multiple normal lung tissue shells around the GTV were extracted from the daily CT scans. The associations between the changes in the mean HUs, GTV, accumulated dose during RT delivery, and patient survival rate were analyzed. RESULTS: During the RT course, radiation can induce substantial changes in the HU histogram features on the daily CT scans, with reductions in the GTV mean HUs (dH) observed in the range of 11 to 48 HU (median 30). The dH is statistically related to the accumulated GTV dose (R > 0.99) and correlates weakly with the change in GTV (R = 0.3481). Statistically significant increases in patient survival rates (P=.038) were observed for patients with a higher dH in the GTV. In the normal lung, the 4 regions proximal to the GTV showed statistically significant (P<.001) HU reductions from the first to last fraction. CONCLUSION: Quantitative analysis of the daily CT scans indicated that the mean HUs in lung tumor and surrounding normal tissue were reduced during RT delivery. This reduction was observed in the early phase of the treatment, is patient specific, and correlated with the delivered dose. A larger HU reduction in the GTV correlated significantly with greater patient survival. The changes in daily CT features, such as the mean HU, can be used for early assessment of the radiation response during RT delivery for lung cancer.
[Mh] Termos MeSH primário: Tomografia Computadorizada Quadridimensional/normas
Neoplasias Pulmonares/diagnóstico por imagem
Neoplasias Pulmonares/radioterapia
Pulmão/efeitos da radiação
Radioterapia Guiada por Imagem/métodos
Carga Tumoral/efeitos da radiação
[Mh] Termos MeSH secundário: Adulto
Idoso
Idoso de 80 Anos ou mais
Feminino
Seres Humanos
Pulmão/diagnóstico por imagem
Neoplasias Pulmonares/mortalidade
Neoplasias Pulmonares/patologia
Masculino
Meia-Idade
Dosagem Radioterapêutica
Radioterapia Guiada por Imagem/normas
Taxa de Sobrevida
Fatores de Tempo
Resultado do Tratamento
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1707
[Cu] Atualização por classe:180228
[Lr] Data última revisão:
180228
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170503
[St] Status:MEDLINE


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[PMID]:29398305
[Au] Autor:Aghili M; Barzegartahamtan M; Alikhassi A; Mohammadpour R
[Ad] Endereço:Radiation Oncology Research Centre, Tehran University of Medical Sciences, Tehran, Iran.
[Ti] Título:Investigation of electron boost radiotherapy in patients with breast cancer: Is a direct electron field optimal?
[So] Source:Cancer Radiother;22(1):52-56, 2018 Feb.
[Is] ISSN:1769-6658
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:PURPOSE: Historically, electron boost dose mainly was delivered by a direct field in adjuvant radiotherapy of breast cancer. In this prospective study, we investigated direct electron field, in terms of optimal coverage of tumour bed volume following localization using ultrasound and surgical clips. MATERIAL AND METHODS: First, for all 24 patients, a breast sonographer drew perimeter of tumour bed on the breast skin. Then an electron boost field was outlined on the demarcated territory, and a lead wire marker compatible with CT scan was placed on the field borders by a 2cm margin. After CT scan simulation, all patients underwent adjuvant whole breast irradiation with 3D-conformal radiotherapy to 50Gy in 25 fractions. Then for boost radiotherapy, lead wire in CT images was countoured as electron boost field. Also, the tumour bed was contoured based on surgical clips (true clinical target volume and true planning target volume). Electron treatment planning was done for electron boost field. Finally isodose coverages for true planning target volume investigated. RESULTS: On average, 16.68% of clips planning target volume (true planning target volume; range: 0.00 to 95%) received 90% oor more of the prescribed dose when the electron treatment plan was made. Isodose curves does not provide adequate coverage on the tumour bed (clips planning target volume) when electron boost treatment planning was generated for electron boost field (en face electron field). In fact, a part of target (planning target volume-c) is missed and more doses is absorbed in normal tissue. CONCLUSIONS: Electron boost treatment planning (an en face electron field) following tumour bed localization using ultrasonography does not provide an optimized coverage of tumour bed volume.
[Mh] Termos MeSH primário: Neoplasias da Mama/radioterapia
Dosagem Radioterapêutica
Radioterapia Conformacional/métodos
[Mh] Termos MeSH secundário: Adulto
Idoso
Feminino
Seres Humanos
Imagem Tridimensional
Meia-Idade
Estudos Prospectivos
Radioterapia Adjuvante
Radioterapia Guiada por Imagem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180206
[St] Status:MEDLINE


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[PMID]:29276135
[Au] Autor:Barateau A; Céleste M; Lafond C; Henry O; Couespel S; Simon A; Acosta O; de Crevoisier R; Périchon N
[Ad] Endereço:Inserm U1099, campus de Beaulieu, 263, avenue du Général-Leclerc, 35000 Rennes, France; Laboratoire traitement du signal et de l'image (LTSI), université Rennes 1, campus de Beaulieu, 263, avenue du Général-Leclerc, CS 74205, 35042 Rennes cedex, France. Electronic address: a.barateau@rennes.unicance
[Ti] Título:[External beam radiotherapy cone beam-computed tomography-based dose calculation].
[Ti] Título:Calcul de dose de radiothérapie à partir de tomographies coniques : état de l'art..
[So] Source:Cancer Radiother;22(1):85-100, 2018 Feb.
[Is] ISSN:1769-6658
[Cp] País de publicação:France
[La] Idioma:fre
[Ab] Resumo:In external beam radiotherapy, the dose planning is currently based on computed tomography (CT) images. A relation between Hounsfield numbers and electron densities (or mass densities) is necessary for dose calculation taking heterogeneities into account. In image-guided radiotherapy process, the cone beam CT is classically used for tissue visualization and registration. Cone beam CT for dose calculation is also attractive in dose reporting/monitoring perspectives and particularly in a context of dose-guided adaptive radiotherapy. The accuracy of cone beam CT-based dose calculation is limited by image characteristics such as quality, Hounsfield numbers consistency and restrictive sizes of volume acquisition. The analysis of the literature identifies three kinds of strategies for cone beam CT-based dose calculation: establishment of Hounsfield numbers versus densities curves, density override to regions of interest, and deformable registration between CT and cone beam CT images. Literature results show that discrepancies between the reference CT-based dose calculation and the cone beam CT-based dose calculation are often lower than 3%, regardless of the method. However, they can also reach 10% with unsuitable method. Even if the accuracy of the cone beam CT-based dose calculation is independent of the method, some strategies are promising but need improvements in the automating process for a routine implementation.
[Mh] Termos MeSH primário: Tomografia Computadorizada de Feixe Cônico
Dosagem Radioterapêutica
Radioterapia Guiada por Imagem
[Mh] Termos MeSH secundário: Seres Humanos
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171226
[St] Status:MEDLINE


  6 / 2104 MEDLINE  
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[PMID]:29269165
[Au] Autor:Cao KI; Feuvret L; Herman P; Bolle S; Jouffroy T; Goudjil F; Amessis M; Rodriguez J; Dendale R; Calugaru V
[Ad] Endereço:Protontherapy Centre, institut Curie, 15, rue Georges-Clémenceau, 91400 Orsay, France; Department of Radiation Oncology, institut Curie, 26, rue d'Ulm, 75005 Paris, France. Electronic address: cao.kim@hotmail.fr.
[Ti] Título:Protontherapy of head and neck paragangliomas: A monocentric study.
[So] Source:Cancer Radiother;22(1):31-37, 2018 Feb.
[Is] ISSN:1769-6658
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:PURPOSE: The aim of this study was to assess efficacy and safety of proton beam therapy of paragangliomas of the head and neck, rare benign tumours developed close to crucial structures such as cranial nerves and vascular tissues. PATIENTS AND METHODS: Ten patients with a paraganglioma of the head and neck were treated from 2001 to 2014 with image-guided proton therapy. Neurological and ear nose throat symptoms were collected in addition to audiometric testing, before and after the treatment. Acute and late toxicities were assessed according to the Common Terminology Criteria for Adverse Events (CTCAE) v4. RESULTS: Median age at diagnosis was 52.6years (range: 18.2-65.8years). Proton therapy was the exclusive treatment in six patients and four patients had a postoperative radiotherapy. Median dose was 50.4Gy relative biological effectiveness (RBE; range: 45.0-67.0Gy). With a median follow-up of 24.6months (range: 6.7-46.2 months), local tumour control rate was 100% (stable, n=10). No upper grade 2 acute toxicity was reported. To the latest news, seven patients had controlled symptoms (improved, n=1, stabilized, n=6). One patient out of seven with initial tinnitus had a decrease in his symptoms, while the six other patients had a sustained stabilization. CONCLUSION: Proton beam therapy is an effective and well-tolerated treatment modality of skull base paragangliomas, with documented functional benefit. A longer follow-up is planned in order to assess local control and long-term toxicities.
[Mh] Termos MeSH primário: Neoplasias de Cabeça e Pescoço/radioterapia
Paraganglioma/radioterapia
Terapia com Prótons
Radioterapia Guiada por Imagem
[Mh] Termos MeSH secundário: Adolescente
Adulto
Idoso
Seguimentos
Seres Humanos
Meia-Idade
Qualidade de Vida
Estudos Retrospectivos
Zumbido/etiologia
Zumbido/terapia
Adulto Jovem
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171223
[St] Status:MEDLINE


  7 / 2104 MEDLINE  
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[PMID]:29221676
[Au] Autor:Lauche O; Castan F; de Forges H; Guillaumon C; Gourgou S; Fenoglietto P; Aillères N; Azria D; Riou O
[Ad] Endereço:Department of Radiation Oncology, institut régional du cancer de Montpellier (ICM), 208, avenue des Apothicaires, 34298 Montpellier, France. Electronic address: olivier.lauche@icm.unicancer.fr.
[Ti] Título:Prospective medical analysis of radiation therapist image repositioning during image-guided radiotherapy.
[So] Source:Cancer Radiother;22(1):25-30, 2018 Feb.
[Is] ISSN:1769-6658
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:PURPOSE: Radiation oncologists are responsible for deciding which day-to-day variations are acceptable or not in the treatment setup. However, properly qualified and trained radiation therapists might be capable to perform image registration. We evaluated in our centre the capability and accuracy of radiation therapists to validate positioning images in a prospective study. METHODS AND PATIENTS: A total of 84 patients treated for prostate, head and neck, lung or breast cancer was prospectively and randomly included from July 2011 to July 2013 in radiotherapy unit of our institution. For each patient, three positioning images were randomly analysed. Two radiation oncologists analysed all positioning images and shifts decided by the radiation therapists in an independent and blinded way. The radiation oncologists had to decide whether to validate or not this shift and give a corresponding additional shift, if any. A theoretical disagreement rate less than 5% between radiation therapists and radiation oncologists was planned. RESULTS: A total of 240 images were analysed (head and neck: 15.0%; prostate: 14.2%; breast: 55.0%; lung: 15.8%). The global disagreement between radiation oncologists and radiation therapists for all the images analysed was 2.5% 95% confidence interval (95% CI) [1.0-5.0], corresponding to six images out of 240. A 100% agreement was reached for prostate and lung images, a 97.2% agreement for head and neck images and a 96.2% agreement for breast images. CONCLUSIONS: The radiation therapist validation for repositioning images seemed accurate for image-guided radiotherapy in our institution. Periodic evaluation and in-house training are warranted when routine delegation of image registration to radiation therapists is considered.
[Mh] Termos MeSH primário: Pessoal Técnico de Saúde
Neoplasias/radioterapia
Variações Dependentes do Observador
Posicionamento do Paciente
Radio-Oncologistas
Radioterapia Guiada por Imagem
[Mh] Termos MeSH secundário: Feminino
França
Seres Humanos
Masculino
Estudos Prospectivos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180220
[Lr] Data última revisão:
180220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171210
[St] Status:MEDLINE


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[PMID]:29250970
[Au] Autor:Kliton J; Polgár C; Tenke P; Kovács G; Major T; Stelczer G; Ágoston P
[Ad] Endereço:Sugárterápiás Központ, Országos Onkológiai Intézet Budapest, Ráth Gy. u. 7-9., 1122.
[Ti] Título:[Image-guided radiotherapy for muscle invasive bladder cancer with intravesical lipiodol injection. A new option for bladder sparing treatment].
[Ti] Título:Izominvazív hólyagrák képvezérelt sugárkezelése intravesicalisan befecskendezett lipiodolos jelöléssel. A hólyagmegtartó kezelés új lehetosége..
[So] Source:Orv Hetil;158(51):2041-2047, 2017 Dec.
[Is] ISSN:0030-6002
[Cp] País de publicação:Hungary
[La] Idioma:hun
[Ab] Resumo:INTRODUCTION AND AIM: To implement lipiodol as a fiducial marker of the tumor bed for image-guided radiotherapy with simultaneous integrated boost technique as part of radiochemotherapy for muscle invasive bladder tumors. METHOD: Since April 2016, radiochemotherapy was performed in 3 male patients with muscle invasive, transitional cell bladder carcinoma. Prior to radiochemotherapy, tumor bed resection was performed for each patient, at the same time 10 ml of lipiodol solution was injected submucosally into the resection site, thus marking the tumor bed for escalated dose irradiation. During radiochemotherapy 51 Gy (1.7 Gy/die) to the pelvis, 57 Gy (1.9 Gy/die) to the whole bladder, and 63 Gy (2.1 Gy/die) to the lipiodol-labeled tumor bed was delivered with simultaneous integrated boost technique. The accuracy of the irradiation was controlled by daily kilovoltage CT. Early radiogenic urogenital and gastrointestinal side effects were recorded according to Radiation Therapy Oncology Group side-effects grading recommendation. RESULTS: Substantial perioperative side effect or toxicity were not observed during and after the injection of lipiodol. The prescribed dose was successfully delivered in all patients. Radiotherapy duration was 6 weeks. The lipiodol-labeled tumor bed was clearly visible on daily kilovoltage cone beam CT. In one patient grade II cystitis and proctitis was observed, another patient experienced only grade I cystitis. These complaints improved with symptomatic medication. In the third patient no significant side effect occurred. CONCLUSIONS: The injection of lipiodol into the bladder wall is a safe technique, without any perioperative toxicity or complication. The tumor bed demarcated by lipiodol was visible both on treatment planning and kilovoltage CTs. The total treatment time was shortened by 4 days. The treatment was well tolerated, early side effects were moderate, or slight. Orv Hetil. 2017; 158(51): 2041-2047.
[Mh] Termos MeSH primário: Meios de Contraste/administração & dosagem
Óleo Etiodado/administração & dosagem
Radioterapia Guiada por Imagem/métodos
Radioterapia de Intensidade Modulada/métodos
Neoplasias da Bexiga Urinária/radioterapia
[Mh] Termos MeSH secundário: Administração Intravesical
Quimiorradioterapia
Seres Humanos
Masculino
Procedimentos Cirúrgicos Urológicos/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Contrast Media); 8008-53-5 (Ethiodized Oil)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180215
[Lr] Data última revisão:
180215
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171219
[St] Status:MEDLINE
[do] DOI:10.1556/650.2017.30904


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[PMID]:28464742
[Au] Autor:Holm AIS; Petersen JBB; Muren LP; Seiersen K; Borghammer P; Lukacova S
[Ad] Endereço:a Department of Medical Physics , Aarhus University Hospital , Aarhus , Denmark.
[Ti] Título:Functional image-guided dose escalation in gliomas using of state-of-the-art photon vs. proton therapy.
[So] Source:Acta Oncol;56(6):826-831, 2017 Jun.
[Is] ISSN:1651-226X
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Recurrences of glioma are usually local, suggesting the need for higher tumor dose. We investigated the boundaries for dose escalation of an F-fluoro-ethyl-tyrosine positron emission tomography defined target by intensity-modulated photon therapy (IMRT), volumetric modulated arc therapy (VMAT) and intensity-modulated proton therapy (IMPT). MATERIALS AND METHODS: Standard dose (60 Gy) and dose-escalated plans were calculated for seven patients using IMRT, VMAT and IMPT. The achieved boost dose, the dose to the organs at risk (OAR), the dose homogeneity (defined as overdose volume, ODV) and the ratio of the 30 Gy isodose curve and the boost volume (R30) were compared. The risk of radionecrosis was estimated using the ratio of the dose volume histograms of the brain (range 30-60 Gy). RESULTS: The mean boost dose was 77.1 Gy for IMRT, 79.2 Gy for VMAT and 85.1 GyE for IMPT. Compared with the standard plan, the ODV was unchanged and the R30 increased (17%) for IMRT. For VMAT, the ODV decreased (7%) and the R30 was unchanged whereas IMPT substantially decreased ODV (61%), R30 (22%), OAR doses as well as the risk of radionecrosis. CONCLUSIONS: Dose escalation can be achieved with IMRT, VMAT and IMPT while respecting normal tissue constraints, yet with IMPT being most favorable.
[Mh] Termos MeSH primário: Neoplasias Encefálicas/radioterapia
Glioma/radioterapia
Recidiva Local de Neoplasia/radioterapia
Fótons/uso terapêutico
Terapia com Prótons
Planejamento da Radioterapia Assistida por Computador/métodos
Radioterapia Guiada por Imagem/métodos
[Mh] Termos MeSH secundário: Adulto
Idoso
Neoplasias Encefálicas/diagnóstico por imagem
Neoplasias Encefálicas/patologia
Feminino
Glioma/diagnóstico por imagem
Glioma/patologia
Seres Humanos
Processamento de Imagem Assistida por Computador/métodos
Masculino
Meia-Idade
Recidiva Local de Neoplasia/diagnóstico por imagem
Recidiva Local de Neoplasia/patologia
Órgãos em Risco/efeitos da radiação
Tomografia por Emissão de Pósitrons
Dosagem Radioterapêutica
Radioterapia de Intensidade Modulada/métodos
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180213
[Lr] Data última revisão:
180213
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE
[do] DOI:10.1080/0284186X.2017.1285498


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[PMID]:28464740
[Au] Autor:Lindblom E; Dasu A; Uhrdin J; Even A; van Elmpt W; Lambin P; Wersäll P; Toma-Dasu I
[Ad] Endereço:a Medical Radiation Physics, Department of Physics , Stockholm University , Stockholm , Sweden.
[Ti] Título:Defining the hypoxic target volume based on positron emission tomography for image guided radiotherapy - the influence of the choice of the reference region and conversion function.
[So] Source:Acta Oncol;56(6):819-825, 2017 Jun.
[Is] ISSN:1651-226X
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Hypoxia imaged by positron emission tomography (PET) is a potential target for optimization in radiotherapy. However, the implementation of this approach with respect to the conversion of intensities in the images into oxygenation and radiosensitivity maps is not straightforward. This study investigated the feasibility of applying two conversion approaches previously derived for F-labeled fluoromisonidazole ( F-FMISO)-PET images for the hypoxia tracer F-flortanidazole ( F-HX4). MATERIAL AND METHODS: Ten non-small-cell lung cancer patients imaged with F-HX4 before the start of radiotherapy were considered in this study. PET image uptake was normalized to a well-oxygenated reference region and subsequently linear and non-linear conversions were used to determine tissue oxygenations maps. These were subsequently used to delineate hypoxic volumes based partial oxygen pressure (pO ) thresholds. The results were compared to hypoxic volumes segmented using a tissue-to-background ratio of 1.4 for F-HX4 uptake. RESULTS: While the linear conversion function was not found to result in realistic oxygenation maps, the non-linear function resulted in reasonably sized sub-volumes in good agreement with uptake-based segmented volumes for a limited range of pO thresholds. However, the pO values corresponding to this range were significantly higher than what is normally considered as hypoxia. The similarity in size, shape, and relative location between uptake-based sub-volumes and volumes based on the conversion to pO suggests that the relationship between uptake and pO is similar for F-FMISO and F-HX4, but that the model parameters need to be adjusted for the latter. CONCLUSIONS: A non-linear conversion function between uptake and oxygen partial pressure for F-FMISO-PET could be applied to F-HX4 images to delineate hypoxic sub-volumes of similar size, shape, and relative location as based directly on the uptake. In order to apply the model for e.g., dose-painting, new parameters need to be derived for the accurate calculation of dose-modifying factors for this tracer.
[Mh] Termos MeSH primário: Aorta/patologia
Carcinoma Pulmonar de Células não Pequenas/patologia
Hipóxia/patologia
Neoplasias Pulmonares/patologia
Músculos/patologia
Tomografia por Emissão de Pósitrons/métodos
Radioterapia Guiada por Imagem/métodos
[Mh] Termos MeSH secundário: Aorta/diagnóstico por imagem
Aorta/efeitos da radiação
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem
Carcinoma Pulmonar de Células não Pequenas/radioterapia
Fluordesoxiglucose F18
Seres Humanos
Hipóxia/diagnóstico por imagem
Hipóxia/radioterapia
Neoplasias Pulmonares/diagnóstico por imagem
Neoplasias Pulmonares/radioterapia
Músculos/diagnóstico por imagem
Músculos/efeitos da radiação
Compostos Radiofarmacêuticos
Dosagem Radioterapêutica
Padrões de Referência
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Radiopharmaceuticals); 0Z5B2CJX4D (Fluorodeoxyglucose F18)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180213
[Lr] Data última revisão:
180213
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE
[do] DOI:10.1080/0284186X.2017.1293289



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