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Targeting Tumor Perfusion and Oxygenation Modulates Hypoxia and Cancer Sensitivity to Radiotherapy and Systemic Therapies (Book chapter)

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ISBN: 9789533077031 Year: DOI: 10.5772/23332 Language: English
Publisher: IntechOpen Grant: FP7 Ideas: European Research Council - 243188
Subject: Science (General)
Added to DOAB on : 2019-01-17 11:47:59
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Hypoxia, a partial pressure of oxygen (pO2) below physiological needs, is a limiting factor affecting the efficiency of radiotherapy. Indeed, the reaction of reactive oxygen species (ROS, produced by water radiolysis) with DNA is readily reversible unless oxygen stabilizes the DNA lesion. While normal tissue oxygenation is around 40 mm Hg, both rodent and human tumors possess regions of tissue oxygenation below 10 mm Hg, at which tumor cells become increasingly resistant to radiation damage (radiobiological hypoxia) (Gray, 1953). Because of this so-called “oxygen enhancement effect”, the radiation dose required to achieve the same biologic effect is about three times higher in the absence of oxygen than in the presence of normal levels of oxygen (Gray et al., 1953; Horsman & van der Kogel, 2009). Hypoxic tumor cells, which are therefore more resistant to radiotherapy than well oxygenated ones, remain clonogenic and contribute to the therapeutic outcome of fractionated radiotherapy (Rojas et al., 1992).

Controversies and Perspectives in the Use of Postoperative Radiotherapy for Prostate Cancer

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889454501 Year: Pages: 74 DOI: 10.3389/978-2-88945-450-1 Language: English
Publisher: Frontiers Media SA
Subject: Medicine (General) --- Oncology
Added to DOAB on : 2018-11-16 17:17:57
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The use of radical prostatectomy in patients with high risk of recurrence has significantly increased during the past 10 years. Thus, adjuvant radiation as a part of multimodality treatment or salvage radiation at the evidence of prostate-specific antigen (PSA) progression represents mainstay curative-intent options for a great number of prostate cancer patients. Although, few randomized trials and many retrospective studies have been published, many uncertainties still mold the discussions on the best treatment management for men after prostatectomy. This research topic successfully intended to foster discussions on current controversies in the use of postoperative radiotherapy and to present novel perspectives for treatment optimization.

Image-Guided Radiotherapy for Effective Radiotherapy Delivery

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889198498 Year: Pages: 111 DOI: 10.3389/978-2-88919-849-8 Language: English
Publisher: Frontiers Media SA
Subject: Oncology --- Medicine (General)
Added to DOAB on : 2016-01-19 14:05:46
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Image-guided radiotherapy (IGRT) is a new radiotherapy technology that combines the rapid dose fall off associated with intensity-modulated radiotherapy (IMRT) and daily tumor imaging allowing for high precision tumor dose delivery and effective sparing of surrounding normal organs. The new radiation technology requires close collaboration between radiologists, nuclear medicine specialists, and radiation oncologists to avoid marginal miss. Modern diagnostic imaging such as positron emission tomography (PET) scans, positron emission tomography with Computed Tomograpgy (PET-CT), and magnetic resonance imaging (MRI) allows the radiation oncologist to target the positive tumor with high accuracy. As the tumor is well visualized during radiation treatment, the margins required to avoid geographic miss can be safely reduced , thus sparing the normal organs from excessive radiation. When the tumor is located close to critical radiosensitive structures such as the spinal cord, IGRT can deliver a high dose of radiation to the tumor and simultaneously decreasing treatment toxicity, thus potentially improving cure rates and patient quality of life. During radiotherapy, tumor shrinkage and changes of normal tissues/volumes can be detected daily with IGRT. The volume changes in the target volumes and organs at risk often lead to increased radiation dose to the normal tissues and if left uncorrected may result in late complications. Adaptive radiotherapy with re-planning during the course of radiotherapy is therefore another advantage of IGRT over the conventional radiotherapy techniques. This new technology of radiotherapy delivery provides the radiation oncologist an effective tool to improve patient quality of life. In the future, radiation dose-escalation to the residual tumor may potentially improve survival rates. Because the treatment complexity, a great deal of work is required from the dosimetry staff and physicists to ensure quality of care. Preliminary clinical results with IGRT are encouraging but more prospective studies should be performed in the future to assess the effectiveness of IGRT in improving patient quality of life and local control. In this Frontiers Research Topic, we encourage submission of original papers and reviews dealing with imaging for radiotherapy planning, the physics and dosimetry associated with IGRT, as well as the clinical outcomes for cancer treatment with IGRT for all tumor sites.

Global Challenges in Radiation Oncology

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Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889195909 Year: Pages: 66 DOI: 10.3389/978-2-88919-590-9 Language: English
Publisher: Frontiers Media SA
Subject: Oncology --- Medicine (General)
Added to DOAB on : 2016-03-10 08:14:32
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In the United States, much of the research is focused on developing new and very expensive technologies and drugs - often without a major therapeutic benefit. In resource limited countries, basic oncology care is frequently lacking. In addition, the benefits of various chemo-radiotherapy combinations for a number of malignancies are unknown as these populations have not been adequately investigated. For oncologists in these countries who have marginal to adequate resources, accrual to clinical trials is virtually non-existent to minimal, due to the complexities of their population and competing co-morbidities. As a result, there is a tremendous disparity in treatment outcomes for these populations, compared to those in developed countries. Therefore, we have asked a number of oncologists from different parts of the world to report their experience. Topics that will be covered include locally advanced breast and cervical cancer (India, South Africa), human resources for cancer control in India, systematic review of radiation resources in low and middle income countries, planning national radiotherapy services, building sustainable partnerships through the newly formed ICEC (International Cancer Export Corps), cancer disparities among American Indians, and training radiation oncologists in these under served parts of the world. Authors will discuss "lessons learned" from their populations, practical suggestions to address these disparities, and how we as a global oncology community can address, and mitigate these global challenges. The editorial by Dr. Coleman and myself highlights the invaluable contributions from our global contributors. Thank you for taking the time to read this special issue on global cancer disparities. We are all energized to begin addressing the needs of our cancer patients worldwide.

Charged Particles in Oncology

Authors: --- ---
Book Series: Frontiers Research Topics ISSN: 16648714 ISBN: 9782889453917 Year: Pages: 650 DOI: 10.3389/978-2-88945-391-7 Language: English
Publisher: Frontiers Media SA
Subject: Medicine (General) --- Oncology
Added to DOAB on : 2018-11-16 17:17:57
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High-energy charged particles represent a cutting-edge technique in radiation oncology. Protons and carbon ions are used in several centers all over the world for the treatment of different solid tumors. Typical indications are ocular malignancies, tumors of the base of the skull, hepatocellular carcinomas and various sarcomas. The physical characteristics of the charged particles (Bragg peak) allow sparing of much more normal tissues than it is possible using conventional X-rays, and for this reason all pediatric tumors are considered eligible for protontherapy. Ions heavier than protons also display special radiobiological characteristics, which make them effective against radioresistant and hypoxic tumors. On the other hand, protons and ions with high charge (Z) and energy (HZE particles) represent a major risk for human space exploration. The main late effect of radiation exposure is cancer induction, and at the moment the dose limits for astronauts are based on cancer mortality risk. The Mars Science Laboratory (MSL) measured the dose on the route to Mars and on the planet’s surface, suggesting that a human exploration missions will exceed the radiation risk limits. Notwithstanding many studies on carcinogenesis induced by protons and heavy ions, the risk uncertainty remains very high. In this research topic we aim at gathering the experiences and opinions of scientists dealing with high-energy charged particles either for cancer treatment or for space radiation protection. Clinical results with protons and heavy ions, as well as research in medical physics and pre-clinical radiobiology are reported. In addition, ground-based and spaceflight studies on the effects of space radiation are included in this book. Particularly relevant for space studies are the clinical results on normal tissue complications and second cancers. The eBook nicely demonstrates that particle therapy in oncology and protection of astronauts from space radiation share many common topics, and can learn from each other.

Pheochromocytoma (PHEO) and Paraganglioma (PGL)

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ISBN: 9783039216543 9783039216550 Year: Pages: 380 DOI: 10.3390/books978-3-03921-655-0 Language: English
Publisher: MDPI - Multidisciplinary Digital Publishing Institute
Subject: Medicine (General)
Added to DOAB on : 2019-12-09 11:49:16
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This book outlines some new advances in genetics, clinical evaluation, localization, therapy (newly including immunotherapy) of pheochromocytoma and paraganglioma including their metastatic counterparts. Well-known and experienced clinicians and scientists contributed to this book to include some novel approaches to these tumors. This book will serve to various health care professionals from different subspecialties, but mainly oncologists, endocrinologists, endocrine surgeons, pediatricians, and radiologists. This book shows that the field of pheochromocytoma/paraganglioma is evolving and a significant progress has been made in last 5 years requiring that health care professionals and scientists will learns new information and implement it in their clinical practice or scientific work, respectively. This book should not be missed by anybody who is focusing on neuroendocrine tumors, their newest evaluation and treatment.

Keywords

pheochromocytoma --- paraganglioma --- adrenocortical carcinoma --- adrenal tumor --- pan-cancer analysis --- neural crest --- neuroendocrine --- paraganglioma --- head and neck --- radiotherapy --- 18F-FDOPA --- PET --- GTV --- SDHB --- SDHD --- mortality --- paraganglioma --- pheochromocytoma --- radiofrequency ablation --- cryoablation --- percutaneous ethanol injection --- neuroendocrine tumor --- minimally invasive procedure --- percutaneous ablation --- PASS --- GAPP --- histology --- meta-analysis --- paraganglioma --- pheochromocytoma --- carotid body --- angiogenesis --- mitochondria --- neural crest --- neurogenesis --- paraganglioma --- stem-like tumor cells --- vasculogenesis --- xenograft --- pheochromocytoma --- catecholamine --- global longitudinal strain --- speckle-tracking echocardiography --- subclinical systolic dysfunction --- pheochromocytoma --- paraganglioma --- neuroendocrine tumor --- targeted therapy --- therapy resistance --- FGF21 --- pheochromocytoma --- paraganglioma --- diabetes mellitus --- obesity --- energy metabolism --- calorimetry --- chromogranin A --- metanephrines --- pheochromocytoma --- paraganglioma --- hypoxia --- pseudohypoxia --- spheroids --- HIF --- EPAS1 --- catecholamine --- pheochromocytoma and paraganglioma --- phosphorylation tyrosine hydroxylase --- dog --- pheochromocytoma --- paraganglioma --- SDHB --- SDHD --- mutation --- chromosomal alteration --- comparative genomics --- pheochromocytoma --- paraganglioma --- metastatic --- immunotherapy --- innate immunity --- adaptive immunity --- toll-like receptor --- pathogen-associated molecular patterns --- neutrophil --- T cell --- pheochromocytoma --- paraganglioma --- hypertension --- blood pressure variability --- average real variability --- weighted standard deviation --- paraganglioma --- somatostatinoma --- polycythemia --- EPAS1 --- transgenic mice --- erythropoietin --- pheochromocytoma --- paraganglioma --- TCA cycle --- germline mutation --- metastatic OR malignant pheochromocytoma --- paraganglioma --- ectopic secretion --- lL-6 --- normetanephrines --- VHL --- NF1 --- EPAS1 --- hypoxia-inducible factor --- inflammation --- radiosensitization --- succinate dehydrogenase --- mouse pheochromocytoma cells --- immunohistochemistry --- fluorescence imaging --- pheochromocytoma --- paraganglioma --- next-generation sequencing --- sporadic --- hereditary --- CNV detection --- pheochromocytoma --- paraganglioma --- PET-CT --- 11C-hydroxy-ephedrine --- adrenal incidentaloma --- pheochromocytoma --- paraganglioma --- 177Lu-DOTATATE --- peptide receptor radiotherapy --- PRRT --- neuroendocrine tumor --- NET --- PCC --- PGL --- postoperative --- pheochromocytoma --- hypertension --- hypotension --- arrhythmia --- PPGL --- catecholamines --- adrenomedullary function --- n/a

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