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Yap ML, O'Connell DL, Goldsbury D, Weber M, Barton M. Comparison of four methods for estimating actual radiotherapy utilisation using the 45 and Up Study cohort in New South Wales, Australia. Radiother Oncol 2019; 131:14-20. [DOI: 10.1016/j.radonc.2018.10.039] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 09/15/2018] [Accepted: 10/14/2018] [Indexed: 10/27/2022]
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Broekhuis F, O'Meara RH, O'Meara S, Barton M, Harrell C, Western G, Elliot NB. An assessment of mammals in Naimina Enkiyio Forest, Kenya. Afr J Ecol 2018. [DOI: 10.1111/aje.12532] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Gibbons J, Barton M, Brault E. Evaluating gentrification's relation to neighborhood and city health. PLoS One 2018; 13:e0207432. [PMID: 30452460 PMCID: PMC6242354 DOI: 10.1371/journal.pone.0207432] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Accepted: 10/31/2018] [Indexed: 11/25/2022] Open
Abstract
Gentrification has been argued to contribute to urban inequalities, including those of health disparities. Extant research has yet to conduct a systematic study of gentrification's relation with neighborhood health outcomes nationally. This gap is addressed in the current study through the utilization of census-tract data from the Center for Disease Control's 500 Cities project, the 2000 Census and the 2010-2014 American Community Survey to examine how gentrification relates to local self-rated physical health in select cities across the United States. We examine gentrification's association with neighborhood rates of poor self-rated physical health. We contextualize this relationship by evaluating gentrification's relation with city-level self-rated health inequalities. We find gentrification was significantly and positively related with self-rated physical neighborhood health outcomes. However, the presence and magnitude of gentrification within a city was not associated with health outcomes for cities overall. Based on these findings, we argue that gentrification's health benefits for cities are limited at best, though gentrification does not appear to be associated with deepening city-level health inequalities, either.
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Barton M. What do undergraduate doctors really need to know about radiation oncology? J Med Imaging Radiat Oncol 2018; 62:823-825. [PMID: 30417554 DOI: 10.1111/1754-9485.12834] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Accepted: 10/17/2018] [Indexed: 11/28/2022]
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Batumalai V, Shafiq J, Gabriel G, Hanna TP, Delaney GP, Barton M. Impact of radiotherapy underutilisation measured by survival shortfall, years of potential life lost and disability-adjusted life years lost in New South Wales, Australia. Radiother Oncol 2018; 129:191-195. [DOI: 10.1016/j.radonc.2018.06.026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 05/23/2018] [Accepted: 06/21/2018] [Indexed: 10/28/2022]
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Do V, Ng W, Jacob S, Delaney G, Barton M. An estimation of the population-based survival benefit of first-course chemotherapy for advanced incurable cancer. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy440.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Liney G, Whelan B, Oborn B, Barton M, Keall P. MRI-Linear Accelerator Radiotherapy Systems. Clin Oncol (R Coll Radiol) 2018; 30:686-691. [DOI: 10.1016/j.clon.2018.08.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 07/25/2018] [Accepted: 08/20/2018] [Indexed: 12/25/2022]
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Yam C, Seth S, Hess K, Mittendorf E, Murthy R, Damodaran S, Helgason T, Huo L, Thompson A, Barton M, Huang M, Arribas E, Lane D, Rauch G, Adrada B, Gilcrease M, Chang J, Moulder S. Impact of clinical, morphologic and molecular characteristics on response to neoadjuvant systemic therapy (NAST) in metaplastic breast cancer (MpBC). Ann Oncol 2018. [DOI: 10.1093/annonc/mdy270.223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Barton M, Little HJ, Vaughan-Jones RD, Daniels S, Dashwood MR, Tsui JC. Sidney George Shaw, DPhil (1948-2017). Physiol Res 2018; 67:S27-S35. [PMID: 31774298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023] Open
Abstract
On March 4, 2017 at the age of 68, Sidney George Shaw (Sid) unexpectedly died from complications following surgery, only four years after retiring from the University of Bern. Trained in biochemistry at Oxford University, Sid had quickly moved into molecular pharmacology and became a key investigator in the field of enzyme biochemistry, vasoactive peptide research, and receptor signaling. Sid spent half his life in Switzerland, after moving to the University of Bern in 1984. This article, written by his friends and colleagues who knew him and worked with him during different stages of his career, summarizes his life, his passions, and his achievements in biomedical research. It also includes personal memories relating to a dear friend and outstanding scientist whose intellectual curiosity, humility, and honesty will remain an example to us all.
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Liney GP, Dong B, Weber E, Rai R, Destruel A, Garcia-Alvarez R, Manton DJ, Jelen U, Zhang K, Barton M, Keall P, Crozier S. Imaging performance of a dedicated radiation transparent RF coil on a 1.0 Tesla inline MRI-linac. ACTA ACUST UNITED AC 2018; 63:135005. [DOI: 10.1088/1361-6560/aac813] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Yao R, Murtaza M, Velasquez JT, Todorovic M, Rayfield A, Ekberg J, Barton M, St John J. Olfactory Ensheathing Cells for Spinal Cord Injury: Sniffing Out the Issues. Cell Transplant 2018; 27:879-889. [PMID: 29882418 PMCID: PMC6050914 DOI: 10.1177/0963689718779353] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Olfactory ensheathing cells (OECs) are glia reported to sustain the continuous axon extension and successful topographic targeting of the olfactory receptor neurons responsible for the sense of smell (olfaction). Due to this distinctive property, OECs have been trialed in human cell transplant therapies to assist in the repair of central nervous system injuries, particularly those of the spinal cord. Though many studies have reported neurological improvement, the therapy remains inconsistent and requires further improvement. Much of this variability stems from differing olfactory cell populations prior to transplantation into the injury site. While some studies have used purified cells, others have used unpurified transplants. Although both preparations have merits and faults, the latter increases the variability between transplants received by recipients. Without a robust purification procedure in OEC transplantation therapies, the full potential of OECs for spinal cord injury may not be realised.
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Rosenblatt E, Fidarova E, Ghosh S, Zubizarreta E, Unterkirhere O, Semikoz N, Sinaika V, Kim V, Karamyan N, Isayev I, Akbarov K, Lomidze D, Bondareva O, Tuzlucov P, Zardodkhonova M, Tkachev S, Kislyakova M, Alimov J, Pidlubna T, Barton M, Mackillop W. Quality of radiotherapy services in post-Soviet countries: An IAEA survey. Radiother Oncol 2018; 127:171-177. [PMID: 29705501 DOI: 10.1016/j.radonc.2018.03.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 03/18/2018] [Accepted: 03/28/2018] [Indexed: 10/17/2022]
Abstract
BACKGROUND The quality of radiotherapy services in post-Soviet countries has not yet been studied following a formal methodology. The IAEA conducted a survey using two sets of validated radiation oncology quality indicators (ROIs). METHODS Eleven post-Soviet countries were assessed. A coordinator was designated for each country and acted as the liaison between the country and the IAEA. The methodology was a one-time cross-sectional survey using a 58-question tool in Russian. The questionnaire was based on two validated sets of ROIs: for radiotherapy centres, the indicators proposed by Cionini et al., and for data at the country level, the Australasian ROIs. RESULTS The overall response ratio was 66.3%, but for the Russian Federation, it was 24%. Data were updated on radiotherapy infrastructure and equipment. 256 radiotherapy centres are operating 275 linear accelerators and 337 Cobalt-60 units. 61% of teletherapy machines are older than ten years. Analysis of ROIs revealed significant differences between these countries and radiotherapy practices in the West. Naming, task profile and education programmes of radiotherapy professionals are different than in the West. CONCLUSIONS Most countries need modernization of their radiotherapy infrastructure coupled with adequate staffing numbers and updated education programmes focusing on evidence-based medicine, quality, and safety.
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Pham T, Stait-Gardner T, Lee C, Barton M, Liney G, Wong K, Price W. PO-0979: Ultra-high field MRI for evaluation of rectal cancer stroma ex vivo: correlation with histopathology. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)31289-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Whelan B, Welgampola M, McGarvie L, Makhija K, Turner RM, Holloway L, Feain I, Jackson M, Barton M, Keall P. Patient reported outcomes of slow, single arc rotation: Do we need rotating gantries? J Med Imaging Radiat Oncol 2017; 62:553-561. [PMID: 29139207 DOI: 10.1111/1754-9485.12688] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 10/03/2017] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Patient rotation could greatly simplify radiation therapy delivery, with particularly important ramifications for fixed beam treatment with protons, heavy ions, MRI-Linacs, and low cost Linacs. Patient tolerance is often cited as a barrier to widespread implementation to patient rotation; however, no quantitative data addressing this issue exists. In this study, patient reported experiences of slow, single arc rotation in upright (sitting) and lying orientations are reported. METHODS Fifteen patients currently or previously treated for cancer were slowly (~2 rpm) rotated in upright and lying orientations using an existing medical device. Patients were rotated 360° in 45° increments. Rotation was paused for 30 seconds at each angle to simulate beam delivery. Claustrophobia, anxiety and motion sickness were monitored via validated questionnaires. The Wilcoxon signed rank test was used to test for significant differences in anxiety and motion sickness before, during and after the study. RESULTS No significant differences in anxiety or motion sickness were found between before and after the study, or upright and lying rotation (P > 0.05). The median percentage scores for anxiety and motion sickness immediately following the study were both 0. In general, anxiety and motion sickness scores were low throughout the study. All patients except one completed the study. CONCLUSIONS Slow, single arc rotation in upright and lying orientations was well tolerated in this study. These results support the need for further studies into the clinical implementation of patient rotation, which could have a major impact on the practice and cost of radiotherapy.
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Logeman CJ, Flanigan J, Foliaki S, Bray F, Barton M, Sitas F. Cancer in small states - No small matter. Cancer Epidemiol 2017; 50:173-175. [PMID: 29120822 DOI: 10.1016/j.canep.2017.09.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Do V, Ng W, Jacob S, Delaney G, Barton M. An estimation of the population survival benefit of first-course chemotherapy for head and neck cancers. Ann Oncol 2017. [DOI: 10.1093/annonc/mdx374.043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Henry M, Roman D, Bardach D, Puhek J, Rehm B, Barton M, Lighter P. IDENTIFYING COMPLEX HIGH NEEDS PATIENT POPULATIONS FOR PERFORMANCE MEASUREMENT STRATIFICATION. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Liney GP, Dong B, Begg J, Vial P, Zhang K, Lee F, Walker A, Rai R, Causer T, Alnaghy SJ, Oborn BM, Holloway L, Metcalfe P, Barton M, Crozier S, Keall P. Technical Note: Experimental results from a prototype high-field inline MRI-linac. Med Phys 2017; 43:5188. [PMID: 27587049 DOI: 10.1118/1.4961395] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE The pursuit of real-time image guided radiotherapy using optimal tissue contrast has seen the development of several hybrid magnetic resonance imaging (MRI)-treatment systems, high field and low field, and inline and perpendicular configurations. As part of a new MRI-linac program, an MRI scanner was integrated with a linear accelerator to enable investigations of a coupled inline MRI-linac system. This work describes results from a prototype experimental system to demonstrate the feasibility of a high field inline MR-linac. METHODS The magnet is a 1.5 T MRI system (Sonata, Siemens Healthcare) was located in a purpose built radiofrequency (RF) cage enabling shielding from and close proximity to a linear accelerator with inline (and future perpendicular) orientation. A portable linear accelerator (Linatron, Varian) was installed together with a multileaf collimator (Millennium, Varian) to provide dynamic field collimation and the whole assembly built onto a stainless-steel rail system. A series of MRI-linac experiments was performed to investigate (1) image quality with beam on measured using a macropodine (kangaroo) ex vivo phantom; (2) the noise as a function of beam state measured using a 6-channel surface coil array; and (3) electron contamination effects measured using Gafchromic film and an electronic portal imaging device (EPID). RESULTS (1) Image quality was unaffected by the radiation beam with the macropodine phantom image with the beam on being almost identical to the image with the beam off. (2) Noise measured with a surface RF coil produced a 25% elevation of background intensity when the radiation beam was on. (3) Film and EPID measurements demonstrated electron focusing occurring along the centerline of the magnet axis. CONCLUSIONS A proof-of-concept high-field MRI-linac has been built and experimentally characterized. This system has allowed us to establish the efficacy of a high field inline MRI-linac and study a number of the technical challenges and solutions.
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Barton M, Lockhart S, Sidbury R, Wang R, Brandling-Bennett H. Trichodysplasia Spinulosa in a 7-Year-Old Boy Managed Using Physical Extraction of Keratin Spicules. Pediatr Dermatol 2017; 34:e74-e76. [PMID: 27990673 PMCID: PMC5788291 DOI: 10.1111/pde.13045] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Trichodysplasia spinulosa (TS) is an uncommon skin disease characterized by a folliculocentric papular eruption and keratin spine formation, classically appearing on the central face and ears. It occurs in immunosuppressed patients and is linked to a viral etiology. Diagnostic tests including polymerase chain reaction (PCR) are available for detection of the TS-associated polyomavirus. Effective treatment options include topical cidofovir and oral valganciclovir. We present a case diagnosed using PCR with skin scrapings and treated using physical extraction of the keratin spicules. Significant improvement was noted, suggesting a safe, cost-effective treatment alternative.
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Barton M, Santucci-Pereira J, Su Y, Russo J. Abstract P1-08-06: BC200 lncRNA is involved in the progression of triple negative breast cancer. Cancer Res 2017. [DOI: 10.1158/1538-7445.sabcs16-p1-08-06] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Long non coding RNAs (lncRNAs) have been identified as regulators of the cell cycle, apoptosis, and DNA damage among other processes that if deregulated, may lead to cancer by acting as proto-oncogenes, tumor suppressor genes, and drivers of metastatic transformation. Using RNA sequencing we have identified 42 differentially expressed lncRNAs from a healthy cohort of parous vs. nulliparous women. After bioinformatics and RT-qPCR analysis, we have focused on a vaguely studied lncRNA called BC200 that is highly expressed in the nulliparous postmenopausal breast tissue. It is known that BC200 lncRNA is overexpressed in invasive and pre-invasive breast cancer; however, its functional role in the initiation and progression of breast cancer is poorly understood. In the present work we provide insight on the role of BC200 in the context of luminal and triple negative breast cancer (TNBC). We have confirmed that BC200 is highly expressed in breast cancer tissue and in widely used breast cancer cell lines such as MCF7, T47D, MDAMB231, and Hs578T. Using a lentiviral system we successfully obtained cell lines which stably express BC200. Overexpression of BC200 increases proliferation, migration, and invasion potential in vitro in the cell lines tested, specifically luminal T47D and TNBC MDAMB231. Xenograft studies performed in the mammary fat pad of female SCID mice confirm the role of BC200 as a tumor promoter. Tumors in mice injected with MDAMB231 cells overexpressing BC200 were 4.5 times bigger than tumors in the control group in only 6 weeks when injecting 1 million cells. Moreover, we have determined, using reverse transcriptase PCR targeting genes less than 200 kb from the start site of BC200, that when BC200 is overexpressed, CALM2 is downregulated in both T47D and MDAMB231 cell lines. CALM2 or Calmodulin is a calcium binding protein that plays a role in signaling pathways, cell cycle progression, proliferation, and apoptosis. Mutations in CALM2 are associated with increased risk of breast cancer. Our positive results on Cis regulation are being expanded using chromatin isolation by RNA immunoprecipitation to determine BC200's genome wide regulation.
These results demonstrate the participation of BC200 lncRNA in the progression of breast cancer. Notably, BC200 regulates nearby genes that have an implication in cancer progression. BC200, identified in the normal breast tissue of nulliparous women, not only plays a key role in breast cancer progression but also provides a new insight in the preventive role of pregnancy by the downregulation of the expression of this lncRNA in the normal parous breast. [This work was supported by the NCI (National Cancer Institute) Core Grant CA06927 to Fox Chase Cancer Center and generous support from Christian - Diane Martin, the Flyers Wives, and Joseph - Barbara Breitman to Dr. J. Russo, MD].
Citation Format: Barton M, Santucci-Pereira J, Su Y, Russo J. BC200 lncRNA is involved in the progression of triple negative breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-08-06.
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Yap ML, Hanna TP, Shafiq J, Ferlay J, Bray F, Delaney GP, Barton M. The Benefits of Providing External Beam Radiotherapy in Low- and Middle-income Countries. Clin Oncol (R Coll Radiol) 2017; 29:72-83. [PMID: 27916340 DOI: 10.1016/j.clon.2016.11.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 11/07/2016] [Accepted: 11/07/2016] [Indexed: 01/04/2023]
Abstract
More than half of all cancer diagnoses worldwide occur in low- and middle-income countries (LMICs) and the incidence is projected to rise substantially within the next 20 years. Radiotherapy is a vital, cost-effective treatment for cancer; yet there is currently a huge deficit in radiotherapy services within these countries. The aim of this study was to estimate the potential outcome benefits if external beam radiotherapy was provided to all patients requiring such treatment in LMICs, according to the current evidence-based guidelines. Projected estimates of these benefits were calculated to 2035, obtained by applying the previously published Collaboration for Cancer Outcomes, Research and Evaluation (CCORE) demand and outcome benefit estimates to cancer incidence and projection data from the GLOBOCAN 2012 data. The estimated optimal radiotherapy utilisation rate for all LMICs was 50%. There were about 4.0 million cancer patients in LMICs who required radiotherapy in 2012. This number is projected to increase by 78% by 2035, a far steeper increase than the 38% increase expected in high-income countries. National radiotherapy benefits varied widely, and were influenced by case mix. The 5 year population local control and survival benefits for all LMICs, if radiotherapy was delivered according to guidelines, were estimated to be 9.6% and 4.4%, respectively, compared with no radiotherapy use. This equates to about 1.3 million patients who would derive a local control benefit in 2035, whereas over 615 000 patients would derive a survival benefit if the demand for radiotherapy in LMICs was met. The potential outcome benefits were found to be higher in LMICs. These results further highlight the urgent need to reduce the gap between the supply of, and demand for, radiotherapy in LMICs. We must attempt to address this 'silent crisis' as a matter of priority and the approach must consider the complex societal challenges unique to LMICs.
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Rosenblatt E, Prajogi GB, Barton M, Fidarova E, Eriksen JG, Haffty B, Millar BA, Bustam A, Zubizarreta E, Abdel-Wahab M. Need for Competency-Based Radiation Oncology Education in Developing Countries. ACTA ACUST UNITED AC 2017. [DOI: 10.4236/ce.2017.81006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Feain I, Shieh CC, White P, O'Brien R, Fisher S, Counter W, Lazarakis P, Stewart D, Downes S, Jackson M, Baxi S, Whelan B, Makhija K, Huang CY, Barton M, Keall P. Functional imaging equivalence and proof of concept for image-guided adaptive radiotherapy with fixed gantry and rotating couch. Adv Radiat Oncol 2016; 1:365-372. [PMID: 28740907 PMCID: PMC5514241 DOI: 10.1016/j.adro.2016.10.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 10/12/2016] [Accepted: 10/19/2016] [Indexed: 11/30/2022] Open
Abstract
Purpose The purpose of this article is to present the first imaging experiments to demonstrate the functional equivalence between a conventional rotational gantry and a fixed-beam imaging geometry, and the feasibility of an iterative image-reconstruction technique under gravitational deformation. Methods and materials Experiments were performed using an Elekta Axesse with Agility MLC and XVI, a custom-built rotating phantom stage, a Catphan QA phantom, and a porcine heart. For the imaging equivalence, a conventional cone beam computed tomography (CBCT) of the Catphan was acquired, as well as a set of 660 x-ray projections with a static gantry and rotating Catphan. Both datasets were reconstructed with the Feldkamp-Davis-Kress (FDK) algorithm, and the resultant volumetric images were compared using standard metrics. For imaging under gravitational deformation, a conventional CBCT of the Catphan and a set of 660 x-ray projections with a static gantry and rotating Catphan were also acquired with a porcine heart. The conventional CBCT was reconstructed using FDK. The projections that were acquired with the heart rotating were sorted into angular bins and reconstructed with prior image constrained compressed sensing using a deformation-blurred FDK prior. Deformation was quantified with B-spline transformation-based deformable image registration. Results For imaging equivalence, the difference between the two Catphan images was consistent with Poisson noise. For imaging under gravitational deformation, the conventional CBCT porcine heart image (ground truth at 0 degrees) matched the static gantry, rotating heart reconstruction with a mean magnitude of <3 mm and maximum magnitude of <5 mm of the deformation vector field. The mean deformation of the rotating heart was 3.0 to 8.9 mm, up to 16.1 mm maximum deformation. Deformation was mainly observed in the direction of gravity. Conclusions We have demonstrated imaging equivalence in cone beam CT reconstructions between rigid phantom images acquired with a conventional rotating gantry and with a fixed-gantry and rotating phantom. We have presented a method for image reconstruction under a fixed-beam imaging geometry using a deformable phantom.
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Rodin D, Hanna TP, Burger E, Zubizarreta E, Yap ML, Barton M, Atun R, Knaul F, Van Dyk J, Lievens Y, Gospodarowicz M, Jaffray D, Milosevic M. 11: Global Access to Radiotherapy for Cervical Cancer: The Cost of Inaction. Radiother Oncol 2016. [DOI: 10.1016/s0167-8140(16)33410-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Yap ML, Zubizarreta E, Bray F, Ferlay J, Barton M. Global Access to Radiotherapy Services: Have We Made Progress During the Past Decade? J Glob Oncol 2016; 2:207-215. [PMID: 28717703 PMCID: PMC5497622 DOI: 10.1200/jgo.2015.001545] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
PURPOSE The global incidence of cancer is rising, particularly in low- and middle-income countries. Radiotherapy is an important cancer treatment in the curative and palliative setting. We aimed to estimate the global demand for and supply of radiotherapy megavoltage machines (MVMs) and assess the changes in supply and demand during the past decade. MATERIALS AND METHODS Cancer incidences for 27 cancer types in 184 countries were extracted from the International Agency for Research on Cancer GLOBOCAN database. The Collaboration for Cancer Outcomes Research and Evaluation radiotherapy utilization rate (RTU) model was used to estimate the number of patients in each country with an indication for radiotherapy for each cancer type and estimate the demand for MVMs. The radiotherapy supply data were accessed from Directory of Radiotherapy Centres database maintained by the International Atomic Energy Agency. RESULTS RTU varied by country, from 32% in Mongolia to 59% in Comoros. The average optimal world RTU was 50%, equating to 7 million people in 2012 who would benefit from radiotherapy. There remains a deficit of more than 7,000 machines worldwide. During the past decade, the gap between radiotherapy demand and supply has widened in low-income countries. CONCLUSION RTU varies significantly between countries. Approximately half of all patients with cancer worldwide should receive radiotherapy; however, more than 2 million people are unable to access it because of a lack of MVMs. Low- and middle-income countries are particularly disadvantaged by this deficit.
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