309 results found
Saleem A, Shah SIA, Mangar SA, et al., 2023, Cognitive dysfunction in patients treated with androgen deprivation therapy: a multimodality functional imaging study to evaluate neuroinflammation, Prostate Cancer, Vol: 2023, ISSN: 2090-3111
BACKGROUND: Androgen deprivation therapy (ADT) for prostate cancer is implicated as a possible cause of cognitive impairment (CI). CI in dementia and Alzheimer's disease is associated with neuroinflammation. In this study, we investigated a potential role of neuroinflammation in ADT-related CI. METHODS: Patients with prostate cancer on ADT for ≥3 months were categorized as having ADT-emergent CI or normal cognition (NC) based on self-report at interview. Neuroinflammation was evaluated using positron emission tomography (PET) with the translocator protein (TSPO) radioligand [11C]-PBR28. [11C]-PBR28 uptake in various brain regions was quantified as standardized uptake value (SUVR, normalized to cerebellum) and related to blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI) choice-reaction time task (CRT) activation maps. RESULTS: Eleven patients underwent PET: four with reported CI (rCI), six with reported NC (rNC), and one status unrecorded. PET did not reveal any between-group differences in SUVR regionally or globally. There was no difference between groups on brain activation to the CRT. Regardless of the reported cognitive status, there was strong correlation between PET-TSPO signal and CRT activation in the hippocampus, amygdala, and medial cortex. CONCLUSIONS: We found no difference in neuroinflammation measured by PET-TSPO between patients with rCI and rNC. However, we speculate that the strong correlation between TSPO uptake and BOLD-fMRI activation in brain regions involved in memory and known to have high androgen-receptor expression mediating plasticity (hippocampus and amygdala) might reflect inflammatory effects of ADT with compensatory upregulated/increased synaptic functions. Further studies of this imaging readout are warranted to investigate ADT-related CI.
Omidvari N, Jones T, Price PM, et al., 2023, First-in-human immunoPET imaging of COVID-19 convalescent patients using dynamic total-body PET and a CD8-targeted minibody, Science Advances, Vol: 9, ISSN: 2375-2548
With most of the T cells residing in the tissue, not the blood, developing noninvasive methods for in vivo quantification of their biodistribution and kinetics is important for studying their role in immune response and memory. This study presents the first use of dynamic positron emission tomography (PET) and kinetic modeling for in vivo measurement of CD8+ T cell biodistribution in humans. A 89Zr-labeled CD8-targeted minibody (89Zr-Df-Crefmirlimab) was used with total-body PET in healthy individuals (N = 3) and coronavirus disease 2019 (COVID-19) convalescent patients (N = 5). Kinetic modeling results aligned with T cell-trafficking effects expected in lymphoid organs. Tissue-to-blood ratios from the first 7 hours of imaging were higher in bone marrow of COVID-19 convalescent patients compared to controls, with an increasing trend between 2 and 6 months after infection, consistent with modeled net influx rates and peripheral blood flow cytometry analysis. These results provide a promising platform for using dynamic PET to study the total-body immune response and memory.
Price P, Sullivan R, Ahmed A, et al., 2023, UK cancer care: a watershed moment and the need for urgent intervention, The Lancet Oncology, Vol: 24, Pages: 133-138, ISSN: 1213-9432
Barney S, Price P, Laird D, 2022, Lessons for Ukraine: how the international radiation therapy community can respond and support both now and in the future, Advances in Radiation Oncology, Vol: 7, Pages: 1-2, ISSN: 2452-1094
Feng T, Zhao Y, Shi H, et al., 2021, Total-body quantitative parametric imaging of early kinetics of ¹⁸F-FDG, Journal of Nuclear Medicine, Vol: 62, Pages: 738-744, ISSN: 0161-5505
Parametric imaging has been shown to provide better quantitation physiologically than SUV imaging in PET. With the increased sensitivity from a recently developed total-body PET scanner, whole-body scans with higher temporal resolution become possible for dynamic analysis and parametric imaging. In this paper, we focus on deriving the parameter k 1 using compartmental modeling and on developing a method to acquire whole-body (18)F-FDG PET parametric images using only the first 90 s of the postinjection scan data with the total-body PET system. Methods: Dynamic projections were acquired with a time interval of 1 s for the first 30 s and a time interval of 2 s for the following minute. Image-derived input functions were acquired from the reconstructed dynamic sequences in the ascending aorta. A 1-tissue-compartment model with 4 parameters (k 1, k 2, blood fraction, and delay time) was used. A maximum-likelihood-based estimation method was developed with the 1-tissue-compartment model solution. The accuracy of the acquired parameters was compared with the ones estimated using a 2-tissue-compartment irreversible model with 1-h-long data. Results: All 4 parametric images were successfully calculated using data from 2 volunteers. By comparing the time-activity curves acquired from the volumes of interest, we showed that the parameters estimated using our method were able to predict the time-activity curves of the early dynamics of (18)F-FDG in different organs. The delay-time effects for different organs were also clearly visible in the reconstructed delay-time image with delay variations of as large as 40 s. The estimated parameters using both 90-s data and 1-h data agreed well for k 1 and blood fraction, whereas a large difference in k 2 was found between the 90-s and 1-h data, suggesting k 2 cannot be reliably estimated from the 90-s scan. Conclusion: We have shown that with total-body PET and the increased sensitivity, it is possible to estimate parametric images base
Price P, Fleurent B, Barney SE, 2021, The Role of the Global Coalition for Radiotherapy in Political Advocacy for Radiation Therapy as a Cost-Effective and Underfunded Modality Around the World, Int J Radiat Oncol Biol Phys, Vol: 111, Pages: 23-26, ISSN: 1879-355X
Ashcroft S, Meeking K, Price P, 2021, Flash Survey on the Effect of COVID-19 on Radiotherapy Services in the UK - the Benefit of Social Media for Rapid Information Gathering for the Radiotherapy Community and Government, Clin Oncol (R Coll Radiol), Vol: 33, ISSN: 1433-2981
Total-body PET enables high-sensitivity imaging with dramatically improved signal-to-noise ratio. These enhanced performance characteristics allow for decreased PET scanning times acquiring data "total-body wide" and can be leveraged to decrease the amount of radiotracer required, thereby permitting more frequent imaging or longer imaging periods during radiotracer decay. Novel approaches to PET imaging of infectious diseases are emerging, including those that directly visualize pathogens in vivo and characterize concomitant immune responses and inflammation. Efforts to develop these imaging approaches are hampered by challenges of traditional imaging platforms, which may be overcome by novel total-body PET strategies.
Price P, 2021, Cancer during the COVID-19 pandemic: did we shout loudly enough and did anyone listen? A lasting legacy for nations, Eur J Cancer, Vol: 152, Pages: 243-244, ISSN: 1879-0852
Taheri A, Vishwanath V, Wong J, et al., 2020, The use of imaging and interventional radiology in modern oncology, Medicine, Vol: 48, Pages: 73-78, ISSN: 1357-3039
Radiology has become central in the diagnosis and management of patients in almost all subspecialties, but especially so in oncology. From its use as an initial screening tool to detect cancer, through to the staging and surveillance of disease, follow-up of post-treatment changes and delivery of minimal access therapies, radiology provides critical information about the status of patients' cancer care and treatment outcomes. Since the initial accidental discovery of X-rays by Wilhelm Röntgen in 1895, imaging technology has advanced rapidly, with multiple types of scans available; the specific advantages and limitations of each suited to particular pathologies, necessitating specialist interpretation by clinical radiologists. The main modalities of imaging are introduced here and their principle uses described.
Price P, Sikora K, 2020, Treatment of Cancer, 7th Edition, Taylor & Francis
Barcellini A, Filippi AR, Dal Mas F, et al., 2020, To a new normal in radiation oncology: looking back and planning forward, Tumori, Vol: 106, Pages: 440-444, ISSN: 2038-2529
Price P, Barney SE, 2020, Initiation of the Global Coalition for Radiotherapy during the COVID-19 pandemic, Lancet Oncol, Vol: 21, Pages: 752-753, ISSN: 1474-5488
Feng T, Zhao Y, Shi H, et al., 2019, The Effects of Delay on the Input Function for Early Dynamics in Total Body Parametric Imaging, Pages: 1-6
Badawi RD, Shi H, Hu P, et al., 2019, First Human Imaging Studies with the EXPLORER Total-Body PET Scanner, J Nucl Med, Vol: 60, Pages: 299-303, ISSN: 1535-5667
Within the EXPLORER Consortium, the construction of the world's first total-body PET/CT scanner has recently been completed. The 194-cm axial field of view of the EXPLORER PET/CT scanner is sufficient to cover, for the first time, the entire human adult body in a single acquisition in more than 99% of the population and allows total-body pharmacokinetic studies with frame durations as short as 1 s. The large increase in sensitivity arising from total-body coverage as well as increased solid angle for detection at any point within the body allows whole-body (18)F-FDG PET studies to be acquired with unprecedented count density, improving the signal-to-noise ratio of the resulting images. Alternatively, the sensitivity gain can be used to acquire diagnostic PET images with very small amounts of activity in the field of view (25 MBq, 0.7 mCi or less), with very short acquisition times ( approximately 1 min or less) or at later time points after the tracer's administration. We report here on the first human imaging studies on the EXPLORER scanner using a range of different protocols that provide initial evidence in support of these claims. These case studies provide the foundation for future carefully controlled trials to quantitatively evaluate the improvements possible through total-body PET imaging.
Wilson HP, Price PM, Ashkan K, et al., 2018, CyberKnife Radiosurgery of Skull-base Tumors: A UK Center Experience, Cureus, Vol: 10, ISSN: 2168-8184
The study aim was to evaluate patient individualized Cyberknife(R) treatment for heterogeneous skull-base tumors. Patients treated between 2009 and 2013 at The Harley Street Clinic were studied. In total, 66 patients received 15-30 Gy in 1-5 fractions to a median planning target volume (PTV) of 6.4 cc, including patients with secondary, multiple, residual and recurrent tumors, and those with tumors of uncertain pathological type. Outcome analysis was pragmatically restricted to 35 patients who had single, primary tumors treated with curative intent, and sufficient diagnostic and outcome information. Sixteen vestibular schwannoma patients with median PTV 3.8 cc (range 0.81-19.6) received 18-25 Gy in 3-5 fractions: 81% showed no acute toxicity, 50% reported no late toxicity, 71% of symptoms were stable/improved and local control was 100% at 11.4 months median follow-up. Twelve meningioma patients with median PTV of 5.5 cc (range 0.68-22.3) received 17-30 Gy in 1-5 fractions: 83% experienced no acute toxicity, 33% reported no late toxicity, 88% of symptoms were stable/improved and local control was 100% at 22.1 months median follow-up. Seven patients with other tumor types with median PTV of 24.3 cc (range 7.6-100.5) received 15-28.5 Gy in 1-5 fractions: 57% experienced no acute toxicity, 57% reported no late toxicities, 66% of symptoms were stable and local control was 43% at 14.9 months median follow-up. When tumor types were considered together, smaller tumors (PTV < 6.4 cc) showed reduced acute toxicity (p = 0.01). Overall, smaller benign tumors showed low acute toxicity, excellent local control, and good symptom management: a focus on enhanced neurological preservation may refine outcomes. For other tumor types outcome was encouraging: a focus on optimal dose and fractionation scheduling may reduce toxicity and improve local control. Individual patient experiences are detailed where valuable lessons were gained for optimizing local control and minimizing toxici
Goldsmith C, Plowman PN, Green MM, et al., 2018, Stereotactic ablative radiotherapy (SABR) as primary, adjuvant, consolidation and re-treatment option in pancreatic cancer: scope for dose escalation and lessons for toxicity, Radiat Oncol, Vol: 13, ISSN: 1748-717X
BACKGROUND: Stereotactic ablative radiotherapy (SABR) offers an alternative treatment for pancreatic cancer, with the potential for improved tumour control and reduced toxicity compared with conventional therapies. However, optimal dose planning and delivery strategies are unelucidated and gastro-intestinal (GI) toxicity remains a key concern. METHODS: Patients with inoperable non-metastatic pancreatic cancer who received CyberKnife(R) SABR (18-36 Gy) in three fractions as primary, adjuvant, consolidation or re-treatment options were studied. Patient individualised planning and delivery variables were collected and their impact on patient outcome examined. Linear-quadratic (LQ) radiobiology modelling methods were applied to assess SABR parameters against a conventional fractionated radiotherapy schedule. RESULTS: In total 42 patients were included, 37 (88%) of whom had stage T4 disease. SABR was used > 6 months post-primary therapy to re-treat residual disease in 11 (26.2%) patients and relapsed disease in nine (21.4%) patients. SABR was an adjuvant to other primary therapy for 14 (33.3%) patients and was the sole primary therapy for eight (19.0%) patients. The mean (95% CI) planning target volume (PTV), prescription isodose, percentage cover, minimum dose to PTV and biological effective dose (BED) were 76.3(63.8-88.7) cc, 67.3(65.2-69.5)%, 96.6(95.5-97.7)%, 22.3(21.0-23.6) Gy and 50.3(47.7-53.0) Gy, respectively. Only 3/37 (8.1%) patients experienced Grade 3 acute toxicities. Two (4.8%) patients converted to resectable status and median freedom-from-local-progression (FFLP) and overall survival (OS) were 9.8 and 8.4 months, respectively. No late toxicity was experienced in 27/32 (84.4%) patients; however, four (12.5%) patients - of whom two had particularly large PTV, two had sub-optimal number of fiducials and three breached organ-at-risk (OAR) constraints-showed Grade 4 duodenal toxicities. Longer delivery time, extended treatment course and reduced percentage
Price P, 2018, Current and future challenges facing medico-legal experts – An expert’s view, Journal of Patient Safety and Risk Management, Vol: 23, Pages: 109-113
McMullen C, Nielsen M, Firemark A, et al., 2018, Designing for impact: identifying stakeholder-driven interventions to support recovery after major cancer surgery, Support Care Cancer, Vol: 26, Pages: 4067-4076, ISSN: 1433-7339
PURPOSE: Complex bladder and colorectal cancer surgeries are associated with significant patient morbidity, yet few resources exist to prepare patients for the high levels of distress and complications they may experience. After ethnographic research to identify design challenges, we held a user-centered design (UCD) workshop to begin to develop patient- and caregiver-centered interventions to support preparation for and recovery after complex cancer surgery. METHODS: Concepts that emerged from brainstorming sessions were visually represented on storyboards and rated. Highly scored concepts were further developed in break-out prototyping sessions and then presented to the entire group for review in person and during subsequent webinars. We collected workshop products (worksheets, prototypes, and recordings) for analysis to identify opportunities for intervention. The workshop, held in late 2014, was attended by three colorectal/oncologic surgeons, three urologic surgeons, five ostomy nurses, one quality improvement leader, three patients, one caregiver, and three experienced UCD facilitators. RESULTS: Three opportunity areas were identified: (1) enhanced patient education including tele-health and multi-media tools (available at hospitals/clinics or online in any setting), (2) personalized discharge assessment and care planning, and (3) integrated symptom monitoring and educational interventions. Stakeholders reached consensus that enhanced patient education was the most important direction for subsequent intervention development. CONCLUSIONS: We engaged diverse stakeholders in a participatory, UCD process and concluded that research and practice improvement should prioritize the development of educational interventions in the pre-operative period to set the groundwork for improving appropriate self-care during recovery from major colorectal and bladder cancer surgeries.
Goldsmith C, Green MM, Middleton B, et al., 2018, Evaluation of CyberKnife(R) Fiducial Tracking Limitations to Assist Targeting Accuracy: A Phantom Study with Fiducial Displacement, Cureus, Vol: 10, ISSN: 2168-8184
Introduction The underlying assumptions of the CyberKnife(R) (Accuray, Sunnyvale, CA, US) fiducial tracking system are: i) fiducial positions are accurately detected; ii) inter-fiducial geometry remains consistent (rigid); iii) inter-fiducial geometric array changes are detected and either accommodated with corrections or treatment is interrupted. However: i) soft-tissue targets are deformable & fiducial migration is possible; ii) the accuracy of the tracking system has not previously been examined with fiducial displacement; iii) treatment interruptions may occur due to inter-fiducial geometric changes, but there is little information available to assist subsequent troubleshooting. The purpose of this study was to emulate a clinical target defined with a two, three, or four-fiducial array where one fiducial is displaced to mimic a target deformation or fiducial migration scenario. The objectives: evaluate the fiducial positioning accuracy, array interpretation, & corresponding corrections of the CyberKnife system, with the aim of assisting troubleshooting following fiducial displacement. Methods A novel solid-water phantom was constructed with three fixed fiducials (F1,F2,F3) & one moveable fiducial (F4), arranged as if placed to track an imaginary clinical target. Using either two fiducials (F1,F4), different combinations of three fiducials (F1,F2,F4; F1,F3,F4; F2,F3,F4) or four fiducials (F1,F2,F3,F4), repeat experiments were conducted where F4 was displaced inferiorly at 2-mm intervals from 0-16 mm. Data were acquired at each position of F4, including rigid body errors (RBE), fiducial x, y, & z coordinate displacements, six degrees of freedom (DOF) corrections, & robot center-of-mass (COM) translation corrections. Results Maximum positioning difference (mean+/-SD) between the reference and live x, y, & z coordinates for the three fixed fiducials was 0.08+/-0.30 mm, confirming good accuracy for fixed fiducial registration. For two fiducial
Cherry SR, Badawi RD, Karp JS, et al., 2017, Total-body imaging: Transforming the role of positron emission tomography, Sci Transl Med, Vol: 9, ISSN: 1946-6242
The first total-body positron emission tomography (TB-PET) scanner represents a radical change for experimental medicine and diagnostic health care.
Rice L, Goldsmith C, Green MM, et al., 2017, An effective deep-inspiration breath-hold radiotherapy technique for left-breast cancer: impact of post-mastectomy treatment, nodal coverage, and dose schedule on organs at risk, Breast Cancer (Dove Med Press), Vol: 9, Pages: 437-446, ISSN: 1179-1314
BACKGROUND: We developed, applied, and prospectively evaluated a novel deep-inspiration breath-hold (DIBH) screening and delivery technique to optimize cardiac sparing in left-breast radiotherapy (RT) at our clinic. The impact of set-up and dose variables upon organs at risk (OAR) dose in DIBH RT was investigated. METHODS AND MATERIALS: All patients with left-breast cancer referred between 2011 and 2014 - of all disease stages, set-up variations, and dose prescriptions - were included. Radiographers used simple screening criteria at CT simulation, to systematically assess patients for obvious DIBH benefit and capability. Selected patients received forward-planned intensity-modulated RT (IMRT) based on a DIBH CT scan. A 3D-surface monitoring system with visual feedback assured reproducible DIBH positioning during gated radiation delivery. Patient, target set-up, and OAR dose information were collected at treatment. RESULTS: Of 272 patients who were screened, 4 withdrew, 56 showed no obvious advantage, and 56 showed benefit but had suitability issues; 156 patients were selected and successfully completed DIBH treatment. The technique was compatible with complex set-up and optimal target coverage was maintained. Comparison of free-breathing (FB) and DIBH treatment plans in the first five patients enrolled confirmed DIBH reduced heart radiation by ~80% (p = 0.032). Low OAR doses were achieved overall: the mean (95% confidence interval [CI]) heart dose was 1.17 (1.12-1.22) Gy, and the mean ipsilateral lung dose was 5.26 (5.01-5.52) Gy. Patients who underwent a standard radiation schedule (40 Gy/15#) after breast-conserving surgery had the lowest OAR doses: post-mastectomy treatment, simultaneous supraclavicular (SCV) node coverage, and alternative dose schedule (50 Gy/25#) were interrelated variables associated with increased OAR risk and compromised ipsilateral lung dose constraints. CONCLUSION: The DIBH technique was successfully implemented and resulted in optimally l
Rembielak A GM, 2016, Diagnostic and therapeutic imaging in oncology (invited to submit updated version of 2011 article), Medicine Oncology, Vol: 44
Goldsmith C, Price P, Cross T, et al., 2016, Dose Volume Histogram analysis of stereotactic body radiotherapy treatment of pancreatic cancer: a focus on duodenal dose constraints., Seminars in radiation Oncology, Vol: 2016 April 26 (2), Pages: 149-156
Shah SIMRANA, Jin ANDI, Wilson HANNAHCP, et al., 2015, Novel Computed Tomography-based Metric Reliably Estimates bone Strength, Offering Potentially Meaningful Enhancement in Clinical Fracture Risk Prediction, European Journal of Medicine, Vol: 10, Pages: 214-220, ISSN: 2310-3434
Osteoporosis with resultant fractures is a major global health problem with huge socioeconomicimplications for patients, families and healthcare services. Areal (2D bone mineraldensity (BMD) assessment is commonly used for predicting such fracture risk, but is unreliable,estimating only about 50% of bone strength. By contrast, computed tomography (CT) basedtechniques could provide improved metrics for estimating bone strength such as bone volumefraction (BVF; a 3D volumetric measure of mineralised bone), enabling cheap, safe and reliablestrategies for clinical application, and to help divert resources to patients identified as most likelyto benefit, meeting an unmet need.Here we describe a novel method for measuring BVF at clinical-CT like low-resolution(550µm voxel size). Femoral heads (n=8) were micro-CT scanned ex-vivo. Micro-CT data weredowngraded in resolution from 30µm to 550µm voxel size and BVF calculated at high and lowresolution. Experimental mechanical testing was applied to measure ex vivo bone strength ofsamples. BVF measures collected at high-resolution showed high correlation (correlationcoefficient r2=0.95) with low-resolution data. Low-resolution BVF metrics showed high correlation(r2=0.96) with calculated sample strength. These results demonstrate that measuring BVF at lowresolution is feasible, which also predicts bone strength. Measures of BVF should be useful for clinically estimating bone strength and fracture risk. The method needs to be validated using clinical CT scans.
Abel M, Ahmed H, Leen E, et al., 2015, Ultrasound-guided trans-rectal high intensity focused ultrasound (HIFU) for advanced cervical cancer ablation is feasible: a case report, Journal of Therapeutic Ultrasound, Vol: (2015) 3:21
Wilson W SSIA, 2015, Re: State-Of-The-Art Treatment in Castration-Resistant Prostate Cancer – Forward to the past – Again, European Journal of Medicine
Shah I, Jin A, Wilson HCP, et al., 2015, Novel Computed Tomography-based Metric Reliably Estimates bone Strength, Offering Potentially Meaningful Enhancement in Clinical Fracture Risk Prediction, European Journal of Medicine, Vol: Vol. 10
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