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E.D.H. Gates J.S. Weinberg S.S. Prabhu J.S. Lin J. Hamilton J.D. Hazle G.N. Fuller V. Baladandayuthapani D.T. Fuentes D. Schellingerhout 《AJNR. American journal of neuroradiology》2021,42(1):102
BACKGROUND AND PURPOSE:Increased cellular density is a hallmark of gliomas, both in the bulk of the tumor and in areas of tumor infiltration into surrounding brain. Altered cellular density causes altered imaging findings, but the degree to which cellular density can be quantitatively estimated from imaging is unknown. The purpose of this study was to discover the best MR imaging and processing techniques to make quantitative and spatially specific estimates of cellular density.MATERIALS AND METHODS:We collected stereotactic biopsies in a prospective imaging clinical trial targeting untreated patients with gliomas at our institution undergoing their first resection. The data included preoperative MR imaging with conventional anatomic, diffusion, perfusion, and permeability sequences and quantitative histopathology on biopsy samples. We then used multiple machine learning methodologies to estimate cellular density using local intensity information from the MR images and quantitative cellular density measurements at the biopsy coordinates as the criterion standard.RESULTS:The random forest methodology estimated cellular density with R2 = 0.59 between predicted and observed values using 4 input imaging sequences chosen from our full set of imaging data (T2, fractional anisotropy, CBF, and area under the curve from permeability imaging). Limiting input to conventional MR images (T1 pre- and postcontrast, T2, and FLAIR) yielded slightly degraded performance (R2 = 0.52). Outputs were also reported as graphic maps.CONCLUSIONS:Cellular density can be estimated with moderate-to-strong correlations using MR imaging inputs. The random forest machine learning model provided the best estimates. These spatially specific estimates of cellular density will likely be useful in guiding both diagnosis and treatment.Increased cellular density (CD) is a hallmark of cancer and a key feature in histologic glioma analysis.1 Mapping cellular density throughout a tumor would be a valuable tool to probe how tumors infiltrate and analyze the transition between diseased and healthy brain. However, measuring CD requires tissue, which entails additional risks and is expensive to obtain. There is no currently accepted clinical algorithm to translate imaging data into quantitative assessments of CD.There is great need for a method to estimate CD noninvasively in human patients with gliomas. In this article, we describe the development of such a method using MR imaging data inputs by correlating with multiple biopsy specimens acquired during a prospective human clinical trial. We obtained comprehensive MR imaging, including conventional, diffusion, perfusion, and permeability imaging sequences. We used machine learning approaches to correlate imaging findings with CD measurements from pathology, devised an algorithm to estimate CD from MR imaging inputs, and generated CD maps for the visual display of the predictions. We identified the most informative imaging data subset. This work has multiple applications in the diagnosis and treatment of patients with gliomas: For example, the method can be used to guide biopsy, resection, and surgery and delineate tumor borderzones both pre- and postoperatively.2 相似文献
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Cheryl L. Rock PhD RD Cynthia A. Thomson PhD RD Kristen R. Sullivan MS MPH Carol L. Howe MD MLS Lawrence H. Kushi ScD Bette J. Caan DrPH Marian L. Neuhouser PhD RD Elisa V. Bandera MD PhD Ying Wang PhD Kimberly Robien PhD RD Karen M. Basen-Engquist PhD MPH Justin C. Brown PhD Kerry S. Courneya PhD Tracy E. Crane PhD RDN David O. Garcia PhD FACSM Barbara L. Grant MS RDN CSO FAND Kathryn K. Hamilton MA RDN CSO CDN FAND Sheri J. Hartman PhD Stacey A. Kenfield ScD Maria Elena Martinez PhD Jeffrey A. Meyerhardt MD MPH Larissa Nekhlyudov MD MPH Linda Overholser MD Alpa V. Patel PhD Bernardine M. Pinto PhD Mary E. Platek PhD RD CDN Erika Rees-Punia PhD MPH Colleen K. Spees PhD MEd RD LD FAND Susan M. Gapstur PhD Marjorie L. McCullough ScD RD 《CA: a cancer journal for clinicians》2022,72(3):230-262
The overall 5-year relative survival rate for all cancers combined is now 68%, and there are over 16.9 million survivors in the United States. Evidence from laboratory and observational studies suggests that factors such as diet, physical activity, and obesity may affect risk for recurrence and overall survival after a cancer diagnosis. The purpose of this American Cancer Society guideline is to provide evidence-based, cancer-specific recommendations for anthropometric parameters, physical activity, diet, and alcohol intake for reducing recurrence and cancer-specific and overall mortality. The audiences for this guideline are health care providers caring for cancer survivors as well as cancer survivors and their families. The guideline is intended to serve as a resource for informing American Cancer Society programs, health policy, and the media. Sources of evidence that form the basis of this guideline are systematic literature reviews, meta-analyses, pooled analyses of cohort studies, and large randomized clinical trials published since 2012. Recommendations for nutrition and physical activity during cancer treatment, informed by current practice, large cancer care organizations, and reviews of other expert bodies, are also presented. To provide additional context for the guidelines, the authors also include information on the relationship between health-related behaviors and comorbidities, long-term sequelae and patient-reported outcomes, and health disparities, with attention to enabling survivors' ability to adhere to recommendations. Approaches to meet survivors' needs are addressed as well as clinical care coordination and resources for nutrition and physical activity counseling after a cancer diagnosis. 相似文献
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Jesse I. Hamilton Yun Jiang Brendan Eck Mark Griswold Nicole Seiberlich 《NMR in biomedicine》2020,33(8)
This study introduces a technique called cine magnetic resonance fingerprinting (cine‐MRF) for simultaneous T1, T2 and ejection fraction (EF) quantification. Data acquired with a free‐running MRF sequence are retrospectively sorted into different cardiac phases using an external electrocardiogram (ECG) signal. A low‐rank reconstruction with a finite difference sparsity constraint along the cardiac motion dimension yields images resolved by cardiac phase. To improve SNR and precision in the parameter maps, these images are nonrigidly registered to the same phase and matched to a dictionary to generate T1 and T2 maps. Cine images for computing left ventricular volumes and EF are also derived from the same data. Cine‐MRF was tested in simulations using a numerical relaxation phantom. Phantom and in vivo scans of 19 subjects were performed at 3 T during a 10.9 seconds breath‐hold with an in‐plane resolution of 1.6 x 1.6 mm2 and 24 cardiac phases. Left ventricular EF values obtained with cine‐MRF agreed with the conventional cine images (mean bias ?1.0%). Average myocardial T1 times in diastole/systole were 1398/1391 ms with cine‐MRF, 1394/1378 ms with ECG‐triggered cardiac MRF (cMRF) and 1234/1212 ms with MOLLI; and T2 values were 30.7/30.3 ms with cine‐MRF, 32.6/32.9 ms with ECG‐triggered cMRF and 37.6/41.0 ms with T2‐prepared FLASH. Cine‐MRF and ECG‐triggered cMRF relaxation times were in good agreement. Cine‐MRF T1 values were significantly longer than MOLLI, and cine‐MRF T2 values were significantly shorter than T2‐prepared FLASH. In summary, cine‐MRF can potentially streamline cardiac MRI exams by combining left ventricle functional assessment and T1‐T2 mapping into one time‐efficient acquisition. 相似文献
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Ghazal Asswad Randa Alvi Sirhan Davies Katharine Jones Terry M. Hamilton David W. Brammer Caroline Lancaster Jeffrey Loh Christopher Tandon Sankalap Roland Nick 《European archives of oto-rhino-laryngology》2020,277(3):947-952
European Archives of Oto-Rhino-Laryngology - A multidisciplinary team (MDT) approach to cancer management is gold-standard. With an increasing disease incidence and growing research into human... 相似文献
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Facundo Davaro Jacob Roberts Allison May Coleman McFerrin Sameer Siddiqui Zachary Hamilton 《Journal of robotic surgery》2020,14(3):447-454
Partial nephrectomy is the mainstay of treatment for localized kidney cancer. A proportion of patients are upstaged post-operatively to locally advanced di 相似文献