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Denholm J, Schreiber BA, Jaeckle F, Wicks MN, Benbow EW, Bracey TS, Chan JYH, Farkas L, Fryer E, Gopalakrishnan K, Hughes CA, Kirkwood KJ, Langman G, Mahler-Araujo B, McMahon RFT, Myint KLW, Natu S, Robinson A, Sanduka A, Sheppard KA, Tsang YW, Arends MJ, Soilleux EJ. CD, or not CD, that is the question: a digital interobserver agreement study in coeliac disease. BMJ Open Gastroenterol 2024; 11:e001252. [PMID: 38302475 PMCID: PMC10870791 DOI: 10.1136/bmjgast-2023-001252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 12/11/2023] [Indexed: 02/03/2024] Open
Abstract
OBJECTIVE Coeliac disease (CD) diagnosis generally depends on histological examination of duodenal biopsies. We present the first study analysing the concordance in examination of duodenal biopsies using digitised whole-slide images (WSIs). We further investigate whether the inclusion of immunoglobulin A tissue transglutaminase (IgA tTG) and haemoglobin (Hb) data improves the interobserver agreement of diagnosis. DESIGN We undertook a large study of the concordance in histological examination of duodenal biopsies using digitised WSIs in an entirely virtual reporting setting. Our study was organised in two phases: in phase 1, 13 pathologists independently classified 100 duodenal biopsies (40 normal; 40 CD; 20 indeterminate enteropathy) in the absence of any clinical or laboratory data. In phase 2, the same pathologists examined the (re-anonymised) WSIs with the inclusion of IgA tTG and Hb data. RESULTS We found the mean probability of two observers agreeing in the absence of additional data to be 0.73 (±0.08) with a corresponding Cohen's kappa of 0.59 (±0.11). We further showed that the inclusion of additional data increased the concordance to 0.80 (±0.06) with a Cohen's kappa coefficient of 0.67 (±0.09). CONCLUSION We showed that the addition of serological data significantly improves the quality of CD diagnosis. However, the limited interobserver agreement in CD diagnosis using digitised WSIs, even after the inclusion of IgA tTG and Hb data, indicates the importance of interpreting duodenal biopsy in the appropriate clinical context. It further highlights the unmet need for an objective means of reproducible duodenal biopsy diagnosis, such as the automated analysis of WSIs using artificial intelligence.
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Affiliation(s)
- James Denholm
- Department of Pathology, University of Cambridge, Cambridge, UK
- Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge, UK
- Lyzeum Ltd, Cambridge, UK
| | - Benjamin A Schreiber
- Department of Pathology, University of Cambridge, Cambridge, UK
- Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge, UK
| | - Florian Jaeckle
- Department of Pathology, University of Cambridge, Cambridge, UK
- Lyzeum Ltd, Cambridge, UK
| | - Mike N Wicks
- Department of Pathology, The University of Edinburgh College of Medicine and Veterinary Medicine, Edinburgh, UK
| | - Emyr W Benbow
- Division of Medical Education, The University of Manchester, Manchester, UK
- Department of Histopathology, Manchester University NHS Foundation Trust, Manchester, UK
| | - Tim S Bracey
- Department of Diagnostic and Molecular Pathology, Royal Cornwall Hospitals NHS Trust, Truro, UK
- University Hospitals Plymouth NHS Trust, Plymouth, UK
| | - James Y H Chan
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Lorant Farkas
- Department of Pathology, Akershus University Hospital, Nordbyhagen, Norway
- Institute of Clinical Medicine, University of Oslo, Nordbyhagen, Norway
| | - Eve Fryer
- Department of Cellular Pathology, Oxford University Hospitals NHS foundation Trust, Oxford, UK
| | - Kishore Gopalakrishnan
- Department of Histopathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Caroline A Hughes
- Department of Cellular Pathology, Oxford University Hospitals NHS foundation Trust, Oxford, UK
| | | | - Gerald Langman
- Department of Cellular Pathology, Heartlands Hospital, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Betania Mahler-Araujo
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
- MRC Institute of Metabolic Science, Wellcome Trust, Cambridge, UK
| | - Raymond F T McMahon
- Division of Medical Education, The University of Manchester, Manchester, UK
- Department of Histopathology, Manchester University NHS Foundation Trust, Manchester, UK
| | - Khun La Win Myint
- Department of Pathology, Queen Elizabeth University Hospital, Glasgow, UK
| | - Sonali Natu
- University Hospital of North Tees, North Tees and Hartlepool NHS Foundation Trust, Stockton on Tees, UK
| | - Andrew Robinson
- Department of Histopathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Ashraf Sanduka
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Katharine A Sheppard
- Department of Cellular Pathology, Oxford University Hospitals NHS foundation Trust, Oxford, UK
| | - Yee Wah Tsang
- Department of Histopathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Mark J Arends
- Division of Pathology, University of Edinburgh, Edinburgh, UK
| | - Elizabeth J Soilleux
- Department of Pathology, University of Cambridge, Cambridge, UK
- Lyzeum Ltd, Cambridge, UK
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Bilal M, Tsang YW, Ali M, Graham S, Hero E, Wahab N, Dodd K, Sahota H, Wu S, Lu W, Jahanifar M, Robinson A, Azam A, Benes K, Nimir M, Hewitt K, Bhalerao A, Eldaly H, Raza SEA, Gopalakrishnan K, Minhas F, Snead D, Rajpoot N. Development and validation of artificial intelligence-based prescreening of large-bowel biopsies taken in the UK and Portugal: a retrospective cohort study. Lancet Digit Health 2023; 5:e786-e797. [PMID: 37890902 DOI: 10.1016/s2589-7500(23)00148-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 07/10/2023] [Accepted: 07/25/2023] [Indexed: 10/29/2023]
Abstract
BACKGROUND Histopathological examination is a crucial step in the diagnosis and treatment of many major diseases. Aiming to facilitate diagnostic decision making and improve the workload of pathologists, we developed an artificial intelligence (AI)-based prescreening tool that analyses whole-slide images (WSIs) of large-bowel biopsies to identify typical, non-neoplastic, and neoplastic biopsies. METHODS This retrospective cohort study was conducted with an internal development cohort of slides acquired from a hospital in the UK and three external validation cohorts of WSIs acquired from two hospitals in the UK and one clinical laboratory in Portugal. To learn the differential histological patterns from digitised WSIs of large-bowel biopsy slides, our proposed weakly supervised deep-learning model (Colorectal AI Model for Abnormality Detection [CAIMAN]) used slide-level diagnostic labels and no detailed cell or region-level annotations. The method was developed with an internal development cohort of 5054 biopsy slides from 2080 patients that were labelled with corresponding diagnostic categories assigned by pathologists. The three external validation cohorts, with a total of 1536 slides, were used for independent validation of CAIMAN. Each WSI was classified into one of three classes (ie, typical, atypical non-neoplastic, and atypical neoplastic). Prediction scores of image tiles were aggregated into three prediction scores for the whole slide, one for its likelihood of being typical, one for its likelihood of being non-neoplastic, and one for its likelihood of being neoplastic. The assessment of the external validation cohorts was conducted by the trained and frozen CAIMAN model. To evaluate model performance, we calculated area under the convex hull of the receiver operating characteristic curve (AUROC), area under the precision-recall curve, and specificity compared with our previously published iterative draw and rank sampling (IDaRS) algorithm. We also generated heat maps and saliency maps to analyse and visualise the relationship between the WSI diagnostic labels and spatial features of the tissue microenvironment. The main outcome of this study was the ability of CAIMAN to accurately identify typical and atypical WSIs of colon biopsies, which could potentially facilitate automatic removing of typical biopsies from the diagnostic workload in clinics. FINDINGS A randomly selected subset of all large bowel biopsies was obtained between Jan 1, 2012, and Dec 31, 2017. The AI training, validation, and assessments were done between Jan 1, 2021, and Sept 30, 2022. WSIs with diagnostic labels were collected between Jan 1 and Sept 30, 2022. Our analysis showed no statistically significant differences across prediction scores from CAIMAN for typical and atypical classes based on anatomical sites of the biopsy. At 0·99 sensitivity, CAIMAN (specificity 0·5592) was more accurate than an IDaRS-based weakly supervised WSI-classification pipeline (0·4629) in identifying typical and atypical biopsies on cross-validation in the internal development cohort (p<0·0001). At 0·99 sensitivity, CAIMAN was also more accurate than IDaRS for two external validation cohorts (p<0·0001), but not for a third external validation cohort (p=0·10). CAIMAN provided higher specificity than IDaRS at some high-sensitivity thresholds (0·7763 vs 0·6222 for 0·95 sensitivity, 0·7126 vs 0·5407 for 0·97 sensitivity, and 0·5615 vs 0·3970 for 0·99 sensitivity on one of the external validation cohorts) and showed high classification performance in distinguishing between neoplastic biopsies (AUROC 0·9928, 95% CI 0·9927-0·9929), inflammatory biopsies (0·9658, 0·9655-0·9661), and atypical biopsies (0·9789, 0·9786-0·9792). On the three external validation cohorts, CAIMAN had AUROC values of 0·9431 (95% CI 0·9165-0·9697), 0·9576 (0·9568-0·9584), and 0·9636 (0·9615-0·9657) for the detection of atypical biopsies. Saliency maps supported the representation of disease heterogeneity in model predictions and its association with relevant histological features. INTERPRETATION CAIMAN, with its high sensitivity in detecting atypical large-bowel biopsies, might be a promising improvement in clinical workflow efficiency and diagnostic decision making in prescreening of typical colorectal biopsies. FUNDING The Pathology Image Data Lake for Analytics, Knowledge and Education Centre of Excellence; the UK Government's Industrial Strategy Challenge Fund; and Innovate UK on behalf of UK Research and Innovation.
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Affiliation(s)
- Mohsin Bilal
- Tissue Image Analytics Centre, Department of Computer Science, University of Warwick, Coventry, UK; Department of Artificial Intelligence and Data Science, National University of Computer and Emerging Sciences, Islamabad, Pakistan
| | - Yee Wah Tsang
- Department of Pathology, University Hospitals Coventry and Warwickshire National Health Service Trust, Coventry, UK
| | - Mahmoud Ali
- Department of Pathology, University Hospitals Coventry and Warwickshire National Health Service Trust, Coventry, UK
| | - Simon Graham
- Tissue Image Analytics Centre, Department of Computer Science, University of Warwick, Coventry, UK; Histofy, Birmingham, UK
| | - Emily Hero
- Department of Pathology, University Hospitals Coventry and Warwickshire National Health Service Trust, Coventry, UK; Department of Pathology, University Hospitals of Leicester National Health Service Trust, Leicester, UK
| | - Noorul Wahab
- Tissue Image Analytics Centre, Department of Computer Science, University of Warwick, Coventry, UK
| | - Katherine Dodd
- Department of Pathology, University Hospitals Coventry and Warwickshire National Health Service Trust, Coventry, UK
| | - Harvir Sahota
- Department of Pathology, University Hospitals Coventry and Warwickshire National Health Service Trust, Coventry, UK
| | - Shaobin Wu
- Department of Pathology, East Suffolk and North Essex National Health Service Foundation Trust, Colchester, UK
| | - Wenqi Lu
- Tissue Image Analytics Centre, Department of Computer Science, University of Warwick, Coventry, UK
| | - Mostafa Jahanifar
- Tissue Image Analytics Centre, Department of Computer Science, University of Warwick, Coventry, UK
| | - Andrew Robinson
- Department of Pathology, University Hospitals Coventry and Warwickshire National Health Service Trust, Coventry, UK
| | - Ayesha Azam
- Department of Pathology, University Hospitals Coventry and Warwickshire National Health Service Trust, Coventry, UK
| | - Ksenija Benes
- Department of Pathology, The Royal Wolverhampton National Health Service Trust, Wolverhampton, UK
| | - Mohammed Nimir
- Department of Pathology, University Hospitals Coventry and Warwickshire National Health Service Trust, Coventry, UK
| | - Katherine Hewitt
- Department of Pathology, University Hospitals Coventry and Warwickshire National Health Service Trust, Coventry, UK
| | - Abhir Bhalerao
- Tissue Image Analytics Centre, Department of Computer Science, University of Warwick, Coventry, UK
| | - Hesham Eldaly
- Department of Pathology, University Hospitals Coventry and Warwickshire National Health Service Trust, Coventry, UK
| | - Shan E Ahmed Raza
- Tissue Image Analytics Centre, Department of Computer Science, University of Warwick, Coventry, UK
| | - Kishore Gopalakrishnan
- Department of Pathology, University Hospitals Coventry and Warwickshire National Health Service Trust, Coventry, UK
| | - Fayyaz Minhas
- Tissue Image Analytics Centre, Department of Computer Science, University of Warwick, Coventry, UK
| | - David Snead
- Warwick Medical School, University of Warwick, Coventry, UK; Department of Pathology, University Hospitals Coventry and Warwickshire National Health Service Trust, Coventry, UK; Histofy, Birmingham, UK
| | - Nasir Rajpoot
- Tissue Image Analytics Centre, Department of Computer Science, University of Warwick, Coventry, UK; Department of Pathology, University Hospitals Coventry and Warwickshire National Health Service Trust, Coventry, UK; Histofy, Birmingham, UK; The Alan Turing Institute, London, UK.
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Graham S, Minhas F, Bilal M, Ali M, Tsang YW, Eastwood M, Wahab N, Jahanifar M, Hero E, Dodd K, Sahota H, Wu S, Lu W, Azam A, Benes K, Nimir M, Hewitt K, Bhalerao A, Robinson A, Eldaly H, Raza SEA, Gopalakrishnan K, Snead D, Rajpoot N. Screening of normal endoscopic large bowel biopsies with interpretable graph learning: a retrospective study. Gut 2023; 72:1709-1721. [PMID: 37173125 PMCID: PMC10423541 DOI: 10.1136/gutjnl-2023-329512] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 04/15/2023] [Indexed: 05/15/2023]
Abstract
OBJECTIVE To develop an interpretable artificial intelligence algorithm to rule out normal large bowel endoscopic biopsies, saving pathologist resources and helping with early diagnosis. DESIGN A graph neural network was developed incorporating pathologist domain knowledge to classify 6591 whole-slides images (WSIs) of endoscopic large bowel biopsies from 3291 patients (approximately 54% female, 46% male) as normal or abnormal (non-neoplastic and neoplastic) using clinically driven interpretable features. One UK National Health Service (NHS) site was used for model training and internal validation. External validation was conducted on data from two other NHS sites and one Portuguese site. RESULTS Model training and internal validation were performed on 5054 WSIs of 2080 patients resulting in an area under the curve-receiver operating characteristic (AUC-ROC) of 0.98 (SD=0.004) and AUC-precision-recall (PR) of 0.98 (SD=0.003). The performance of the model, named Interpretable Gland-Graphs using a Neural Aggregator (IGUANA), was consistent in testing over 1537 WSIs of 1211 patients from three independent external datasets with mean AUC-ROC=0.97 (SD=0.007) and AUC-PR=0.97 (SD=0.005). At a high sensitivity threshold of 99%, the proposed model can reduce the number of normal slides to be reviewed by a pathologist by approximately 55%. IGUANA also provides an explainable output highlighting potential abnormalities in a WSI in the form of a heatmap as well as numerical values associating the model prediction with various histological features. CONCLUSION The model achieved consistently high accuracy showing its potential in optimising increasingly scarce pathologist resources. Explainable predictions can guide pathologists in their diagnostic decision-making and help boost their confidence in the algorithm, paving the way for its future clinical adoption.
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Affiliation(s)
- Simon Graham
- Department of Computer Science, University of Warwick, Coventry, UK
- Histofy Ltd, Birmingham, UK
| | - Fayyaz Minhas
- Department of Computer Science, University of Warwick, Coventry, UK
| | - Mohsin Bilal
- Department of Computer Science, University of Warwick, Coventry, UK
| | - Mahmoud Ali
- Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Yee Wah Tsang
- Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Mark Eastwood
- Department of Computer Science, University of Warwick, Coventry, UK
| | - Noorul Wahab
- Department of Computer Science, University of Warwick, Coventry, UK
| | | | - Emily Hero
- Department of Pathology, University Hospitals of Leicester NHS Trust, Leicester, UK
| | - Katherine Dodd
- Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Harvir Sahota
- Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Shaobin Wu
- Department of Pathology, East Suffolk and North Essex NHS Foundation Trust, Colchester, UK
| | - Wenqi Lu
- Department of Computer Science, University of Warwick, Coventry, UK
| | - Ayesha Azam
- Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Ksenija Benes
- Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
- Department of Pathology, Royal Wolverhampton Hospitals NHS Trust, Wolverhampton, UK
| | - Mohammed Nimir
- Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Katherine Hewitt
- Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Abhir Bhalerao
- Department of Computer Science, University of Warwick, Coventry, UK
| | - Andrew Robinson
- Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Hesham Eldaly
- Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | | | - Kishore Gopalakrishnan
- Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - David Snead
- Histofy Ltd, Birmingham, UK
- Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
- Division of Biomedical Sciences, University of Warwick Warwick Medical School, Coventry, UK
| | - Nasir Rajpoot
- Department of Computer Science, University of Warwick, Coventry, UK
- Histofy Ltd, Birmingham, UK
- Department of Pathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
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4
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Wahab N, Miligy IM, Dodd K, Sahota H, Toss M, Lu W, Jahanifar M, Bilal M, Graham S, Park Y, Hadjigeorghiou G, Bhalerao A, Lashen AG, Ibrahim AY, Katayama A, Ebili HO, Parkin M, Sorell T, Raza SEA, Hero E, Eldaly H, Tsang YW, Gopalakrishnan K, Snead D, Rakha E, Rajpoot N, Minhas F. Semantic annotation for computational pathology: multidisciplinary experience and best practice recommendations. J Pathol Clin Res 2022; 8:116-128. [PMID: 35014198 PMCID: PMC8822374 DOI: 10.1002/cjp2.256] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 11/25/2021] [Accepted: 12/10/2021] [Indexed: 02/06/2023]
Abstract
Recent advances in whole‐slide imaging (WSI) technology have led to the development of a myriad of computer vision and artificial intelligence‐based diagnostic, prognostic, and predictive algorithms. Computational Pathology (CPath) offers an integrated solution to utilise information embedded in pathology WSIs beyond what can be obtained through visual assessment. For automated analysis of WSIs and validation of machine learning (ML) models, annotations at the slide, tissue, and cellular levels are required. The annotation of important visual constructs in pathology images is an important component of CPath projects. Improper annotations can result in algorithms that are hard to interpret and can potentially produce inaccurate and inconsistent results. Despite the crucial role of annotations in CPath projects, there are no well‐defined guidelines or best practices on how annotations should be carried out. In this paper, we address this shortcoming by presenting the experience and best practices acquired during the execution of a large‐scale annotation exercise involving a multidisciplinary team of pathologists, ML experts, and researchers as part of the Pathology image data Lake for Analytics, Knowledge and Education (PathLAKE) consortium. We present a real‐world case study along with examples of different types of annotations, diagnostic algorithm, annotation data dictionary, and annotation constructs. The analyses reported in this work highlight best practice recommendations that can be used as annotation guidelines over the lifecycle of a CPath project.
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Affiliation(s)
- Noorul Wahab
- Tissue Image Analytics Centre, University of Warwick, Coventry, UK
| | - Islam M Miligy
- Pathology, University of Nottingham, Nottingham, UK.,Department of Pathology, Faculty of Medicine, Menoufia University, Shebin El-Kom, Egypt
| | - Katherine Dodd
- Histopathology, University Hospital Coventry and Warwickshire, Coventry, UK
| | - Harvir Sahota
- Histopathology, University Hospital Coventry and Warwickshire, Coventry, UK
| | - Michael Toss
- Pathology, University of Nottingham, Nottingham, UK
| | - Wenqi Lu
- Tissue Image Analytics Centre, University of Warwick, Coventry, UK
| | | | - Mohsin Bilal
- Tissue Image Analytics Centre, University of Warwick, Coventry, UK
| | - Simon Graham
- Tissue Image Analytics Centre, University of Warwick, Coventry, UK
| | - Young Park
- Tissue Image Analytics Centre, University of Warwick, Coventry, UK
| | | | - Abhir Bhalerao
- Tissue Image Analytics Centre, University of Warwick, Coventry, UK
| | | | | | - Ayaka Katayama
- Graduate School of Medicine, Gunma University, Maebashi, Japan
| | | | | | - Tom Sorell
- Department of Politics and International Studies, University of Warwick, Coventry, UK
| | | | - Emily Hero
- Histopathology, University Hospital Coventry and Warwickshire, Coventry, UK.,Leicester Royal Infirmary, Histopathology, University Hospitals Leicester, Leicester, UK
| | - Hesham Eldaly
- Histopathology, University Hospital Coventry and Warwickshire, Coventry, UK
| | - Yee Wah Tsang
- Histopathology, University Hospital Coventry and Warwickshire, Coventry, UK
| | | | - David Snead
- Histopathology, University Hospital Coventry and Warwickshire, Coventry, UK
| | - Emad Rakha
- Pathology, University of Nottingham, Nottingham, UK
| | - Nasir Rajpoot
- Tissue Image Analytics Centre, University of Warwick, Coventry, UK
| | - Fayyaz Minhas
- Tissue Image Analytics Centre, University of Warwick, Coventry, UK
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5
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Awan R, Benes K, Azam A, Song TH, Shaban M, Verrill C, Tsang YW, Snead D, Minhas F, Rajpoot N. Deep learning based digital cell profiles for risk stratification of urine cytology images. Cytometry A 2021; 99:732-742. [PMID: 33486882 DOI: 10.1002/cyto.a.24313] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 12/05/2020] [Accepted: 12/15/2020] [Indexed: 11/06/2022]
Abstract
Urine cytology is a test for the detection of high-grade bladder cancer. In clinical practice, the pathologist would manually scan the sample under the microscope to locate atypical and malignant cells. They would assess the morphology of these cells to make a diagnosis. Accurate identification of atypical and malignant cells in urine cytology is a challenging task and is an essential part of identifying different diagnosis with low-risk and high-risk malignancy. Computer-assisted identification of malignancy in urine cytology can be complementary to the clinicians for treatment management and in providing advice for carrying out further tests. In this study, we presented a method for identifying atypical and malignant cells followed by their profiling to predict the risk of diagnosis automatically. For cell detection and classification, we employed two different deep learning-based approaches. Based on the best performing network predictions at the cell level, we identified low-risk and high-risk cases using the count of atypical cells and the total count of atypical and malignant cells. The area under the receiver operating characteristic (ROC) curve shows that a total count of atypical and malignant cells is comparably better at diagnosis as compared to the count of malignant cells only. We obtained area under the ROC curve with the count of malignant cells and the total count of atypical and malignant cells as 0.81 and 0.83, respectively. Our experiments also demonstrate that the digital risk could be a better predictor of the final histopathology-based diagnosis. We also analyzed the variability in annotations at both cell and whole slide image level and also explored the possible inherent rationales behind this variability.
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Affiliation(s)
- Ruqayya Awan
- Department of Computer Science, University of Warwick, Coventry, UK
| | - Ksenija Benes
- The Royal Wolverhampton NHS Trust, Wolverhampton, UK
| | - Ayesha Azam
- Department of Computer Science, University of Warwick, Coventry, UK.,Department of Pathology, University Hospitals Coventry and Warwickshire, Coventry, UK
| | - Tzu-Hsi Song
- Department of Computer Science, University of Warwick, Coventry, UK.,Laboratory of Quantitative Cellular Imaging, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | - Muhammad Shaban
- Department of Computer Science, University of Warwick, Coventry, UK
| | - Clare Verrill
- Nuffield Department of Surgical Sciences and Oxford NIHR Biomedical Research Centre, University of Oxford, Oxford, UK
| | - Yee Wah Tsang
- Department of Pathology, University Hospitals Coventry and Warwickshire, Coventry, UK
| | - David Snead
- Department of Pathology, University Hospitals Coventry and Warwickshire, Coventry, UK
| | - Fayyaz Minhas
- Department of Computer Science, University of Warwick, Coventry, UK
| | - Nasir Rajpoot
- Department of Computer Science, University of Warwick, Coventry, UK.,Department of Pathology, University Hospitals Coventry and Warwickshire, Coventry, UK.,The Alan Turing Institute, London, UK
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6
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Molloy K, Tsang YW, Shim TN. Not another genital wart? Clin Exp Dermatol 2020; 45:635-637. [PMID: 31900945 DOI: 10.1111/ced.14159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 11/09/2019] [Accepted: 11/26/2019] [Indexed: 11/27/2022]
Affiliation(s)
- K Molloy
- Department of, Dermatology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Y W Tsang
- Department of, Pathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - T N Shim
- Department of, Dermatology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
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7
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Graham S, Vu QD, Raza SEA, Azam A, Tsang YW, Kwak JT, Rajpoot N. Hover-Net: Simultaneous segmentation and classification of nuclei in multi-tissue histology images. Med Image Anal 2019; 58:101563. [PMID: 31561183 DOI: 10.1016/j.media.2019.101563] [Citation(s) in RCA: 305] [Impact Index Per Article: 61.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 09/04/2019] [Accepted: 09/16/2019] [Indexed: 12/21/2022]
Abstract
Nuclear segmentation and classification within Haematoxylin & Eosin stained histology images is a fundamental prerequisite in the digital pathology work-flow. The development of automated methods for nuclear segmentation and classification enables the quantitative analysis of tens of thousands of nuclei within a whole-slide pathology image, opening up possibilities of further analysis of large-scale nuclear morphometry. However, automated nuclear segmentation and classification is faced with a major challenge in that there are several different types of nuclei, some of them exhibiting large intra-class variability such as the nuclei of tumour cells. Additionally, some of the nuclei are often clustered together. To address these challenges, we present a novel convolutional neural network for simultaneous nuclear segmentation and classification that leverages the instance-rich information encoded within the vertical and horizontal distances of nuclear pixels to their centres of mass. These distances are then utilised to separate clustered nuclei, resulting in an accurate segmentation, particularly in areas with overlapping instances. Then, for each segmented instance the network predicts the type of nucleus via a devoted up-sampling branch. We demonstrate state-of-the-art performance compared to other methods on multiple independent multi-tissue histology image datasets. As part of this work, we introduce a new dataset of Haematoxylin & Eosin stained colorectal adenocarcinoma image tiles, containing 24,319 exhaustively annotated nuclei with associated class labels.
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Affiliation(s)
- Simon Graham
- Mathematics for Real World Systems Centre for Doctoral Training, University of Warwick, UK; Department of Computer Science, University of Warwick, UK.
| | - Quoc Dang Vu
- Department of Computer Science and Engineering, Sejong University, South Korea
| | - Shan E Ahmed Raza
- Department of Computer Science, University of Warwick, UK; Centre for Evolution and Cancer & Division of Molecular Pathology, The Institute of Cancer Research, London, UK
| | - Ayesha Azam
- Department of Computer Science, University of Warwick, UK; University Hospitals Coventry and Warwickshire, Coventry, UK
| | - Yee Wah Tsang
- University Hospitals Coventry and Warwickshire, Coventry, UK
| | - Jin Tae Kwak
- Department of Computer Science and Engineering, Sejong University, South Korea
| | - Nasir Rajpoot
- Department of Computer Science, University of Warwick, UK; The Alan Turing Institute, London, UK
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Graham S, Chen H, Gamper J, Dou Q, Heng PA, Snead D, Tsang YW, Rajpoot N. MILD-Net: Minimal information loss dilated network for gland instance segmentation in colon histology images. Med Image Anal 2018; 52:199-211. [PMID: 30594772 DOI: 10.1016/j.media.2018.12.001] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 12/04/2018] [Accepted: 12/14/2018] [Indexed: 02/08/2023]
Abstract
The analysis of glandular morphology within colon histopathology images is an important step in determining the grade of colon cancer. Despite the importance of this task, manual segmentation is laborious, time-consuming and can suffer from subjectivity among pathologists. The rise of computational pathology has led to the development of automated methods for gland segmentation that aim to overcome the challenges of manual segmentation. However, this task is non-trivial due to the large variability in glandular appearance and the difficulty in differentiating between certain glandular and non-glandular histological structures. Furthermore, a measure of uncertainty is essential for diagnostic decision making. To address these challenges, we propose a fully convolutional neural network that counters the loss of information caused by max-pooling by re-introducing the original image at multiple points within the network. We also use atrous spatial pyramid pooling with varying dilation rates for preserving the resolution and multi-level aggregation. To incorporate uncertainty, we introduce random transformations during test time for an enhanced segmentation result that simultaneously generates an uncertainty map, highlighting areas of ambiguity. We show that this map can be used to define a metric for disregarding predictions with high uncertainty. The proposed network achieves state-of-the-art performance on the GlaS challenge dataset and on a second independent colorectal adenocarcinoma dataset. In addition, we perform gland instance segmentation on whole-slide images from two further datasets to highlight the generalisability of our method. As an extension, we introduce MILD-Net+ for simultaneous gland and lumen segmentation, to increase the diagnostic power of the network.
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Affiliation(s)
- Simon Graham
- Mathematics for Real World Systems Centre for Doctoral Training, University of Warwick, Coventry, CV4 7AL, UK; Department of Computer Science, University of Warwick, UK.
| | - Hao Chen
- Department of Computer Science and Engineering, The Chinese University of Hong Kong, China
| | - Jevgenij Gamper
- Mathematics for Real World Systems Centre for Doctoral Training, University of Warwick, Coventry, CV4 7AL, UK; Department of Computer Science, University of Warwick, UK
| | - Qi Dou
- Department of Computer Science and Engineering, The Chinese University of Hong Kong, China
| | - Pheng-Ann Heng
- Department of Computer Science and Engineering, The Chinese University of Hong Kong, China
| | - David Snead
- Department of Pathology, University Hospitals Coventry and Warwickshire, Coventry, UK
| | - Yee Wah Tsang
- Department of Pathology, University Hospitals Coventry and Warwickshire, Coventry, UK
| | - Nasir Rajpoot
- Department of Computer Science, University of Warwick, UK; Department of Pathology, University Hospitals Coventry and Warwickshire, Coventry, UK; The Alan Turing Institute, London, UK
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Sirinukunwattana K, Snead D, Epstein D, Aftab Z, Mujeeb I, Tsang YW, Cree I, Rajpoot N. Novel digital signatures of tissue phenotypes for predicting distant metastasis in colorectal cancer. Sci Rep 2018; 8:13692. [PMID: 30209315 PMCID: PMC6135776 DOI: 10.1038/s41598-018-31799-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 08/07/2018] [Indexed: 12/18/2022] Open
Abstract
Distant metastasis is the major cause of death in colorectal cancer (CRC). Patients at high risk of developing distant metastasis could benefit from appropriate adjuvant and follow-up treatments if stratified accurately at an early stage of the disease. Studies have increasingly recognized the role of diverse cellular components within the tumor microenvironment in the development and progression of CRC tumors. In this paper, we show that automated analysis of digitized images from locally advanced colorectal cancer tissue slides can provide estimate of risk of distant metastasis on the basis of novel tissue phenotypic signatures of the tumor microenvironment. Specifically, we determine what cell types are found in the vicinity of other cell types, and in what numbers, rather than concentrating exclusively on the cancerous cells. We then extract novel tissue phenotypic signatures using statistical measurements about tissue composition. Such signatures can underpin clinical decisions about the advisability of various types of adjuvant therapy.
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Affiliation(s)
| | - David Snead
- Department of Pathology, University Hospitals Coventry and Warwickshire, Coventry, UK
| | - David Epstein
- Mathematics Institute, University of Warwick, Coventry, UK
| | - Zia Aftab
- Hamad Medical Corporation, Doha, Qatar
| | | | - Yee Wah Tsang
- Department of Pathology, University Hospitals Coventry and Warwickshire, Coventry, UK
| | - Ian Cree
- International Agency for Research on Cancer, Lyon, France
| | - Nasir Rajpoot
- Department of Pathology, University Hospitals Coventry and Warwickshire, Coventry, UK.
- Department of Computer Science, University of Warwick, Coventry, UK.
- The Alan Turing Institute, London, UK.
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10
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Lee ACW, Wai JWC, Cheung OY, Chiu LF, Tsang YW, Tsang HHC, Fok WS, Wong HN, Sitt JCM, Cheng SS, Chiang JB, Tsang KW. Mucinous Carcinoma of the Breast: Imaging Features and Pathological Correlation. Hong Kong J Radiol 2018. [DOI: 10.12809/hkjr1616821] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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11
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Reiman A, Kikuchi H, Scocchia D, Smith P, Tsang YW, Snead D, Cree IA. Validation of an NGS mutation detection panel for melanoma. BMC Cancer 2017; 17:150. [PMID: 28228113 PMCID: PMC5322598 DOI: 10.1186/s12885-017-3149-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Accepted: 02/18/2017] [Indexed: 11/10/2022] Open
Abstract
Background Knowledge of the genotype of melanoma is important to guide patient management. Identification of mutations in BRAF and c-KIT lead directly to targeted treatment, but it is also helpful to know if there are driver oncogene mutations in NRAS, GNAQ or GNA11 as these patients may benefit from alternative strategies such as immunotherapy. Methods While polymerase chain reaction (PCR) methods are often used to detect BRAF mutations, next generation sequencing (NGS) is able to determine all of the necessary information on several genes at once, with potential advantages in turnaround time. We describe here an Ampliseq hotspot panel for melanoma for use with the IonTorrent Personal Genome Machine (PGM) which covers the mutations currently of most clinical interest. Results We have validated this in 151 cases of skin and uveal melanoma from our files, and correlated the data with PCR based assessment of BRAF status. There was excellent agreement, with few discrepancies, though NGS does have greater coverage and picks up some mutations that would be missed by PCR. However, these are often rare and of unknown significance for treatment. Conclusions PCR methods are rapid, less time-consuming and less expensive than NGS, and could be used as triage for patients requiring more extensive diagnostic workup. The NGS panel described here is suitable for clinical use with formalin-fixed paraffin-embedded (FFPE) samples. Electronic supplementary material The online version of this article (doi:10.1186/s12885-017-3149-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Anne Reiman
- Department of Pathology - Coventry and Warwickshire Pathology Services (CWPS), University Hospitals Coventry and Warwickshire, Coventry, CV2 2DX, UK.,Centre for Research in Applied Biological and Exercise Sciences, Coventry University, Coventry, CV1 5FB, UK
| | - Hugh Kikuchi
- Department of Pathology - Coventry and Warwickshire Pathology Services (CWPS), University Hospitals Coventry and Warwickshire, Coventry, CV2 2DX, UK.,Centre for Research in Applied Biological and Exercise Sciences, Coventry University, Coventry, CV1 5FB, UK
| | - Daniela Scocchia
- Department of Pathology - Coventry and Warwickshire Pathology Services (CWPS), University Hospitals Coventry and Warwickshire, Coventry, CV2 2DX, UK
| | - Peter Smith
- Department of Pathology - Coventry and Warwickshire Pathology Services (CWPS), University Hospitals Coventry and Warwickshire, Coventry, CV2 2DX, UK
| | - Yee Wah Tsang
- Department of Pathology - Coventry and Warwickshire Pathology Services (CWPS), University Hospitals Coventry and Warwickshire, Coventry, CV2 2DX, UK
| | - David Snead
- Department of Pathology - Coventry and Warwickshire Pathology Services (CWPS), University Hospitals Coventry and Warwickshire, Coventry, CV2 2DX, UK
| | - Ian A Cree
- Department of Pathology - Coventry and Warwickshire Pathology Services (CWPS), University Hospitals Coventry and Warwickshire, Coventry, CV2 2DX, UK. .,Institute of Ophthalmology, University College London, Bath Street, London, EC1V 9EL, UK. .,Centre for Technology Enabled Health Research (CTEHR), Faculty of Health & Life Sciences, Coventry University, Coventry, CV1 5FB, UK.
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12
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Trahearn N, Tsang YW, Cree IA, Snead D, Epstein D, Rajpoot N. Simultaneous automatic scoring and co-registration of hormone receptors in tumor areas in whole slide images of breast cancer tissue slides. Cytometry A 2016; 91:585-594. [PMID: 28009468 DOI: 10.1002/cyto.a.23035] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 09/26/2016] [Accepted: 11/21/2016] [Indexed: 01/16/2023]
Abstract
Automation of downstream analysis may offer many potential benefits to routine histopathology. One area of interest for automation is in the scoring of multiple immunohistochemical markers to predict the patient's response to targeted therapies. Automated serial slide analysis of this kind requires robust registration to identify common tissue regions across sections. We present an automated method for co-localized scoring of Estrogen Receptor and Progesterone Receptor (ER/PR) in breast cancer core biopsies using whole slide images. Regions of tumor in a series of fifty consecutive breast core biopsies were identified by annotation on H&E whole slide images. Sequentially cut immunohistochemical stained sections were scored manually, before being digitally scanned and then exported into JPEG 2000 format. A two-stage registration process was performed to identify the annotated regions of interest in the immunohistochemistry sections, which were then scored using the Allred system. Overall correlation between manual and automated scoring for ER and PR was 0.944 and 0.883, respectively, with 90% of ER and 80% of PR scores within in one point or less of agreement. This proof of principle study indicates slide registration can be used as a basis for automation of the downstream analysis for clinically relevant biomarkers in the majority of cases. The approach is likely to be improved by implantation of safeguarding analysis steps post registration. © 2016 International Society for Advancement of Cytometry.
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Affiliation(s)
- Nicholas Trahearn
- Department of Computer Science, University of Warwick, Coventry, United Kingdom
| | - Yee Wah Tsang
- Department of Pathology, University of Warwick, Coventry, United Kingdom.,Centre of Excellence for Digital Pathology, University Hospitals Coventry and Warwickshire, Coventry, United Kingdom
| | - Ian A Cree
- Centre of Excellence for Digital Pathology, University Hospitals Coventry and Warwickshire, Coventry, United Kingdom
| | - David Snead
- Department of Pathology, University of Warwick, Coventry, United Kingdom.,Centre of Excellence for Digital Pathology, University Hospitals Coventry and Warwickshire, Coventry, United Kingdom
| | - David Epstein
- Mathematics Institute, University of Warwick, Coventry, United Kingdom
| | - Nasir Rajpoot
- Department of Computer Science, University of Warwick, Coventry, United Kingdom.,Centre of Excellence for Digital Pathology, University Hospitals Coventry and Warwickshire, Coventry, United Kingdom
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13
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Adab P, Jiang CQ, Rankin E, Tsang YW, Lam TH, Barlow J, Thomas GN, Zhang WS, Cheng KK. Breastfeeding practice, oral contraceptive use and risk of rheumatoid arthritis among Chinese women: the Guangzhou Biobank Cohort Study. Rheumatology (Oxford) 2014; 53:860-6. [PMID: 24395920 DOI: 10.1093/rheumatology/ket456] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVE Hormonal and reproductive factors are implicated in the aetiology of RA, but results of previous studies have been mixed. The aim of this cross-sectional study was to assess the relationships between RA, use of oral contraceptives (OCs) and history of breastfeeding in a population of older women from South China. METHODS We used baseline data from 7349 women ≥ 50 years of age in the Guangzhou Biobank Cohort. Questionnaires were used to obtain socio-demographic, lifestyle and obstetric history data, including parity, OC use and breastfeeding practices. The main outcome was RA. Women were asked about history of RA and were examined to assess joint swelling. RF levels were measured. The presence of RA was defined in two ways: (i) as reporting physician-diagnosed RA or pain and swelling in at least three joints (including the wrist), and (ii) also having at least one of the following: positive RF, morning stiffness or objective swelling of the small joints of the hands. RESULTS Compared with those who had never breastfed, breastfeeding was associated with half the risk of RA. The risk was lower with increasing duration of breastfeeding [adjusted odds ratio (OR) 0.54 (95% CI 0.29, 1.01) for breastfeeding at least 36 months; P for trend = 0.04]. OC use had no relationship with RA. CONCLUSION Breastfeeding (especially longer duration) but not OC use is associated with a lower risk of RA. This has potentially important implications for future RA disease burden, given the declining rates of breastfeeding and the one-child policy in China. Further research is needed to explain the biological mechanism.
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Affiliation(s)
- Peymane Adab
- Department of Rheumatology, University Hospital Birmingham, Mindelsohn Way, Edgbaston, Birmingham B15 2WB, UK.
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14
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Shim TN, Tsang YW, Snead D, Ilchyshyn A. A scaly plaque on the left buttock. Clin Exp Dermatol 2012; 38:324-6. [PMID: 23083135 DOI: 10.1111/j.1365-2230.2012.04466.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- T N Shim
- Department of Dermatology, University Hospitals Coventry and Warwickshire NHS Trust, UK.
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15
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Tsang YW, Brown L, Parker S. The Value of Taking Non-Sentinel Lymph Nodes During the Sentinal Node Procedure? Eur J Surg Oncol 2011. [DOI: 10.1016/j.ejso.2011.08.050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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16
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Mukhopadhyay S, Tsang YW. Uncertainties in coupled thermal-hydrological processes associated with the Drift Scale Test at Yucca Mountain, Nevada. J Contam Hydrol 2003; 62-63:595-612. [PMID: 12714312 DOI: 10.1016/s0169-7722(02)00186-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Understanding thermally driven coupled hydrological, mechanical, and chemical processes in unsaturated fractured tuff is essential for evaluating the performance of the potential radioactive waste repository at Yucca Mountain, Nevada. The Drift Scale Test (DST), intended for acquiring such an understanding of these processes, has generated a huge volume of temperature and moisture redistribution data. Sophisticated thermal-hydrological (TH) conceptual models have yielded a good fit between simulation results and those measured data. However, some uncertainties in understanding the TH processes associated with the DST still exist. This paper evaluates these uncertainties and provides quantitative estimates of the range of these uncertainties. Of particular interest for the DST are the uncertainties resulting from the unmonitored loss of vapor through an open bulkhead of the test. There was concern that the outcome from the test might have been significantly altered by these losses. Using alternative conceptual models, we illustrate that predicted mean temperatures from the DST are within 1 degrees C of the measured mean temperatures through the first 2 years of heating. The simulated spatial and temporal evolution of drying and condensation fronts is found to be qualitatively consistent with measured saturation data. Energy and mass balance computation shows that no more than 13% of the input energy is lost because of vapor leaving the test domain through the bulkhead. The change in average saturation in fractures is also relatively small. For a hypothetical situation in which no vapor is allowed to exit through the bulkhead, the simulated average fracture saturation is not qualitatively different enough to be discerned by measured moisture redistribution data. This leads us to conclude that the DST, despite the uncertainties associated with open field testing, has provided an excellent understanding of the TH processes.
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Affiliation(s)
- S Mukhopadhyay
- Earth Sciences Division, E.O. Lawrence Berkeley National Laboratory, CA 94720, USA.
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17
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Mak YK, Chan CH, Li CKP, Lee MP, Tsang YW. Clinical profiles of human immunodeficiency virus-associated lymphoma in Hong Kong. Hong Kong Med J 2003; 9:91-7. [PMID: 12668818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023] Open
Abstract
OBJECTIVE To identify the clinical and prognostic features of human immunodeficiency virus-associated lymphoma in the local population with a view to designing more effective treatment strategies. DESIGN Retrospective review. SETTING Referral hospital, Hong Kong. SUBJECTS AND METHODS All patients (n=10) with human immunodeficiency virus-associated lymphoma managed at Queen Elizabeth Hospital from January 1995 to December 2001. RESULTS All patients were men with a median age of 39 years. The median CD4 cell count at the time of diagnosis of lymphoma was 0.056 x 10(9)/L. All tumours were diffuse large B-cell lymphomas, with the exception of one systemic Burkittlike lymphoma. Systemic lymphoma was diagnosed in seven patients and three had primary central nervous system lymphoma. Combined antiretroviral therapy was continued or given to five of the six patients who received some form of chemotherapy or radiotherapy treatment. Of the two patients with primary central nervous system lymphoma who received whole brain irradiation therapy, one patient survived 41 months in clinical remission after diagnosis and the other patient died of sepsis while in partial remission 19 months after diagnosis. The four patients with systemic lymphoma who received standard- or reduced-dose chemotherapy with cyclophosphamide, doxorubicin, vincristine, and prednisone had a median survival of 3 months. CONCLUSION The clinical profiles of these patients were similar to those of patients with human immunodeficiency virus-associated lymphoma in western countries. The overall survival of patients was poor with conventional chemoradiotherapy. Other innovative treatment approaches should be investigated to prolong the survival of this patient group.
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MESH Headings
- Adolescent
- Adult
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Antiretroviral Therapy, Highly Active
- Burkitt Lymphoma/diagnosis
- Burkitt Lymphoma/therapy
- Central Nervous System Neoplasms/diagnosis
- Central Nervous System Neoplasms/pathology
- Central Nervous System Neoplasms/therapy
- Cyclophosphamide/therapeutic use
- Doxorubicin/therapeutic use
- Hemoglobins/analysis
- Herpesvirus 4, Human/isolation & purification
- Hong Kong
- Humans
- L-Lactate Dehydrogenase/blood
- Lymphoma, AIDS-Related/diagnosis
- Lymphoma, AIDS-Related/pathology
- Lymphoma, AIDS-Related/therapy
- Lymphoma, Large B-Cell, Diffuse/diagnosis
- Lymphoma, Large B-Cell, Diffuse/pathology
- Lymphoma, Large B-Cell, Diffuse/therapy
- Male
- Middle Aged
- Neoplasm Metastasis
- Platelet Count
- Prednisone/therapeutic use
- RNA, Viral/analysis
- Reference Values
- Retrospective Studies
- Risk Factors
- Treatment Outcome
- Vincristine/therapeutic use
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Affiliation(s)
- Y K Mak
- Department of Medicine, Queen Elizabeth Hospital, 30 Gascoigne Road, Kowloon, Hong Kong
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18
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Haukwa CB, Tsang YW, Wu YS, Bodvarsson GS. Effect of heterogeneity in fracture permeability on the potential for liquid seepage into a heated emplacement drift of the potential repository. J Contam Hydrol 2003; 62-63:509-527. [PMID: 12714308 DOI: 10.1016/s0169-7722(02)00152-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A numerical model was used to investigate the effect of spatial variability in fracture permeability on liquid seepage and moisture distribution in the vicinity of a waste emplacement drift in the unsaturated zone (UZ) of Yucca Mountain. The model is based on a two-dimensional, cross-sectional, dual-permeability model of the unsaturated zone at Yucca Mountain and uses a stochastic approach to investigate the effect of small-scale heterogeneous features. The studies were conducted using one uniform fracture permeability case, three realizations of stochastically generated fracture permeability, one discrete permeability feature case, and one increased ambient liquid flux case. In all cases, the models predict that completely dry drift conditions will develop above and below the drift in 10-100 years and remain dry for 1000-2000 years. During this period, the models predict no seepage into drifts, although liquid flux above the drifts and within the drift pillars may increase by up to two orders of magnitude above ambient flux. This is because the heat released by the emplaced waste is sufficient to vaporize liquid flux of one to two orders of magnitude higher than present-day ambient flux for over 1000 years. The results also show that unsaturated zone thermal-hydrological (TH) models with uniform layer permeability can adequately predict the evolution of seepage and moisture distribution in the rock mass surrounding the repository drifts. The models further show that although variability in fracture permeability may focus and enhance liquid flow in regions of enhanced liquid saturation (due to condensation above the drifts), vaporization and vapor diffusion can maintain a dry environment within the drifts for thousands of years.
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Affiliation(s)
- C B Haukwa
- Earth Sciences Division, Lawrence Berkeley National Laboratory, CA 94720, USA.
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Chi KH, Myers JN, Chow KC, Chan WK, Tsang YW, Chao Y, Yen SH, Lotze MT. Phase II trial of systemic recombinant interleukin-2 in the treatment of refractory nasopharyngeal carcinoma. Oncology 2001; 60:110-5. [PMID: 11244324 DOI: 10.1159/000055306] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Interleukin-2 (IL-2) is a cytokine produced by activated T cells, which has shown powerful immunostimulatory and antineoplastic properties. Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus-associated cancer with abundant lymphocyte infiltration histologically. The activity of IL-2 in the treatment of NPC patients is currently unknown. A phase II study was, therefore, initiated to evaluate the efficacy, toxicity and immunological consequences of intravenous bolus IL-2 in patients with recurrent/metastatic NPC. METHODS Between November 1996 and April 1997, 14 patients with recurrent/metastatic NPC were entered into the study. Recombinant IL-2 (Proleukin, Chiron) was injected by intravenous bolus every 8 h at 72,000 IU/kg for a maximum of 15 doses. After 7 days, patients were retreated with a second identical cycle of therapy. Those patients who were stable or responding to treatment 5-6 weeks later went on to receive another course (two cycles) of therapy. All patients received prophylactic antibiotics and antipyretic medicine. Response and toxicities were evaluated. Serial plasma level of TNF-alpha, IL-6, soluble IL-2 receptor, IL-10 and soluble CD8 were determined. RESULTS Fourteen patients received a total of 34 cycles of therapy. No response was observed. Fifty percent had stable disease, 50% had progressive disease after a median of two cycles of therapy. There was one treatment-related death from acute myocardial infarction. Body weight increase (>5%) occurred in 80% of cycles, and hypotension (BP <80 mm Hg systolic) occurred in 53%. Serum creatinine increase (>2 mg%) occurred in 24% of cycles, and SGOT/SGPT increase (>3x) in 10% of cycles. Symptoms of somnolence, general malaise, nausea and vomiting, pruritus, xerostomia, desquamation were generally mild to moderate but rapidly reversible. CONCLUSION The single modality of intravenous bolus IL-2 at the dose level of 72,000 IU/kg is clinically ineffective in NPC patients. Potential mechanisms of the ineffectiveness of IL-2 therapy on NPC patients are discussed.
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Affiliation(s)
- K H Chi
- Cancer Center, Veterans General Hospital-Taipei, National Yang-Ming University, Taipei, Taiwan, ROC.
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Cheng KM, Chan CM, Fu YT, Ho LC, Tsang YW, Lee MK, Cheung YL, Law CK. Brain abscess formation in radiation necrosis of the temporal lobe following radiation therapy for nasopharyngeal carcinoma. Acta Neurochir (Wien) 2001; 142:435-40; discussion 440-1. [PMID: 10883341 DOI: 10.1007/s007010050454] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND Radiation necrosis is a known complication following radiation therapy for extracranial as well as intracranial tumours. However, brain abscess formation in radiation necrosis has not been reported in the literature. We report the clinical data of 6 patients suffering from this condition. METHOD Twenty-eight patients with radiation necrosis of the temporal lobe following radiotherapy for nasopharyngeal carcinoma were treated surgically at the Department of Neurosurgery, Queen Elizabeth Hospital, Hong Kong between January 1992 and July 1999. Of these, 6 cases were complicated by brain abscess formation. The clinical data of these 6 patients are retrospectively reviewed. FINDINGS The patients were 5 males and 1 female, ranging in age from 41 to 67 years. Three patients had previous treatment with steroids for the symptomatic radiation necrosis. A history of nasal infection or otitis media was recognised in all 6 patients. All patients were treated surgically by temporal lobectomy and excision of the necrotic tissue together with the abscess cavity. Intra-operatively, a bony defect was observed between the middle cranial fossa and the sphenoid sinus in 3 patients and the bony defect was repaired with a temporalis muscle flap. The species of organisms could only be identified in 3 patients. In 3 patients, the pus smear was positive but the culture was negative. Subsequently, 4 patients recovered and 2 patients died. INTERPRETATION Cerebral radiation necrosis is a predisposing cause of brain abscess formation. Surgical excision is recommended as the treatment of choice in this group of patients.
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Affiliation(s)
- K M Cheng
- Department of Neurosurgery, Queen Elizabeth Hospital, Hong Kong, China
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22
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Abstract
We report a case of polymorphous low grade adenocarcinoma involving the palate of a 12-year-old girl, the first example of this tumour occurring in the paediatric age group. The tumour displayed infiltrative growth, neural invasion, variegated histological patterns, and minimal cytological atypia. The patient remained disease-free four years after wide local excision of the tumour. The distinction of polymorphous low grade adenocarcinoma from pleomorphic adenoma and adenoid cystic carcinoma is also discussed.
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Affiliation(s)
- Y W Tsang
- Institute of Pathology, Queen Elizabeth Hospital, Hong Kong
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Abstract
Mucous glands carcinomas of the larynx are rare, with most being represented by 'non-specific' adenocarcinoma and adenoid cystic carcinoma. Here we report a unique case of mucoid adenocarcinoma of the larynx occurring in a 46-year-old woman. Despite the presence of regional lymph node metastasis, she remained well four years after surgery.
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Affiliation(s)
- Y W Tsang
- Institute of Pathology, Queen Elizabeth Hospital, Kowloon, Hong Kong
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