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Sample records for brain tumour classification

  1. Brain tumour classification and abnormality detection using neuro-fuzzy technique and Otsu thresholding.

    PubMed

    Renjith, Arokia; Manjula, P; Mohan Kumar, P

    2015-01-01

    Brain tumour is one of the main causes for an increase in transience among children and adults. This paper proposes an improved method based on Magnetic Resonance Imaging (MRI) brain image classification and image segmentation approach. Automated classification is encouraged by the need of high accuracy when dealing with a human life. The detection of the brain tumour is a challenging problem, due to high diversity in tumour appearance and ambiguous tumour boundaries. MRI images are chosen for detection of brain tumours, as they are used in soft tissue determinations. First of all, image pre-processing is used to enhance the image quality. Second, dual-tree complex wavelet transform multi-scale decomposition is used to analyse texture of an image. Feature extraction extracts features from an image using gray-level co-occurrence matrix (GLCM). Then, the Neuro-Fuzzy technique is used to classify the stages of brain tumour as benign, malignant or normal based on texture features. Finally, tumour location is detected using Otsu thresholding. The classifier performance is evaluated based on classification accuracies. The simulated results show that the proposed classifier provides better accuracy than previous method. PMID:26493726

  2. Three-dimensional textural features of conventional MRI improve diagnostic classification of childhood brain tumours.

    PubMed

    Fetit, Ahmed E; Novak, Jan; Peet, Andrew C; Arvanitits, Theodoros N

    2015-09-01

    The aim of this study was to assess the efficacy of three-dimensional texture analysis (3D TA) of conventional MR images for the classification of childhood brain tumours in a quantitative manner. The dataset comprised pre-contrast T1 - and T2-weighted MRI series obtained from 48 children diagnosed with brain tumours (medulloblastoma, pilocytic astrocytoma and ependymoma). 3D and 2D TA were carried out on the images using first-, second- and higher order statistical methods. Six supervised classification algorithms were trained with the most influential 3D and 2D textural features, and their performances in the classification of tumour types, using the two feature sets, were compared. Model validation was carried out using the leave-one-out cross-validation (LOOCV) approach, as well as stratified 10-fold cross-validation, in order to provide additional reassurance. McNemar's test was used to test the statistical significance of any improvements demonstrated by 3D-trained classifiers. Supervised learning models trained with 3D textural features showed improved classification performances to those trained with conventional 2D features. For instance, a neural network classifier showed 12% improvement in area under the receiver operator characteristics curve (AUC) and 19% in overall classification accuracy. These improvements were statistically significant for four of the tested classifiers, as per McNemar's tests. This study shows that 3D textural features extracted from conventional T1 - and T2-weighted images can improve the diagnostic classification of childhood brain tumours. Long-term benefits of accurate, yet non-invasive, diagnostic aids include a reduction in surgical procedures, improvement in surgical and therapy planning, and support of discussions with patients' families. It remains necessary, however, to extend the analysis to a multicentre cohort in order to assess the scalability of the techniques used. PMID:26256809

  3. Classification of brain tumours from MR spectra: the INTERPRET collaboration and its outcomes.

    PubMed

    Julià-Sapé, Margarida; Griffiths, John R; Tate, Rosemary A; Howe, Franklyn A; Acosta, Dionisio; Postma, Geert; Underwood, Joshua; Majós, Carles; Arús, Carles

    2015-12-01

    The INTERPRET project was a multicentre European collaboration, carried out from 2000 to 2002, which developed a decision-support system (DSS) for helping neuroradiologists with no experience of MRS to utilize spectroscopic data for the diagnosis and grading of human brain tumours. INTERPRET gathered a large collection of MR spectra of brain tumours and pseudo-tumoural lesions from seven centres. Consensus acquisition protocols, a standard processing pipeline and strict methods for quality control of the aquired data were put in place. Particular emphasis was placed on ensuring the diagnostic certainty of each case, for which all cases were evaluated by a clinical data validation committee. One outcome of the project is a database of 304 fully validated spectra from brain tumours, pseudotumoural lesions and normal brains, along with their associated images and clinical data, which remains available to the scientific and medical community. The second is the INTERPRET DSS, which has continued to be developed and clinically evaluated since the project ended. We also review here the results of the post-INTERPRET period. We evaluate the results of the studies with the INTERPRET database by other consortia or research groups. A summary of the clinical evaluations that have been performed on the post-INTERPRET DSS versions is also presented. Several have shown that diagnostic certainty can be improved for certain tumour types when the INTERPRET DSS is used in conjunction with conventional radiological image interpretation. About 30 papers concerned with the INTERPRET single-voxel dataset have so far been published. We discuss stengths and weaknesses of the DSS and the lessons learned. Finally we speculate on how the INTERPRET concept might be carried into the future. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26768492

  4. The use of multivariate MR imaging intensities versus metabolic data from MR spectroscopic imaging for brain tumour classification

    NASA Astrophysics Data System (ADS)

    Devos, A.; Simonetti, A. W.; van der Graaf, M.; Lukas, L.; Suykens, J. A. K.; Vanhamme, L.; Buydens, L. M. C.; Heerschap, A.; Van Huffel, S.

    2005-04-01

    This study investigated the value of information from both magnetic resonance imaging and magnetic resonance spectroscopic imaging (MRSI) to automated discrimination of brain tumours. The influence of imaging intensities and metabolic data was tested by comparing the use of MR spectra from MRSI, MR imaging intensities, peak integration values obtained from the MR spectra and a combination of the latter two. Three classification techniques were objectively compared: linear discriminant analysis, least squares support vector machines (LS-SVM) with a linear kernel as linear techniques and LS-SVM with radial basis function kernel as a nonlinear technique. Classifiers were evaluated over 100 stratified random splittings of the dataset into training and test sets. The area under the receiver operating characteristic (ROC) curve (AUC) was used as a global performance measure on test data. In general, all techniques obtained a high performance when using peak integration values with or without MR imaging intensities. For example for low- versus high-grade tumours, low- versus high-grade gliomas and gliomas versus meningiomas, the mean test AUC was higher than 0.91, 0.94, and 0.99, respectively, when both MR imaging intensities and peak integration values were used. The use of metabolic data from MRSI significantly improved automated classification of brain tumour types compared to the use of MR imaging intensities solely.

  5. Multicentre evaluation of the INTERPRET decision support system 2.0 for brain tumour classification.

    PubMed

    Julià-Sapé, Margarida; Majós, Carles; Camins, Àngels; Samitier, Alejandro; Baquero, Miguel; Serrallonga, Marta; Doménech, Sira; Grivé, Elisenda; Howe, Franklyn A; Opstad, Kirstie; Calvar, Jorge; Aguilera, Carles; Arús, Carles

    2014-09-01

    In a previous study, we have shown the added value of (1) H MRS for the neuroradiological characterisation of adult human brain tumours. In that study, several methods of MRS analysis were used, and a software program, the International Network for Pattern Recognition of Tumours Using Magnetic Resonance Decision Support System 1.0 (INTERPRET DSS 1.0), with a short-TE classifier, provided the best results. Since then, the DSS evolved into a version 2.0 that contains an additional long-TE classifier. This study has two objectives. First, to determine whether clinicians with no experience of spectroscopy are comparable with spectroscopists in the use of the system, when only minimum training in the use of the system was given. Second, to assess whether or not a version with another TE is better than the initial version. We undertook a second study with the same cases and nine evaluators to assess whether the diagnostic accuracy of DSS 2.0 was comparable with the values obtained with DSS 1.0. In the second study, the analysis protocol was flexible in comparison with the first one to mimic a clinical environment. In the present study, on average, each case required 5.4?min by neuroradiologists and 9?min by spectroscopists for evaluation. Most classes and superclasses of tumours gave the same results as with DSS 1.0, except for astrocytomas of World Health Organization (WHO) grade III, in which performance measured as the area under the curve (AUC) decreased: AUC?=?0.87 (0.72-1.02) with DSS 1.0 and AUC?=?0.62 (0.55-0.70) with DSS 2.0. When analysing the performance of radiologists and spectroscopists with respect to DSS 1.0, the results were the same for most classes. Having data with two TEs instead of one did not affect the results of the evaluation. PMID:25042391

  6. A multiresolution clinical decision support system based on fractal model design for classification of histological brain tumours.

    PubMed

    Al-Kadi, Omar S

    2015-04-01

    Tissue texture is known to exhibit a heterogeneous or non-stationary nature; therefore using a single resolution approach for optimum classification might not suffice. A clinical decision support system that exploits the subbands' textural fractal characteristics for best bases selection of meningioma brain histopathological image classification is proposed. Each subband is analysed using its fractal dimension instead of energy, which has the advantage of being less sensitive to image intensity and abrupt changes in tissue texture. The most significant subband that best identifies texture discontinuities will be chosen for further decomposition, and its fractal characteristics would represent the optimal feature vector for classification. The performance was tested using the support vector machine (SVM), Bayesian and k-nearest neighbour (kNN) classifiers and a leave-one-patient-out method was employed for validation. Our method outperformed the classical energy based selection approaches, achieving for SVM, Bayesian and kNN classifiers an overall classification accuracy of 94.12%, 92.50% and 79.70%, as compared to 86.31%, 83.19% and 51.63% for the co-occurrence matrix, and 76.01%, 73.50% and 50.69% for the energy texture signatures; respectively. These results indicate the potential usefulness as a decision support system that could complement radiologists' diagnostic capability to discriminate higher order statistical textural information; for which it would be otherwise difficult via ordinary human vision. PMID:24962336

  7. Brain tumour-associated status epilepticus.

    PubMed

    Goonawardena, Janindu; Marshman, Laurence A G; Drummond, Katharine J

    2015-01-01

    We have reviewed the scant literature on status epilepticus in patients with brain tumours. Patients with brain tumour-associated epilepsy (TAE) appear less likely to develop status epilepticus (TASE) than patients with epilepsy in the general population (EGP) are to develop status epilepticus (SEGP). TASE is associated with lesions in similar locations as TAE; in particular, the frontal lobes. However, in contrast to TAE, where seizures commence early in the course of the disease or at presentation, TASE is more likely to occur later in the disease course and herald tumour progression. In marked contrast to TAE, where epilepsy risk is inversely proportional to Word Health Organization tumour grade, TASE risk appears to be directly proportional to tumour grade (high grade gliomas appear singularly predisposed). Whilst anti-epileptic drug (AED) resistance is more common in TAE than EGP (with resistance directly proportional to tumour grade and frontal location), TASE appears paradoxically more responsive to simple AED regimes than either TAE or SEGP. Although some results suggest that mortality may be higher with TASE than with SEGP, it is likely that (as with SEGP) the major determinant of mortality is the underlying disease process. Because all such data have been derived from retrospective studies, because TASE and SEGP are less common than TAE and EGP, and because TASE and SEGP classification has often been inconsistent, findings can only be considered preliminary: multi-centre, prospective studies are required. Whilst preliminary, our review suggests that TASE has a distinct clinical profile compared to TAE and SEGP. PMID:25150762

  8. [Fourth edition of WHO classification tumours of soft tissue].

    PubMed

    Karanian, Marie; Coindre, Jean-Michel

    2015-01-01

    The new World Health Organization (WHO) classification of soft tissue tumours was published in 2013, 11years after the previous edition. This new classification includes several changes: newly included sections (gastrointestinal stromal tumors…), newly recognized entities (pseudomiogenic haemangioendothelioma, haemosiderotic fibrolipomatous tumour…), and new genetic and molecular data leading to better understanding and definition of tumours, and are useful as diagnostic tools. This brief review summarizes changes in this new edition of the WHO classification of tumours of soft tissue. PMID:25532684

  9. Phase congruency map driven brain tumour segmentation

    NASA Astrophysics Data System (ADS)

    Szilágyi, Tünde; Brady, Michael; Berényi, Ervin

    2015-03-01

    Computer Aided Diagnostic (CAD) systems are already of proven value in healthcare, especially for surgical planning, nevertheless much remains to be done. Gliomas are the most common brain tumours (70%) in adults, with a survival time of just 2-3 months if detected at WHO grades III or higher. Such tumours are extremely variable, necessitating multi-modal Magnetic Resonance Images (MRI). The use of Gadolinium-based contrast agents is only relevant at later stages of the disease where it highlights the enhancing rim of the tumour. Currently, there is no single accepted method that can be used as a reference. There are three main challenges with such images: to decide whether there is tumour present and is so localize it; to construct a mask that separates healthy and diseased tissue; and to differentiate between the tumour core and the surrounding oedema. This paper presents two contributions. First, we develop tumour seed selection based on multiscale multi-modal texture feature vectors. Second, we develop a method based on a local phase congruency based feature map to drive level-set segmentation. The segmentations achieved with our method are more accurate than previously presented methods, particularly for challenging low grade tumours.

  10. The 2007 WHO Classification of Tumours of the Central Nervous System

    PubMed Central

    Louis, David N.; Ohgaki, Hiroko; Wiestler, Otmar D.; Cavenee, Webster K.; Burger, Peter C.; Jouvet, Anne; Scheithauer, Bernd W.

    2007-01-01

    The fourth edition of the World Health Organization (WHO) classification of tumours of the central nervous system, published in 2007, lists several new entities, including angiocentric glioma, papillary glioneuronal tumour, rosette-forming glioneuronal tumour of the fourth ventricle, papillary tumour of the pineal region, pituicytoma and spindle cell oncocytoma of the adenohypophysis. Histological variants were added if there was evidence of a different age distribution, location, genetic profile or clinical behaviour; these included pilomyxoid astrocytoma, anaplastic medulloblastoma and medulloblastoma with extensive nodularity. The WHO grading scheme and the sections on genetic profiles were updated and the rhabdoid tumour predisposition syndrome was added to the list of familial tumour syndromes typically involving the nervous system. As in the previous, 2000 edition of the WHO ‘Blue Book’, the classification is accompanied by a concise commentary on clinico-pathological characteristics of each tumour type. The 2007 WHO classification is based on the consensus of an international Working Group of 25 pathologists and geneticists, as well as contributions from more than 70 international experts overall, and is presented as the standard for the definition of brain tumours to the clinical oncology and cancer research communities world-wide. PMID:17618441

  11. Neuropsychological Differences between Survivors of Supratentorial and Infratentorial Brain Tumours

    ERIC Educational Resources Information Center

    Patel, S. K.; Mullins, W. A.; O'Neil, S. H.; Wilson, K.

    2011-01-01

    Background: The purpose of this study is to evaluate the relationship between brain tumour location and core areas of cognitive and behavioural functioning for paediatric brain tumour survivors. The extant literature both supports and refutes an association between paediatric brain tumour location and neurocognitive outcomes. We examined…

  12. Neuropsychological Differences between Survivors of Supratentorial and Infratentorial Brain Tumours

    ERIC Educational Resources Information Center

    Patel, S. K.; Mullins, W. A.; O'Neil, S. H.; Wilson, K.

    2011-01-01

    Background: The purpose of this study is to evaluate the relationship between brain tumour location and core areas of cognitive and behavioural functioning for paediatric brain tumour survivors. The extant literature both supports and refutes an association between paediatric brain tumour location and neurocognitive outcomes. We examined…

  13. Imaging biomarkers in primary brain tumours.

    PubMed

    Lopci, Egesta; Franzese, Ciro; Grimaldi, Marco; Zucali, Paolo Andrea; Navarria, Pierina; Simonelli, Matteo; Bello, Lorenzo; Scorsetti, Marta; Chiti, Arturo

    2015-04-01

    We are getting used to referring to instrumentally detectable biological features in medical language as "imaging biomarkers". These two terms combined reflect the evolution of medical imaging during recent decades, and conceptually comprise the principle of noninvasive detection of internal processes that can become targets for supplementary therapeutic strategies. These targets in oncology include those biological pathways that are associated with several tumour features including independence from growth and growth-inhibitory signals, avoidance of apoptosis and immune system control, unlimited potential for replication, self-sufficiency in vascular supply and neoangiogenesis, acquired tissue invasiveness and metastatic diffusion. Concerning brain tumours, there have been major improvements in neurosurgical techniques and radiotherapy planning, and developments of novel target drugs, thus increasing the need for reproducible, noninvasive, quantitative imaging biomarkers. However, in this context, conventional radiological criteria may be inappropriate to determine the best therapeutic option and subsequently to assess response to therapy. Integration of molecular imaging for the evaluation of brain tumours has for this reason become necessary, and an important role in this setting is played by imaging biomarkers in PET and MRI. In the current review, we describe most relevant techniques and biomarkers used for imaging primary brain tumours in clinical practice, and discuss potential future developments from the experimental context. PMID:25520293

  14. Combined texture feature analysis of segmentation and classification of benign and malignant tumour CT slices.

    PubMed

    Padma, A; Sukanesh, R

    2013-01-01

    A computer software system is designed for the segmentation and classification of benign from malignant tumour slices in brain computed tomography (CT) images. This paper presents a method to find and select both the dominant run length and co-occurrence texture features of region of interest (ROI) of the tumour region of each slice to be segmented by Fuzzy c means clustering (FCM) and evaluate the performance of support vector machine (SVM)-based classifiers in classifying benign and malignant tumour slices. Two hundred and six tumour confirmed CT slices are considered in this study. A total of 17 texture features are extracted by a feature extraction procedure, and six features are selected using Principal Component Analysis (PCA). This study constructed the SVM-based classifier with the selected features and by comparing the segmentation results with the experienced radiologist labelled ground truth (target). Quantitative analysis between ground truth and segmented tumour is presented in terms of segmentation accuracy, segmentation error and overlap similarity measures such as the Jaccard index. The classification performance of the SVM-based classifier with the same selected features is also evaluated using a 10-fold cross-validation method. The proposed system provides some newly found texture features have an important contribution in classifying benign and malignant tumour slices efficiently and accurately with less computational time. The experimental results showed that the proposed system is able to achieve the highest segmentation and classification accuracy effectiveness as measured by jaccard index and sensitivity and specificity. PMID:23094909

  15. Brain tumour cells interconnect to a functional and resistant network.

    PubMed

    Osswald, Matthias; Jung, Erik; Sahm, Felix; Solecki, Gergely; Venkataramani, Varun; Blaes, Jonas; Weil, Sophie; Horstmann, Heinz; Wiestler, Benedikt; Syed, Mustafa; Huang, Lulu; Ratliff, Miriam; Karimian Jazi, Kianush; Kurz, Felix T; Schmenger, Torsten; Lemke, Dieter; Gömmel, Miriam; Pauli, Martin; Liao, Yunxiang; Häring, Peter; Pusch, Stefan; Herl, Verena; Steinhäuser, Christian; Krunic, Damir; Jarahian, Mostafa; Miletic, Hrvoje; Berghoff, Anna S; Griesbeck, Oliver; Kalamakis, Georgios; Garaschuk, Olga; Preusser, Matthias; Weiss, Samuel; Liu, Haikun; Heiland, Sabine; Platten, Michael; Huber, Peter E; Kuner, Thomas; von Deimling, Andreas; Wick, Wolfgang; Winkler, Frank

    2015-12-01

    Astrocytic brain tumours, including glioblastomas, are incurable neoplasms characterized by diffusely infiltrative growth. Here we show that many tumour cells in astrocytomas extend ultra-long membrane protrusions, and use these distinct tumour microtubes as routes for brain invasion, proliferation, and to interconnect over long distances. The resulting network allows multicellular communication through microtube-associated gap junctions. When damage to the network occurred, tumour microtubes were used for repair. Moreover, the microtube-connected astrocytoma cells, but not those remaining unconnected throughout tumour progression, were protected from cell death inflicted by radiotherapy. The neuronal growth-associated protein 43 was important for microtube formation and function, and drove microtube-dependent tumour cell invasion, proliferation, interconnection, and radioresistance. Oligodendroglial brain tumours were deficient in this mechanism. In summary, astrocytomas can develop functional multicellular network structures. Disconnection of astrocytoma cells by targeting their tumour microtubes emerges as a new principle to reduce the treatment resistance of this disease. PMID:26536111

  16. Automated EEG signal analysis for identification of epilepsy seizures and brain tumour.

    PubMed

    Sharanreddy, M; Kulkarni, P K

    2013-11-01

    Abstract Electroencephalography (EEG) is a clinical test which records neuro-electrical activities generated by brain structures. EEG test results used to monitor brain diseases such as epilepsy seizure, brain tumours, toxic encephalopathies infections and cerebrovascular disorders. Due to the extreme variation in the EEG morphologies, manual analysis of the EEG signal is laborious, time consuming and requires skilled interpreters, who by the nature of the task are prone to subjective judegment and error. Further, manual analysis of the EEG results often fails to detect and uncover subtle features. This paper proposes an automated EEG analysis method by combining digital signal processing and neural network techniques, which will remove error and subjectivity associated with manual analysis and identifies the existence of epilepsy seizure and brain tumour diseases. The system uses multi-wavelet transform for feature extraction in which an input EEG signal is decomposed in a sub-signal. Irregularities and unpredictable fluctuations present in the decomposed signal are measured using approximate entropy. A feed-forward neural network is used to classify the EEG signal as a normal, epilepsy or brain tumour signal. The proposed technique is implemented and tested on data of 500 EEG signals for each disease. Results are promising, with classification accuracy of 98% for normal, 93% for epilepsy and 87% for brain tumour. Along with classification, the paper also highlights the EEG abnormalities associated with brain tumour and epilepsy seizure. PMID:24116656

  17. Objectivity in the classification of tumours of the nasal epithelium

    PubMed Central

    Michaels, L.; Hyams, V. J.

    1975-01-01

    A survey of tumours derived from each of the four cell types of nasal epithelium is presented. Criticism is levelled at the adoption of additional terms for tissue types such as lympho-epithelium and transitional cell epithelium and tumours said to be derived from them. Electron microscopy is of assistance in classification particularly in the detection of evidence of keratin synthesis. The proposed classification of tumours of the nasal epithelium is: (1) Pseudostratified columnar epithelium: (a) papillary adenoma, (b) papillary carcinoma. (2) Squamous epithelium: (a) everted squamous papilloma, (b) inverted papilloma, (c) squamous carcinoma of any grade of differentiation from well differentiated to undifferentiated. (3) Melanocyte: malignant melanoma. (4) Olfactory neuroepithelium: olfactory neuroblastoma. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11Fig. 12Fig. 13Fig. 14Fig. 15Fig. 16Fig. 17Fig. 18Fig. 19Fig. 21Fig. 20 PMID:1197175

  18. Extraction of specific parameters for skin tumour classification

    PubMed Central

    Messadi, M.; Bessaid, A.; Taleb-Ahmed, A.

    2009-01-01

    In this paper, a methodological approach to the classification of tumour skin lesions in dermoscopy images is presented. Melanomas are the most malignant skin tumours. They grow in melanocytes, the cells responsible for pigmentation. This type of cancer is increasing rapidly; its related mortality rate is increasing more modestly, and inversely proportional to the thickness of the tumour. The mortality rate can be decreased by earlier detection of suspicious lesions and better prevention. Using skin tumour features such as colour, symmetry and border regularity, an attempt is made to determine if the skin tumour is a melanoma or a benign tumour. In this work, we are interested in extracting specific attributes which can be used for computer-aided diagnosis of melanoma, especially among general practitioners. In the first step, we eliminate surrounding hair in order to eliminate the residual noise. In the second step, an automatic segmentation is applied to the image of the skin tumour. This method reduces a colour image into an intensity image and approximately segments the image by intensity thresholding. Then, it refines the segmentation using the image edges, which are used to localize the boundary in that area of the skin. This step is essential to characterize the shape of the lesion and also to locate the tumour for analysis. Then, a sequences of transformations is applied to the image to measure a set of attributes (A: asymmetry, B: border, C: colour and D: diameter) which contain sufficient information to differentiate a melanoma from benign lesions. Finally, the various signs of specific lesion (ABCD) are provided to an artificial neural network to differentiate between malignant tumours and benign lesions. PMID:19384704

  19. Extraction of specific parameters for skin tumour classification.

    PubMed

    Messadi, M; Bessaid, A; Taleb-Ahmed, A

    2009-01-01

    In this paper, a methodological approach to the classification of tumour skin lesions in dermoscopy images is presented. Melanomas are the most malignant skin tumours. They grow in melanocytes, the cells responsible for pigmentation. This type of cancer is increasing rapidly; its related mortality rate is increasing more modestly, and inversely proportional to the thickness of the tumour. The mortality rate can be decreased by earlier detection of suspicious lesions and better prevention. Using skin tumour features such as colour, symmetry and border regularity, an attempt is made to determine if the skin tumour is a melanoma or a benign tumour. In this work, we are interested in extracting specific attributes which can be used for computer-aided diagnosis of melanoma, especially among general practitioners. In the first step, we eliminate surrounding hair in order to eliminate the residual noise. In the second step, an automatic segmentation is applied to the image of the skin tumour. This method reduces a colour image into an intensity image and approximately segments the image by intensity thresholding. Then, it refines the segmentation using the image edges, which are used to localize the boundary in that area of the skin. This step is essential to characterize the shape of the lesion and also to locate the tumour for analysis. Then, a sequences of transformations is applied to the image to measure a set of attributes (A: asymmetry, B: border, C: colour and D: diameter) which contain sufficient information to differentiate a melanoma from benign lesions. Finally, the various signs of specific lesion (ABCD) are provided to an artificial neural network to differentiate between malignant tumours and benign lesions. PMID:19384704

  20. Brain tumours in children: importance of early identification.

    PubMed

    Fry, Charles William; Perrow, Rachel; Paul, Siba Prosad

    A Brain tumours account for a quarter of all childhood cancers in the UK but are the leading cause of cancer-related deaths in children. Studies have previously shown that there is a delay in diagnosing brain tumours in children in the UK. The HeadSmart campaign was launched to increase awareness among health professionals working in different settings regarding brain tumour symptoms in children. Although headache is considered to be one of the most important symptoms, it is not often reported in paediatric practice, especially if the child is young. The HeadSmart symptom card is a useful resource and should be used when dealing with a child with symptoms suggestive of brain tumours. Nurses working in different settings play a vital role in early identification of brain tumours and also in supporting the child and his/her family through the child's journey following diagnosis of a brain tumour. The HeadSmart campaign has led to a reduction in the total diagnostic interval, to 7 weeks, and the ultimate aim is to reduce it further to 5 weeks which will be on a par with the time taken to diagnose brain tumours in children in other developed countries. PMID:25492435

  1. MicroRNA Regulation of Brain Tumour Initiating Cells in Central Nervous System Tumours

    PubMed Central

    Vijayakumar, Thusyanth; Bakhshinyan, David; Venugopal, Chitra; Singh, Sheila K.

    2015-01-01

    CNS tumours occur in both pediatric and adult patients and many of these tumours are associated with poor clinical outcome. Due to a paradigm shift in thinking for the last several years, these tumours are now considered to originate from a small population of stem-like cells within the bulk tumour tissue. These cells, termed as brain tumour initiating cells (BTICs), are perceived to be regulated by microRNAs at the posttranscriptional/translational levels. Proliferation, stemness, differentiation, invasion, angiogenesis, metastasis, apoptosis, and cell cycle constitute some of the significant processes modulated by microRNAs in cancer initiation and progression. Characterization and functional studies on oncogenic or tumour suppressive microRNAs are made possible because of developments in sequencing and microarray techniques. In the current review, we bring recent knowledge of the role of microRNAs in BTIC formation and therapy. Special attention is paid to two highly aggressive and well-characterized brain tumours: gliomas and medulloblastoma. As microRNA seems to be altered in the pathogenesis of many human diseases, “microRNA therapy” may now have potential to improve outcomes for brain tumour patients. In this rapidly evolving field, further understanding of miRNA biology and its contribution towards cancer can be mined for new therapeutic tools. PMID:26064134

  2. Spectral and lifetime domain measurements of rat brain tumours

    NASA Astrophysics Data System (ADS)

    Abi Haidar, D.; Leh, B.; Allaoua, K.; Genoux, A.; Siebert, R.; Steffenhagen, M.; Peyrot, D.; Sandeau, N.; Vever-Bizet, C.; Bourg-Heckly, G.; Chebbi, I.; Collado-Hilly, M.

    2012-02-01

    During glioblastoma surgery, delineation of the brain tumour margins remains difficult especially since infiltrated and normal tissues have the same visual appearance. This problematic constitutes our research interest. We developed a fibre-optical fluorescence probe for spectroscopic and time domain measurements. First measurements of endogenous tissue fluorescence were performed on fresh and fixed rat tumour brain slices. Spectral characteristics, fluorescence redox ratios and fluorescence lifetime measurements were analysed. Fluorescence information collected from both, lifetime and spectroscopic experiments, appeared promising for tumour tissue discrimination. Two photon measurements were performed on the same fixed tissue. Different wavelengths are used to acquire two-photon excitation-fluorescence of tumorous and healthy sites.

  3. Residential Radon and Brain Tumour Incidence in a Danish Cohort

    PubMed Central

    Bräuner, Elvira V.; Andersen, Zorana J.; Andersen, Claus E.; Pedersen, Camilla; Gravesen, Peter; Ulbak, Kaare; Hertel, Ole; Loft, Steffen; Raaschou-Nielsen, Ole

    2013-01-01

    Background Increased brain tumour incidence over recent decades may reflect improved diagnostic methods and clinical practice, but remain unexplained. Although estimated doses are low a relationship between radon and brain tumours may exist. Objective To investigate the long-term effect of exposure to residential radon on the risk of primary brain tumour in a prospective Danish cohort. Methods During 1993–1997 we recruited 57,053 persons. We followed each cohort member for cancer occurrence from enrolment until 31 December 2009, identifying 121 primary brain tumour cases. We traced residential addresses from 1 January 1971 until 31 December 2009 and calculated radon concentrations at each address using information from central databases regarding geology and house construction. Cox proportional hazards models were used to estimate incidence rate-ratios (IRR) and 95% confidence intervals (CI) for the risk of primary brain tumours associated with residential radon exposure with adjustment for age, sex, occupation, fruit and vegetable consumption and traffic-related air pollution. Effect modification by air pollution was assessed. Results Median estimated radon was 40.5 Bq/m3. The adjusted IRR for primary brain tumour associated with each 100 Bq/m3 increment in average residential radon levels was 1.96 (95% CI: 1.07; 3.58) and this was exposure-dependently higher over the four radon exposure quartiles. This association was not modified by air pollution. Conclusions We found significant associations and exposure-response patterns between long-term residential radon exposure radon in a general population and risk of primary brain tumours, adding new knowledge to this field. This finding could be chance and needs to be challenged in future studies. PMID:24066143

  4. [Chronic secondary hypoparathyroidism and pseudo-brain tumour (author's transl)].

    PubMed

    Sollberg, G

    1975-10-24

    A 31-year-old man developed chronic secondary hypoparathyroidism after removal of goitre. Asymmetric cerebral oedema occured and a classical picture of pseudo-brain tumour with severe cerebral involvement developed which regressed merely on administration of calcium ions. The patient has remained well for over a year on dihydrotachysterol maintenance. PMID:1175470

  5. Current approaches to the treatment of metastatic brain tumours

    PubMed Central

    Owonikoko, Taofeek K.; Arbiser, Jack; Zelnak, Amelia; Shu, Hui-Kuo G.; Shim, Hyunsuk; Robin, Adam M.; Kalkanis, Steven N.; Whitsett, Timothy G.; Salhia, Bodour; Tran, Nhan L.; Ryken, Timothy; Moore, Michael K.; Egan, Kathleen M.; Olson, Jeffrey J.

    2014-01-01

    Metastatic tumours involving the brain overshadow primary brain neoplasms in frequency and are an important complication in the overall management of many cancers. Importantly, advances are being made in understanding the molecular biology underlying the initial development and eventual proliferation of brain metastases. Surgery and radiation remain the cornerstones of the therapy for symptomatic lesions; however, image-based guidance is improving surgical technique to maximize the preservation of normal tissue, while more sophisticated approaches to radiation therapy are being used to minimize the long-standing concerns over the toxicity of whole-brain radiation protocols used in the past. Furthermore, the burgeoning knowledge of tumour biology has facilitated the entry of systemically administered therapies into the clinic. Responses to these targeted interventions have ranged from substantial toxicity with no control of disease to periods of useful tumour control with no decrement in performance status of the treated individual. This experience enables recognition of the limits of targeted therapy, but has also informed methods to optimize this approach. This Review focuses on the clinically relevant molecular biology of brain metastases, and summarizes the current applications of these data to imaging, surgery, radiation therapy, cytotoxic chemotherapy and targeted therapy. PMID:24569448

  6. Cerebrospinal fluid-derived circulating tumour DNA better represents the genomic alterations of brain tumours than plasma.

    PubMed

    De Mattos-Arruda, Leticia; Mayor, Regina; Ng, Charlotte K Y; Weigelt, Britta; Martínez-Ricarte, Francisco; Torrejon, Davis; Oliveira, Mafalda; Arias, Alexandra; Raventos, Carolina; Tang, Jiabin; Guerini-Rocco, Elena; Martínez-Sáez, Elena; Lois, Sergio; Marín, Oscar; de la Cruz, Xavier; Piscuoglio, Salvatore; Towers, Russel; Vivancos, Ana; Peg, Vicente; Ramon y Cajal, Santiago; Carles, Joan; Rodon, Jordi; González-Cao, María; Tabernero, Josep; Felip, Enriqueta; Sahuquillo, Joan; Berger, Michael F; Cortes, Javier; Reis-Filho, Jorge S; Seoane, Joan

    2015-01-01

    Cell-free circulating tumour DNA (ctDNA) in plasma has been shown to be informative of the genomic alterations present in tumours and has been used to monitor tumour progression and response to treatments. However, patients with brain tumours do not present with or present with low amounts of ctDNA in plasma precluding the genomic characterization of brain cancer through plasma ctDNA. Here we show that ctDNA derived from central nervous system tumours is more abundantly present in the cerebrospinal fluid (CSF) than in plasma. Massively parallel sequencing of CSF ctDNA more comprehensively characterizes the genomic alterations of brain tumours than plasma, allowing the identification of actionable brain tumour somatic mutations. We show that CSF ctDNA levels longitudinally fluctuate in time and follow the changes in brain tumour burden providing biomarkers to monitor brain malignancies. Moreover, CSF ctDNA is shown to facilitate and complement the diagnosis of leptomeningeal carcinomatosis. PMID:26554728

  7. Clinical update: recognising brain tumours early in children.

    PubMed

    Paul, Siba Prosad; Debono, Rachel; Walker, David

    2013-04-01

    Brain tumour accounts for a quarter of all childhood cancers and is the leading cause of cancer related deaths in children. Initial symptoms can be misleading and is often misinterpreted as being caused by a less serious childhood illness. Available statistics show that it takes almost three times longer for the brain tumour in children to get diagnosed in the United Kingdom in comparison to other developed countries. Head Smart campaign was launched in the UK in 2011 with an aim to decrease the time from the onset of symptoms to diagnosis; initial results have been highly encouraging. Community practitioners play an important role in not only identifying symptoms (by following Head Smart symptom card) and selecting patients for reassurance, review or early referral but also by providing valuable support to the family post diagnosis in the community. PMID:23646820

  8. NANOTECHNOLOGY - NEW TRENDS IN THE TREATMENT OF BRAIN TUMOURS.

    PubMed

    Kr?pa, Petr; ?ehák, Svatopluk; Diaz-Garcia, Daniel; Filip, Stanislav

    2014-01-01

    High grade gliomas are some of the deadliest human tumours. Conventional treatments such as surgery, radiotherapy and chemotherapy have only a limited effect. Nowadays, resection is the common treatment of choice and although new approaches, such as perioperative magnetic resonance imaging or fluorescent microscopy have been developed, the survival rate of diagnosed patients is still very low. The inefficacy of conventional methods has led to the development of new strategies and the significant progress of nanotechnology in recent years. These platforms can be used either as novel imaging tools or to improve anticancer drug delivery into tumours while minimizing its distribution and toxicity in healthy tissues. Amongst the new nanotechnology platforms used for delivery into the brain tissue are: polymeric nanoparticles, liposomes, dendrimers, nanoshells, carbon nanotubes, superparamagnetic nanoparticles and nucleic acid based nanoparticles (DNA, RNA interference [RNAi] and antisense oligonucleotides [ASO]). These nanoparticles have been applied in the delivery of small molecular weight drugs as well as macromolecules - proteins, peptides and genes. The unique properties of these nanoparticles, such as surface charge, particle size, composition and ability to modify their surface with tissue recognition ligands and antibodies, improve their biodistribution and pharmacokinetics. All of the above mentioned characteristics make of nanoplatforms a very suitable tool for its use in targeted, personalized medicine, where they could possibly carry large doses of therapeutic agents specifically into malignant cells while avoiding healthy cells. This review poses new possibilities in the large field of nanotechnology with special interest in the treatment of high grade brain tumours. PMID:25938897

  9. Somatic CRISPR/Cas9-mediated tumour suppressor disruption enables versatile brain tumour modelling

    PubMed Central

    Zuckermann, Marc; Hovestadt, Volker; Knobbe-Thomsen, Christiane B.; Zapatka, Marc; Northcott, Paul A.; Schramm, Kathrin; Belic, Jelena; Jones, David T. W.; Tschida, Barbara; Moriarity, Branden; Largaespada, David; Roussel, Martine F.; Korshunov, Andrey; Reifenberger, Guido; Pfister, Stefan M.; Lichter, Peter; Kawauchi, Daisuke; Gronych, Jan

    2015-01-01

    In vivo functional investigation of oncogenes using somatic gene transfer has been successfully exploited to validate their role in tumorigenesis. For tumour suppressor genes this has proven more challenging due to technical aspects. To provide a flexible and effective method for investigating somatic loss-of-function alterations and their influence on tumorigenesis, we have established CRISPR/Cas9-mediated somatic gene disruption, allowing for in vivo targeting of TSGs. Here we demonstrate the utility of this approach by deleting single (Ptch1) or multiple genes (Trp53, Pten, Nf1) in the mouse brain, resulting in the development of medulloblastoma and glioblastoma, respectively. Using whole-genome sequencing (WGS) we characterized the medulloblastoma-driving Ptch1 deletions in detail and show that no off-targets were detected in these tumours. This method provides a fast and convenient system for validating the emerging wealth of novel candidate tumour suppressor genes and the generation of faithful animal models of human cancer. PMID:26067104

  10. Somatic CRISPR/Cas9-mediated tumour suppressor disruption enables versatile brain tumour modelling.

    PubMed

    Zuckermann, Marc; Hovestadt, Volker; Knobbe-Thomsen, Christiane B; Zapatka, Marc; Northcott, Paul A; Schramm, Kathrin; Belic, Jelena; Jones, David T W; Tschida, Barbara; Moriarity, Branden; Largaespada, David; Roussel, Martine F; Korshunov, Andrey; Reifenberger, Guido; Pfister, Stefan M; Lichter, Peter; Kawauchi, Daisuke; Gronych, Jan

    2015-01-01

    In vivo functional investigation of oncogenes using somatic gene transfer has been successfully exploited to validate their role in tumorigenesis. For tumour suppressor genes this has proven more challenging due to technical aspects. To provide a flexible and effective method for investigating somatic loss-of-function alterations and their influence on tumorigenesis, we have established CRISPR/Cas9-mediated somatic gene disruption, allowing for in vivo targeting of TSGs. Here we demonstrate the utility of this approach by deleting single (Ptch1) or multiple genes (Trp53, Pten, Nf1) in the mouse brain, resulting in the development of medulloblastoma and glioblastoma, respectively. Using whole-genome sequencing (WGS) we characterized the medulloblastoma-driving Ptch1 deletions in detail and show that no off-targets were detected in these tumours. This method provides a fast and convenient system for validating the emerging wealth of novel candidate tumour suppressor genes and the generation of faithful animal models of human cancer. PMID:26067104

  11. Review of metastatic spine tumour classification and indications for surgery: the consensus statement of the Global Spine Tumour Study Group

    PubMed Central

    Crockard, A.; Bunger, C.; Harms, J.; Kawahara, N.; Mazel, C.; Melcher, R.; Tomita, K.

    2009-01-01

    Choosing the right operation for metastatic spinal tumours is often difficult, and depends on many factors, including life expectancy and the balance of the risk of surgery against the likelihood of improving quality of life. Several prognostic scores have been devised to help the clinician decide the most appropriate course of action, but there still remains controversy over how to choose the best option; more often the decision is influenced by habit, belief and subjective experience. The purpose of this article is to review the present systems available for classifying spinal metastases, how these classifications can be used to help surgical planning, discuss surgical outcomes, and make suggestions for future research. It is important for spinal surgeons to reach a consensus regarding the classification of spinal metastases and surgical strategies. The authors of this article constitute the Global Spine Tumour Study Group: an international group of spinal surgeons who are dedicated to studying the techniques and outcomes of surgery for spinal tumours, to build on the existing evidence base for the surgical treatment of spinal tumours. PMID:20039084

  12. Endometrial stromal tumours revisited: an update based on the 2014 WHO classification.

    PubMed

    Ali, Rola H; Rouzbahman, Marjan

    2015-05-01

    Endometrial stromal tumours (EST) are rare tumours of endometrial stromal origin that account for less than 2% of all uterine tumours. Recent cytogenetic and molecular advances in this area have improved our understanding of ESTs and helped refine their classification into more meaningful categories. Accordingly, the newly released 2014 WHO classification system recognises four categories: endometrial stromal nodule (ESN), low-grade endometrial stromal sarcoma (LGESS), high-grade endometrial stromal sarcoma (HGESS) and undifferentiated uterine sarcoma (UUS). At the molecular level, these tumours may demonstrate a relatively simple karyotype with a defining chromosomal rearrangement (as in the majority of ESNs, LGESSs and YWHAE-rearranged HGESS) or demonstrate complex cytogenetic aberrations lacking specific rearrangements (as in UUSs). Herein we provide an update on this topic aimed at the practicing pathologist. PMID:25595274

  13. Interventions for cognitive deficits in adults with brain tumours.

    PubMed

    Gehring, Karin; Sitskoorn, Margriet M; Aaronson, Neil K; Taphoorn, Martin J B

    2008-06-01

    Increased life expectancy in patients with brain tumours has led to a greater risk of cognitive deficits, particularly during disease-free periods. Here, we review the empirical studies that have been done to treat or to prevent cognitive impairment in patients with brain tumours. Both pharmacological interventions and cognitive rehabilitation programmes have been used. Although both types of study have reported some successes, these are often difficult to interpret owing to limitations in the methods used. Most of the studies reviewed did not use a randomised group design to control for possible confounding factors such as placebo and practice effects. Investigations of newer, targeted therapies have reported delays in cognitive deterioration, but these need to be confirmed in future studies. Neuroprotection represents another potentially promising, novel approach to prevention of cognitive impairment in this vulnerable population of patients. Finally, we describe studies in patients with cancers outside the CNS, to highlight further possibilities for the prevention and treatment of cognitive deficits. PMID:18485318

  14. Tissue Tracking: Applications for Brain MRI Classification

    PubMed Central

    Melonakos, John; Gao, Yi; Tannenbaum, Allen

    2013-01-01

    Bayesian classification methods have been extensively used in a variety of image processing applications, including medical image analysis. The basic procedure is to combine data-driven knowledge in the likelihood terms with clinical knowledge in the prior terms to classify an image into a pre-determined number of classes. In many applications, it is difficult to construct meaningful priors and, hence, homogeneous priors are assumed. In this paper, we show how expectation-maximization weights and neighboring posterior probabilities may be combined to make intuitive use of the Bayesian priors. Drawing upon insights from computer vision tracking algorithms, we cast the problem in a tissue tracking framework. We show results of our algorithm on the classification of gray and white matter along with surrounding cerebral spinal fluid in brain MRI scans. We show results of our algorithm on 20 brain MRI datasets along with validation against expert manual segmentations. PMID:24392193

  15. Ethics roundtable debate: child with severe brain damage and an underlying brain tumour.

    PubMed

    Gunn, Scott; Hashimoto, Satoru; Karakozov, Michael; Marx, Thomas; Tan, Ian K S; Thompson, Dan R; Vincent, Jean-Louis

    2004-08-01

    A young person presents with a highly malignant brain tumour with hemiparesis and limited prognosis after resection. She then suffers an iatrogenic cardiac and respiratory arrest that results in profound anoxic encephalopathy. A difference in opinion between the treatment team and the parent is based on a question of futile therapy. Opinions from five intensivists from around the world explore the differences in ethical and legal issues. A Physician-ethicist comments on the various approaches. PMID:15312199

  16. Guiding intracortical brain tumour cells to an extracortical cytotoxic hydrogel using aligned polymeric nanofibres

    NASA Astrophysics Data System (ADS)

    Jain, Anjana; Betancur, Martha; Patel, Gaurangkumar D.; Valmikinathan, Chandra M.; Mukhatyar, Vivek J.; Vakharia, Ajit; Pai, S. Balakrishna; Brahma, Barunashish; MacDonald, Tobey J.; Bellamkonda, Ravi V.

    2014-03-01

    Glioblastoma multiforme is an aggressive, invasive brain tumour with a poor survival rate. Available treatments are ineffective and some tumours remain inoperable because of their size or location. The tumours are known to invade and migrate along white matter tracts and blood vessels. Here, we exploit this characteristic of glioblastoma multiforme by engineering aligned polycaprolactone (PCL)-based nanofibres for tumour cells to invade and, hence, guide cells away from the primary tumour site to an extracortical location. This extracortial sink is a cyclopamine drug-conjugated, collagen-based hydrogel. When aligned PCL-nanofibre films in a PCL/polyurethane carrier conduit were inserted in the vicinity of an intracortical human U87MG glioblastoma xenograft, a significant number of human glioblastoma cells migrated along the aligned nanofibre films and underwent apoptosis in the extracortical hydrogel. Tumour volume in the brain was significantly lower following insertion of aligned nanofibre implants compared with the application of smooth fibres or no implants.

  17. Combined radiotherapy and chemotherapy for high-grade brain tumours

    NASA Astrophysics Data System (ADS)

    Barazzuol, Lara

    Glioblastoma (GBM) is the most common primary brain tumour in adults and among the most aggressive of all tumours. For several decades, the standard care of GBM was surgical resection followed by radiotherapy alone. In 2005, a landmark phase III clinical trial coordinated by the European Organization for Research and Treatment of Cancer (EORTC) and the National Cancer Institute of Canada (NCIC) demonstrated the benefit of radiotherapy with concomitant and adjuvant temozolomide (TMZ) chemotherapy. With TMZ, the median life expectancy in optimally managed patients is still only 12-14 months, with only 25% surviving 24 months. There is an urgent need for new therapies in particular in those patients whose tumour has an unmethylated methylguanine methyltransferase gene (MGMT) promoter, which is a predictive factor of benefit from TMZ. In this dissertation, the nature of the interaction between TMZ and radiation is investigated using both a mathematical model, based on in vivo population statistics of survival, and in vitro experimentation on a panel of human GBM cell lines. The results show that TMZ has an additive effect in vitro and that the population-based model may be insufficient in predicting TMZ response. The combination of TMZ with particle therapy is also investigated. Very little preclinical data exists on the effects of charged particles on GBM cell lines as well as on the concomitant application of chemotherapy. In this study, human GBM cells are exposed to 3 MeV protons and 6 MeV alpha particles in concomitance with TMZ. The results suggest that the radiation quality does not affect the nature of the interaction between TMZ and radiation, showing reproducible additive cytotoxicity. Since TMZ and radiation cause DNA damage in cancer cells, there has been increased attention to the use of poly(ADP-ribose) polymerase (PARP) inhibitors. PARP is a family of enzymes that play a key role in the repair of DNA breaks. In this study, a novel PARP inhibitor, ABT-888, is used in combination with both TMZ and radiation. The results show that ABT-888 significantly enhances TMZ and radiation cell killing, regardless of the MGMT status. In summary, the findings of this research demonstrate that the use of particle therapy and PARP inhibitors are particularly promising and might improve the treatment outcome in patients with GBM.

  18. MRS water resonance frequency in childhood brain tumours: a novel potential biomarker of temperature and tumour environment.

    PubMed

    Babourina-Brooks, Ben; Wilson, Martin; Arvanitis, Theodoros N; Peet, Andrew C; Davies, Nigel P

    2014-10-01

    (1)H MRS thermometry has been investigated for brain trauma and hypothermia monitoring applications but has not been explored in brain tumours. The proton resonance frequency (PRF) of water is dependent on temperature but is also influenced by microenvironment factors, such as fast proton exchange with macromolecules, ionic concentration and magnetic susceptibility. (1)H MRS has been utilized for brain tumour diagnostic and prognostic purposes in children; however, the water PRF measure may provide complementary information to further improve characterization. Water PRF values were investigated from a repository of MRS data acquired from childhood brain tumours and children with apparently normal brains. The cohort consisted of histologically proven glioma (22), medulloblastoma (19) and control groups (28, MRS in both the basal ganglia and parietal white matter regions). All data were acquired at 1.5?T using a short TE (30?ms) single voxel spectroscopy (PRESS) protocol. Water PRF values were calculated using methyl creatine and total choline. Spectral peak amplitude weighted averaging was used to improve the accuracy of the measurements. Mean PRF values were significantly larger for medulloblastoma compared with glioma, with a difference in the means of 0.0147?ppm (p?brain. However, the PRF shift may not reflect a change in temperature, given that alterations in protein content, microstructure and ionic concentration contribute to PRF shifts. Measurement of these effects could also be used as a supplementary biomarker, and further investigation is required. This study has shown that the water PRF value has the potential to be used for characterizing childhood brain tumours, which has not been reported previously. PMID:25125325

  19. Transition Detection for Brain Computer Interface Classification

    NASA Astrophysics Data System (ADS)

    Aler, Ricardo; Galván, Inés M.; Valls, José M.

    This paper deals with the classification of signals for brain-computer interfaces (BCI). We take advantage of the fact that thoughts last for a period, and therefore EEG samples run in sequences belonging to the same class (thought). Thus, the classification problem can be reformulated into two subproblems: detecting class transitions and determining the class for sequences of samples between transitions. The method detects transitions when the L1 norm between the power spectra at two different times is larger than a threshold. To tackle the second problem, samples are classified by taking into account a window of previous predictions. Two types of windows have been tested: a constant-size moving window and a variable-size growing window. In both cases, results are competitive with those obtained in the BCI III competition.

  20. Non-negative matrix factorisation methods for the spectral decomposition of MRS data from human brain tumours

    PubMed Central

    2012-01-01

    Background In-vivo single voxel proton magnetic resonance spectroscopy (SV 1H-MRS), coupled with supervised pattern recognition (PR) methods, has been widely used in clinical studies of discrimination of brain tumour types and follow-up of patients bearing abnormal brain masses. SV 1H-MRS provides useful biochemical information about the metabolic state of tumours and can be performed at short (< 45 ms) or long (> 45 ms) echo time (TE), each with particular advantages. Short-TE spectra are more adequate for detecting lipids, while the long-TE provides a much flatter signal baseline in between peaks but also negative signals for metabolites such as lactate. Both, lipids and lactate, are respectively indicative of specific metabolic processes taking place. Ideally, the information provided by both TE should be of use for clinical purposes. In this study, we characterise the performance of a range of Non-negative Matrix Factorisation (NMF) methods in two respects: first, to derive sources correlated with the mean spectra of known tissue types (tumours and normal tissue); second, taking the best performing NMF method for source separation, we compare its accuracy for class assignment when using the mixing matrix directly as a basis for classification, as against using the method for dimensionality reduction (DR). For this, we used SV 1H-MRS data with positive and negative peaks, from a widely tested SV 1H-MRS human brain tumour database. Results The results reported in this paper reveal the advantage of using a recently described variant of NMF, namely Convex-NMF, as an unsupervised method of source extraction from SV1H-MRS. Most of the sources extracted in our experiments closely correspond to the mean spectra of some of the analysed tumour types. This similarity allows accurate diagnostic predictions to be made both in fully unsupervised mode and using Convex-NMF as a DR step previous to standard supervised classification. The obtained results are comparable to, or more accurate than those obtained with supervised techniques. Conclusions The unsupervised properties of Convex-NMF place this approach one step ahead of classical label-requiring supervised methods for the discrimination of brain tumour types, as it accounts for their increasingly recognised molecular subtype heterogeneity. The application of Convex-NMF in computer assisted decision support systems is expected to facilitate further improvements in the uptake of MRS-derived information by clinicians. PMID:22401579

  1. Targeting breast to brain metastatic tumours with death receptor ligand expressing therapeutic stem cells.

    PubMed

    Bagci-Onder, Tugba; Du, Wanlu; Figueiredo, Jose-Luiz; Martinez-Quintanilla, Jordi; Shah, Khalid

    2015-06-01

    Characterizing clinically relevant brain metastasis models and assessing the therapeutic efficacy in such models are fundamental for the development of novel therapies for metastatic brain cancers. In this study, we have developed an in vivo imageable breast-to-brain metastasis mouse model. Using real time in vivo imaging and subsequent composite fluorescence imaging, we show a widespread distribution of micro- and macro-metastasis in different stages of metastatic progression. We also show extravasation of tumour cells and the close association of tumour cells with blood vessels in the brain thus mimicking the multi-foci metastases observed in the clinics. Next, we explored the ability of engineered adult stem cells to track metastatic deposits in this model and show that engineered stem cells either implanted or injected via circulation efficiently home to metastatic tumour deposits in the brain. Based on the recent findings that metastatic tumour cells adopt unique mechanisms of evading apoptosis to successfully colonize in the brain, we reasoned that TNF receptor superfamily member 10A/10B apoptosis-inducing ligand (TRAIL) based pro-apoptotic therapies that induce death receptor signalling within the metastatic tumour cells might be a favourable therapeutic approach. We engineered stem cells to express a tumour selective, potent and secretable variant of a TRAIL, S-TRAIL, and show that these cells significantly suppressed metastatic tumour growth and prolonged the survival of mice bearing metastatic breast tumours. Furthermore, the incorporation of pro-drug converting enzyme, herpes simplex virus thymidine kinase, into therapeutic S-TRAIL secreting stem cells allowed their eradication post-tumour treatment. These studies are the first of their kind that provide insight into targeting brain metastasis with stem-cell mediated delivery of pro-apoptotic ligands and have important clinical implications. PMID:25910782

  2. Childhood brain tumours: associations with parental occupational exposure to solvents

    PubMed Central

    Peters, S; Glass, D C; Greenop, K R; Armstrong, B K; Kirby, M; Milne, E; Fritschi, L

    2014-01-01

    Background: Parental occupational exposures have been associated with childhood brain tumours (CBT), but results are inconsistent. Few studies have studied CBT risk and parental solvent exposure, suggesting a possible association. We examined the association between CBT and parental occupational exposure to solvents in a case–control study. Methods: Parents of 306 cases and 950 controls completed detailed occupational histories. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for both maternal and paternal exposure to benzene, other aromatics, aliphatics and chlorinated solvents in key time periods relative to the birth of their child. Adjustments were made for matching variables (child's age, sex and state of residence), best parental education and occupational exposure to diesel exhaust. Results: An increased risk of CBT was observed with maternal occupational exposures to chlorinated solvents (OR=8.59, 95% CI 0.94–78.9) any time before birth. Paternal exposure to solvents in the year before conception was associated with an increased CBT risk: OR=1.55 (95% CI 0.99–2.43). This increased risk appeared to be mainly attributable to exposure to aromatic solvents: OR=2.72 (95% CI 0.94–7.86) for benzene and OR=1.76 (95% CI 1.10–2.82) for other aromatics. Conclusions: Our results indicate that parental occupational exposures to solvents may be related to an increased risk of CBT. PMID:24960405

  3. Three-dimensional vasculature reconstruction of tumour microenvironment via local clustering and classification

    PubMed Central

    Zhu, Yanqiao; Li, Fuhai; Vadakkan, Tegy J.; Zhang, Mei; Landua, John; Wei, Wei; Ma, Jinwen; Dickinson, Mary E.; Rosen, Jeffrey M.; Lewis, Michael T.; Zhan, Ming; Wong, Stephen T. C.

    2013-01-01

    The vasculature inside breast cancers is one important component of the tumour microenvironment. The investigation of its spatial morphology, distribution and interactions with cancer cells, including cancer stem cells, is essential for elucidating mechanisms of tumour development and treatment response. Using confocal microscopy and fluorescent markers, we have acquired three-dimensional images of vasculature within mammary tumours and normal mammary gland of mouse models. However, it is difficult to segment and reconstruct complex vasculature accurately from the in vivo three-dimensional images owing to the existence of uneven intensity and regions with low signal-to-noise ratios (SNR). To overcome these challenges, we have developed a novel three-dimensional vasculature segmentation method based on local clustering and classification. First, images of vasculature are clustered into local regions, whose boundaries well delineate vasculature even in low SNR and uneven intensity regions. Then local regions belonging to vasculature are identified by applying a semi-supervised classification method based on three informative features of the local regions. Comparison of results using simulated and real vasculature images, from mouse mammary tumours and normal mammary gland, shows that the new method outperforms existing methods, and can be used for three-dimensional images with uneven background and low SNR to achieve accurate vasculature reconstruction. PMID:24511379

  4. Granular cell tumour of the brain and its cellular identity.

    PubMed

    Sakurama, N; Matsukado, Y; Marubayashi, T; Kodama, T

    1981-01-01

    Two cases of cerebral granular cell tumour are reported. In Case 1 the tumour arose from the genu of the corpus callosum, and in Case 2 it was found in the frontotemporoparietal lobes. Biopsy and autopsy specimens were examined with light and electron microscopy, and histochemical characteristics of the granule were analysed. Tumour cells from these two cases showed pleomorphism, but abundant granules in the cytoplasm were the most characteristic feature in these tumours. The granules were not stained by Sudan III and Sudan black, but were eosinophilic. They were PAS positive and not digested by diastase. Okamoto's reaction for glycolipid was positive after treatment by pyridine. They were also positive in Hotchkiss' method for glycolipid modified by Morrison and Hack, following immersion in chloroform and methanol solution. Histochemically, it was thought that granules consisted of glycoprotein. In the electron microscopic study dense bodies, multivesicular bodies, and vacoules were seen in tumour cells, especially in the neoplastic granular cells. It was assumed that the tumour cells originated from astrocytes, because of the cytoplasmic processes of the tumour cells were stained blue with PTAH, and contained microfibres of 80 A width. Gemistocytic astrocytes seen in the periphery of the tumour were also evidence indicating the neoplastic cell origin. PMID:6166157

  5. Mutation analysis of the p73 gene in nonastrocytic brain tumours

    PubMed Central

    Alonso, M E; Bello, M J; Gonzalez-Gomez, P; Lomas, J; Arjona, D; Campos, J M de; Kusak, M E; Sarasa, J L; Isla, A; Rey, J A

    2001-01-01

    Loss of heterozygosity (LOH) involving the distal chromosome 1p36region occurs frequently in nonastrocytic brain tumours, but the tumour suppressor gene targeted by this deletion is unknown. p73is a novel gene that has high sequence homology and similar gene structure to thep53 gene; it has been mapped to 1p36, and may thus represent a candidate for this tumour suppressor gene. To determine whether p73is involved in nonastrocytic brain tumour development, we analysed 65 tumour samples including 26 oligodendrogliomas, 4 ependymomas, 5 medulloblastomas, 10 meningiomas, 2 meningeal haemangiopericytomas, 2 neurofibrosarcomas, 3 primary lymphomas, 8 schwannomas and 5 metastatic tumours to the brain, for p73 alterations. Characterization of allelic loss at 1p36–p35 showed LOH in about 50% of cases, primarily involving oligodendroglial tumours (22 of 26 cases analysed; 85%) and meningiomas (4 of 10; 40%). PCR-SSCP and direct DNA sequencing of exons 2 to 14 of p73 revealed a missense mutation in one primary lymphoma: a G-to-A transition, with Glu291Lys change. 8 additional cases displayed no tumour-specific alterations, as 3 distinct polymorphic changes were identified: a double polymorphic change of exon 5 was found in one ependymoma and both samples derived from an oligodendroglioma, as follows: a G-to-A transition with no change in Pro 146, and a C-to-T variation with no change in Asn 204: a delG at exon 3/+12 position was identified in 4 samples corresponding to 2 oligodendrogliomas, 1 ependymoma and 1 meningioma, and a C-to-T change at exon 2/+10 position was present in a metastatic tumour. Although both LOH at 1p36 and p73 sequence changes were evidenced in 4 cases, it is difficult to establish a causal role of the p73 variations and nonastrocytic brain tumours development. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11461077

  6. Hierarchical probabilistic Gabor and MRF segmentation of brain tumours in MRI volumes.

    PubMed

    Subbanna, Nagesh K; Precup, Doina; Collins, D Louis; Arbel, Tal

    2013-01-01

    In this paper, we present a fully automated hierarchical probabilistic framework for segmenting brain tumours from multispectral human brain magnetic resonance images (MRIs) using multiwindow Gabor filters and an adapted Markov Random Field (MRF) framework. In the first stage, a customised Gabor decomposition is developed, based on the combined-space characteristics of the two classes (tumour and non-tumour) in multispectral brain MRIs in order to optimally separate tumour (including edema) from healthy brain tissues. A Bayesian framework then provides a coarse probabilistic texture-based segmentation of tumours (including edema) whose boundaries are then refined at the voxel level through a modified MRF framework that carefully separates the edema from the main tumour. This customised MRF is not only built on the voxel intensities and class labels as in traditional MRFs, but also models the intensity differences between neighbouring voxels in the likelihood model, along with employing a prior based on local tissue class transition probabilities. The second inference stage is shown to resolve local inhomogeneities and impose a smoothing constraint, while also maintaining the appropriate boundaries as supported by the local intensity difference observations. The method was trained and tested on the publicly available MICCAI 2012 Brain Tumour Segmentation Challenge (BRATS) Database [1] on both synthetic and clinical volumes (low grade and high grade tumours). Our method performs well compared to state-of-the-art techniques, outperforming the results of the top methods in cases of clinical high grade and low grade tumour core segmentation by 40% and 45% respectively. PMID:24505735

  7. Local Kernel for Brains Classification in Schizophrenia

    NASA Astrophysics Data System (ADS)

    Castellani, U.; Rossato, E.; Murino, V.; Bellani, M.; Rambaldelli, G.; Tansella, M.; Brambilla, P.

    In this paper a novel framework for brain classification is proposed in the context of mental health research. A learning by example method is introduced by combining local measurements with non linear Support Vector Machine. Instead of considering a voxel-by-voxel comparison between patients and controls, we focus on landmark points which are characterized by local region descriptors, namely Scale Invariance Feature Transform (SIFT). Then, matching is obtained by introducing the local kernel for which the samples are represented by unordered set of features. Moreover, a new weighting approach is proposed to take into account the discriminative relevance of the detected groups of features. Experiments have been performed including a set of 54 patients with schizophrenia and 54 normal controls on which region of interest (ROI) have been manually traced by experts. Preliminary results on Dorso-lateral PreFrontal Cortex (DLPFC) region are promising since up to 75% of successful classification rate has been obtained with this technique and the performance has improved up to 85% when the subjects have been stratified by sex.

  8. Association between nonsteroidal anti-inflammatory drug use and brain tumour risk: a meta-analysis

    PubMed Central

    Liu, Yanqiong; Lu, Yu; Wang, Jian; Xie, Li; Li, Taijie; He, Yu; Peng, Qiliu; Qin, Xue; Li, Shan

    2014-01-01

    Aims Several epidemiological studies have evaluated the association between nonsteroidal anti-inflammatory drugs (NSAIDs) and brain tumour risk. However, results from these studies have been inconsistent. The aim of this detailed meta-analysis is to review and summarize the evidence on this association. Methods A comprehensive search for articles published up to September 2013 was performed. Studies evaluating the association between exposure to NSAIDs and risk of brain tumours were included. Random-effects meta-analytical models were used to calculate the relative risk (RR) and corresponding 95% confidence intervals (CIs). Sensitivity analyses, Galbraith plots and subgroup analyses were also performed. Results Ten studies (six case–control studies, three cohort studies and one randomized controlled trial), published between 2003 and 2013, were included in this analysis. Compared with non-use, overall use of NSAIDs was not statistically significantly associated with brain tumour risk based on the random-effects models (RR = 1.01; 95% CI = 0.89, 1.15). No differences were observed when analyses were stratified by gender and brain tumour subtype. Specific analysis for aspirin and non-aspirin NSAIDs yielded similar results. However, a slightly increased risk of brain tumour in NSAID users was observed in cohort studies (RR = 1.32; 95% CI = 1.06, 1.64; P = 0.014). Furthermore, our analysis did not show a significant association between frequency and dose of aspirin use and brain tumour risk. Conclusions Use of NSAIDs (aspirin and non-aspirin NSAIDs) does not appear to be associated with brain tumour risk, but larger studies are needed to substantiate this relationship. PMID:24341448

  9. Human Cytomegalovirus Tegument Protein pp65 Is Detected in All Intra- and Extra-Axial Brain Tumours Independent of the Tumour Type or Grade

    PubMed Central

    Libard, Sylwia; Popova, Svetlana N.; Amini, Rose-Marie; Kärjä, Vesa; Pietiläinen, Timo; Hämäläinen, Kirsi M.; Sundström, Christer; Hesselager, Göran; Bergqvist, Michael; Ekman, Simon; Zetterling, Maria; Smits, Anja; Nilsson, Pelle; Pfeifer, Susan; de Ståhl, Teresita Diaz; Enblad, Gunilla; Ponten, Fredrik; Alafuzoff, Irina

    2014-01-01

    Human cytomegalovirus (HCMV) has been indicated being a significant oncomodulator. Recent reports have suggested that an antiviral treatment alters the outcome of a glioblastoma. We analysed the performance of commercial HCMV-antibodies applying the immunohistochemical (IHC) methods on brain sample obtained from a subject with a verified HCMV infection, on samples obtained from 14 control subjects, and on a tissue microarray block containing cores of various brain tumours. Based on these trials, we selected the best performing antibody and analysed a cohort of 417 extra- and intra-axial brain tumours such as gliomas, medulloblastomas, primary diffuse large B-cell lymphomas, and meningiomas. HCMV protein pp65 immunoreactivity was observed in all types of tumours analysed, and the IHC expression did not depend on the patient's age, gender, tumour type, or grade. The labelling pattern observed in the tumours differed from the labelling pattern observed in the tissue with an active HCMV infection. The HCMV protein was expressed in up to 90% of all the tumours investigated. Our results are in accordance with previous reports regarding the HCMV protein expression in glioblastomas and medulloblastomas. In addition, the HCMV protein expression was seen in primary brain lymphomas, low-grade gliomas, and in meningiomas. Our results indicate that the HCMV protein pp65 expression is common in intra- and extra-axial brain tumours. Thus, the assessment of the HCMV expression in tumours of various origins and pathologically altered tissue in conditions such as inflammation, infection, and even degeneration should certainly be facilitated. PMID:25268364

  10. MRS water resonance frequency in childhood brain tumours: a novel potential biomarker of temperature and tumour environment

    PubMed Central

    Babourina-Brooks, Ben; Wilson, Martin; Arvanitis, Theodoros N; Peet, Andrew C; Davies, Nigel P

    2014-01-01

    1H MRS thermometry has been investigated for brain trauma and hypothermia monitoring applications but has not been explored in brain tumours. The proton resonance frequency (PRF) of water is dependent on temperature but is also influenced by microenvironment factors, such as fast proton exchange with macromolecules, ionic concentration and magnetic susceptibility. 1H MRS has been utilized for brain tumour diagnostic and prognostic purposes in children; however, the water PRF measure may provide complementary information to further improve characterization. Water PRF values were investigated from a repository of MRS data acquired from childhood brain tumours and children with apparently normal brains. The cohort consisted of histologically proven glioma (22), medulloblastoma (19) and control groups (28, MRS in both the basal ganglia and parietal white matter regions). All data were acquired at 1.5 T using a short TE (30 ms) single voxel spectroscopy (PRESS) protocol. Water PRF values were calculated using methyl creatine and total choline. Spectral peak amplitude weighted averaging was used to improve the accuracy of the measurements. Mean PRF values were significantly larger for medulloblastoma compared with glioma, with a difference in the means of 0.0147 ppm (p < 0.05), while the mean PRF for glioma was significantly lower than for the healthy cohort, with a difference in the means of 0.0061 ppm (p < 0.05). This would suggest the apparent temperature of the glioma group was ?1.5 °C higher than the medulloblastomas and ?0.7 °C higher than a healthy brain. However, the PRF shift may not reflect a change in temperature, given that alterations in protein content, microstructure and ionic concentration contribute to PRF shifts. Measurement of these effects could also be used as a supplementary biomarker, and further investigation is required. This study has shown that the water PRF value has the potential to be used for characterizing childhood brain tumours, which has not been reported previously. © 2014 The Authors. NMR in Biomedicine published by John Wiley & Sons, Ltd. PMID:25125325

  11. Diagnostic segregation of human brain tumours using Fourier-transform infrared and/or Raman spectroscopy coupled with discriminant analysis†

    PubMed Central

    Gajjar, Ketan; Heppenstall, Lara D.; Pang, Weiyi; Ashton, Katherine M.; Trevisan, Júlio; Patel, Imran I.; Llabjani, Valon; Stringfellow, Helen F.; Martin-Hirsch, Pierre L.; Dawson, Timothy; Martin, Francis L.

    2013-01-01

    The most common initial treatment received by patients with a brain tumour is surgical removal of the growth. Precise histopathological diagnosis of brain tumours is to some extent subjective. Furthermore, currently available diagnostic imaging techniques to delineate the excision border during cytoreductive surgery lack the required spatial precision to aid surgeons. We set out to determine whether infrared (IR) and/or Raman spectroscopy combined with multivariate analysis could be applied to discriminate between normal brain tissue and different tumour types (meningioma, glioma and brain metastasis) based on the unique spectral “fingerprints” of their biochemical composition. Formalin-fixed paraffin-embedded tissue blocks of normal brain and different brain tumours were de-waxed, mounted on low-E slides and desiccated before being analyzed using attenuated total reflection Fourier-transform IR (ATR-FTIR) and Raman spectroscopy. ATR-FTIR spectroscopy showed a clear segregation between normal and different tumour subtypes. Discrimination of tumour classes was also apparent with Raman spectroscopy. Further analysis of spectral data revealed changes in brain biochemical structure associated with different tumours. Decreased tentatively-assigned lipid-to-protein ratio was associated with increased tumour progression. Alteration in cholesterol esters-to-phenylalanine ratio was evident in grade IV glioma and metastatic tumours. The current study indicates that IR and/or Raman spectroscopy have the potential to provide a novel diagnostic approach in the accurate diagnosis of brain tumours and have potential for application in intra-operative diagnosis. PMID:24098310

  12. Brain tumours and exposure to pesticides: a case–control study in southwestern France

    PubMed Central

    Provost, Dorothée; Cantagrel, Anne; Lebailly, Pierre; Jaffré, Anne; Loyant, Véronique; Loiseau, Hugues; Vital, Anne; Brochard, Patrick; Baldi, Isabelle

    2007-01-01

    Background Brain tumours are often disabling and rapidly lethal; their aetiology is largely unknown. Among potential risk factors, pesticides are suspected. Objective To examine the relationship between exposure to pesticides and brain tumours in adults in a population‐based case–control study in southwestern France. Methods Between May 1999 and April 2001, 221 incident cases of brain tumours and 442 individually matched controls selected from the general population were enrolled. Histories of occupational and environmental exposures, medical and lifestyle information were collected. A cumulative index of occupational exposure to pesticides was created, based on expert review of lifelong jobs and tasks. Separate analyses were performed for gliomas and meningiomas. Results A non‐statistically significant increase in risk was found for brain tumours when all types of occupational exposure to pesticides were considered (OR = 1.29, 95% CI 0.87 to 1.91) and slightly higher but still non‐statistically significant when gliomas were considered separately (OR = 1.47, 95% CI 0.81 to 2.66). In the highest quartile of the cumulative index, a significant association was found for brain tumours (OR = 2.16, 95% CI 1.10 to 4.23) and for gliomas (OR = 3.21, 95% CI 1.13 to 9.11), but not for meningiomas. A significant increase in risk was also seen for the treatment of home plants (OR = 2.24, 95% CI 1.16 to 4.30) owing to environmental exposure to pesticides. Conclusions These data suggest that a high level of occupational exposure to pesticides might be associated with an excess risk of brain tumours, and especially of gliomas. PMID:17537748

  13. Classification of CT-brain slices based on local histograms

    NASA Astrophysics Data System (ADS)

    Avrunin, Oleg G.; Tymkovych, Maksym Y.; Pavlov, Sergii V.; Timchik, Sergii V.; Kisała, Piotr; Orakbaev, Yerbol

    2015-12-01

    Neurosurgical intervention is a very complicated process. Modern operating procedures based on data such as CT, MRI, etc. Automated analysis of these data is an important task for researchers. Some modern methods of brain-slice segmentation use additional data to process these images. Classification can be used to obtain this information. To classify the CT images of the brain, we suggest using local histogram and features extracted from them. The paper shows the process of feature extraction and classification CT-slices of the brain. The process of feature extraction is specialized for axial cross-section of the brain. The work can be applied to medical neurosurgical systems.

  14. Water transport becomes uncoupled from K+ siphoning in brain contusion, bacterial meningitis, and brain tumours: immunohistochemical case review

    PubMed Central

    Saadoun, S; Papadopoulos, M C; Krishna, S

    2003-01-01

    Specimens of normal human brain, contused brain, brain with bacterial meningitis, and brain tumours were immunolabelled for aquaporin 4 (AQP4) and Kir4.1. In normal brain tissue, AQP4 and Kir4.1 were detected around the microvessels. In pathological brain tissue, AQP4 was upregulated in astrocytes in oedematous regions and Kir4.1 was upregulated in astrocytes in damaged brain. Changes in ? syntrophin expression paralleled those of AQP4 and Kir4.1. The following hypothesis is proposed: in astrocytes, under normal conditions, AQP4 couples water transport with Kir4.1 mediated K+ siphoning, but in pathological states, AQP4 facilitates the flow of brain oedema fluid, and Kir4.1 buffers increased extracellular K+. PMID:14645363

  15. Dietary restriction reduces angiogenesis and growth in an orthotopic mouse brain tumour model

    PubMed Central

    Mukherjee, P; El-Abbadi, M M; Kasperzyk, J L; Ranes, M K; Seyfried, T N

    2002-01-01

    Diet and lifestyle produce major effects on tumour incidence, prevalence, and natural history. Moderate dietary restriction has long been recognised as a natural therapy that improves health, promotes longevity, and reduces both the incidence and growth of many tumour types. Dietary restriction differs from fasting or starvation by reducing total food and caloric intake without causing nutritional deficiencies. No prior studies have evaluated the responsiveness of malignant brain cancer to dietary restriction. We found that a moderate dietary restriction of 30–40% significantly inhibited the intracerebral growth of the CT-2A syngeneic malignant mouse astrocytoma by almost 80%. The total dietary intake for the ad libitum control group (n=9) and the dietary restriction experimental group (n=10) was about 20 and 13?Kcal?day?1, respectively. Overall health and vitality was better in the dietary restriction-fed mice than in the ad libitum-fed mice. Tumour microvessel density (Factor VIII immunostaining) was two-fold less in the dietary restriction mice than in the ad libitum mice, whereas the tumour apoptotic index (TUNEL assay) was three-fold greater in the dietary restriction mice than in the ad libitum mice. CT-2A tumour cell-induced vascularity was also less in the dietary restriction mice than in the ad libitum mice in the in vivo Matrigel plug assay. These findings indicate that dietary restriction inhibited CT-2A growth by reducing angiogenesis and by enhancing apoptosis. Dietary restriction may shift the tumour microenvironment from a proangiogenic to an antiangiogenic state through multiple effects on the tumour cells and the tumour-associated host cells. Our data suggest that moderate dietary restriction may be an effective antiangiogenic therapy for recurrent malignant brain cancers. British Journal of Cancer (2002) 86, 1615–1621. DOI: 10.1038/sj/bjc/6600298 www.bjcancer.com © 2002 Cancer Research UK PMID:12085212

  16. X-ray fluorescence study of the concentration of selected trace and minor elements in human brain tumours

    NASA Astrophysics Data System (ADS)

    Wandzilak, Aleksandra; Czyzycki, Mateusz; Radwanska, Edyta; Adamek, Dariusz; Geraki, Kalotina; Lankosz, Marek

    2015-12-01

    Neoplastic and healthy brain tissues were analysed to discern the changes in the spatial distribution and overall concentration of elements using micro X-ray fluorescence spectroscopy. High-resolution distribution maps of minor and trace elements such as P, S, Cl, K, Ca, Fe, Cu and Zn made it possible to distinguish between homogeneous cancerous tissue and areas where some structures could be identified, such as blood vessels and calcifications. Concentrations of the elements in the selected homogeneous areas of brain tissue were compared between tumours with various malignancy grades and with the controls. The study showed a decrease in the average concentration of Fe, P, S and Ca in tissues with high grades of malignancy as compared to the control group, whereas the concentration of Zn in these tissues was increased. The changes in the concentration were found to be correlated with the tumour malignancy grade. The efficacy of micro X-ray fluorescence spectroscopy to distinguish between various types of cancer based on the concentrations of studied elements was confirmed by multivariate discriminant analysis. Our analysis showed that the most important elements for tissue classification are Cu, K, Fe, Ca, and Zn. This method made it possible to correctly classify histopathological types in 99.93% of the cases used to build the model and in as much as 99.16% of new cases.

  17. Relaxation time based classification of magnetic resonance brain images

    NASA Astrophysics Data System (ADS)

    Baselice, Fabio; Ferraioli, Giampaolo; Pascazio, Vito

    2015-03-01

    Brain tissue classification in Magnetic Resonance Imaging is useful for a wide range of applications. Within this manuscript a novel approach for brain tissue joint segmentation and classification is presented. Starting from the relaxation time estimation, we propose a novel method for identifying the optimal decision regions. The approach exploits the statistical distribution of the involved signals in the complex domain. The technique, compared to classical threshold based ones, is able to improve the correct classification rate. The effectiveness of the approach is evaluated on a simulated case study.

  18. Automatic brain tumour detection and neovasculature assessment with multiseries MRI analysis.

    PubMed

    Szwarc, Pawel; Kawa, Jacek; Rudzki, Marcin; Pietka, Ewa

    2015-12-01

    In this paper a novel multi-stage automatic method for brain tumour detection and neovasculature assessment is presented. First, the brain symmetry is exploited to register the magnetic resonance (MR) series analysed. Then, the intracranial structures are found and the region of interest (ROI) is constrained within them to tumour and peritumoural areas using the Fluid Light Attenuation Inversion Recovery (FLAIR) series. Next, the contrast-enhanced lesions are detected on the basis of T1-weighted (T1W) differential images before and after contrast medium administration. Finally, their vascularisation is assessed based on the Regional Cerebral Blood Volume (RCBV) perfusion maps. The relative RCBV (rRCBV) map is calculated in relation to a healthy white matter, also found automatically, and visualised on the analysed series. Three main types of brain tumours, i.e. HG gliomas, metastases and meningiomas have been subjected to the analysis. The results of contrast enhanced lesions detection have been compared with manual delineations performed independently by two experts, yielding 64.84% sensitivity, 99.89% specificity and 71.83% Dice Similarity Coefficient (DSC) for twenty analysed studies of subjects with brain tumours diagnosed. PMID:26183648

  19. Evaluation of lactate detection using selective multiple quantum coherence in phantoms and brain tumours

    PubMed Central

    Harris, L M; Tunariu, N; Messiou, C; Hughes, J; Wallace, T; DeSouza, N M; Leach, M O; Payne, G S

    2015-01-01

    Lactate is a product of glucose metabolism. In tumour tissues, which exhibit enhanced glycolytic metabolism, lactate signals may be elevated, making lactate a potential useful tumour biomarker. Methods of lactate quantitation are complicated because of overlap between the lactate methyl doublet CH3 resonance and a lipid resonance at 1.3 ppm. This study presents the use of a selective homonuclear multiple quantum coherence transfer sequence (SelMQC-CSI), at 1.5 T, to better quantify lactate in the presence of lipids. Work performed on phantoms showed good lactate detection (49%) and lipid suppression (98%) efficiencies. To evaluate the method in the brain, the sequence was tested on a group of 23 patients with treated brain tumours, either glioma (N = 20) or secondary metastases in the brain (N = 3). Here it was proved to be of use in determining lactate concentrations in vivo. Lactate was clearly seen in SelMQC spectra of glioma, even in the presence of lipids, with high grade glioma (7.3 ± 1.9 mM, mean ± standard deviation) having higher concentrations than low grade glioma (1.9 ± 1.5 mM, p = 0.048). Lactate was not seen in secondary metastases in the brain. SelMQC-CSI is shown to be a useful technique for measuring lactate in tumours whose signals are otherwise contaminated by lipid. © 2015 The Authors NMR in Biomedicine Published by John Wiley & Sons Ltd. PMID:25586623

  20. Radiosensitisation of U87MG brain tumours by anti-epidermal growth factor receptor monoclonal antibodies

    PubMed Central

    Diaz Miqueli, A; Rolff, J; Lemm, M; Fichtner, I; Perez, R; Montero, E

    2009-01-01

    As epidermal growth factor receptor (EGFR) has been reported to be a radiation response modulator, HER inhibitors are regarded to act as potential radiosensitisers. Our study examined the role of nimotuzumab and cetuximab both, the two monoclonal antibodies (mAbs) to EGFR, as radiosensitisers in a murine glioma model in vivo. Co-administration of both the antibodies with radiation increased the radiosensitivity of U87MG, resulting in a significant delay of subcutaneous (s.c.) tumour growth. Furthermore, the addition of antibodies to the radiation decreased brain tumour sizes and is inhibited by 40–80% the increased tumour cell invasion provoked by radiotherapy, although promoted tumour cell apoptosis. Whereas nimotuzumab led to a reduction in the size of tumour blood vessels and proliferating cells in s.c. tumours, cetuximab had no significant antiangiogenic nor antiproliferative activity. In contrast, cetuximab induced a more marked inhibition of EGFR downstream signalling compared with nimotuzumab. Moreover, both antibodies reduced the total number of radioresistant CD133+ cancer stem cells (CSCs). These results were encouraging, and showed the superiority of combined treatment of mAbs to EGFR and radiation over each single therapy against glioblastoma multiforme (GBM), confirming the role of these drugs as radiosensitisers in human GBM. In addition, we first showed the ability of mAb specifics against EGFR to target radioresistant glioma CSC, supporting the potential use in patients. PMID:19293809

  1. Photodynamic therapy of malignant brain tumours: a complementary approach to conventional therapies.

    PubMed

    Bechet, Denise; Mordon, Serge R; Guillemin, François; Barberi-Heyob, Muriel A

    2014-03-01

    The poor outcome of primary malignant brain tumours is predominantly due to local invasion and local recurrence and their prognosis is highly dependent on the degree of resection. They have no border and, at best, a marginal zone that remains invisible to the surgeon. Photodynamic therapy (PDT) appears to be an interesting modality to fill the need for a targeted treatment that may reduce recurrence and extend survival with minimal side effects. In this review, we summarize the different technologies of brain tumour PDT employed such as interstitial PDT, and PDT-associated surgical resection, describing new light delivery devices. The role of dosimetry - one of the key factors behind successful brain tumour PDT - is discussed. This can be achieved by integrating results from in vivo studies. In this context, the development of new therapeutic photosensitizer delivery systems is also an area of significant research interest. Multifunctionality can be engineered into a single nanoplatform to provide tumour-specific detection, treatment, and follow-up. Such multitasking systems appear to be complementary to conventional technologies. PMID:22858248

  2. Simple Fully Automated Group Classification on Brain fMRI

    SciTech Connect

    Honorio, J.; Goldstein, R.; Honorio, J.; Samaras, D.; Tomasi, D.; Goldstein, R.Z.

    2010-04-14

    We propose a simple, well grounded classification technique which is suited for group classification on brain fMRI data sets that have high dimensionality, small number of subjects, high noise level, high subject variability, imperfect registration and capture subtle cognitive effects. We propose threshold-split region as a new feature selection method and majority voteas the classification technique. Our method does not require a predefined set of regions of interest. We use average acros ssessions, only one feature perexperimental condition, feature independence assumption, and simple classifiers. The seeming counter-intuitive approach of using a simple design is supported by signal processing and statistical theory. Experimental results in two block design data sets that capture brain function under distinct monetary rewards for cocaine addicted and control subjects, show that our method exhibits increased generalization accuracy compared to commonly used feature selection and classification techniques.

  3. Transient Global Amnesia and Brain Tumour: Chance Concurrence or Aetiological Association? Case Report and Systematic Literature Review

    PubMed Central

    Milburn-McNulty, Phil; Larner, Andrew J.

    2015-01-01

    We report a patient presenting with episodes of transient amnesia, some with features suggestive of transient global amnesia (TGA), and some more reminiscent of transient epileptic amnesia. Investigation with neuroimaging revealed an intrinsic lesion in the right amygdala, with features suggestive of low-grade neoplasia. We undertook a systematic review of the literature on TGA and brain tumour. Fewer than 20 cases were identified, some of which did not conform to the clinical diagnostic criteria for TGA. Hence, the concurrence of brain tumour and TGA is very rare and of doubtful aetiological relevance. In some brain tumour-associated cases, epilepsy may be masquerading as TGA. PMID:25802501

  4. The sensitivity of normal brain and intracranially implanted VX2 tumour to interstitial photodynamic therapy.

    PubMed Central

    Lilge, L.; Olivo, M. C.; Schatz, S. W.; MaGuire, J. A.; Patterson, M. S.; Wilson, B. C.

    1996-01-01

    The applicability and limitations of a photodynamic threshold model, used to describe quantitatively the in vivo response of tissues to photodynamic therapy, are currently being investigated in a variety of normal and malignant tumour tissues. The model states that tissue necrosis occurs when the number of photons absorbed by the photosensitiser per unit tissue volume exceeds a threshold. New Zealand White rabbits were sensitised with porphyrin-based photosensitisers. Normal brain or intracranially implanted VX2 tumours were illuminated via an optical fibre placed into the tissue at craniotomy. The light fluence distribution in the tissue was measured by multiple interstitial optical fibre detectors. The tissue concentration of the photosensitiser was determined post mortem by absorption spectroscopy. The derived photodynamic threshold values for normal brain are significantly lower than for VX2 tumour for all photosensitisers examined. Neuronal damage is evident beyond the zone of frank necrosis. For Photofrin the threshold decreases with time delay between photosensitiser administration and light treatment. No significant difference in threshold is found between Photofrin and haematoporphyrin derivative. The threshold in normal brain (grey matter) is lowest for sensitisation by 5 delta-aminolaevulinic acid. The results confirm the very high sensitivity of normal brain to porphyrin photodynamic therapy and show the importance of in situ light fluence monitoring during photodynamic irradiation. Images Figure 1 Figure 4 Figure 5 Figure 6 Figure 7 PMID:8562339

  5. Plumbagin alters telomere dynamics, induces DNA damage and cell death in human brain tumour cells.

    PubMed

    Khaw, Aik Kia; Sameni, Safoura; Venkatesan, Shriram; Kalthur, Guruprasad; Hande, M Prakash

    2015-11-01

    Natural plant products may possess much potential in palliative therapy and supportive strategies of current cancer treatments with lesser cytotoxicity to normal cells compared to conventional chemotherapy. In the current study, anti-cancer properties of plumbagin, a plant-derived naphthoquinone, on brain cancer cells were determined. Plumbagin treatment resulted in the induction of DNA damage, cell cycle arrest and apoptosis, followed by suppression of the colony forming ability of the brain tumour cells. These effects were substantiated by upregulation of PTEN, TNFRSF1A and downregulation of E2F1 genes, along with a drop in MDM2, cyclin B1, survivin and BCL2 protein expression. Plumbagin induced elevated levels of caspase-3/7 activity as well. For the first time, we show here that plumbagin inhibits telomerase in brain tumour cells and results in telomere shortening following chronic long-term treatment. This observation implies considerable cytotoxicity of plumbagin towards cancer cells with higher telomerase activity. Collectively, our findings suggest plumbagin as a potential chemotherapeutic phytochemical in brain tumour treatment modalities. PMID:26520377

  6. Occupational exposure to extremely low frequency magnetic fields and brain tumour risks in the INTEROCC study

    PubMed Central

    Turner, Michelle C; Benke, Geza; Bowman, Joseph D; Figuerola, Jordi; Fleming, Sarah; Hours, Martine; Kincl, Laurel; Krewski, Daniel; McLean, Dave; Parent, Marie-Elise; Richardson, Lesley; Sadetzki, Siegal; Schlaefer, Klaus; Schlehofer, Brigitte; Schüz, Joachim; Siemiatycki, Jack; van Tongeren, Martie; Cardis, Elisabeth

    2014-01-01

    Background Occupational exposure to extremely low frequency magnetic fields (ELF) is a suspected risk factor for brain tumours, however the literature is inconsistent. Few studies have assessed whether ELF in different time windows of exposure may be associated with specific histologic types of brain tumours. This study examines the association between ELF and brain tumours in the large-scale INTEROCC study. Methods Cases of adult primary glioma and meningioma were recruited in seven countries (Australia, Canada, France, Germany, Israel, New Zealand, United Kingdom) between 2000 and 2004. Estimates of mean workday ELF exposure based on a job exposure matrix assigned. Estimates of cumulative exposure, average exposure, maximum exposure, and exposure duration were calculated for the lifetime, and 1–4, 5–9, and 10+ years prior to the diagnosis/reference date. Results There were 3,761 included brain tumour cases (1,939 glioma, 1,822 meningioma) and 5,404 population controls. There was no association between lifetime cumulative ELF exposure and glioma or meningioma risk. However, there were positive associations between cumulative ELF 1–4 years prior to the diagnosis/reference date and glioma (odds ratio (OR) ? 90th percentile vs < 25th percentile = 1.67, 95% confidence interval (CI) 1.36–2.07, p < 0.0001 linear trend), and, somewhat weaker associations with meningioma (OR ? 90th percentile vs < 25th percentile = 1.23, 95% CI 0.97–1.57, p = 0.02 linear trend). Conclusions Results showed positive associations between ELF in the recent past and glioma. Impact Occupational ELF exposure may play a role in the later stages (promotion and progression) of brain tumourigenesis. PMID:24935666

  7. Development of a positron probe for localization and excision of brain tumours during surgery.

    PubMed

    Bogalhas, F; Charon, Y; Duval, M-A; Lefebvre, F; Palfi, S; Pinot, L; Siebert, R; Ménard, L

    2009-07-21

    The survival outcome of patients suffering from gliomas is directly linked to the complete surgical resection of the tumour. To help the surgeons to delineate precisely the boundaries of the tumour, we developed an intraoperative positron probe with background noise rejection capability. The probe was designed to be directly coupled to the excision tool such that detection and removal of the radiolabelled tumours could be simultaneous. The device consists of two exchangeable detection heads composed of clear and plastic scintillating fibres. Each head is coupled to an optic fibre bundle that exports the scintillating light to a photodetection and processing electronic module placed outside the operative wound. The background rejection method is based on a real-time subtraction technique. The measured probe sensitivity for (18)F was 1.1 cps kBq(-1) ml(-1) for the small head and 3.4 cps kBq(-1) ml(-1) for the large head. The mean spatial resolution was 1.6 mm FWHM on the detector surface. The gamma-ray rejection efficiency measured by realistic brain phantom modelling of the surgical cavity was 99.4%. This phantom also demonstrated the ability of the probe to detect tumour discs as small as 5 mm in diameter (20 mg) for tumour-to-background ratios higher than 3:1 and with an acquisition time around 4 s at each scanning step. These results indicate that our detector could be a useful complement to existing techniques for the accurate excision of brain tumour tissue and more generally to improve the efficiency of radio-guided cancer surgery. PMID:19556688

  8. Development of a positron probe for localization and excision of brain tumours during surgery

    NASA Astrophysics Data System (ADS)

    Bogalhas, F.; Charon, Y.; Duval, M.-A.; Lefebvre, F.; Palfi, S.; Pinot, L.; Siebert, R.; Ménard, L.

    2009-07-01

    The survival outcome of patients suffering from gliomas is directly linked to the complete surgical resection of the tumour. To help the surgeons to delineate precisely the boundaries of the tumour, we developed an intraoperative positron probe with background noise rejection capability. The probe was designed to be directly coupled to the excision tool such that detection and removal of the radiolabelled tumours could be simultaneous. The device consists of two exchangeable detection heads composed of clear and plastic scintillating fibres. Each head is coupled to an optic fibre bundle that exports the scintillating light to a photodetection and processing electronic module placed outside the operative wound. The background rejection method is based on a real-time subtraction technique. The measured probe sensitivity for 18F was 1.1 cps kBq-1 ml-1 for the small head and 3.4 cps kBq-1 ml-1 for the large head. The mean spatial resolution was 1.6 mm FWHM on the detector surface. The ?-ray rejection efficiency measured by realistic brain phantom modelling of the surgical cavity was 99.4%. This phantom also demonstrated the ability of the probe to detect tumour discs as small as 5 mm in diameter (20 mg) for tumour-to-background ratios higher than 3:1 and with an acquisition time around 4 s at each scanning step. These results indicate that our detector could be a useful complement to existing techniques for the accurate excision of brain tumour tissue and more generally to improve the efficiency of radio-guided cancer surgery.

  9. Inference of brain pathway activities for Alzheimer's disease classification

    PubMed Central

    2015-01-01

    Background Alzheimer's disease (AD) is a neurodegenerative and progressive disorder that results in brain malfunctions. Resting-state (RS) functional magnetic resonance imaging (fMRI) techniques have been successfully applied for quantifying brain activities of both Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI) patients. Region-based approaches are widely utilized to classify patients from cognitively normal subjects (CN). Nevertheless, region-based approaches have a few limitations, reproducibility owing to selection of disease-specific brain regions, and heterogeneity of brain activities during disease progression. For coping with these issues, network-based approaches have been suggested in the field of molecular bioinformatics. In comparison with individual gene-based approaches, they acquired more accurate results in diverse disease classification, and reproducibility was confirmed by replication studies. In our work, we applied a similar methodology integrating brain pathway information into pathway activity inference, and permitting classification of both aMCI and AD patients based on pathway activities rather than single region activities. Results After aggregating the 59 brain pathways from literature, we estimated brain pathway activities by using exhaustive search algorithms between patients and cognitively normal subjects, and identified discriminatory pathways according to disease progression. We used three different data sets and each data set consists of two different groups. Our results show that the pathway-based approach (AUC = 0.89, 0.9, 0.75) outperformed the region-based approach (AUC = 0.69, 0.8, 0.68). Also, our approach provided enhanced diagnostic power achieving higher accuracy, sensitivity, and specificity (pathway-based approach: accuracy = 83%; sensitivity = 86%; specificity = 78%, region-based approach: accuracy = 74%; sensitivity = 78%; specificity = 76%). Conclusions We proposed a novel method inferring brain pathway activities for disease classification. Our approach shows better classification performance than region-based approach in four classification models. We expect that brain pathway-based approach would be helpful for precise classification of brain disorders, and provide new opportunities for uncovering disrupted brain pathways caused by disease. Moreover, discriminatory pathways between patients and cognitively normal subjects may facilitate the interpretation of functional alterations during disease progression. PMID:26044913

  10. Short- and long-term outcomes of endoscopic resection of rectal neuroendocrine tumours: analyses according to the WHO 2010 classification.

    PubMed

    Nakamura, Kazuhiko; Osada, Mikako; Goto, Ayako; Iwasa, Tsutomu; Takahashi, Shunsuke; Takizawa, Nobuyoshi; Akahoshi, Kazuya; Ochiai, Toshiaki; Nakamura, Norimoto; Akiho, Hirotada; Itaba, Soichi; Harada, Naohiko; Iju, Moritomo; Tanaka, Munehiro; Kubo, Hiroaki; Somada, Shinichi; Ihara, Eikichi; Oda, Yoshinao; Ito, Tetsuhide; Takayanagi, Ryoichi

    2016-04-01

    Objective Although the World Health Organisation (WHO) defined a novel classification of gastroenteropancreatic neuroendocrine tumours (NETs) in 2010, indications for endoscopic resection of rectal NETs in the guidelines were based on evidence accumulated for carcinoid tumours defined by a previous classification. This study was designed to clarify indications for endoscopic resection of rectal NETs corresponding to the new WHO classifications. Material and methods One hundred-seventy rectal NETs resected endoscopically from April 2001 to March 2012 were histologically re-classified according to the WHO 2010 criteria. The clinicopathological features of these lesions were analysed, and the short- and long-term outcomes of endoscopic resection were evaluated. Results Of the 170 rectal NETs, 166 were histopathologically diagnosed as NET G1 and four as NET G2. Thirty-eight tumours (22.4%) were positive for lymphovascular invasion, a percentage higher than expected. Although the curative resection rate was low (65.3%), en bloc (98.8%) and complete (85.9%) resection rates were high. Modified endoscopic mucosal resection (88.0%) and endoscopic submucosal dissection (92.2%) resulted in significantly higher complete resection rates than conventional endoscopic mucosal resection (36.4%). No patient experienced tumour recurrence, despite the low curative resection rate. Conclusion Despite the low curative resection rate, prognosis after endoscopic resection of rectal NETs was excellent. Prospective large-scale, long-term studies are required to determine whether NET G2 and tumours >1?cm should be included in the indication for endoscopic resection and whether tumours with lymphovascular invasion can be followed up without additional surgery. PMID:26540372

  11. Three validation metrics for automated probabilistic image segmentation of brain tumours

    PubMed Central

    Zou, Kelly H.; Wells, William M.; Kikinis, Ron; Warfield, Simon K.

    2005-01-01

    SUMMARY The validity of brain tumour segmentation is an important issue in image processing because it has a direct impact on surgical planning. We examined the segmentation accuracy based on three two-sample validation metrics against the estimated composite latent gold standard, which was derived from several experts’ manual segmentations by an EM algorithm. The distribution functions of the tumour and control pixel data were parametrically assumed to be a mixture of two beta distributions with different shape parameters. We estimated the corresponding receiver operating characteristic curve, Dice similarity coefficient, and mutual information, over all possible decision thresholds. Based on each validation metric, an optimal threshold was then computed via maximization. We illustrated these methods on MR imaging data from nine brain tumour cases of three different tumour types, each consisting of a large number of pixels. The automated segmentation yielded satisfactory accuracy with varied optimal thresholds. The performances of these validation metrics were also investigated via Monte Carlo simulation. Extensions of incorporating spatial correlation structures using a Markov random field model were considered. PMID:15083482

  12. Validation of IR-spectroscopic brain tumor classification

    NASA Astrophysics Data System (ADS)

    Beleites, C.; Steiner, G.; Sobottka, S.; Schackert, G.; Salzer, R.

    2006-02-01

    As a molecular probe of tissue composition, infrared spectroscopic imaging serves as an adjunct to histopathology in detecting and diagnosing disease. In the past it was demonstrated that the IR spectra of brain tumors can be discriminated from one another according to their grade of malignancy. Although classification success rates up to 93% were observed one problem consists in the variation of the models depending on the number of samples used for the development of the classification model. In order to open the path for clinical trials the classification has to be validated. A series of classification models were built using a k-fold cross validation scheme and the classification predictions from the various models were combined to provide an aggregated prediction. The validation highlights instabilities in the models, error rates, sensitivity as well as specificity of the classification and allows the determination of confidence intervals. Better classification models could be achieved by an aggregated prediction. The validation shows that brain tumors can be classified by infrared spectroscopy and the grade of malignancy corresponds reasonably to the histopathological assignment.

  13. Childhood brain tumour risk and its association with wireless phones: a commentary.

    PubMed

    Söderqvist, Fredrik; Carlberg, Michael; Hansson Mild, Kjell; Hardell, Lennart

    2011-01-01

    Case-control studies on adults point to an increased risk of brain tumours (glioma and acoustic neuroma) associated with the long-term use of mobile phones. Recently, the first study on mobile phone use and the risk of brain tumours in children and adolescents, CEFALO, was published. It has been claimed that this relatively small study yielded reassuring results of no increased risk. We do not agree. We consider that the data contain several indications of increased risk, despite low exposure, short latency period, and limitations in the study design, analyses and interpretation. The information certainly cannot be used as reassuring evidence against an association, for reasons that we discuss in this commentary. PMID:22182218

  14. Neural correlates of delayed visual-motor performance in children treated for brain tumours.

    PubMed

    Dockstader, Colleen; Gaetz, William; Bouffet, Eric; Tabori, Uri; Wang, Frank; Bostan, Stefan R; Laughlin, Suzanne; Mabbott, Donald J

    2013-09-01

    Both structural and functional neural integrity is critical for healthy cognitive function and performance. Across studies, it is evident that children who are affected by neurological insult commonly demonstrate impaired cognitive abilities. Children treated with cranial radiation for brain tumours suffer substantial structural damage and exhibit a particularly high correlation between the degree of neural injury and cognitive deficits. However the pathophysiology underlying impaired cognitive performance in this population, and many other paediatric populations affected by neurological injury or disease, is unknown. We wished to investigate the characteristics of neuronal function during visual-motor task performance in a group of children who were treated with cranial radiation for brain tumours. We used Magnetoencephalography to investigate neural function during visual-motor reaction time (RT) task performance in 15 children treated with cranial radiation for Posterior Fossa malignant brain tumours and 17 healthy controls. We found that, relative to controls, the patient group showed: 1) delayed latencies for neural activation in both visual and motor cortices; 2) muted motor responses in the alpha (8-12Hz) and beta (13-29Hz) bandwidths, and 3) potentiated visual and motor responses in the gamma (30-100Hz) bandwidth. Collectively these observations indicate impaired neural processing during visual-motor RT performance in this population and that delays in the speed of visual and motor neuronal processing both contribute to the delays in the behavioural response. As increases in gamma activity are often observed with increases in attention and effort, increased gamma activities in the patient group may reflect compensatory neural activity during task performance. This is the first study to investigate neural function in real-time during cognitive performance in paediatric brain tumour patients. PMID:23102743

  15. Classification of brain tumors using MRI and MRS data

    NASA Astrophysics Data System (ADS)

    Wang, Qiang; Liacouras, Eirini Karamani; Miranda, Erickson; Kanamalla, Uday S.; Megalooikonomou, Vasileios

    2007-03-01

    We study the problem of classifying brain tumors as benign or malignant using information from magnetic resonance (MR) imaging and magnetic resonance spectroscopy (MRS) to assist in clinical diagnosis. The proposed approach consists of several steps including segmentation, feature extraction, feature selection, and classification model construction. Using an automated segmentation technique based on fuzzy connectedness we accurately outline the tumor mass boundaries in the MR images so that further analysis concentrates on these regions of interest (ROIs). We then apply a concentric circle technique on the ROIs to extract features that are utilized by the classification algorithms. To remove redundant features, we perform feature selection where only those features with discriminatory information (among classes) are used in the model building process. The involvement of MRS features further improves the classification accuracy of the model. Experimental results demonstrate the effectiveness of the proposed approach in classifying brain tumors in MR images.

  16. Brain MRI Tissue Classification Based on Local Markov Random Fields

    PubMed Central

    Dinov, Ivo D.; Shattuck, David W.; Toga, Arthur W.

    2010-01-01

    A new method for tissue classification of brain magnetic resonance images (MRI) of the brain is proposed. The method is based on local image models where each models the image content in a subset of the image domain. With this local modeling approach, the assumption that tissue types have the same characteristics over the brain needs not to be evoked. This is important because tissue type characteristics, such as T1 and T2 relaxation times and proton density, vary across the individual brain and the proposed method offers improved protection against intensity non-uniformity artifacts that can hamper automatic tissue classification methods in brain MRI. A framework in which local models for tissue intensities and Markov Random Field priors are combined into a global probabilistic image model is introduced. This global model will be an inhomogeneous Markov Random Field and it can be solved by standard algorithms such as iterative conditional modes. The division of the whole image domain into local brain regions possibly having different intensity statistics is realized via sub-volume probabilistic atlases. Finally, the parameters for the local intensity models are obtained without supervision by maximizing the weighted likelihood of a certain finite mixture model. For the maximization task, a novel genetic algorithm almost free of initialization dependency is applied. The algorithm is tested on both simulated and real brain MR images. The experiments confirm that the new method offers a useful improvement of the tissue classification accuracy when the basic tissue characteristics vary across the brain and the noise level of the images is reasonable. The method also offers better protection against intensity non-uniformity artifact than the corresponding method based on a global (whole image) modeling scheme. PMID:20110151

  17. Brain MRI tissue classification based on local Markov random fields.

    PubMed

    Tohka, Jussi; Dinov, Ivo D; Shattuck, David W; Toga, Arthur W

    2010-05-01

    A new method for tissue classification of brain magnetic resonance images (MRI) of the brain is proposed. The method is based on local image models where each models the image content in a subset of the image domain. With this local modeling approach, the assumption that tissue types have the same characteristics over the brain needs not to be evoked. This is important because tissue type characteristics, such as T1 and T2 relaxation times and proton density, vary across the individual brain and the proposed method offers improved protection against intensity non-uniformity artifacts that can hamper automatic tissue classification methods in brain MRI. A framework in which local models for tissue intensities and Markov Random Field (MRF) priors are combined into a global probabilistic image model is introduced. This global model will be an inhomogeneous MRF and it can be solved by standard algorithms such as iterative conditional modes. The division of the whole image domain into local brain regions possibly having different intensity statistics is realized via sub-volume probabilistic atlases. Finally, the parameters for the local intensity models are obtained without supervision by maximizing the weighted likelihood of a certain finite mixture model. For the maximization task, a novel genetic algorithm almost free of initialization dependency is applied. The algorithm is tested on both simulated and real brain MR images. The experiments confirm that the new method offers a useful improvement of the tissue classification accuracy when the basic tissue characteristics vary across the brain and the noise level of the images is reasonable. The method also offers better protection against intensity non-uniformity artifact than the corresponding method based on a global (whole image) modeling scheme. PMID:20110151

  18. Combined therapies of antithrombotics and antioxidants delay in silico brain tumour progression.

    PubMed

    Martínez-González, Alicia; Durán-Prado, Mario; Calvo, Gabriel F; Alcaín, Francisco J; Pérez-Romasanta, Luis A; Pérez-García, Víctor M

    2015-09-01

    Glioblastoma multiforme (GBM), the most frequent type of primary brain tumour, is a rapidly evolving and spatially heterogeneous high-grade astrocytoma that presents areas of necrosis, hypercellularity and microvascular hyperplasia. The aberrant vasculature leads to hypoxic areas and results in an increase in oxidative stress, selecting for more invasive tumour cell phenotypes. In our study, we assay in silico different therapeutic approaches which combine antithrombotics (ATs), antioxidants and standard radiotherapy (RT). To do so, we have developed a biocomputational model of GBM that incorporates the spatio-temporal interplay among two glioma cell phenotypes corresponding to oxygenated and hypoxic cells, a necrotic core and the local vasculature whose response evolves with tumour progression. Our numerical simulations predict that suitable combinations of ATs and antioxidants may diminish, in a synergistic way, oxidative stress and the subsequent hypoxic response. This novel therapeutical strategy, with potentially low or no toxicity, might reduce tumour invasion and further sensitize GBM to conventional RT or other cytotoxic agents, hopefully increasing median patient overall survival time. PMID:24562299

  19. Classification of Traumatic Brain Injury for Targeted Therapies

    PubMed Central

    Saatman, Kathryn E.; Duhaime, Ann-Christine; Bullock, Ross; Maas, Andrew I.R.; Valadka, Alex

    2008-01-01

    Abstract The heterogeneity of traumatic brain injury (TBI) is considered one of the most significant barriers to finding effective therapeutic interventions. In October, 2007, the National Institute of Neurological Disorders and Stroke, with support from the Brain Injury Association of America, the Defense and Veterans Brain Injury Center, and the National Institute of Disability and Rehabilitation Research, convened a workshop to outline the steps needed to develop a reliable, efficient and valid classification system for TBI that could be used to link specific patterns of brain and neurovascular injury with appropriate therapeutic interventions. Currently, the Glasgow Coma Scale (GCS) is the primary selection criterion for inclusion in most TBI clinical trials. While the GCS is extremely useful in the clinical management and prognosis of TBI, it does not provide specific information about the pathophysiologic mechanisms which are responsible for neurological deficits and targeted by interventions. On the premise that brain injuries with similar pathoanatomic features are likely to share common pathophysiologic mechanisms, participants proposed that a new, multidimensional classification system should be developed for TBI clinical trials. It was agreed that preclinical models were vital in establishing pathophysiologic mechanisms relevant to specific pathoanatomic types of TBI and verifying that a given therapeutic approach improves outcome in these targeted TBI types. In a clinical trial, patients with the targeted pathoanatomic injury type would be selected using an initial diagnostic entry criterion, including their severity of injury. Coexisting brain injury types would be identified and multivariate prognostic modeling used for refinement of inclusion/exclusion criteria and patient stratification. Outcome assessment would utilize endpoints relevant to the targeted injury type. Advantages and disadvantages of currently available diagnostic, monitoring, and assessment tools were discussed. Recommendations were made for enhancing the utility of available or emerging tools in order to facilitate implementation of a pathoanatomic classification approach for clinical trials. PMID:18627252

  20. Brain metastasis in renal cancer patients: metastatic pattern, tumour-associated macrophages and chemokine/chemoreceptor expression

    PubMed Central

    Wyler, L; Napoli, C U; Ingold, B; Sulser, T; Heikenwälder, M; Schraml, P; Moch, H

    2014-01-01

    Background: The mechanisms of brain metastasis in renal cell cancer (RCC) patients are poorly understood. Chemokine and chemokine receptor expression may contribute to the predilection of RCC for brain metastasis by recruitment of monocytes/macrophages and by control or induction of vascular permeability of the blood–brain barrier. Methods: Frequency and patterns of brain metastasis were determined in 246 patients with metastatic RCC at autopsy. Expression of CXCR4, CCL7 (MCP-3), CCR2 and CD68+ tumour-associated macrophages (TAMs) were analysed in a separate series of 333 primary RCC and in 48 brain metastases using immunohistochemistry. Results: Fifteen percent of 246 patients with metastasising RCC had brain metastasis. High CXCR4 expression levels were found in primary RCC and brain metastases (85.7% and 91.7%, respectively). CCR2 (52.1%) and CCL7 expression (75%) in cancer cells of brain metastases was more frequent compared with primary tumours (15.5% and 16.7%, respectively; P<0.0001 each). The density of CD68+ TAMs was similar in primary RCC and brain metastases. However, TAMs were more frequently CCR2-positive in brain metastases than in primary RCC (P<0.001). Conclusion: Our data demonstrate that the monocyte-specific chemokine CCL7 and its receptor CCR2 are expressed in tumour cells of RCC. We conclude that monocyte recruitment by CCR2 contributes to brain metastasis of RCC. PMID:24327013

  1. The brain MRI classification problem from wavelets perspective

    NASA Astrophysics Data System (ADS)

    Bendib, Mohamed M.; Merouani, Hayet F.; Diaba, Fatma

    2015-02-01

    Haar and Daubechies 4 (DB4) are the most used wavelets for brain MRI (Magnetic Resonance Imaging) classification. The former is simple and fast to compute while the latter is more complex and offers a better resolution. This paper explores the potential of both of them in performing Normal versus Pathological discrimination on the one hand, and Multiclassification on the other hand. The Whole Brain Atlas is used as a validation database, and the Random Forest (RF) algorithm is employed as a learning approach. The achieved results are discussed and statistically compared.

  2. Childhood brain tumours and use of mobile phones: comparison of a case-control study with incidence data.

    PubMed

    Aydin, Denis; Feychting, Maria; Schüz, Joachim; Röösli, Martin

    2012-01-01

    The first case-control study on mobile phone use and brain tumour risk among children and adolescents (CEFALO study) has recently been published. In a commentary published in Environmental Health, Söderqvist and colleagues argued that CEFALO suggests an increased brain tumour risk in relation to wireless phone use. In this article, we respond and show why consistency checks of case-control study results with observed time trends of incidence rates are essential, given the well described limitations of case-control studies and the steep increase of mobile phone use among children and adolescents during the last decade. There is no plausible explanation of how a notably increased risk from use of wireless phones would correspond to the relatively stable incidence time trends for brain tumours among children and adolescents observed in the Nordic countries. Nevertheless, an increased risk restricted to heavy mobile phone use, to very early life exposure, or to rare subtypes of brain tumours may be compatible with stable incidence trends at this time and thus further monitoring of childhood brain tumour incidence rate time trends is warranted. PMID:22607537

  3. What are the experiences of the child with a brain tumour and their parents?

    PubMed

    Soanes, Louise; Hargrave, Darren; Smith, Lauren; Gibson, Faith

    2009-09-01

    Brain tumours are one of the most common forms of childhood cancer, affecting approximately 350 children in the UK each year (CancerBackup, 2005). The complex and long treatment for such tumours is often delivered in more than one place of care, as a result children and their families meet a large number of healthcare professionals from a variety of disciplines. The study described in this paper was undertaken to explore the experiences of children/young people (C/YP) with a brain tumour (and their families) being treated at a NHS Trust. A longitudinal, exploratory and descriptive case study was undertaken, using multiple methods of data collection. Three age appropriate data collection techniques were used with children; a modified Mosaic Approach (Clark and Moss, 2001) for children 4-6 years; the 'draw and write technique' with children aged 6-12 year olds, children over 12 years old were interviewed. Semi-structured interviews were also undertaken with parents. Ten children aged 4-13 years, nine mothers and nine fathers took part in the study. Data were analysed using the process described by Ritchie and Spencer (1994). Four themes are identified, receiving and seeking information, finding your way through, how life is affected, who and what help? The process of receiving and seeking information was a challenge for both parents and children. Age appropriate environment and activities helped with adjustment and boredom during long waits and treatment. The need for support from one individual to help families find their way through the complexity of healthcare was a persistent theme. Insights into what children and their parents value from the services offered and areas that they as users find challenging were identified from this study and the findings have implications for future practice and service provision. PMID:19423391

  4. No evidence for germline PTEN mutations in families with breast and brain tumours.

    PubMed

    Laugé, A; Lefebvre, C; Laurent-Puig, P; Caux, V; Gad, S; Eng, C; Longy, M; Stoppa-Lyonnet, D

    1999-06-21

    Germline mutations of the PTEN gene are involved in Cowden disease, a genetic condition associated with an increased risk of breast cancer. Further somatic PTEN mutations have been found in glioblastomas and to a lesser extent in meningiomas. Therefore, PTEN germline mutations were searched for in a series of 20 unrelated women with breast cancer who also had a personal or familial breast-brain tumour history. Inclusion criteria were 1. family history of breast cancer; 2. absence of germline BRCA1 and p53 mutation; and 3. at least one case of brain tumour (glioblastoma, meningioma, or medulloblastoma) in either the index case or one of their first or second degree relatives. Any stigmata of Cowden disease was an exclusion criteria. Screening of the PTEN gene for point mutations or small rearrangements were performed using the denaturing gradient gel electrophoresis method on the 9 coding exons. No disease-associated mutation of the PTEN gene has been detected in our series. It is, thus, unlikely that PTEN is a significant BRCA predisposing locus. However, one might ask whether breast cancer cases resulting from germline PTEN mutation could occur without any mammary histological feature of Cowden disease. PMID:10371336

  5. Image-guided microbeam irradiation to brain tumour bearing mice using a carbon nanotube X-ray source array

    PubMed Central

    Zhang, Lei; Yuan, Hong; Burk, Laurel M; Inscoe, Christy R; Hadsell, Michael J; Chtcheprov, Pavel; Lee, Yueh Z; Lu, Jianping; Chang, Sha; Zhou, Otto

    2014-01-01

    Microbeam radiation therapy (MRT) is a promising experimental and preclinical radiotherapy method for cancer treatment. Synchrotron based MRT experiments have shown that spatially fractionated microbeam radiation has the unique capability of preferentially eradicating tumour cells while sparing normal tissue in brain tumour bearing animal models. We recently demonstrated the feasibility of generating orthovoltage microbeam radiation with an adjustable microbeam width using a carbon nanotube based X-ray source array. Here we report the preliminary results from our efforts in developing an image guidance procedure for the targeted delivery of the narrow microbeams to the small tumour region in the mouse brain. Magnetic resonance imaging was used for tumour identification, and on-board X-ray radiography was used for imaging of landmarks without contrast agents. The two images were aligned using 2D rigid body image registration to determine the relative position of the tumour with respect to a landmark. The targeting accuracy and consistency were evaluated by first irradiating a group of mice inoculated with U87 human glioma brain tumours using the present protocol and then determining the locations of the microbeam radiation tracks using γ-H2AX immunofluorescence staining. The histology results showed that among 14 mice irradiated, 11 received the prescribed number of microbeams on the targeted tumour, with an average localization accuracy of 454 μm measured directly from the histology (537 μm if measured from the registered histological images). Two mice received one of the three prescribed microbeams on the tumour site. One mouse was excluded from the analysis due to tissue staining errors. PMID:24556798

  6. Image-guided microbeam irradiation to brain tumour bearing mice using a carbon nanotube x-ray source array

    NASA Astrophysics Data System (ADS)

    Zhang, Lei; Yuan, Hong; Burk, Laurel M.; Inscoe, Christy R.; Hadsell, Michael J.; Chtcheprov, Pavel; Lee, Yueh Z.; Lu, Jianping; Chang, Sha; Zhou, Otto

    2014-03-01

    Microbeam radiation therapy (MRT) is a promising experimental and preclinical radiotherapy method for cancer treatment. Synchrotron based MRT experiments have shown that spatially fractionated microbeam radiation has the unique capability of preferentially eradicating tumour cells while sparing normal tissue in brain tumour bearing animal models. We recently demonstrated the feasibility of generating orthovoltage microbeam radiation with an adjustable microbeam width using a carbon nanotube based x-ray source array. Here we report the preliminary results from our efforts in developing an image guidance procedure for the targeted delivery of the narrow microbeams to the small tumour region in the mouse brain. Magnetic resonance imaging was used for tumour identification, and on-board x-ray radiography was used for imaging of landmarks without contrast agents. The two images were aligned using 2D rigid body image registration to determine the relative position of the tumour with respect to a landmark. The targeting accuracy and consistency were evaluated by first irradiating a group of mice inoculated with U87 human glioma brain tumours using the present protocol and then determining the locations of the microbeam radiation tracks using γ-H2AX immunofluorescence staining. The histology results showed that among 14 mice irradiated, 11 received the prescribed number of microbeams on the targeted tumour, with an average localization accuracy of 454 µm measured directly from the histology (537 µm if measured from the registered histological images). Two mice received one of the three prescribed microbeams on the tumour site. One mouse was excluded from the analysis due to tissue staining errors.

  7. Image-guided microbeam irradiation to brain tumour bearing mice using a carbon nanotube x-ray source array.

    PubMed

    Zhang, Lei; Yuan, Hong; Burk, Laurel M; Inscoe, Christy R; Hadsell, Michael J; Chtcheprov, Pavel; Lee, Yueh Z; Lu, Jianping; Chang, Sha; Zhou, Otto

    2014-03-01

    Microbeam radiation therapy (MRT) is a promising experimental and preclinical radiotherapy method for cancer treatment. Synchrotron based MRT experiments have shown that spatially fractionated microbeam radiation has the unique capability of preferentially eradicating tumour cells while sparing normal tissue in brain tumour bearing animal models. We recently demonstrated the feasibility of generating orthovoltage microbeam radiation with an adjustable microbeam width using a carbon nanotube based x-ray source array. Here we report the preliminary results from our efforts in developing an image guidance procedure for the targeted delivery of the narrow microbeams to the small tumour region in the mouse brain. Magnetic resonance imaging was used for tumour identification, and on-board x-ray radiography was used for imaging of landmarks without contrast agents. The two images were aligned using 2D rigid body image registration to determine the relative position of the tumour with respect to a landmark. The targeting accuracy and consistency were evaluated by first irradiating a group of mice inoculated with U87 human glioma brain tumours using the present protocol and then determining the locations of the microbeam radiation tracks using ?-H2AX immunofluorescence staining. The histology results showed that among 14 mice irradiated, 11 received the prescribed number of microbeams on the targeted tumour, with an average localization accuracy of 454 µm measured directly from the histology (537 µm if measured from the registered histological images). Two mice received one of the three prescribed microbeams on the tumour site. One mouse was excluded from the analysis due to tissue staining errors. PMID:24556798

  8. Shape Classification Using Wasserstein Distance for Brain Morphometry Analysis.

    PubMed

    Su, Zhengyu; Zeng, Wei; Wang, Yalin; Lu, Zhong-Lin; Gu, Xianfeng

    2015-01-01

    Brain morphometry study plays a fundamental role in medical imaging analysis and diagnosis. This work proposes a novel framework for brain cortical surface classification using Wasserstein distance, based on uniformization theory and Riemannian optimal mass transport theory. By Poincare uniformization theorem, all shapes can be conformally deformed to one of the three canonical spaces: the unit sphere, the Euclidean plane or the hyperbolic plane. The uniformization map will distort the surface area elements. The area-distortion factor gives a probability measure on the canonical uniformization space. All the probability measures on a Riemannian manifold form the Wasserstein space. Given any 2 probability measures, there is a unique optimal mass transport map between them, the transportation cost defines the Wasserstein distance between them. Wasserstein distance gives a Riemannian metric for the Wasserstein space. It intrinsically measures the dissimilarities between shapes and thus has the potential for shape classification. To the best of our knowledge, this is the first. work to introduce the optimal mass transport map to general Riemannian manifolds. The method is based on geodesic power Voronoi diagram. Comparing to the conventional methods, our approach solely depends on Riemannian metrics and is invariant under rigid motions and scalings, thus it intrinsically measures shape distance. Experimental results on classifying brain cortical surfaces with different intelligence quotients demonstrated the efficiency and efficacy of our method. PMID:26221691

  9. Shape Classification Using Wasserstein Distance for Brain Morphometry Analysis

    PubMed Central

    Su, Zhengyu; Zeng, Wei; Wang, Yalin; Lu, Zhong-Lin; Gu, Xianfeng

    2015-01-01

    Brain morphometry study plays a fundamental role in medical imaging analysis and diagnosis. This work proposes a novel framework for brain cortical surface classification using Wasserstein distance, based on uniformization theory and Riemannian optimal mass transport theory. By Poincare uniformization theorem, all shapes can be conformally deformed to one of the three canonical spaces: the unit sphere, the Euclidean plane or the hyperbolic plane. The uniformization map will distort the surface area elements. The area-distortion factor gives a probability measure on the canonical uniformization space. All the probability measures on a Riemannian manifold form the Wasserstein space. Given any 2 probability measures, there is a unique optimal mass transport map between them, the transportation cost defines the Wasserstein distance between them. Wasserstein distance gives a Riemannian metric for the Wasserstein space. It intrinsically measures the dissimilarities between shapes and thus has the potential for shape classification. To the best of our knowledge, this is the first work to introduce the optimal mass transport map to general Riemannian manifolds. The method is based on geodesic power Voronoi diagram. Comparing to the conventional methods, our approach solely depends on Riemannian metrics and is invariant under rigid motions and scalings, thus it intrinsically measures shape distance. Experimental results on classifying brain cortical surfaces with different intelligence quotients demonstrated the efficiency and efficacy of our method. PMID:26221691

  10. Multiclass brain-computer interface classification by Riemannian geometry.

    PubMed

    Barachant, Alexandre; Bonnet, Stéphane; Congedo, Marco; Jutten, Christian

    2012-04-01

    This paper presents a new classification framework for brain-computer interface (BCI) based on motor imagery. This framework involves the concept of Riemannian geometry in the manifold of covariance matrices. The main idea is to use spatial covariance matrices as EEG signal descriptors and to rely on Riemannian geometry to directly classify these matrices using the topology of the manifold of symmetric and positive definite (SPD) matrices. This framework allows to extract the spatial information contained in EEG signals without using spatial filtering. Two methods are proposed and compared with a reference method [multiclass Common Spatial Pattern (CSP) and Linear Discriminant Analysis (LDA)] on the multiclass dataset IIa from the BCI Competition IV. The first method, named minimum distance to Riemannian mean (MDRM), is an implementation of the minimum distance to mean (MDM) classification algorithm using Riemannian distance and Riemannian mean. This simple method shows comparable results with the reference method. The second method, named tangent space LDA (TSLDA), maps the covariance matrices onto the Riemannian tangent space where matrices can be vectorized and treated as Euclidean objects. Then, a variable selection procedure is applied in order to decrease dimensionality and a classification by LDA is performed. This latter method outperforms the reference method increasing the mean classification accuracy from 65.1% to 70.2%. PMID:22010143

  11. Long-term supratentorial brain structure and cognitive function following cerebellar tumour resections in childhood.

    PubMed

    Moberget, T; Andersson, S; Lundar, T; Due-Tønnessen, B J; Heldal, A; Endestad, T; Westlye, L T

    2015-03-01

    The cerebellum is connected to extensive regions of the cerebrum, and cognitive deficits following cerebellar lesions may thus be related to disrupted cerebello-cerebral connectivity. Moreover, early cerebellar lesions could affect distal brain development, effectively inducing long-term changes in brain structure and cognitive function. Here, we characterize supratentorial brain structure and cognitive function in 20 adult patients treated for cerebellar tumours in childhood (mean age at surgery: 7.1 years) and 26 matched controls. Relative to controls, patients showed reduced cognitive function and increased grey matter density in bilateral cingulum, left orbitofrontal cortex and the left hippocampus. Within the patient group, increased grey matter density in these regions was associated with decreased performance on tests of processing speed and executive function. Further, diffusion tensor imaging revealed widespread alterations in white matter microstructure in patients. While current ventricle volume (an index of previous hydrocephalus severity it patients) was associated with grey matter density and white matter microstructure in patients, this could only partially account for the observed group differences in brain structure and cognitive function. In conclusion, our results show distal effects of cerebellar lesions on cerebral integrity and wiring, likely caused by a combination of neurodegenerative processes and perturbed neurodevelopment. PMID:25665770

  12. Segmentation, feature extraction, and multiclass brain tumor classification.

    PubMed

    Sachdeva, Jainy; Kumar, Vinod; Gupta, Indra; Khandelwal, Niranjan; Ahuja, Chirag Kamal

    2013-12-01

    Multiclass brain tumor classification is performed by using a diversified dataset of 428 post-contrast T1-weighted MR images from 55 patients. These images are of primary brain tumors namely astrocytoma (AS), glioblastoma multiforme (GBM), childhood tumor-medulloblastoma (MED), meningioma (MEN), secondary tumor-metastatic (MET), and normal regions (NR). Eight hundred fifty-six regions of interest (SROIs) are extracted by a content-based active contour model. Two hundred eighteen intensity and texture features are extracted from these SROIs. In this study, principal component analysis (PCA) is used for reduction of dimensionality of the feature space. These six classes are then classified by artificial neural network (ANN). Hence, this approach is named as PCA-ANN approach. Three sets of experiments have been performed. In the first experiment, classification accuracy by ANN approach is performed. In the second experiment, PCA-ANN approach with random sub-sampling has been used in which the SROIs from the same patient may get repeated during testing. It is observed that the classification accuracy has increased from 77 to 91 %. PCA-ANN has delivered high accuracy for each class: AS-90.74 %, GBM-88.46 %, MED-85 %, MEN-90.70 %, MET-96.67 %, and NR-93.78 %. In the third experiment, to remove bias and to test the robustness of the proposed system, data is partitioned in a manner such that the SROIs from the same patient are not common for training and testing sets. In this case also, the proposed system has performed well by delivering an overall accuracy of 85.23 %. The individual class accuracy for each class is: AS-86.15 %, GBM-65.1 %, MED-63.36 %, MEN-91.5 %, MET-65.21 %, and NR-93.3 %. A computer-aided diagnostic system comprising of developed methods for segmentation, feature extraction, and classification of brain tumors can be beneficial to radiologists for precise localization, diagnosis, and interpretation of brain tumors on MR images. PMID:23645344

  13. Multi-fractal detrended texture feature for brain tumor classification

    NASA Astrophysics Data System (ADS)

    Reza, Syed M. S.; Mays, Randall; Iftekharuddin, Khan M.

    2015-03-01

    We propose a novel non-invasive brain tumor type classification using Multi-fractal Detrended Fluctuation Analysis (MFDFA) [1] in structural magnetic resonance (MR) images. This preliminary work investigates the efficacy of the MFDFA features along with our novel texture feature known as multifractional Brownian motion (mBm) [2] in classifying (grading) brain tumors as High Grade (HG) and Low Grade (LG). Based on prior performance, Random Forest (RF) [3] is employed for tumor grading using two different datasets such as BRATS-2013 [4] and BRATS-2014 [5]. Quantitative scores such as precision, recall, accuracy are obtained using the confusion matrix. On an average 90% precision and 85% recall from the inter-dataset cross-validation confirm the efficacy of the proposed method.

  14. Curcumin inhibits telomerase and induces telomere shortening and apoptosis in brain tumour cells.

    PubMed

    Khaw, Aik Kia; Hande, M Pradeepa; Kalthur, Guruprasad; Hande, M Prakash

    2013-06-01

    Curcumin, a polyphenolic compound isolated from Curcuma longa (Turmeric) is widely used in traditional Ayurvedic medicine. Its potential therapeutic effects on a variety of diseases have long been known. Though anti-tumour effects of curcumin have been reported earlier, its mode of action and telomerase inhibitory effects are not clearly determined in brain tumour cells. In the present study, we demonstrate that curcumin binds to cell surface membrane and infiltrates into cytoplasm to initiate apoptotic events. Curcumin treatment has resulted in higher cytotoxicity in the cells that express telomerase enzyme, highlighting its potential as an anticancer agent. Curcumin induced growth inhibition and cell cycle arrest at G2/M phase in the glioblastoma and medulloblastoma cells used in the study. Gene and protein expression analyses revealed that curcumin down-regulated CCNE1, E2F1 and CDK2 and up-regulated the expression of PTEN genes resulting in growth arrest at G2/M phase. Curcumin-induced apoptosis is found to be associated with increased caspase-3/7 activity and overexpression of Bax. In addition, down-regulation of Bcl2 and survivin was observed in curcumin-treated cells. Besides these effects, we found curcumin to be inhibiting telomerase activity and down-regulating hTERT mRNA expression leading to telomere shortening. We conclude that telomerase inhibitory effects of curcumin underscore its use in adjuvant cancer therapy. PMID:23192708

  15. Identification and Classification of Hubs in Brain Networks

    PubMed Central

    Sporns, Olaf; Honey, Christopher J.; Kötter, Rolf

    2007-01-01

    Brain regions in the mammalian cerebral cortex are linked by a complex network of fiber bundles. These inter-regional networks have previously been analyzed in terms of their node degree, structural motif, path length and clustering coefficient distributions. In this paper we focus on the identification and classification of hub regions, which are thought to play pivotal roles in the coordination of information flow. We identify hubs and characterize their network contributions by examining motif fingerprints and centrality indices for all regions within the cerebral cortices of both the cat and the macaque. Motif fingerprints capture the statistics of local connection patterns, while measures of centrality identify regions that lie on many of the shortest paths between parts of the network. Within both cat and macaque networks, we find that a combination of degree, motif participation, betweenness centrality and closeness centrality allows for reliable identification of hub regions, many of which have previously been functionally classified as polysensory or multimodal. We then classify hubs as either provincial (intra-cluster) hubs or connector (inter-cluster) hubs, and proceed to show that lesioning hubs of each type from the network produces opposite effects on the small-world index. Our study presents an approach to the identification and classification of putative hub regions in brain networks on the basis of multiple network attributes and charts potential links between the structural embedding of such regions and their functional roles. PMID:17940613

  16. Leukaemia, brain tumours and exposure to extremely low frequency magnetic fields: cohort study of Swiss railway employees

    PubMed Central

    Röösli, Martin; Lörtscher, Manfred; Egger, Matthias; Pfluger, Dominik; Schreier, Nadja; Lörtscher, Emanuel; Locher, Peter; Spoerri, Adrian; Minder, Christoph

    2007-01-01

    Aims To investigate the relationship between extremely low frequency magnetic field (ELF?MF) exposure and mortality from leukaemia and brain tumour in a cohort of Swiss railway workers. Methods 20?141 Swiss railway employees with 464?129 person?years of follow?up between 1972 and 2002 were studied. Mortality rates for leukaemia and brain tumour of highly exposed train drivers (21??T average annual exposure) were compared with medium and low exposed occupational groups (i.e. station masters with an average exposure of 1??T). In addition, individual cumulative exposure was calculated from on?site measurements and modelling of past exposures. Results The hazard ratio (HR) for leukaemia mortality of train drivers was 1.43 (95% CI 0.74 to 2.77) compared with station masters. For myeloid leukaemia the HR of train drivers was 4.74 (95% CI 1.04 to 21.60) and for Hodgkin's disease 3.29 (95% CI 0.69 to 15.63). Lymphoid leukaemia, non?Hodgkin's disease and brain tumour mortality were not associated with magnetic field exposure. Concordant results were obtained from analyses based on individual cumulative exposure. Conclusions Some evidence of an exposure–response association was found for myeloid leukaemia and Hodgkin's disease, but not for other haematopoietic and lymphatic malignancies and brain tumours. PMID:17525094

  17. A structural and functional magnetic resonance imaging dataset of brain tumour patients

    PubMed Central

    Pernet, Cyril R.; Gorgolewski, Krzysztof J.; Job, Dominic; Rodriguez, David; Whittle, Ian; Wardlaw, Joanna

    2016-01-01

    We collected high resolution structural (T1, T2, DWI) and several functional (BOLD T2*) MRI data in 22 patients with different types of brain tumours. Functional imaging protocols included a motor task, a verb generation task, a word repetition task and resting state. Imaging data are complemented by demographics (age, sex, handedness, and pathology), behavioural results to motor and cognitive tests and direct cortical electrical stimulation data (pictures of stimulation sites with outcomes) performed during surgery. Altogether, these data are suited to test functional imaging methods for single subject analyses, in particular methods that focus on locating eloquent cortical areas, critical functional and/or structural network hubs, and predict patient status based on imaging data (presurgical mapping). PMID:26836205

  18. A structural and functional magnetic resonance imaging dataset of brain tumour patients.

    PubMed

    Pernet, Cyril R; Gorgolewski, Krzysztof J; Job, Dominic; Rodriguez, David; Whittle, Ian; Wardlaw, Joanna

    2016-01-01

    We collected high resolution structural (T1, T2, DWI) and several functional (BOLD T2*) MRI data in 22 patients with different types of brain tumours. Functional imaging protocols included a motor task, a verb generation task, a word repetition task and resting state. Imaging data are complemented by demographics (age, sex, handedness, and pathology), behavioural results to motor and cognitive tests and direct cortical electrical stimulation data (pictures of stimulation sites with outcomes) performed during surgery. Altogether, these data are suited to test functional imaging methods for single subject analyses, in particular methods that focus on locating eloquent cortical areas, critical functional and/or structural network hubs, and predict patient status based on imaging data (presurgical mapping). PMID:26836205

  19. OPTIMIZING BRAIN CONNECTIVITY NETWORKS FOR DISEASE CLASSIFICATION USING EPIC

    PubMed Central

    Prasad, Gautam; Joshi, Shantanu H.; Thompson, Paul M.

    2014-01-01

    We propose a method to adaptively select an optimal cortical segmentation for brain connectivity analysis that maximizes feature-based disease classification performance. In standard structural connectivity analysis, the cortex is typically subdivided (parcellated) into N anatomical regions. White matter fiber pathways from tractography are used to compute an N × N matrix, which represents the pairwise connectivity between those regions. We optimize this representation by sampling over the space of possible region combinations and represent each configuration as a set partition of the N anatomical regions. Each partition is assigned a score using accuracy from a support vector machine (SVM) classifier of connectivity matrices in a group of patients and controls. We then define a high-dimensional optimization problem using simulated annealing to identify an optimal partition for maximum classification accuracy. We evaluate the results separately on test data using cross-validation. Specifically, we demonstrate results on the ADNI-2 dataset, where we optimally parcellate the cortex to yield an 85% classification accuracy using connectivity information alone. We refer to our method as evolving partitions to improve connectomics (EPIC). PMID:25405000

  20. Analysis of tumour- and stroma-supplied proteolytic networks reveals a brain-metastasis-promoting role for cathepsin S.

    PubMed

    Sevenich, Lisa; Bowman, Robert L; Mason, Steven D; Quail, Daniela F; Rapaport, Franck; Elie, Benelita T; Brogi, Edi; Brastianos, Priscilla K; Hahn, William C; Holsinger, Leslie J; Massagué, Joan; Leslie, Christina S; Joyce, Johanna A

    2014-09-01

    Metastasis remains the most common cause of death in most cancers, with limited therapies for combating disseminated disease. While the primary tumour microenvironment is an important regulator of cancer progression, it is less well understood how different tissue environments influence metastasis. We analysed tumour-stroma interactions that modulate organ tropism of brain, bone and lung metastasis in xenograft models. We identified a number of potential modulators of site-specific metastasis, including cathepsin S as a regulator of breast-to-brain metastasis. High cathepsin S expression at the primary site correlated with decreased brain metastasis-free survival in breast cancer patients. Both macrophages and tumour cells produce cathepsin S, and only the combined depletion significantly reduced brain metastasis in vivo. Cathepsin S specifically mediates blood-brain barrier transmigration through proteolytic processing of the junctional adhesion molecule, JAM-B. Pharmacological inhibition of cathepsin S significantly reduced experimental brain metastasis, supporting its consideration as a therapeutic target for this disease. PMID:25086747

  1. Radioisotope scanning of brain, liver, lung and bone with a note on tumour localizing agents

    PubMed Central

    Lavender, J. P.

    1973-01-01

    Radioisotopic scanning of brain, liver, lungs and the skeleton is briefly reviewed with a survey of recent developments of clinical significance. In brain scanning neoplasm detection rates of greater than 90% are claimed. The true figure is probably 70-80%. Autopsy data shows a number of false negatives, particularly with vascular lesions. Attempts to make scanning more specific in differentiating neoplasm from vascular lesions by rapid sequence blood flow studies are reviewed. In liver scanning by means of colloids again high success rate is claimed but small metastases are frequently missed and the false negative scan rate is probably quite high. Lung scanning still has its main place in investigating pulmonary embolic disease. Ventilation studies using Xenon 133 are useful, particularly combined with perfusion studies. The various radiopharmaceuticals for use in bone scanning are reviewed. The appearance of technetium labelled phosphate compounds will probably allow much wider use of total skeletal scanning. Research into tumour localizing agents continues, the most recent and interesting being Gallium citrate and labelled bleomycin. Neither agent is predictable however although Gallium may have a place in Hodgkins disease and bronchogenic neoplasm and both may have a place in the detection of cerebral tumours. ImagesFig. 1Fig. 2Fig. 3p452-bFig. 3bFig. 4Fig. 5Fig. 5bFig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11Fig. 12Fig. 12c & 12dFig. 13Fig. 13 b,c,dFig. 14Fig. 14bFig. 15Fig. 15bFig. 16Fig. 17Fig. 18 PMID:4602127

  2. Classification of Types of Stuttering Symptoms Based on Brain Activity

    PubMed Central

    Jiang, Jing; Lu, Chunming; Peng, Danling; Zhu, Chaozhe; Howell, Peter

    2012-01-01

    Among the non-fluencies seen in speech, some are more typical (MT) of stuttering speakers, whereas others are less typical (LT) and are common to both stuttering and fluent speakers. No neuroimaging work has evaluated the neural basis for grouping these symptom types. Another long-debated issue is which type (LT, MT) whole-word repetitions (WWR) should be placed in. In this study, a sentence completion task was performed by twenty stuttering patients who were scanned using an event-related design. This task elicited stuttering in these patients. Each stuttered trial from each patient was sorted into the MT or LT types with WWR put aside. Pattern classification was employed to train a patient-specific single trial model to automatically classify each trial as MT or LT using the corresponding fMRI data. This model was then validated by using test data that were independent of the training data. In a subsequent analysis, the classification model, just established, was used to determine which type the WWR should be placed in. The results showed that the LT and the MT could be separated with high accuracy based on their brain activity. The brain regions that made most contribution to the separation of the types were: the left inferior frontal cortex and bilateral precuneus, both of which showed higher activity in the MT than in the LT; and the left putamen and right cerebellum which showed the opposite activity pattern. The results also showed that the brain activity for WWR was more similar to that of the LT and fluent speech than to that of the MT. These findings provide a neurological basis for separating the MT and the LT types, and support the widely-used MT/LT symptom grouping scheme. In addition, WWR play a similar role as the LT, and thus should be placed in the LT type. PMID:22761887

  3. Retrieving Binary Answers Using Whole-Brain Activity Pattern Classification

    PubMed Central

    Nawa, Norberto E.; Ando, Hiroshi

    2015-01-01

    Multivariate pattern analysis (MVPA) has been successfully employed to advance our understanding of where and how information regarding different mental states is represented in the human brain, bringing new insights into how these states come to fruition, and providing a promising complement to the mass-univariate approach. Here, we employed MVPA to classify whole-brain activity patterns occurring in single fMRI scans, in order to retrieve binary answers from experiment participants. Five healthy volunteers performed two types of mental task while in the MRI scanner: counting down numbers and recalling positive autobiographical events. Data from these runs were used to train individual machine learning based classifiers that predicted which mental task was being performed based on the voxel-based brain activity patterns. On a different day, the same volunteers reentered the scanner and listened to six statements (e.g., “the month you were born is an odd number”), and were told to countdown numbers if the statement was true (yes) or recall positive events otherwise (no). The previously trained classifiers were then used to assign labels (yes/no) to the scans collected during the 24-second response periods following each one of the statements. Mean classification accuracies at the single scan level were in the range of 73.6 to 80.8%, significantly above chance for all participants. When applying a majority vote on the scans within each response period, i.e., the most frequent label (yes/no) in the response period becomes the answer to the previous statement, 5.0 to 5.8 sentences, out of 6, were correctly classified in each one of the runs, on average. These results indicate that binary answers can be retrieved from whole-brain activity patterns, suggesting that MVPA provides an alternative way to establish basic communication with unresponsive patients when other techniques are not successful. PMID:26778992

  4. Increasing Rates of Brain Tumours in the Swedish National Inpatient Register and the Causes of Death Register

    PubMed Central

    Hardell, Lennart; Carlberg, Michael

    2015-01-01

    Radiofrequency emissions in the frequency range 30 kHz–300 GHz were evaluated to be Group 2B, i.e., “possibly”, carcinogenic to humans by the International Agency for Research on Cancer (IARC) at WHO in May 2011. The Swedish Cancer Register has not shown increasing incidence of brain tumours in recent years and has been used to dismiss epidemiological evidence on a risk. In this study we used the Swedish National Inpatient Register (IPR) and Causes of Death Register (CDR) to further study the incidence comparing with the Cancer Register data for the time period 1998–2013 using joinpoint regression analysis. In the IPR we found a joinpoint in 2007 with Annual Percentage Change (APC) +4.25%, 95% CI +1.98, +6.57% during 2007–2013 for tumours of unknown type in the brain or CNS. In the CDR joinpoint regression found one joinpoint in 2008 with APC during 2008–2013 +22.60%, 95% CI +9.68, +37.03%. These tumour diagnoses would be based on clinical examination, mainly CT and/or MRI, but without histopathology or cytology. No statistically significant increasing incidence was found in the Swedish Cancer Register during these years. We postulate that a large part of brain tumours of unknown type are never reported to the Cancer Register. Furthermore, the frequency of diagnosis based on autopsy has declined substantially due to a general decline of autopsies in Sweden adding further to missing cases. We conclude that the Swedish Cancer Register is not reliable to be used to dismiss results in epidemiological studies on the use of wireless phones and brain tumour risk. PMID:25854296

  5. Brain tissue segmentation in 4D CT using voxel classification

    NASA Astrophysics Data System (ADS)

    van den Boom, R.; Oei, M. T. H.; Lafebre, S.; Oostveen, L. J.; Meijer, F. J. A.; Steens, S. C. A.; Prokop, M.; van Ginneken, B.; Manniesing, R.

    2012-02-01

    A method is proposed to segment anatomical regions of the brain from 4D computer tomography (CT) patient data. The method consists of a three step voxel classification scheme, each step focusing on structures that are increasingly difficult to segment. The first step classifies air and bone, the second step classifies vessels and the third step classifies white matter, gray matter and cerebrospinal fluid. As features the time averaged intensity value and the temporal intensity change value were used. In each step, a k-Nearest-Neighbor classifier was used to classify the voxels. Training data was obtained by placing regions of interest in reconstructed 3D image data. The method has been applied to ten 4D CT cerebral patient data. A leave-one-out experiment showed consistent and accurate segmentation results.

  6. 77 FR 16925 - Medical Devices; Neurological Devices; Classification of the Near Infrared Brain Hematoma Detector

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-23

    ...; Classification of the Near Infrared Brain Hematoma Detector AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. SUMMARY: The Food and Drug Administration (FDA) is classifying the Near Infrared (NIR) Brain... generic name Near Infrared (NIR) Brain Hematoma Detector, and it is identified as a noninvasive...

  7. Occupational exposure to magnetic fields and brain tumours in central Sweden.

    PubMed

    Rodvall, Y; Ahlbom, A; Stenlund, C; Preston-Martin, S; Lindh, T; Spännare, B

    1998-09-01

    Occupations with exposure to magnetic fields were studied in a population-based case-control study of male glioma and meningioma in Central Sweden. The study included 84 cases of glioma, 20 cases of meningioma and 155 controls. Information about job titles was obtained by means of a questionnaire. Three different methods were used to classify exposure 1) 'electrical occupations', 2) assessment of magnetic fields by an electrical engineer, 3) job values based on magnetic field measurements at work sites for occupational groups. When analyses were based on 'electrical occupations' a relative risk (RR) of 1.0 (95% CI: 0.4-2.4) was seen for glioma and 1.8 (95% CI: 0.3-3.6) for meningioma. When analyses were based on measurements a relative risk of 1.9 (95% CI: 0.8-5.0) was seen for glioma and 1.6 (95% CI: 0.3-10.2) for those ever in an exposed job of an average mean value of > 0.4 microT. A larger number of individuals was classified as exposed, when exposure was based on measurements. Information was available regarding several potential confounders, but none of them seemed to be of any importance. Our conclusion is that the results based on magnetic field measurements give some support to the hypothesis that magnetic fields exposure may play a role in the development of brain tumours. PMID:9794123

  8. Multiple instance learning for classification of dementia in brain MRI.

    PubMed

    Tong, Tong; Wolz, Robin; Gao, Qinquan; Guerrero, Ricardo; Hajnal, Joseph V; Rueckert, Daniel

    2014-07-01

    Machine learning techniques have been widely used to detect morphological abnormalities from structural brain magnetic resonance imaging data and to support the diagnosis of neurological diseases such as dementia. In this paper, we propose to use a multiple instance learning (MIL) method in an application for the detection of Alzheimer's disease (AD) and its prodromal stage mild cognitive impairment (MCI). In our work, local intensity patches are extracted as features. However, not all the patches extracted from patients with dementia are equally affected by the disease and some of them may not be characteristic of morphology associated with the disease. Therefore, there is some ambiguity in assigning disease labels to these patches. The problem of the ambiguous training labels can be addressed by weakly supervised learning techniques such as MIL. A graph is built for each image to exploit the relationships among the patches and then to solve the MIL problem. The constructed graphs contain information about the appearances of patches and the relationships among them, which can reflect the inherent structures of images and aids the classification. Using the baseline MR images of 834 subjects from the ADNI study, the proposed method can achieve a classification accuracy of 89% between AD patients and healthy controls, and 70% between patients defined as stable MCI and progressive MCI in a leave-one-out cross validation. Compared with two state-of-the-art methods using the same dataset, the proposed method can achieve similar or improved results, providing an alternative framework for the detection and prediction of neurodegenerative diseases. PMID:24858570

  9. Double-labelling immunohistochemistry for MGMT and a “cocktail” of non-tumourous elements is a reliable, quick and easy technique for inferring methylation status in glioblastomas and other primary brain tumours

    PubMed Central

    2013-01-01

    Background Our aim was to develop a new protocol for MGMT immunohistochemistry with good agreement between observers and good correlation with molecular genetic tests of tumour methylation. We examined 40 primary brain tumours (30 glioblastomas and 10 oligodendroglial tumours) with our new technique, namely double-labelling immunohistochemistry for MGMT and a "cocktail" of non-tumour antigens (CD34, CD45 and CD68). We compared the results with single-labelling immunohistochemistry for MGMT and methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA, a recognised molecular genetic technique which we applied as the gold-standard for the methylation status). Results Double-labelling immunohistochemistry for MGMT produced a visual separation of tumourous and non-tumourous elements on the same histological slide, making it quick and easy to determine whether tumour cell nuclei were MGMT-positive or MGMT-negative (and thereby infer the methylation status of the tumour). We found good agreement between observers (kappa 0.76) and within observer (kappa 0.84). Furthermore, double-labelling showed good specificity (80%), sensitivity (73.33%), positive predictive value (PPV, 83.33%) and negative predictive value (NPV, 68.75%) compared to MS-MLPA. Double-labelling was quicker and easier to assess than single-labelling and it outperformed quantitative computerised image analysis of MGMT single-labelling in terms of sensitivity, specificity, PPV and NPV. Conclusions Double-labelling immunohistochemistry for MGMT and a cocktail of non-tumourous elements provides a "one look" method for determining whether tumour cell nuclei are MGMT-positive or MGMT-negative. This can be used to infer the methylation status of the tumour. There is good observer agreement and good specificity, sensitivity, PPV and NPV compared to a molecular gold-standard. PMID:24252243

  10. Brain tumour imaging with carbon-11 choline: comparison with FDG PET and gadolinium-enhanced MR imaging.

    PubMed

    Ohtani, T; Kurihara, H; Ishiuchi, S; Saito, N; Oriuchi, N; Inoue, T; Sasaki, T

    2001-11-01

    The purpose of this study was to assess the clinical potential of methyl-11C-choline (11C-choline) in the diagnosis of brain tumours. To this end, the results of 11C-choline positron emission tomography (PET) in 22 patients suspected of having brain tumours were compared with the findings of contrast-enhanced magnetic resonance (MR) imaging and fluorine-18 fluorodeoxyglucose PET. A histopathological diagnosis was made for each patient during open surgery. The standardised uptake values of brain tumours and the tumour-to-white matter count (T/W) ratios were determined. The degree of 11C-choline accumulation noted in PET images was compared with the gadolinium-enhanced areas of MR images. The mean T/W ratio of 11C-choline in high-grade gliomas was found to be higher than that in low-grade gliomas. This difference was statistically significant (mean+/-SD: 8.7+/-6.2, n=9 versus 1.5+/-0.7, n=5, P<0.03) when data pertaining to the prominent uptake of 11C-choline in a patient with a pilocytic astrocytoma were excluded. 11C-choline PET failed to detect non-neoplastic lesions in two patients. Areas of 11C-choline accumulation in PET scans were larger than areas enhanced on MR images in five cases involving high-grade gliomas. 11C-choline PET differentiated between low-grade gliomas and high-grade gliomas, but did not differentiate between low-grade gliomas and non-neoplastic lesions. The combination of 11C-choline PET and MR imaging may provide investigators with an accurate means by which to identify high-grade gliomas. PMID:11702108

  11. Constrained customization of non-coplanar beam orientations in radiotherapy of brain tumours.

    PubMed

    Rowbottom, C G; Oldham, M; Webb, S

    1999-02-01

    A methodology for the constrained customization of non-coplanar beam orientations in radiotherapy treatment planning has been developed and tested on a cohort of five patients with tumours of the brain. The methodology employed a combination of single and multibeam cost functions to produce customized beam orientations. The single-beam cost function was used to reduce the search space for the multibeam cost function, which was minimized using a fast simulated annealing algorithm. The scheme aims to produce well-spaced, customized beam orientations for each patient that produce low dose to organs at risk (OARs). The customized plans were compared with standard plans containing the number and orientation of beams chosen by a human planner. The beam orientation constraint-customized plans employed the same number of treatment beams as the standard plan but with beam orientations chosen by the constrained-customization scheme. Improvements from beam orientation constraint-customization were studied in isolation by customizing the beam weights of both plans using a dose-based downhill simplex algorithm. The results show that beam orientation constraint-customization reduced the maximum dose to the orbits by an average of 18.8 (+/-3.8, ISD)% and to the optic nerves by 11.4 (+/-4.8, ISD)% with no degradation of the planning target volume (PTV) dose distribution. The mean doses, averaged over the patient cohort, were reduced by 4.2 (+/-1.1, ISD)% and 12.4 (+/-3.1, ISD)% for the orbits and optic nerves respectively. In conclusion, the beam orientation constraint-customization can reduce the dose to OARs, for few-beam treatment plans, when compared with standard treatment plans developed by a human planner. PMID:10070789

  12. A standardized and reproducible protocol for serum-free monolayer culturing of primary paediatric brain tumours to be utilized for therapeutic assays

    PubMed Central

    Sandén, Emma; Eberstål, Sofia; Visse, Edward; Siesjö, Peter; Darabi, Anna

    2015-01-01

    In vitro cultured brain tumour cells are indispensable tools for drug screening and therapeutic development. Serum-free culture conditions tentatively preserve the features of the original tumour, but commonly comprise neurosphere propagation, which is a technically challenging procedure. Here, we define a simple, non-expensive and reproducible serum-free cell culture protocol for establishment and propagation of primary paediatric brain tumour cultures as adherent monolayers. The success rates for establishment of primary cultures (including medulloblastomas, atypical rhabdoid tumour, ependymomas and astrocytomas) were 65% (11/17) and 78% (14/18) for sphere cultures and monolayers respectively. Monolayer culturing was particularly feasible for less aggressive tumour subsets, where neurosphere cultures could not be generated. We show by immunofluorescent labelling that monolayers display phenotypic similarities with corresponding sphere cultures and primary tumours, and secrete clinically relevant inflammatory factors, including PGE2, VEGF, IL-6, IL-8 and IL-15. Moreover, secretion of PGE2 was considerably reduced by treatment with the COX-2 inhibitor Valdecoxib, demonstrating the functional utility of our newly established monolayer for preclinical therapeutic assays. Our findings suggest that this culture method could increase the availability and comparability of clinically representative in vitro models of paediatric brain tumours, and encourages further molecular evaluation of serum-free monolayer cultures. PMID:26183281

  13. Pharmaco-thermodynamics of deuterium-induced oedema in living rat brain via 1H2O MRI: implications for boron neutron capture therapy of malignant brain tumours

    NASA Astrophysics Data System (ADS)

    Medina, Daniel C.; Li, Xin; Springer, Charles S., Jr.

    2005-05-01

    In addition to its common usage as a tracer in metabolic and physiological studies, deuterium possesses anti-tumoural activity and confers protection against ?-irradiation. A more recent interest in deuterium emanates from the search for alternatives capable of improving neutron penetrance whilst reducing healthy tissue radiation dose deposition in boron neutron capture therapy of malignant brain tumours. Despite this potential clinical application, deuterium induces brain oedema, which is detrimental to neutron capture therapy. In this study, five adult male rats were titrated with deuterated drinking water while brain oedema was monitored via water proton magnetic resonance imaging. This report concludes that deuterium, as well as deuterium-induced brain oedema, possesses a uniform brain bio-distribution. At a steady-state blood fluid deuteration value of 16%, when the deuterium isotope fraction in drinking water was 25%, a mean oedematous volume change of 9 ± 2% (p-value <0.001) was observed in the rat brain—this may account for neurological and behavioural abnormalities found in mammals drinking highly deuterated water. In addition to characterizing the pharmaco-thermodynamics of deuterium-induced oedema, this report also estimates the impact of oedema on thermal neutron enhancement and effective dose reduction factors using simple linear transport calculations. While body fluid deuteration enhances thermal neutron flux penetrance and reduces dose deposition, oedema has the opposite effect because it increases the volume of interest, e.g., the brain volume. Thermal neutron enhancement and effective dose reduction factors could be reduced by as much as ~10% in the presence of a 9% water volume increase (oedema). All three authors have contributed equally to this work.

  14. Penetration and intracellular uptake of poly(glycerol-adipate) nanoparticles into three-dimensional brain tumour cell culture models.

    PubMed

    Meng, Weina; Garnett, Martin C; Walker, David A; Parker, Terence L

    2016-03-01

    Nanoparticle (NP) drug delivery systems may potentially enhance the efficacy of therapeutic agents. It is difficult to characterize many important properties of NPs in vivo and therefore attempts have been made to use realistic in vitro multicellular spheroids instead. In this paper, we have evaluated poly(glycerol-adipate) (PGA) NPs as a potential drug carrier for local brain cancer therapy. Various three-dimensional (3-D) cell culture models have been used to investigate the delivery properties of PGA NPs. Tumour cells in 3-D culture showed a much higher level of endocytic uptake of NPs than a mixed normal neonatal brain cell population. Differences in endocytic uptake of NPs in 2-D and 3-D models strongly suggest that it is very important to use in vitro 3-D cell culture models for evaluating this parameter. Tumour penetration of NPs is another important parameter which could be studied in 3-D cell models. The penetration of PGA NPs through 3-D cell culture varied between models, which will therefore require further study to develop useful and realistic in vitro models. Further use of 3-D cell culture models will be of benefit in the future development of new drug delivery systems, particularly for brain cancers which are more difficult to study in vivo. PMID:26568330

  15. Paediatric head CT scan and subsequent risk of malignancy and benign brain tumour: a nation-wide population-based cohort study

    PubMed Central

    Huang, W-Y; Muo, C-H; Lin, C-Y; Jen, Y-M; Yang, M-H; Lin, J-C; Sung, F-C; Kao, C-H

    2014-01-01

    Background: To evaluate the possible association between paediatric head computed tomography (CT) examination and increased subsequent risk of malignancy and benign brain tumour. Methods: In the exposed cohort, 24?418 participants under 18 years of age, who underwent head CT examination between 1998 and 2006, were identified from the Taiwan National Health Insurance Research Database (NHIRD). Patients were followed up until a diagnosis of malignant disease or benign brain tumour, withdrawal from the National Health Insurance (NHI) system, or at the end of 2008. Results: The overall risk was not significantly different in the two cohorts (incidence rate=36.72 per 100?000 person-years in the exposed cohort, 28.48 per 100?000 person-years in the unexposed cohort, hazard ratio (HR)=1.29, 95% confidence interval (CI)=0.90–1.85). The risk of benign brain tumour was significantly higher in the exposed cohort than in the unexposed cohort (HR=2.97, 95% CI=1.49–5.93). The frequency of CT examination showed strong correlation with the subsequent overall risk of malignancy and benign brain tumour. Conclusions: We found that paediatric head CT examination was associated with an increased incidence of benign brain tumour. A large-scale study with longer follow-up is necessary to confirm this result. PMID:24569470

  16. A multinational case-control study on childhood brain tumours, anthropogenic factors, birth characteristics and prenatal exposures: A validation of interview data.

    PubMed

    Vienneau, Danielle; Infanger, Denis; Feychting, Maria; Schüz, Joachim; Schmidt, Lisbeth Samsø; Poulsen, Aslak Harbo; Tettamanti, Giorgio; Klæboe, Lars; Kuehni, Claudia E; Tynes, Tore; Von der Weid, Nicolas; Lannering, Birgitta; Röösli, Martin

    2016-02-01

    Little is known about the aetiology of childhood brain tumours. We investigated anthropometric factors (birth weight, length, maternal age), birth characteristics (e.g. vacuum extraction, preterm delivery, birth order) and exposures during pregnancy (e.g. maternal: smoking, working, dietary supplement intake) in relation to risk of brain tumour diagnosis among 7-19 year olds. The multinational case-control study in Denmark, Sweden, Norway and Switzerland (CEFALO) included interviews with 352 (participation rate=83.2%) eligible cases and 646 (71.1%) population-based controls. Interview data were complemented with data from birth registries and validated by assessing agreement (Cohen's Kappa). We used conditional logistic regression models matched on age, sex and geographical region (adjusted for maternal age and parental education) to explore associations between birth factors and childhood brain tumour risk. Agreement between interview and birth registry data ranged from moderate (Kappa=0.54; worked during pregnancy) to almost perfect (Kappa=0.98; birth weight). Neither anthropogenic factors nor birth characteristics were associated with childhood brain tumour risk. Maternal vitamin intake during pregnancy was indicative of a protective effect (OR 0.75, 95%-CI: 0.56-1.01). No association was seen for maternal smoking during pregnancy or working during pregnancy. We found little evidence that the considered birth factors were related to brain tumour risk among children and adolescents. PMID:26625087

  17. Assessing Occupational Exposure to Chemicals in an International Epidemiological Study of Brain Tumours

    PubMed Central

    van Tongeren, Martie

    2013-01-01

    The INTEROCC project is a multi-centre case–control study investigating the risk of developing brain cancer due to occupational chemical and electromagnetic field exposures. To estimate chemical exposures, the Finnish Job Exposure Matrix (FINJEM) was modified to improve its performance in the INTEROCC study and to address some of its limitations, resulting in the development of the INTEROCC JEM. An international team of occupational hygienists developed a crosswalk between the Finnish occupational codes used in FINJEM and the International Standard Classification of Occupations 1968 (ISCO68). For ISCO68 codes linked to multiple Finnish codes, weighted means of the exposure estimates were calculated. Similarly, multiple ISCO68 codes linked to a single Finnish code with evidence of heterogeneous exposure were refined. One of the key time periods in FINJEM (1960–1984) was split into two periods (1960–1974 and 1975–1984). Benzene exposure estimates in early periods were modified upwards. The internal consistency of hydrocarbon exposures and exposures to engine exhaust fumes was improved. Finally, exposure to polycyclic aromatic hydrocarbon and benzo(a)pyrene was modified to include the contribution from second-hand smoke. The crosswalk ensured that the FINJEM exposure estimates could be applied to the INTEROCC study subjects. The modifications generally resulted in an increased prevalence of exposure to chemical agents. This increased prevalence of exposure was not restricted to the lowest categories of cumulative exposure, but was seen across all levels for some agents. Although this work has produced a JEM with important improvements compared to FINJEM, further improvements are possible with the expansion of agents and additional external data. PMID:23467593

  18. Epidemiology of glial and non-glial brain tumours in Europe.

    PubMed

    Crocetti, Emanuele; Trama, Annalisa; Stiller, Charles; Caldarella, Adele; Soffietti, Riccardo; Jaal, Jana; Weber, Damien C; Ricardi, Umberto; Slowinski, Jerzy; Brandes, Alba

    2012-07-01

    To the central nervous system (CNS) belong a heterogeneous group of glial and non glial rare cancers. The aim of the present study was to estimate the burden (incidence, prevalence, survival and proportion of cured) for the principal CNS cancers in Europe (EU27) and in European regions using population-based data from cancer registries participating in the RARECARE project. We analysed 44,947 rare CNS cancers diagnosed from 1995 to 2002 (with follow up at 31st December 2003): 86.0% astrocytic (24% low grade, 63% high grade and 13% glioma NOS), 6.4% oligodendroglial (74% low grade), 3.6% ependymal (85% low grade), 4.1% Embryonal tumours and 0.1% choroid plexus carcinoma. Incidence rates vary widely across European regions especially for astrocytic tumours ranging from 3/100,000 in Eastern Europe to 5/100,000 in United Kingdom and Ireland. Overall, about 27,700 new rare CNS cancers were estimated every year in EU27, for an annual incidence rate of 4.8 per 100,000 for astrocytic, 0.4 for oligodendroglial, 0.2 for ependymal and embryonal tumours and less than 0.1 for choroid plexus carcinoma. More than 154,000 persons with rare CNS were estimated alive (prevalent cases) in the EU at the beginning of 2008. Five-year relative survival was 14.5% for astrocytic tumours (42.6% for low grade, 4.9% for high grade and 17.5% for glioma NOS), 54.5% for oligodendroglial (64.9% high grade and 29.6% low grade), 74.2% for ependymal (80.4% low grade and 36.6% high grade), 62.8% for choroid plexus carcinomas and 56.8% for embryonal tumours. Survival rates for astrocytic tumours were relatively higher in Northern and Central Europe than in Eastern Europe and in UK and Ireland. The different availability of diagnostic imaging techniques and/or radiation therapy equipment across Europe may contribute to explain the reported survival differences. The estimated proportion of cured patients was 7.9% for the 'glial' group to which belong astrocytic tumours. Overall results are strongly influenced by astrocytic tumours that are the most common type. This is the first study to delineate the rare CNS cancer burden in Europe by age, sex and European region. PMID:22227039

  19. Mir-34a Mimics Are Potential Therapeutic Agents for p53-Mutated and Chemo-Resistant Brain Tumour Cells

    PubMed Central

    Fan, Yuen Ngan; Meley, Daniel; Pizer, Barry; Sée, Violaine

    2014-01-01

    Chemotherapeutic drug resistance and relapse remains a major challenge for paediatric (medulloblastoma) and adult (glioblastoma) brain tumour treatment. Medulloblastoma tumours and cell lines with mutations in the p53 signalling pathway have been shown to be specifically insensitive to DNA damaging agents. The aim of this study was to investigate the potential of triggering cell death in p53 mutated medulloblastoma cells by a direct activation of pro-death signalling downstream of p53 activation. Since non-coding microRNAs (miRNAs) have the ability to fine tune the expression of a variety of target genes, orchestrating multiple downstream effects, we hypothesised that triggering the expression of a p53 target miRNA could induce cell death in chemo-resistant cells. Treatment with etoposide, increased miR-34a levels in a p53-dependent fashion and the level of miR-34a transcription was correlated with the cell sensitivity to etoposide. miR-34a activity was validated by measuring the expression levels of one of its well described target: the NADH dependent sirtuin1 (SIRT1). Whilst drugs directly targeting SIRT1, were potent to trigger cell death at high concentrations only, introduction of synthetic miR-34a mimics was able to induce cell death in p53 mutated medulloblastoma and glioblastoma cell lines. Our results show that the need of a functional p53 signaling pathway can be bypassed by direct activation of miR-34a in brain tumour cells. PMID:25250818

  20. Boosting brain connectome classification accuracy in Alzheimer's disease using higher-order singular value decomposition

    PubMed Central

    Zhan, Liang; Liu, Yashu; Wang, Yalin; Zhou, Jiayu; Jahanshad, Neda; Ye, Jieping; Thompson, Paul M.

    2015-01-01

    Alzheimer's disease (AD) is a progressive brain disease. Accurate detection of AD and its prodromal stage, mild cognitive impairment (MCI), are crucial. There is also a growing interest in identifying brain imaging biomarkers that help to automatically differentiate stages of Alzheimer's disease. Here, we focused on brain structural networks computed from diffusion MRI and proposed a new feature extraction and classification framework based on higher order singular value decomposition and sparse logistic regression. In tests on publicly available data from the Alzheimer's Disease Neuroimaging Initiative, our proposed framework showed promise in detecting brain network differences that help in classifying different stages of Alzheimer's disease. PMID:26257601

  1. Increased levels of type VIII collagen in human brain tumours compared to normal brain tissue and non-neoplastic cerebral disorders.

    PubMed Central

    Paulus, W.; Sage, E. H.; Liszka, U.; Iruela-Arispe, M. L.; Jellinger, K.

    1991-01-01

    The expression of type VIII collagen was examined in the normal and diseased human brain. Focal immunoreactivity was seen in histologically abnormal vessels of all four angiomas and 40 of 52 brain tumours (gliomas, meningiomas and schwannomas). An extended staining pattern, as well as a punctate distribution, was frequently observed in affected vessels. Staining was not apparent in nine normal brains and in 15 pathologic brains showing various cerebrovascular abnormalities, including Alzheimer's, Leigh's and Wernicke's diseases. Immunoblotting of glioblastomas revealed two bands at 56 kD and 67 kD which were also present at low levels in normal frontal cortex. The extracellular distribution of type VIII collagen was different from that of the other collagen types which have been described in brain and resembles patterns of expression described for certain tissues during mammalian embryogenesis (Kapoor et al., 1988). Our results provide additional evidence for the participation of type VIII collagen in some types of angiogenesis. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 PMID:2003978

  2. Hybrid RGSA and Support Vector Machine Framework for Three-Dimensional Magnetic Resonance Brain Tumor Classification

    PubMed Central

    Rajesh Sharma, R.; Marikkannu, P.

    2015-01-01

    A novel hybrid approach for the identification of brain regions using magnetic resonance images accountable for brain tumor is presented in this paper. Classification of medical images is substantial in both clinical and research areas. Magnetic resonance imaging (MRI) modality outperforms towards diagnosing brain abnormalities like brain tumor, multiple sclerosis, hemorrhage, and many more. The primary objective of this work is to propose a three-dimensional (3D) novel brain tumor classification model using MRI images with both micro- and macroscale textures designed to differentiate the MRI of brain under two classes of lesion, benign and malignant. The design approach was initially preprocessed using 3D Gaussian filter. Based on VOI (volume of interest) of the image, features were extracted using 3D volumetric Square Centroid Lines Gray Level Distribution Method (SCLGM) along with 3D run length and cooccurrence matrix. The optimal features are selected using the proposed refined gravitational search algorithm (RGSA). Support vector machines, over backpropagation network, and k-nearest neighbor are used to evaluate the goodness of classifier approach. The preliminary evaluation of the system is performed using 320 real-time brain MRI images. The system is trained and tested by using a leave-one-case-out method. The performance of the classifier is tested using the receiver operating characteristic curve of 0.986 (±002). The experimental results demonstrate the systematic and efficient feature extraction and feature selection algorithm to the performance of state-of-the-art feature classification methods. PMID:26509188

  3. Brain tumor segmentation based on local independent projection-based classification.

    PubMed

    Huang, Meiyan; Yang, Wei; Wu, Yao; Jiang, Jun; Chen, Wufan; Feng, Qianjin

    2014-10-01

    Brain tumor segmentation is an important procedure for early tumor diagnosis and radiotherapy planning. Although numerous brain tumor segmentation methods have been presented, enhancing tumor segmentation methods is still challenging because brain tumor MRI images exhibit complex characteristics, such as high diversity in tumor appearance and ambiguous tumor boundaries. To address this problem, we propose a novel automatic tumor segmentation method for MRI images. This method treats tumor segmentation as a classification problem. Additionally, the local independent projection-based classification (LIPC) method is used to classify each voxel into different classes. A novel classification framework is derived by introducing the local independent projection into the classical classification model. Locality is important in the calculation of local independent projections for LIPC. Locality is also considered in determining whether local anchor embedding is more applicable in solving linear projection weights compared with other coding methods. Moreover, LIPC considers the data distribution of different classes by learning a softmax regression model, which can further improve classification performance. In this study, 80 brain tumor MRI images with ground truth data are used as training data and 40 images without ground truth data are used as testing data. The segmentation results of testing data are evaluated by an online evaluation tool. The average dice similarities of the proposed method for segmenting complete tumor, tumor core, and contrast-enhancing tumor on real patient data are 0.84, 0.685, and 0.585, respectively. These results are comparable to other state-of-the-art methods. PMID:24860022

  4. The Sum of Tumour-to-Brain Ratios Improves the Accuracy of Diagnosing Gliomas Using 18F-FET PET

    PubMed Central

    Zyromska, Agnieszka; Wisniewski, Tomasz; Harat, Aleksandra; Lopatto, Rita; Furtak, Jacek

    2015-01-01

    Gliomas are common brain tumours, but obtaining tissue for definitive diagnosis can be difficult. There is, therefore, interest in the use of non-invasive methods to diagnose and grade the disease. Although positron emission tomography (PET) with 18F-fluorethyltyrosine (18F-FET) can be used to differentiate between low-grade (LGG) and high-grade (HGG) gliomas, the optimal parameters to measure and their cut-points have yet to be established. We therefore assessed the value of single and dual time-point acquisition of 18F-FET PET parameters to differentiate between primary LGGs (n = 22) and HGGs (n = 24). PET examination was considered positive for glioma if the metabolic activity was 1.6-times higher than that of background (contralateral) brain, and maximum tissue-brain ratios (TBRmax) were calculated 10 and 60 min after isotope administration with their sums and differences calculated from individual time-point values. Using a threshold-based method, the overall sensitivity of PET was 97%. Several analysed parameters were significantly different between LGGs and HGGs. However, in a receiver operating characteristics analysis, TBR sum had the best diagnostic accuracy of 87% and sensitivity, specificity, and positive and negative predictive values of 100%, 72.7%, 80%, and 100%, respectively. 18F-FET PET is valuable for the non-invasive determination of glioma grade, especially when dual time-point metrics are used. TBR sum shows the greatest accuracy, sensitivity, and negative predictive value for tumour grade differentiation and is a simple method to implement. However, the cut-off may differ between institutions and calibration strategies would be useful. PMID:26468649

  5. Motor imagery classification by means of source analysis for brain-computer interface applications.

    PubMed

    Qin, Lei; Ding, Lei; He, Bin

    2004-09-01

    We report a pilot study of performing classification of motor imagery for brain-computer interface applications, by means of source analysis of scalp-recorded EEGs. Independent component analysis (ICA) was used as a spatio-temporal filter extracting signal components relevant to left or right motor imagery (MI) tasks. Source analysis methods including equivalent dipole analysis and cortical current density imaging were applied to reconstruct equivalent neural sources corresponding to MI, and classification was performed based on the inverse solutions. The classification was considered correct if the equivalent source was found over the motor cortex in the corresponding hemisphere. A classification rate of about 80% was achieved in the human subject studied using both the equivalent dipole analysis and the cortical current density imaging analysis. The present promising results suggest that the source analysis approach could manifest a clearer picture on the cortical activity, and thus facilitate the classification of MI tasks from scalp EEGs. PMID:15876632

  6. Motor imagery classification by means of source analysis for brain computer interface applications

    NASA Astrophysics Data System (ADS)

    Qin, Lei; Ding, Lei; He, Bin

    2004-09-01

    We report a pilot study of performing classification of motor imagery for brain-computer interface applications, by means of source analysis of scalp-recorded EEGs. Independent component analysis (ICA) was used as a spatio-temporal filter extracting signal components relevant to left or right motor imagery (MI) tasks. Source analysis methods including equivalent dipole analysis and cortical current density imaging were applied to reconstruct equivalent neural sources corresponding to MI, and classification was performed based on the inverse solutions. The classification was considered correct if the equivalent source was found over the motor cortex in the corresponding hemisphere. A classification rate of about 80% was achieved in the human subject studied using both the equivalent dipole analysis and the cortical current density imaging analysis. The present promising results suggest that the source analysis approach could manifest a clearer picture on the cortical activity, and thus facilitate the classification of MI tasks from scalp EEGs.

  7. Patterns of exposure to infectious diseases and social contacts in early life and risk of brain tumours in children and adolescents: an International Case–Control Study (CEFALO)

    PubMed Central

    Andersen, T V; Schmidt, L S; Poulsen, A H; Feychting, M; Röösli, M; Tynes, T; Aydin, D; Prochazka, M; Lannering, B; Klæboe, L; Eggen, T; Kuehni, C E; Schmiegelow, K; Schüz, J

    2013-01-01

    Background: Infectious diseases and social contacts in early life have been proposed to modulate brain tumour risk during late childhood and adolescence. Methods: CEFALO is an interview-based case–control study in Denmark, Norway, Sweden and Switzerland, including children and adolescents aged 7–19 years with primary intracranial brain tumours diagnosed between 2004 and 2008 and matched population controls. Results: The study included 352 cases (participation rate: 83%) and 646 controls (71%). There was no association with various measures of social contacts: daycare attendance, number of childhours at daycare, attending baby groups, birth order or living with other children. Cases of glioma and embryonal tumours had more frequent sick days with infections in the first 6 years of life compared with controls. In 7–19 year olds with 4+ monthly sick day, the respective odds ratios were 2.93 (95% confidence interval: 1.57–5.50) and 4.21 (95% confidence interval: 1.24–14.30). Interpretation: There was little support for the hypothesis that social contacts influence childhood and adolescent brain tumour risk. The association between reported sick days due to infections and risk of glioma and embryonal tumour may reflect involvement of immune functions, recall bias or inverse causality and deserve further attention. PMID:23652309

  8. Development of a decision support system for diagnosis and grading of brain tumours using in vivo magnetic resonance single voxel spectra.

    PubMed

    Tate, Anne R; Underwood, Joshua; Acosta, Dionisio M; Julià-Sapé, Margarida; Majós, Carles; Moreno-Torres, Angel; Howe, Franklyn A; van der Graaf, Marinette; Lefournier, Virginie; Murphy, Mary M; Loosemore, Alison; Ladroue, Christophe; Wesseling, Pieter; Luc Bosson, Jean; Cabañas, Miquel E; Simonetti, Arjan W; Gajewicz, Witold; Calvar, Jorge; Capdevila, Antoni; Wilkins, Peter R; Bell, B Anthony; Rémy, Chantal; Heerschap, Arend; Watson, Des; Griffiths, John R; Arús, Carles

    2006-06-01

    A computer-based decision support system to assist radiologists in diagnosing and grading brain tumours has been developed by the multi-centre INTERPRET project. Spectra from a database of 1H single-voxel spectra of different types of brain tumours, acquired in vivo from 334 patients at four different centres, are clustered according to their pathology, using automated pattern recognition techniques and the results are presented as a two-dimensional scatterplot using an intuitive graphical user interface (GUI). Formal quality control procedures were performed to standardize the performance of the instruments and check each spectrum, and teams of expert neuroradiologists, neurosurgeons, neurologists and neuropathologists clinically validated each case. The prototype decision support system (DSS) successfully classified 89% of the cases in an independent test set of 91 cases of the most frequent tumour types (meningiomas, low-grade gliomas and high-grade malignant tumours--glioblastomas and metastases). It also helps to resolve diagnostic difficulty in borderline cases. When the prototype was tested by radiologists and other clinicians it was favourably received. Results of the preliminary clinical analysis of the added value of using the DSS for brain tumour diagnosis with MRS showed a small but significant improvement over MRI used alone. In the comparison of individual pathologies, PNETs were significantly better diagnosed with the DSS than with MRI alone. PMID:16763971

  9. An investigation of human brain tumour lipids by high-resolution magic angle spinning 1H MRS and histological analysis.

    PubMed

    Opstad, Kirstie S; Bell, B Anthony; Griffiths, John R; Howe, Franklyn A

    2008-08-01

    NMR-visible lipid signals detected in vivo by 1H MRS are associated with tumour aggression and believed to arise from cytoplasmic lipid droplets. High-resolution magic angle spinning (HRMAS) 1H MRS and Nile Red staining were performed on human brain tumour biopsy specimens to investigate how NMR-visible lipid signals relate to viable cells and levels of necrosis across different grades of glioma. Presaturation spectra were acquired from 24 adult human astrocytoma biopsy samples of grades II (8), III (2) and IV (14) using HRMAS 1H MRS and quantified using LCModel to determine lipid concentrations. Each biopsy sample was then refrozen, cryostat sectioned, and stained with Nile Red, to determine the number of lipid droplets and droplet size distribution, and with Haematoxylin and Eosin, to determine cell density and percentage necrosis. A strong correlation (R=0.92, P<0.0001) was found between the number of Nile Red-stained droplets and the approximately 1.3 ppm lipid proton concentration by 1H MRS. Droplet sizes ranged from 1 to 10 microm in diameter, and the size distribution was constant independent of tumour grade. In the non-necrotic biopsy samples, the number of lipid droplets correlated with cell density, whereas in the necrotic samples, there were greater numbers of droplets that showed a positive correlation with percentage necrosis. The correlation between 1H MRS lipid signals and number of Nile Red-stained droplets, and the presence of lipid droplets in the non-necrotic biopsy specimens provide good evidence that the in vivo NMR-visible lipid signals are cytoplasmic in origin and that formation of lipid droplets precedes necrosis. PMID:18186027

  10. Brain tumours at 7T MRI compared to 3T—contrast effect after half and full standard contrast agent dose: initial results

    PubMed Central

    Noebauer-Huhmann, Iris-Melanie; Szomolanyi, P.; Kronnerwetter, C.; Widhalm, G.; Weber, M.; Nemec, S.; Juras, V.; Ladd, M. E.; Prayer, D.; Trattnig, S.

    2015-01-01

    Objectives To compare the contrast agent effect of a full dose and half the dose of gadobenate dimeglumine in brain tumours at 7 Tesla (7T) MR versus 3 Tesla (3T). Methods Ten patients with primary brain tumours or metastases were examined. Signal intensities were assessed in the lesion and normal brain. Tumour-to-brain contrast and lesion enhancement were calculated. Additionally, two independent readers subjectively graded the image quality and artefacts. Results The enhanced mean tumour-to-brain contrast and lesion enhancement were significantly higher at 7T than at 3T for both half the dose (91.8±45.8 vs. 43.9±25.3 [p=0.010], 128.1±53.7 vs. 75.5±32.4 [p=0.004]) and the full dose (129.2±50.9 vs. 66.6±33.1 [p=0.002], 165.4±54.2 vs. 102.6±45.4 [p=0.004]). Differences between dosages at each field strength were also significant. Lesion enhancement was higher with half the dose at 7T than with the full dose at 3T (p=.037), while the tumour-to-brain contrast was not significantly different. Subjectively, contrast enhancement, visibility, and lesion delineation were better at 7T and with the full dose. All parameters were rated as good, at the least. Conclusion Half the routine contrast agent dose at 7T provided higher lesion enhancement than the full dose at 3T which indicates the possibility of dose reduction at 7T. PMID:25194707

  11. Extracting regional brain patterns for classification of neurodegenerative diseases

    NASA Astrophysics Data System (ADS)

    Pulido, Andrea; Rueda, Andrea; Romero, Eduardo

    2013-11-01

    In structural Magnetic Resonance Imaging (MRI), neurodegenerative diseases generally present complex brain patterns that can be correlated with di erent clinical onsets of this pathologies. An objective method that aims to determine both global and local changes is not usually available in clinical practice, thus the interpretation of these images is strongly dependent on the radiologist's skills. In this paper, we propose a strategy which interprets the brain structure using a framework that highlights discriminant brain patterns for neurodegenerative diseases. This is accomplished by combining a probabilistic learning technique, which identi es and groups regions with similar visual features, with a visual saliency method that exposes relevant information within each region. The association of such patterns with a speci c disease is herein evaluated in a classi cation task, using a dataset including 80 Alzheimer's disease (AD) patients and 76 healthy subjects (NC). Preliminary results show that the proposed method reaches a maximum classi cation accuracy of 81.39%.

  12. In-phantom two-dimensional thermal neutron distribution for intraoperative boron neutron capture therapy of brain tumours

    NASA Astrophysics Data System (ADS)

    Yamamoto, T.; Matsumura, A.; Yamamoto, K.; Kumada, H.; Shibata, Y.; Nose, T.

    2002-07-01

    The aim of this study was to determine the in-phantom thermal neutron distribution derived from neutron beams for intraoperative boron neutron capture therapy (IOBNCT). Gold activation wires arranged in a cylindrical water phantom with (void-in-phantom) or without (standard phantom) a cylinder styrene form placed inside were irradiated by using the epithermal beam (ENB) and the mixed thermal-epithermal beam (TNB-1) at the Japan Research Reactor No 4. With ENB, we observed a flattened distribution of thermal neutron flux and a significantly enhanced thermal flux delivery at a depth compared with the results of using TNB-1. The thermal neutron distribution derived from both the ENB and TNB-1 was significantly improved in the void-in-phantom, and a double high dose area was formed lateral to the void. The flattened distribution in the circumference of the void was observed with the combination of ENB and the void-in-phantom. The measurement data suggest that the ENB may provide a clinical advantage in the form of an enhanced and flattened dose delivery to the marginal tissue of a post-operative cavity in which a residual and/or microscopically infiltrating tumour often occurs. The combination of the epithermal neutron beam and IOBNCT will improve the clinical results of BNCT for brain tumours.

  13. Multiple instance learning for classification of dementia in brain MRI.

    PubMed

    Tong, Tong; Wolz, Robin; Gao, Qinquan; Hajnal, Joseph V; Rueckert, Daniel

    2013-01-01

    Machine learning techniques have been widely used to support the diagnosis of neurological diseases such as dementia. Recent approaches utilize local intensity patterns within patches to derive voxelwise grading measures of disease. However, the relationships among these patches are usually ignored. In addition, there is some ambiguity in assigning disease labels to the extracted patches. Not all of the patches extracted from patients with dementia are characteristic of morphology associated with disease. In this paper, we propose to use a multiple instance learning method to address the problem of assigning training labels to the patches. In addition, a graph is built for each image to exploit the relationships among these patches, which aids the classification work. We illustrate the proposed approach in an application for the detection of Alzheimer's disease (AD): Using the baseline MR images of 834 subjects from the ADNI study, the proposed method can achieve a classification accuracy of 88.8% between AD patients and healthy controls, and 69.6% between patients with stable Mild Cognitive Impairment (MCI) and progressive MCI. These results compare favourably with state-of-the-art classification methods. PMID:24579190

  14. Adaptive classification on brain-computer interfaces using reinforcement signals.

    PubMed

    Llera, A; Gómez, V; Kappen, H J

    2012-11-01

    We introduce a probabilistic model that combines a classifier with an extra reinforcement signal (RS) encoding the probability of an erroneous feedback being delivered by the classifier. This representation computes the class probabilities given the task related features and the reinforcement signal. Using expectation maximization (EM) to estimate the parameter values under such a model shows that some existing adaptive classifiers are particular cases of such an EM algorithm. Further, we present a new algorithm for adaptive classification, which we call constrained means adaptive classifier, and show using EEG data and simulated RS that this classifier is able to significantly outperform state-of-the-art adaptive classifiers. PMID:22845827

  15. Development of a new autofluorescence probe for the analysis of normal and tumour brain tissues

    NASA Astrophysics Data System (ADS)

    Siebert, R.; Vu Thi, M. H.; Jean, F.; Charon, Y.; Collado-Hilly, M.; Duval, M. A.; Mandat, T.; Menard, L.; Palfi, S.; Tordjmann, T.

    2008-04-01

    Fluorescence spectroscopy of endogenous emission of brain tumors, in particular glioblastoma multiforme, will be used for intraoperative localization of brain tumor margins. Our future surgeon's probe aims to discriminate tumor from normal brain tissues using beta and autofluorescence detection at the same time. Within this study we have implemented C6 glioma cells into rat brains to analyze the endogenous fluorescence of tumor and normal rat brain tissue. Systematic differences have been observed when comparing the autofluorescence spectra obtained from white and grey matters: both the fluorescence intensity and the shape of the spectra differ. These results were obtained by means of a 2-fiber probe, one used to guide the laser to the tissue, the other for fluorescence light collection. Excitation light was delivered by a 405 nm picosecond laser and fluorescence detection was realized by a CCD-camera. In parallel we have developed brain phantoms allowing systematic analysis of fiber - sample geometries. Based on gelatin gels, they include silica particles with 235 and 329 nm diameters to simulate the diffusion characteristics of the tissue, ink for the absorption characteristics of the tissue and organic dyes like Rhodamin B to replace biofluorophores.

  16. Preliminary structural MRI based brain classification of chronic pelvic pain: A MAPP Network Study

    PubMed Central

    Bagarinao, Epifanio; Johnson, Kevin A.; Martucci, Katherine T.; Ichesco, Eric; Farmer, Melissa A.; Labus, Jennifer; Ness, Timothy J.; Harris, Richard; Deutsch, Georg; Apkarian, A. Vania; Mayer, Emeran A.; Clauw, Daniel J.; Mackey, Sean

    2014-01-01

    Neuroimaging studies have shown that changes in brain morphology often accompany chronic pain conditions. However, brain biomarkers that are sensitive and specific to chronic pelvic pain (CPP) have not yet been adequately identified. Using data from the Trans-MAPP Research Network, we examined the changes in brain morphology associated with CPP. We used a multivariate pattern classification approach to detect these changes and to identify patterns that could be used to distinguish participants with CPP from age-matched healthy controls. In particular, we used a linear support vector machine (SVM) algorithm to differentiate gray matter images from the two groups. Regions of positive SVM weight included several regions within the primary somatosensory cortex, pre-supplementary motor area, hippocampus, and amygdala were identified as important drivers of the classification with 73% overall accuracy. Thus, we have identified a preliminary classifier based on brain structure that is able to predict the presence of CPP with a good degree of predictive power. Our regional findings suggest that in individuals with CPP, greater gray matter density may be found in the identified distributed brain regions, which are consistent with some previous investigations in visceral pain syndromes. Future studies are needed to improve upon our identified preliminary classifier with integration of additional variables and to assess whether the observed differences in brain structure are unique to CPP or generalizable to other chronic pain conditions. PMID:25242566

  17. Improvement effect on the depth-dose distribution by CSF drainage and air infusion of a tumour-removed cavity in boron neutron capture therapy for malignant brain tumours

    NASA Astrophysics Data System (ADS)

    Sakurai, Yoshinori; Ono, Koji; Miyatake, Shin-ichi; Maruhashi, Akira

    2006-03-01

    Boron neutron capture therapy (BNCT) without craniotomy for malignant brain tumours was started using an epi-thermal neutron beam at the Kyoto University Reactor in June 2002. We have tried some techniques to overcome the treatable-depth limit in BNCT. One of the effective techniques is void formation utilizing a tumour-removed cavity. The tumorous part is removed by craniotomy about 1 week before a BNCT treatment in our protocol. Just before the BNCT irradiation, the cerebro-spinal fluid (CSF) in the tumour-removed cavity is drained out, air is infused to the cavity and then the void is made. This void improves the neutron penetration, and the thermal neutron flux at depth increases. The phantom experiments and survey simulations modelling the CSF drainage and air infusion of the tumour-removed cavity were performed for the size and shape of the void. The advantage of the CSF drainage and air infusion is confirmed for the improvement in the depth-dose distribution. From the parametric surveys, it was confirmed that the cavity volume had good correlation with the improvement effect, and the larger effect was expected as the cavity volume was larger.

  18. Classification of autism spectrum disorder using supervised learning of brain connectivity measures extracted from synchrostates

    NASA Astrophysics Data System (ADS)

    Jamal, Wasifa; Das, Saptarshi; Oprescu, Ioana-Anastasia; Maharatna, Koushik; Apicella, Fabio; Sicca, Federico

    2014-08-01

    Objective. The paper investigates the presence of autism using the functional brain connectivity measures derived from electro-encephalogram (EEG) of children during face perception tasks. Approach. Phase synchronized patterns from 128-channel EEG signals are obtained for typical children and children with autism spectrum disorder (ASD). The phase synchronized states or synchrostates temporally switch amongst themselves as an underlying process for the completion of a particular cognitive task. We used 12 subjects in each group (ASD and typical) for analyzing their EEG while processing fearful, happy and neutral faces. The minimal and maximally occurring synchrostates for each subject are chosen for extraction of brain connectivity features, which are used for classification between these two groups of subjects. Among different supervised learning techniques, we here explored the discriminant analysis and support vector machine both with polynomial kernels for the classification task. Main results. The leave one out cross-validation of the classification algorithm gives 94.7% accuracy as the best performance with corresponding sensitivity and specificity values as 85.7% and 100% respectively. Significance. The proposed method gives high classification accuracies and outperforms other contemporary research results. The effectiveness of the proposed method for classification of autistic and typical children suggests the possibility of using it on a larger population to validate it for clinical practice.

  19. Localisation of motor areas in brain tumour patients: a comparison of preoperative [18F]FDG-PET and intraoperative cortical electrostimulation.

    PubMed

    Schreckenberger, M; Spetzger, U; Sabri, O; Meyer, P T; Zeggel, T; Zimny, M; Gilsbach, J; Buell, U

    2001-09-01

    Assessment of the exact spatial relation between tumour and adjacent functionally relevant brain areas is a primary tool in the presurgical planning in brain tumour patients. The purpose of this study was to compare a preoperative fluorine-18 fluorodeoxyglucose positron emission tomography ([18F]FDG PET) activation protocol in patients with tumours near the central area with the results of intraoperative direct cortical electrostimulation, and to determine whether non-invasive preoperative PET imaging can provide results equivalent to those achieved with the invasive neurosurgical "gold standard". In this prospective study, we examined 20 patients with various tumours of the central area, performing two PET scans (each 30 min after i.v. injection of 134-341 MBq [18F]FDG) in each patient: (1) a resting baseline scan and (2) an activation scan using a standardised motor task (finger tapping, foot stretching). Following PET/MRI realignment and normalisation to the whole brain counts, parametric images of the activation versus the rest study were calculated and pixels above categorical threshold values were projected to the individual MRI for bimodal assessment of morphology and function (PET/MRI overlay). Intraoperative direct cortical electrostimulation was performed using a Viking IV probe (5 pulses, each of 100 micros) and documented using a dedicated neuro navigation system. Results were compared with the preoperative PET findings. PET revealed significant activation of the contralateral primary motor cortex in 95% (19/20) of the brain tumour patients (hand activation 13/13, foot activation 6/7), showing a mean increase in normalised [18F]FDG uptake of 20.5% +/- 5.2% (hand activation task) and 17.2% +/- 2.5% (foot activation task). Additionally detected activation of the ipsilateral primary motor cortex was interpreted as a metabolic indication for interhemispheric compensational processes. Evaluation of the PET findings by cortical stimulation yielded a 94% sensitivity and a 95% specificity for identification of motor-associated brain areas. In conclusion, the findings indicate that a relatively simple and clinically available [18F]FDG PET activation protocol enables a sufficiently precise assessment of the local relation between the intracranial tumour and the adjacent motor cortex areas and may facilitate the presurgical planning of tumour resection. PMID:11585300

  20. L-phenylalanine preloading reduces the (10)B(n, ?)(7)Li dose to the normal brain by inhibiting the uptake of boronophenylalanine in boron neutron capture therapy for brain tumours.

    PubMed

    Watanabe, Tsubasa; Tanaka, Hiroki; Fukutani, Satoshi; Suzuki, Minoru; Hiraoka, Masahiro; Ono, Koji

    2016-01-01

    Boron neutron capture therapy (BNCT) is a cellular-level particle radiation therapy that combines the selective delivery of boron compounds to tumour tissue with neutron irradiation. Previously, high doses of one of the boron compounds used for BNCT, L-BPA, were found to reduce the boron-derived irradiation dose to the central nervous system. However, injection with a high dose of L-BPA is not feasible in clinical settings. We aimed to find an alternative method to improve the therapeutic efficacy of this therapy. We examined the effects of oral preloading with various analogues of L-BPA in a xenograft tumour model and found that high-dose L-phenylalanine reduced the accumulation of L-BPA in the normal brain relative to tumour tissue. As a result, the maximum irradiation dose in the normal brain was 19.2% lower in the L-phenylalanine group relative to the control group. This study provides a simple strategy to improve the therapeutic efficacy of conventional boron compounds for BNCT for brain tumours and the possibility to widen the indication of BNCT to various kinds of other tumours. PMID:26455769

  1. An Automated and Intelligent Medical Decision Support System for Brain MRI Scans Classification

    PubMed Central

    Siddiqui, Muhammad Faisal; Reza, Ahmed Wasif; Kanesan, Jeevan

    2015-01-01

    A wide interest has been observed in the medical health care applications that interpret neuroimaging scans by machine learning systems. This research proposes an intelligent, automatic, accurate, and robust classification technique to classify the human brain magnetic resonance image (MRI) as normal or abnormal, to cater down the human error during identifying the diseases in brain MRIs. In this study, fast discrete wavelet transform (DWT), principal component analysis (PCA), and least squares support vector machine (LS-SVM) are used as basic components. Firstly, fast DWT is employed to extract the salient features of brain MRI, followed by PCA, which reduces the dimensions of the features. These reduced feature vectors also shrink the memory storage consumption by 99.5%. At last, an advanced classification technique based on LS-SVM is applied to brain MR image classification using reduced features. For improving the efficiency, LS-SVM is used with non-linear radial basis function (RBF) kernel. The proposed algorithm intelligently determines the optimized values of the hyper-parameters of the RBF kernel and also applied k-fold stratified cross validation to enhance the generalization of the system. The method was tested by 340 patients’ benchmark datasets of T1-weighted and T2-weighted scans. From the analysis of experimental results and performance comparisons, it is observed that the proposed medical decision support system outperformed all other modern classifiers and achieves 100% accuracy rate (specificity/sensitivity 100%/100%). Furthermore, in terms of computation time, the proposed technique is significantly faster than the recent well-known methods, and it improves the efficiency by 71%, 3%, and 4% on feature extraction stage, feature reduction stage, and classification stage, respectively. These results indicate that the proposed well-trained machine learning system has the potential to make accurate predictions about brain abnormalities from the individual subjects, therefore, it can be used as a significant tool in clinical practice. PMID:26280918

  2. An Automated and Intelligent Medical Decision Support System for Brain MRI Scans Classification.

    PubMed

    Siddiqui, Muhammad Faisal; Reza, Ahmed Wasif; Kanesan, Jeevan

    2015-01-01

    A wide interest has been observed in the medical health care applications that interpret neuroimaging scans by machine learning systems. This research proposes an intelligent, automatic, accurate, and robust classification technique to classify the human brain magnetic resonance image (MRI) as normal or abnormal, to cater down the human error during identifying the diseases in brain MRIs. In this study, fast discrete wavelet transform (DWT), principal component analysis (PCA), and least squares support vector machine (LS-SVM) are used as basic components. Firstly, fast DWT is employed to extract the salient features of brain MRI, followed by PCA, which reduces the dimensions of the features. These reduced feature vectors also shrink the memory storage consumption by 99.5%. At last, an advanced classification technique based on LS-SVM is applied to brain MR image classification using reduced features. For improving the efficiency, LS-SVM is used with non-linear radial basis function (RBF) kernel. The proposed algorithm intelligently determines the optimized values of the hyper-parameters of the RBF kernel and also applied k-fold stratified cross validation to enhance the generalization of the system. The method was tested by 340 patients' benchmark datasets of T1-weighted and T2-weighted scans. From the analysis of experimental results and performance comparisons, it is observed that the proposed medical decision support system outperformed all other modern classifiers and achieves 100% accuracy rate (specificity/sensitivity 100%/100%). Furthermore, in terms of computation time, the proposed technique is significantly faster than the recent well-known methods, and it improves the efficiency by 71%, 3%, and 4% on feature extraction stage, feature reduction stage, and classification stage, respectively. These results indicate that the proposed well-trained machine learning system has the potential to make accurate predictions about brain abnormalities from the individual subjects, therefore, it can be used as a significant tool in clinical practice. PMID:26280918

  3. A role for the malignant brain tumour (MBT) domain protein LIN-61 in DNA double-strand break repair by homologous recombination.

    PubMed

    Johnson, Nicholas M; Lemmens, Bennie B L G; Tijsterman, Marcel

    2013-01-01

    Malignant brain tumour (MBT) domain proteins are transcriptional repressors that function within Polycomb complexes. Some MBT genes are tumour suppressors, but how they prevent tumourigenesis is unknown. The Caenorhabditis elegans MBT protein LIN-61 is a member of the synMuvB chromatin-remodelling proteins that control vulval development. Here we report a new role for LIN-61: it protects the genome by promoting homologous recombination (HR) for the repair of DNA double-strand breaks (DSBs). lin-61 mutants manifest numerous problems associated with defective HR in germ and somatic cells but remain proficient in meiotic recombination. They are hypersensitive to ionizing radiation and interstrand crosslinks but not UV light. Using a novel reporter system that monitors repair of a defined DSB in C. elegans somatic cells, we show that LIN-61 contributes to HR. The involvement of this MBT protein in HR raises the possibility that MBT-deficient tumours may also have defective DSB repair. PMID:23505385

  4. Non-target adjacent stimuli classification improves performance of classical ERP-based brain computer interface

    NASA Astrophysics Data System (ADS)

    Ceballos, G. A.; Hernández, L. F.

    2015-04-01

    Objective. The classical ERP-based speller, or P300 Speller, is one of the most commonly used paradigms in the field of Brain Computer Interfaces (BCI). Several alterations to the visual stimuli presentation system have been developed to avoid unfavorable effects elicited by adjacent stimuli. However, there has been little, if any, regard to useful information contained in responses to adjacent stimuli about spatial location of target symbols. This paper aims to demonstrate that combining the classification of non-target adjacent stimuli with standard classification (target versus non-target) significantly improves classical ERP-based speller efficiency. Approach. Four SWLDA classifiers were trained and combined with the standard classifier: the lower row, upper row, right column and left column classifiers. This new feature extraction procedure and the classification method were carried out on three open databases: the UAM P300 database (Universidad Autonoma Metropolitana, Mexico), BCI competition II (dataset IIb) and BCI competition III (dataset II). Main results. The inclusion of the classification of non-target adjacent stimuli improves target classification in the classical row/column paradigm. A gain in mean single trial classification of 9.6% and an overall improvement of 25% in simulated spelling speed was achieved. Significance. We have provided further evidence that the ERPs produced by adjacent stimuli present discriminable features, which could provide additional information about the spatial location of intended symbols. This work promotes the searching of information on the peripheral stimulation responses to improve the performance of emerging visual ERP-based spellers.

  5. Simple adaptive sparse representation based classification schemes for EEG based brain-computer interface applications.

    PubMed

    Shin, Younghak; Lee, Seungchan; Ahn, Minkyu; Cho, Hohyun; Jun, Sung Chan; Lee, Heung-No

    2015-11-01

    One of the main problems related to electroencephalogram (EEG) based brain-computer interface (BCI) systems is the non-stationarity of the underlying EEG signals. This results in the deterioration of the classification performance during experimental sessions. Therefore, adaptive classification techniques are required for EEG based BCI applications. In this paper, we propose simple adaptive sparse representation based classification (SRC) schemes. Supervised and unsupervised dictionary update techniques for new test data and a dictionary modification method by using the incoherence measure of the training data are investigated. The proposed methods are very simple and additional computation for the re-training of the classifier is not needed. The proposed adaptive SRC schemes are evaluated using two BCI experimental datasets. The proposed methods are assessed by comparing classification results with the conventional SRC and other adaptive classification methods. On the basis of the results, we find that the proposed adaptive schemes show relatively improved classification accuracy as compared to conventional methods without requiring additional computation. PMID:26378500

  6. Assessing the performance of four different categories of histological criteria in brain tumours grading by means of a computer-aided diagnosis image analysis system.

    PubMed

    Kostopoulos, S; Konstandinou, C; Sidiropoulos, K; Ravazoula, P; Kalatzis, I; Asvestas, P; Cavouras, D; Glotsos, D

    2015-10-01

    Brain tumours are considered one of the most lethal and difficult to treat forms of cancer, with unknown aetiology and lack of any realistic screening. In this study, we examine, whether the combination of descriptive criteria, used by expert histopathologists in assessing histologic tissue samples, and quantitative image analysis features may improve the diagnostic accuracy of brain tumour grading. Data comprised 61 cases of brain cancers (astrocytomas, oligodendrogliomas, meningiomas) collected from the archives of the University Hospital of Patras, Greece. Incorporating physician's descriptive criteria and image analysis's quantitative features into a discriminant function, a computer-aided diagnosis system was designed for discriminating low-grade from high-grade brain tumours. Physician's descriptive features, when solely used in the system, proved of high discrimination accuracy (93.4%). When verbal descriptive features were combined with quantitative image analysis features in the system, discrimination accuracy improved to 98.4%. The generalization of the proposed system to unseen data converged to an overall prediction accuracy of 86.7% ± 5.4%. Considering that histological grading affects treatment selection and diagnostic errors may be notable in clinical practice, the utilization of the proposed system may safeguard against diagnostic misinterpretations in every day clinical practice. PMID:25974641

  7. Cerebral amyloid angiopathy (CAA) with presentation as a brain inflammatory pseudo-tumour.

    PubMed

    Polivka, M; Vallat, A V; Woimant, F; Lot, G; Boukobza, M; Guichard, J P; Mikol, J

    1999-01-01

    Cerebral amyloid angiopathy (CAA) is frequent but often asymptomatic. It can induce lobar haemorrhage, rapidly progressive dementia or recurrent transient neurological symptoms, other presentations being less frequent. We report 3 patients in their sixties presenting with a space occupying lesion which was the first manifestation of CAA. They were operated with a diagnosis of cerebral tumour. In all three cases, macroscopy was similar, the lesions were superficial in the cerebral cortex and the preoperative diagnoses were glioblastoma, meningioma and cavernoma. Histologically, the lesions consisted of a large inflammatory granuloma with numerous lipophages and siderophages surrounding capillaries with prominent endothelial cells. Vessels in the near cortex and meninges and within the granuloma harboured heavy amyloid deposits immunolabelled by anti-P component, anti-protein beta A4 with a A40 predominance and anti-apolipoprotein E. Adjacent cerebral cortex showed reactive gliosis and rare senile plaques. Amyloidosis is rarely considered among diagnoses of space occupying lesions. In our three cases, CT scan and MRI changes were related to the presence of an inflammatory granuloma around foci of haemorrhage and amyloid laden vessels. PMID:10812436

  8. Classification of Alzheimer's disease using regional saliency maps from brain MR volumes

    NASA Astrophysics Data System (ADS)

    Pulido, Andrea; Rueda, Andrea; Romero, Eduardo

    2013-02-01

    Accurate diagnosis of Alzheimer's disease (AD) from structural Magnetic Resonance (MR) images is difficult due to the complex alteration of patterns in brain anatomy that could indicate the presence or absence of the pathology. Currently, an effective approach that allows to interpret the disease in terms of global and local changes is not available in the clinical practice. In this paper, we propose an approach for classification of brain MR images, based on finding pathology-related patterns through the identification of regional structural changes. The approach combines a probabilistic Latent Semantic Analysis (pLSA) technique, which allows to identify image regions through latent topics inferred from the brain MR slices, with a bottom-up Graph-Based Visual Saliency (GBVS) model, which calculates maps of relevant information per region. Regional saliency maps are finally combined into a single map on each slice, obtaining a master saliency map of each brain volume. The proposed approach includes a one-to-one comparison of the saliency maps which feeds a Support Vector Machine (SVM) classifier, to group test subjects into normal or probable AD subjects. A set of 156 brain MR images from healthy (76) and pathological (80) subjects, splitted into a training set (10 non-demented and 10 demented subjects) and one testing set (136 subjects), was used to evaluate the performance of the proposed approach. Preliminary results show that the proposed method reaches a maximum classification accuracy of 87.21%.

  9. Measuring brain lesion progression with a supervised tissue classification system.

    PubMed

    Zacharaki, Evangelia I; Kanterakis, Stathis; Bryan, R Nick; Davatzikos, Christos

    2008-01-01

    Brain lesions, especially White Matter Lesions (WMLs), are associated with cardiac and vascular disease, but also with normal aging. Quantitative analysis of WML in large clinical trials is becoming more and more important. In this paper, we present a computer-assisted WML segmentation method, based on local features extracted from conventional multi-parametric Magnetic Resonance Imaging (MRI) sequences. A framework for preprocessing the temporal data by jointly equalizing histograms reduces the spatial and temporal variance of data, thereby improving the longitudinal stability of such measurements and hence the estimate of lesion progression. A Support Vector Machine (SVM) classifier trained on expert-defined WML's is applied for lesion segmentation on each scan using the AdaBoost algorithm. Validation on a population of 23 patients from 3 different imaging sites with follow-up studies and WMLs of varying sizes, shapes and locations tests the robustness and accuracy of the proposed segmentation method, compared to the manual segmentation results from an experienced neuroradiologist. The results show that our CAD-system achieves consistent lesion segmentation in the 4D data facilitating the disease monitoring. PMID:18979798

  10. Survival analysis for apparent diffusion coefficient measures in children with embryonal brain tumours

    PubMed Central

    Grech-Sollars, Matthew; Saunders, Dawn E.; Phipps, Kim P.; Clayden, Jonathan D.; Clark, Chris A.

    2012-01-01

    Embryonal brain tumors constitute a large and important subgroup of pediatric brain tumors. Apparent diffusion coefficient (ADC) measures have been previously used in the analysis of these tumors. We investigated a newly described ADC-derived parameter, the apparent transient coefficient in tumor (ATCT), a measure of the gradient change of ADC from the peri-tumoral edema into the tumor core, to study whether ATCT correlates with survival outcome. Sixty-one patients with histologically proven embryonal brain tumors and who had diffusion-weighted imaging (DWI) as part of their clinical imaging were enrolled in a retrospective study correlating ADC measures with survival. Kaplan-Meier survival curves were constructed for extent of surgical resection, age <3 years at diagnosis, tumor type, and metastasis at presentation. A multivariate survival analysis was performed that took into consideration ATCT and variables found to be significant in the Kaplan-Meier analysis as covariates. Results from the multivariate analysis showed that ATCT was the only significant covariate (P < .001). Survival analysis using Kaplan-Meier curves, dividing the patients into 4 groups of increasing values of ATCT, showed that more negative values of ATCT were significantly associated with a poorer prognosis (P < .001). A statistically significant difference was observed for survival data with respect to the change in ADC from edema into the tumor volume. Results show that more negative ATCT values are significantly associated with a poorer survival among children with embryonal brain tumors, irrespective of tumor type, extent of resection, age <3 years at diagnosis, and metastasis at presentation. PMID:22954494

  11. Classification of brain compartments and head injury lesions by neural networks applied to MRI.

    PubMed

    Kischell, E R; Kehtarnavaz, N; Hillman, G R; Levin, H; Lilly, M; Kent, T A

    1995-10-01

    An automatic, neural network-based approach was applied to segment normal brain compartments and lesions on MR images. Two supervised networks, backpropagation (BPN) and counterpropagation, and two unsupervised networks, Kohonen learning vector quantizer and analog adaptive resonance theory, were trained on registered T2-weighted and proton density images. The classes of interest were background, gray matter, white matter, cerebrospinal fluid, macrocystic encephalomalacia, gliosis, and "unknown." A comprehensive feature vector was chosen to discriminate these classes. The BPN combined with feature conditioning, multiple discriminant analysis followed by Hotelling transform, produced the most accurate and consistent classification results. Classification of normal brain compartments were generally in agreement with expert interpretation of the images. Macrocystic encephalomalacia and gliosis were recognized and, except around the periphery, classified in agreement with the clinician's report used to train the neural network. PMID:8570048

  12. Classification of normal and pathological aging processes based on brain MRI morphology measures

    NASA Astrophysics Data System (ADS)

    Perez-Gonzalez, J. L.; Yanez-Suarez, O.; Medina-Bañuelos, V.

    2014-03-01

    Reported studies describing normal and abnormal aging based on anatomical MRI analysis do not consider morphological brain changes, but only volumetric measures to distinguish among these processes. This work presents a classification scheme, based both on size and shape features extracted from brain volumes, to determine different aging stages: healthy control (HC) adults, mild cognitive impairment (MCI), and Alzheimer's disease (AD). Three support vector machines were optimized and validated for the pair-wise separation of these three classes, using selected features from a set of 3D discrete compactness measures and normalized volumes of several global and local anatomical structures. Our analysis show classification rates of up to 98.3% between HC and AD; of 85% between HC and MCI and of 93.3% for MCI and AD separation. These results outperform those reported in the literature and demonstrate the viability of the proposed morphological indexes to classify different aging stages.

  13. Enhanced Performance of Brain Tumor Classification via Tumor Region Augmentation and Partition

    PubMed Central

    Cheng, Jun; Huang, Wei; Cao, Shuangliang; Yang, Ru; Yang, Wei; Yun, Zhaoqiang; Wang, Zhijian; Feng, Qianjin

    2015-01-01

    Automatic classification of tissue types of region of interest (ROI) plays an important role in computer-aided diagnosis. In the current study, we focus on the classification of three types of brain tumors (i.e., meningioma, glioma, and pituitary tumor) in T1-weighted contrast-enhanced MRI (CE-MRI) images. Spatial pyramid matching (SPM), which splits the image into increasingly fine rectangular subregions and computes histograms of local features from each subregion, exhibits excellent results for natural scene classification. However, this approach is not applicable for brain tumors, because of the great variations in tumor shape and size. In this paper, we propose a method to enhance the classification performance. First, the augmented tumor region via image dilation is used as the ROI instead of the original tumor region because tumor surrounding tissues can also offer important clues for tumor types. Second, the augmented tumor region is split into increasingly fine ring-form subregions. We evaluate the efficacy of the proposed method on a large dataset with three feature extraction methods, namely, intensity histogram, gray level co-occurrence matrix (GLCM), and bag-of-words (BoW) model. Compared with using tumor region as ROI, using augmented tumor region as ROI improves the accuracies to 82.31% from 71.39%, 84.75% from 78.18%, and 88.19% from 83.54% for intensity histogram, GLCM, and BoW model, respectively. In addition to region augmentation, ring-form partition can further improve the accuracies up to 87.54%, 89.72%, and 91.28%. These experimental results demonstrate that the proposed method is feasible and effective for the classification of brain tumors in T1-weighted CE-MRI. PMID:26447861

  14. Functional connectivity classification of autism identifies highly predictive brain features but falls short of biomarker standards

    PubMed Central

    Plitt, Mark; Barnes, Kelly Anne; Martin, Alex

    2014-01-01

    Objectives Autism spectrum disorders (ASD) are diagnosed based on early-manifesting clinical symptoms, including markedly impaired social communication. We assessed the viability of resting-state functional MRI (rs-fMRI) connectivity measures as diagnostic biomarkers for ASD and investigated which connectivity features are predictive of a diagnosis. Methods Rs-fMRI scans from 59 high functioning males with ASD and 59 age- and IQ-matched typically developing (TD) males were used to build a series of machine learning classifiers. Classification features were obtained using 3 sets of brain regions. Another set of classifiers was built from participants' scores on behavioral metrics. An additional age and IQ-matched cohort of 178 individuals (89 ASD; 89 TD) from the Autism Brain Imaging Data Exchange (ABIDE) open-access dataset (http://fcon_1000.projects.nitrc.org/indi/abide/) were included for replication. Results High classification accuracy was achieved through several rs-fMRI methods (peak accuracy 76.67%). However, classification via behavioral measures consistently surpassed rs-fMRI classifiers (peak accuracy 95.19%). The class probability estimates, P(ASD|fMRI data), from brain-based classifiers significantly correlated with scores on a measure of social functioning, the Social Responsiveness Scale (SRS), as did the most informative features from 2 of the 3 sets of brain-based features. The most informative connections predominantly originated from regions strongly associated with social functioning. Conclusions While individuals can be classified as having ASD with statistically significant accuracy from their rs-fMRI scans alone, this method falls short of biomarker standards. Classification methods provided further evidence that ASD functional connectivity is characterized by dysfunction of large-scale functional networks, particularly those involved in social information processing. PMID:25685703

  15. Feature Extraction from Subband Brain Signals and Its Classification

    NASA Astrophysics Data System (ADS)

    Mukul, Manoj Kumar; Matsuno, Fumitoshi

    This paper considers both the non-stationarity as well as independence/uncorrelated criteria along with the asymmetry ratio over the electroencephalogram (EEG) signals and proposes a hybrid approach of the signal preprocessing methods before the feature extraction. A filter bank approach of the discrete wavelet transform (DWT) is used to exploit the non-stationary characteristics of the EEG signals and it decomposes the raw EEG signals into the subbands of different center frequencies called as rhythm. A post processing of the selected subband by the AMUSE algorithm (a second order statistics based ICA/BSS algorithm) provides the separating matrix for each class of the movement imagery. In the subband domain the orthogonality as well as orthonormality criteria over the whitening matrix and separating matrix do not come respectively. The human brain has an asymmetrical structure. It has been observed that the ratio between the norms of the left and right class separating matrices should be different for better discrimination between these two classes. The alpha/beta band asymmetry ratio between the separating matrices of the left and right classes will provide the condition to select an appropriate multiplier. So we modify the estimated separating matrix by an appropriate multiplier in order to get the required asymmetry and extend the AMUSE algorithm in the subband domain. The desired subband is further subjected to the updated separating matrix to extract subband sub-components from each class. The extracted subband sub-components sources are further subjected to the feature extraction (power spectral density) step followed by the linear discriminant analysis (LDA).

  16. Wireless brain-machine interface using EEG and EOG: brain wave classification and robot control

    NASA Astrophysics Data System (ADS)

    Oh, Sechang; Kumar, Prashanth S.; Kwon, Hyeokjun; Varadan, Vijay K.

    2012-04-01

    A brain-machine interface (BMI) links a user's brain activity directly to an external device. It enables a person to control devices using only thought. Hence, it has gained significant interest in the design of assistive devices and systems for people with disabilities. In addition, BMI has also been proposed to replace humans with robots in the performance of dangerous tasks like explosives handling/diffusing, hazardous materials handling, fire fighting etc. There are mainly two types of BMI based on the measurement method of brain activity; invasive and non-invasive. Invasive BMI can provide pristine signals but it is expensive and surgery may lead to undesirable side effects. Recent advances in non-invasive BMI have opened the possibility of generating robust control signals from noisy brain activity signals like EEG and EOG. A practical implementation of a non-invasive BMI such as robot control requires: acquisition of brain signals with a robust wearable unit, noise filtering and signal processing, identification and extraction of relevant brain wave features and finally, an algorithm to determine control signals based on the wave features. In this work, we developed a wireless brain-machine interface with a small platform and established a BMI that can be used to control the movement of a robot by using the extracted features of the EEG and EOG signals. The system records and classifies EEG as alpha, beta, delta, and theta waves. The classified brain waves are then used to define the level of attention. The acceleration and deceleration or stopping of the robot is controlled based on the attention level of the wearer. In addition, the left and right movements of eye ball control the direction of the robot.

  17. Spatial cluster analysis of nanoscopically mapped serotonin receptors for classification of fixed brain tissue

    NASA Astrophysics Data System (ADS)

    Sams, Michael; Silye, Rene; Göhring, Janett; Muresan, Leila; Schilcher, Kurt; Jacak, Jaroslaw

    2014-01-01

    We present a cluster spatial analysis method using nanoscopic dSTORM images to determine changes in protein cluster distributions within brain tissue. Such methods are suitable to investigate human brain tissue and will help to achieve a deeper understanding of brain disease along with aiding drug development. Human brain tissue samples are usually treated postmortem via standard fixation protocols, which are established in clinical laboratories. Therefore, our localization microscopy-based method was adapted to characterize protein density and protein cluster localization in samples fixed using different protocols followed by common fluorescent immunohistochemistry techniques. The localization microscopy allows nanoscopic mapping of serotonin 5-HT1A receptor groups within a two-dimensional image of a brain tissue slice. These nanoscopically mapped proteins can be confined to clusters by applying the proposed statistical spatial analysis. Selected features of such clusters were subsequently used to characterize and classify the tissue. Samples were obtained from different types of patients, fixed with different preparation methods, and finally stored in a human tissue bank. To verify the proposed method, samples of a cryopreserved healthy brain have been compared with epitope-retrieved and paraffin-fixed tissues. Furthermore, samples of healthy brain tissues were compared with data obtained from patients suffering from mental illnesses (e.g., major depressive disorder). Our work demonstrates the applicability of localization microscopy and image analysis methods for comparison and classification of human brain tissues at a nanoscopic level. Furthermore, the presented workflow marks a unique technological advance in the characterization of protein distributions in brain tissue sections.

  18. Classification algorithms using multiple MRI features in mild traumatic brain injury

    PubMed Central

    Xue, Yuanyi; Kenul, Damon; Ge, Yulin; Grossman, Robert I.; Wang, Yao

    2014-01-01

    Objective: The purpose of this study was to develop an algorithm incorporating MRI metrics to classify patients with mild traumatic brain injury (mTBI) and controls. Methods: This was an institutional review board–approved, Health Insurance Portability and Accountability Act–compliant prospective study. We recruited patients with mTBI and healthy controls through the emergency department and general population. We acquired data on a 3.0T Siemens Trio magnet including conventional brain imaging, resting-state fMRI, diffusion-weighted imaging, and magnetic field correlation (MFC), and performed multifeature analysis using the following MRI metrics: mean kurtosis (MK) of thalamus, MFC of thalamus and frontal white matter, thalamocortical resting-state networks, and 5 regional gray matter and white matter volumes including the anterior cingulum and left frontal and temporal poles. Feature selection was performed using minimal-redundancy maximal-relevance. We used classifiers including support vector machine, naive Bayesian, Bayesian network, radial basis network, and multilayer perceptron to test maximal accuracy. Results: We studied 24 patients with mTBI and 26 controls. Best single-feature classification uses thalamic MK yielding 74% accuracy. Multifeature analysis yields 80% accuracy using the full feature set, and up to 86% accuracy using minimal-redundancy maximal-relevance feature selection (MK thalamus, right anterior cingulate volume, thalamic thickness, thalamocortical resting-state network, thalamic microscopic MFC, and sex). Conclusion: Multifeature analysis using diffusion-weighted imaging, MFC, fMRI, and volumetrics may aid in the classification of patients with mTBI compared with controls based on optimal feature selection and classification methods. Classification of evidence: This study provides Class III evidence that classification algorithms using multiple MRI features accurately identifies patients with mTBI as defined by American Congress of Rehabilitation Medicine criteria compared with healthy controls. PMID:25171930

  19. The INTERPRET Decision-Support System version 3.0 for evaluation of Magnetic Resonance Spectroscopy data from human brain tumours and other abnormal brain masses

    PubMed Central

    2010-01-01

    Background Proton Magnetic Resonance (MR) Spectroscopy (MRS) is a widely available technique for those clinical centres equipped with MR scanners. Unlike the rest of MR-based techniques, MRS yields not images but spectra of metabolites in the tissues. In pathological situations, the MRS profile changes and this has been particularly described for brain tumours. However, radiologists are frequently not familiar to the interpretation of MRS data and for this reason, the usefulness of decision-support systems (DSS) in MRS data analysis has been explored. Results This work presents the INTERPRET DSS version 3.0, analysing the improvements made from its first release in 2002. Version 3.0 is aimed to be a program that 1st, can be easily used with any new case from any MR scanner manufacturer and 2nd, improves the initial analysis capabilities of the first version. The main improvements are an embedded database, user accounts, more diagnostic discrimination capabilities and the possibility to analyse data acquired under additional data acquisition conditions. Other improvements include a customisable graphical user interface (GUI). Most diagnostic problems included have been addressed through a pattern-recognition based approach, in which classifiers based on linear discriminant analysis (LDA) were trained and tested. Conclusions The INTERPRET DSS 3.0 allows radiologists, medical physicists, biochemists or, generally speaking, any person with a minimum knowledge of what an MR spectrum is, to enter their own SV raw data, acquired at 1.5 T, and to analyse them. The system is expected to help in the categorisation of MR Spectra from abnormal brain masses. PMID:21114820

  20. Classification of mathematics deficiency using shape and scale analysis of 3D brain structures

    NASA Astrophysics Data System (ADS)

    Kurtek, Sebastian; Klassen, Eric; Gore, John C.; Ding, Zhaohua; Srivastava, Anuj

    2011-03-01

    We investigate the use of a recent technique for shape analysis of brain substructures in identifying learning disabilities in third-grade children. This Riemannian technique provides a quantification of differences in shapes of parameterized surfaces, using a distance that is invariant to rigid motions and re-parameterizations. Additionally, it provides an optimal registration across surfaces for improved matching and comparisons. We utilize an efficient gradient based method to obtain the optimal re-parameterizations of surfaces. In this study we consider 20 different substructures in the human brain and correlate the differences in their shapes with abnormalities manifested in deficiency of mathematical skills in 106 subjects. The selection of these structures is motivated in part by the past links between their shapes and cognitive skills, albeit in broader contexts. We have studied the use of both individual substructures and multiple structures jointly for disease classification. Using a leave-one-out nearest neighbor classifier, we obtained a 62.3% classification rate based on the shape of the left hippocampus. The use of multiple structures resulted in an improved classification rate of 71.4%.

  1. Chemotherapy for unresectable and recurrent intramedullary glial tumours in children. Brain Tumours Subcommittee of the French Society of Paediatric Oncology (SFOP).

    PubMed

    Doireau, V; Grill, J; Zerah, M; Lellouch-Tubiana, A; Couanet, D; Chastagner, P; Marchal, J C; Grignon, Y; Chouffai, Z; Kalifa, C

    1999-11-01

    Adjuvant treatment for intramedullary tumours is based on radiotherapy. The place of chemotherapy in this setting has yet to be determined. Between May 1992 and January 1998, eight children with unresectable or recurrent intramedullary glioma were treated with the BB SFOP protocol (a 16-month chemotherapy regimen with carboplatin, procarbazine, vincristine, cyclophosphamide, etoposide and cisplatin). Six children had progressive disease following incomplete surgery and two had a post-operative relapse. Three patients had leptomeningeal dissemination at the outset of chemotherapy. Seven of the eight children responded clinically and radiologically, while one remained stable. At the end of the BB SFOP protocol four children were in radiological complete remission. After a median follow-up of 3 years from the beginning of chemotherapy, all the children but one (who died from another cause) are alive. Five patients remain progression-free, without radiotherapy, 59, 55, 40, 35 and 16 months after the beginning of chemotherapy. The efficacy of this chemotherapy in patients with intramedullary glial tumours calls for further trials in this setting, especially in young children and patients with metastases. PMID:10555754

  2. Chemotherapy for unresectable and recurrent intramedullary glial tumours in children. Brain Tumours Subcommittee of the French Society of Paediatric Oncology (SFOP).

    TOXLINE Toxicology Bibliographic Information

    Doireau V; Grill J; Zerah M; Lellouch-Tubiana A; Couanet D; Chastagner P; Marchal JC; Grignon Y; Chouffai Z; Kalifa C

    1999-11-01

    Adjuvant treatment for intramedullary tumours is based on radiotherapy. The place of chemotherapy in this setting has yet to be determined. Between May 1992 and January 1998, eight children with unresectable or recurrent intramedullary glioma were treated with the BB SFOP protocol (a 16-month chemotherapy regimen with carboplatin, procarbazine, vincristine, cyclophosphamide, etoposide and cisplatin). Six children had progressive disease following incomplete surgery and two had a post-operative relapse. Three patients had leptomeningeal dissemination at the outset of chemotherapy. Seven of the eight children responded clinically and radiologically, while one remained stable. At the end of the BB SFOP protocol four children were in radiological complete remission. After a median follow-up of 3 years from the beginning of chemotherapy, all the children but one (who died from another cause) are alive. Five patients remain progression-free, without radiotherapy, 59, 55, 40, 35 and 16 months after the beginning of chemotherapy. The efficacy of this chemotherapy in patients with intramedullary glial tumours calls for further trials in this setting, especially in young children and patients with metastases.

  3. Classification of anatomical structures in MR brain images using fuzzy parameters.

    PubMed

    Algorri, Maria-Elena; Flores-Mangas, Fernando

    2004-09-01

    We present an algorithm that automatically segments and classifies the brain structures in a set of magnetic resonance (MR) brain images using expert information contained in a small subset of the image set. The algorithm is intended to do the segmentation and classification tasks mimicking the way a human expert would reason. The algorithm uses a knowledge base taken from a small subset of semiautomatically classified images that is combined with a set of fuzzy indexes that capture the experience and expectation a human expert uses during recognition tasks. The fuzzy indexes are tissue specific and spatial specific, in order to consider the biological variations in the tissues and the acquisition inhomogeneities through the image set. The brain structures are segmented and classified one at a time. For each brain structure the algorithm needs one semiautomatically classified image and makes one pass through the image set. The algorithm uses low-level image processing techniques on a pixel basis for the segmentations, then validates or corrects the segmentations, and makes the final classification decision using higher level criteria measured by the set of fuzzy indexes. We use single-echo MR images because of their high volumetric resolution; but even though we are working with only one image per brain slice, we have multiple sources of information on each pixel: absolute and relative positions in the image, gray level value, statistics of the pixel and its three-dimensional neighborhood and relation to its counterpart pixels in adjacent images. We have validated our algorithm for ease of use and precision both with clinical experts and with measurable error indexes over a Brainweb simulated MR set. PMID:15376508

  4. Feed-forward hierarchical model of the ventral visual stream applied to functional brain image classification.

    PubMed

    Keator, David B; Fallon, James H; Lakatos, Anita; Fowlkes, Charless C; Potkin, Steven G; Ihler, Alexander

    2014-01-01

    Functional brain imaging is a common tool in monitoring the progression of neurodegenerative and neurological disorders. Identifying functional brain imaging derived features that can accurately detect neurological disease is of primary importance to the medical community. Research in computer vision techniques to identify objects in photographs have reported high accuracies in that domain, but their direct applicability to identifying disease in functional imaging is still under investigation in the medical community. In particular, Serre et al. (: In: IEEE Conference on Computer Vision and Pattern Recognition (CVPR-05). pp 994-1000) introduced a biophysically inspired filtering method emulating visual processing in striate cortex which they applied to perform object recognition in photographs. In this work, the model described by Serre et al. [2005] is extended to three-dimensional volumetric images to perform signal detection in functional brain imaging (PET, SPECT). The filter outputs are used to train both neural network and logistic regression classifiers and tested on two distinct datasets: ADNI Alzheimer's disease 2-deoxy-D-glucose (FDG) PET and National Football League players Tc99m HMPAO SPECT. The filtering pipeline is analyzed to identify which steps are most important for classification accuracy. Our results compare favorably with other published classification results and outperform those of a blinded expert human rater, suggesting the utility of this approach. PMID:22847891

  5. Feed-forward Hierarchical Model of the Ventral Visual Stream Applied to Functional Brain Image Classification

    PubMed Central

    Keator, DB; Fallon, JH; Lakatos, A; Fowlkes, CC; Potkin, SG; Ihler, A

    2015-01-01

    Functional brain imaging is a common tool in monitoring the progression of neurodegenerative and neurological disorders. Identifying functional brain imaging derived features that can accurately detect neurological disease is of primary importance to the medical community. Research in computer vision techniques to identify objects in photographs have reported high accuracies in that domain, but their direct applicability to identifying disease in functional imaging is still under investigation in the medical community. In particular, Serre et al. (Serre, et al. 2005) introduced a biophysically inspired filtering method emulating visual processing in striate cortex which they applied to perform object recognition in photographs. In this work, the model described by Serre et al. is extended to 3D volumetric images to perform signal detection in functional brain imaging (PET, SPECT). The filter outputs are used to train both neural network and logistic regression classifiers and tested on two distinct datasets: ADNI Alzheimer’s disease 2-deoxy-D-glucose (FDG) PET and National Football League players Tc99m HMPAO SPECT. The filtering pipeline is analyzed to identify which steps are most important for classification accuracy. Our results compare favorably with other published classification results and outperform those of a blinded expert human rater, suggesting the utility of this approach. PMID:22847891

  6. Computational Classification Approach to Profile Neuron Subtypes from Brain Activity Mapping Data

    PubMed Central

    Li, Meng; Zhao, Fang; Lee, Jason; Wang, Dong; Kuang, Hui; Tsien, Joe Z.

    2015-01-01

    The analysis of cell type-specific activity patterns during behaviors is important for better understanding of how neural circuits generate cognition, but has not been well explored from in vivo neurophysiological datasets. Here, we describe a computational approach to uncover distinct cell subpopulations from in vivo neural spike datasets. This method, termed “inter-spike-interval classification-analysis” (ISICA), is comprised of four major steps: spike pattern feature-extraction, pre-clustering analysis, clustering classification, and unbiased classification-dimensionality selection. By using two key features of spike dynamic - namely, gamma distribution shape factors and a coefficient of variation of inter-spike interval - we show that this ISICA method provides invariant classification for dopaminergic neurons or CA1 pyramidal cell subtypes regardless of the brain states from which spike data were collected. Moreover, we show that these ISICA-classified neuron subtypes underlie distinct physiological functions. We demonstrate that the uncovered dopaminergic neuron subtypes encoded distinct aspects of fearful experiences such as valence or value, whereas distinct hippocampal CA1 pyramidal cells responded differentially to ketamine-induced anesthesia. This ISICA method should be useful to better data mining of large-scale in vivo neural datasets, leading to novel insights into circuit dynamics associated with cognitions. PMID:26212360

  7. Computerized "Learn-As-You-Go" classification of traumatic brain injuries using NEISS narrative data.

    PubMed

    Chen, Wei; Wheeler, Krista K; Lin, Simon; Huang, Yungui; Xiang, Huiyun

    2016-04-01

    One important routine task in injury research is to effectively classify injury circumstances into user-defined categories when using narrative text. However, traditional manual processes can be time consuming, and existing batch learning systems can be difficult to utilize by novice users. This study evaluates a "Learn-As-You-Go" machine-learning program. When using this program, the user trains classification models and interactively checks on accuracy until a desired threshold is reached. We examined the narrative text of traumatic brain injuries (TBIs) in the National Electronic Injury Surveillance System (NEISS) and classified TBIs into sport and non-sport categories. Our results suggest that the DUALIST "Learn-As-You-Go" program, which features a user-friendly online interface, is effective in injury narrative classification. In our study, the time frame to classify tens of thousands of narratives was reduced from a few days to minutes after approximately sixty minutes of training. PMID:26851618

  8. Neuropsychological Assessment of Individuals with Brain Tumor: Comparison of Approaches Used in the Classification of Impairment

    PubMed Central

    Dwan, Toni Maree; Ownsworth, Tamara; Chambers, Suzanne; Walker, David G.; Shum, David H. K.

    2015-01-01

    Approaches to classifying neuropsychological impairment after brain tumor vary according to testing level (individual tests, domains, or global index) and source of reference (i.e., norms, controls, and pre-morbid functioning). This study aimed to compare rates of impairment according to different classification approaches. Participants were 44 individuals (57% female) with a primary brain tumor diagnosis (mean age = 45.6 years) and 44 matched control participants (59% female, mean age = 44.5 years). All participants completed a test battery that assesses pre-morbid IQ (Wechsler adult reading test), attention/processing speed (digit span, trail making test A), memory (Hopkins verbal learning test-revised, Rey–Osterrieth complex figure-recall), and executive function (trail making test B, Rey–Osterrieth complex figure copy, controlled oral word association test). Results indicated that across the different sources of reference, 86–93% of participants were classified as impaired at a test-specific level, 61–73% were classified as impaired at a domain-specific level, and 32–50% were classified as impaired at a global level. Rates of impairment did not significantly differ according to source of reference (p > 0.05); however, at the individual participant level, classification based on estimated pre-morbid IQ was often inconsistent with classification based on the norms or controls. Participants with brain tumor performed significantly poorer than matched controls on tests of neuropsychological functioning, including executive function (p = 0.001) and memory (p < 0.001), but not attention/processing speed (p > 0.05). These results highlight the need to examine individuals’ performance across a multi-faceted neuropsychological test battery to avoid over- or under-estimation of impairment. PMID:25815271

  9. Classification

    ERIC Educational Resources Information Center

    Clary, Renee; Wandersee, James

    2013-01-01

    In this article, Renee Clary and James Wandersee describe the beginnings of "Classification," which lies at the very heart of science and depends upon pattern recognition. Clary and Wandersee approach patterns by first telling the story of the "Linnaean classification system," introduced by Carl Linnacus (1707-1778), who is…

  10. Classification

    ERIC Educational Resources Information Center

    Clary, Renee; Wandersee, James

    2013-01-01

    In this article, Renee Clary and James Wandersee describe the beginnings of "Classification," which lies at the very heart of science and depends upon pattern recognition. Clary and Wandersee approach patterns by first telling the story of the "Linnaean classification system," introduced by Carl Linnacus (1707-1778), who is…

  11. Threshold selection for classification of MR brain images by clustering method

    NASA Astrophysics Data System (ADS)

    Moldovanu, Simona; Obreja, Cristian; Moraru, Luminita

    2015-12-01

    Given a grey-intensity image, our method detects the optimal threshold for a suitable binarization of MR brain images. In MR brain image processing, the grey levels of pixels belonging to the object are not substantially different from the grey levels belonging to the background. Threshold optimization is an effective tool to separate objects from the background and further, in classification applications. This paper gives a detailed investigation on the selection of thresholds. Our method does not use the well-known method for binarization. Instead, we perform a simple threshold optimization which, in turn, will allow the best classification of the analyzed images into healthy and multiple sclerosis disease. The dissimilarity (or the distance between classes) has been established using the clustering method based on dendrograms. We tested our method using two classes of images: the first consists of 20 T2-weighted and 20 proton density PD-weighted scans from two healthy subjects and from two patients with multiple sclerosis. For each image and for each threshold, the number of the white pixels (or the area of white objects in binary image) has been determined. These pixel numbers represent the objects in clustering operation. The following optimum threshold values are obtained, T = 80 for PD images and T = 30 for T2w images. Each mentioned threshold separate clearly the clusters that belonging of the studied groups, healthy patient and multiple sclerosis disease.

  12. Clinical features of gastroenteropancreatic tumours

    PubMed Central

    Czarnywojtek, Agata; Bączyk, Maciej; Ziemnicka, Katarzyna; Fischbach, Jakub; Wrotkowska, Elżbieta; Ruchała, Marek

    2015-01-01

    Gastroenteropancreatic (GEP) endocrine tumours (carcinoids and pancreatic islet cell tumours) are composed of multipotent neuroendocrine cells that exhibit a unique ability to produce, store, and secrete biologically active substances and cause distinct clinical syndromes. The classification of GEP tumours as functioning or non-functioning is based on the presence of symptoms that accompany these syndromes secondary to the secretion of hormones, neuropeptides and/or neurotransmitters (functioning tumours). Non-functioning tumours are considered to be neoplasms of neuroendocrine differentiation that are not associated with obvious symptoms attributed to the hypersecretion of metabolically active substances. However, a number of these tumours are either capable of producing low levels of such substances, which can be detected by immunohistochemistry but are insufficient to cause symptoms related to a clinical syndrome, or alternatively, they may secrete substances that are either metabolically inactive or inappropriately processed. In some cases, GEP tumours are not associated with the production of any hormone or neurotransmitter. Both functioning and non-functioning tumours can also produce symptoms due to mass effects compressing vital surrounding structures. Gastroenteropancreatic tumours are usually classified further according to the anatomic site of origin: foregut (including respiratory tract, thymus, stomach, duodenum, and pancreas), midgut (including small intestine, appendix, and right colon), and hindgut (including transverse colon, sigmoid, and rectum). Within these subgroups the biological and clinical characteristics of the tumours vary considerably, but this classification is still in use because a significant number of previous studies, mainly observational, have used it extensively. PMID:26516377

  13. Voxel-based discriminant map classification on brain ventricles for Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Wang, Jingnan; de Haan, Gerard; Unay, Devrim; Soldea, Octavian; Ekin, Ahmet

    2009-02-01

    One major hallmark of the Alzheimer's disease (AD) is the loss of neurons in the brain. In many cases, medical experts use magnetic resonance imaging (MRI) to qualitatively measure the neuronal loss by the shrinkage or enlargement of the structures-of-interest. Brain ventricle is one of the popular choices. It is easily detectable in clinical MR images due to the high contrast of the cerebro-spinal fluid (CSF) with the rest of the parenchyma. Moreover, atrophy in any periventricular structure will directly lead to ventricle enlargement. For quantitative analysis, volume is the common choice. However, volume is a gross measure and it cannot capture the entire complexity of the anatomical shape. Since most existing shape descriptors are complex and difficult-to-reproduce, more straightforward and robust ways to extract ventricle shape features are preferred in the diagnosis. In this paper, a novel ventricle shape based classification method for Alzheimer's disease has been proposed. Training process is carried out to generate two probability maps for two training classes: healthy controls (HC) and AD patients. By subtracting the HC probability map from the AD probability map, we get a 3D ventricle discriminant map. Then a matching coefficient has been calculated between each training subject and the discriminant map. An adjustable cut-off point of the matching coefficients has been drawn for the two classes. Generally, the higher the cut-off point that has been drawn, the higher specificity can be achieved. However, it will result in relatively lower sensitivity and vice versa. The benchmarked results against volume based classification show that the area under the ROC curves for our proposed method is as high as 0.86 compared with only 0.71 for volume based classification method.

  14. Automated Glioblastoma Segmentation Based on a Multiparametric Structured Unsupervised Classification

    PubMed Central

    Juan-Albarracín, Javier; Fuster-Garcia, Elies; Manjón, José V.; Robles, Montserrat; Aparici, F.; Martí-Bonmatí, L.; García-Gómez, Juan M.

    2015-01-01

    Automatic brain tumour segmentation has become a key component for the future of brain tumour treatment. Currently, most of brain tumour segmentation approaches arise from the supervised learning standpoint, which requires a labelled training dataset from which to infer the models of the classes. The performance of these models is directly determined by the size and quality of the training corpus, whose retrieval becomes a tedious and time-consuming task. On the other hand, unsupervised approaches avoid these limitations but often do not reach comparable results than the supervised methods. In this sense, we propose an automated unsupervised method for brain tumour segmentation based on anatomical Magnetic Resonance (MR) images. Four unsupervised classification algorithms, grouped by their structured or non-structured condition, were evaluated within our pipeline. Considering the non-structured algorithms, we evaluated K-means, Fuzzy K-means and Gaussian Mixture Model (GMM), whereas as structured classification algorithms we evaluated Gaussian Hidden Markov Random Field (GHMRF). An automated postprocess based on a statistical approach supported by tissue probability maps is proposed to automatically identify the tumour classes after the segmentations. We evaluated our brain tumour segmentation method with the public BRAin Tumor Segmentation (BRATS) 2013 Test and Leaderboard datasets. Our approach based on the GMM model improves the results obtained by most of the supervised methods evaluated with the Leaderboard set and reaches the second position in the ranking. Our variant based on the GHMRF achieves the first position in the Test ranking of the unsupervised approaches and the seventh position in the general Test ranking, which confirms the method as a viable alternative for brain tumour segmentation. PMID:25978453

  15. Automated glioblastoma segmentation based on a multiparametric structured unsupervised classification.

    PubMed

    Juan-Albarracín, Javier; Fuster-Garcia, Elies; Manjón, José V; Robles, Montserrat; Aparici, F; Martí-Bonmatí, L; García-Gómez, Juan M

    2015-01-01

    Automatic brain tumour segmentation has become a key component for the future of brain tumour treatment. Currently, most of brain tumour segmentation approaches arise from the supervised learning standpoint, which requires a labelled training dataset from which to infer the models of the classes. The performance of these models is directly determined by the size and quality of the training corpus, whose retrieval becomes a tedious and time-consuming task. On the other hand, unsupervised approaches avoid these limitations but often do not reach comparable results than the supervised methods. In this sense, we propose an automated unsupervised method for brain tumour segmentation based on anatomical Magnetic Resonance (MR) images. Four unsupervised classification algorithms, grouped by their structured or non-structured condition, were evaluated within our pipeline. Considering the non-structured algorithms, we evaluated K-means, Fuzzy K-means and Gaussian Mixture Model (GMM), whereas as structured classification algorithms we evaluated Gaussian Hidden Markov Random Field (GHMRF). An automated postprocess based on a statistical approach supported by tissue probability maps is proposed to automatically identify the tumour classes after the segmentations. We evaluated our brain tumour segmentation method with the public BRAin Tumor Segmentation (BRATS) 2013 Test and Leaderboard datasets. Our approach based on the GMM model improves the results obtained by most of the supervised methods evaluated with the Leaderboard set and reaches the second position in the ranking. Our variant based on the GHMRF achieves the first position in the Test ranking of the unsupervised approaches and the seventh position in the general Test ranking, which confirms the method as a viable alternative for brain tumour segmentation. PMID:25978453

  16. New tissue priors for improved automated classification of subcortical brain structures on MRI.

    PubMed

    Lorio, S; Fresard, S; Adaszewski, S; Kherif, F; Chowdhury, R; Frackowiak, R S; Ashburner, J; Helms, G; Weiskopf, N; Lutti, A; Draganski, B

    2016-04-15

    Despite the constant improvement of algorithms for automated brain tissue classification, the accurate delineation of subcortical structures using magnetic resonance images (MRI) data remains challenging. The main difficulties arise from the low gray-white matter contrast of iron rich areas in T1-weighted (T1w) MRI data and from the lack of adequate priors for basal ganglia and thalamus. The most recent attempts to obtain such priors were based on cohorts with limited size that included subjects in a narrow age range, failing to account for age-related gray-white matter contrast changes. Aiming to improve the anatomical plausibility of automated brain tissue classification from T1w data, we have created new tissue probability maps for subcortical gray matter regions. Supported by atlas-derived spatial information, raters manually labeled subcortical structures in a cohort of healthy subjects using magnetization transfer saturation and R2* MRI maps, which feature optimal gray-white matter contrast in these areas. After assessment of inter-rater variability, the new tissue priors were tested on T1w data within the framework of voxel-based morphometry. The automated detection of gray matter in subcortical areas with our new probability maps was more anatomically plausible compared to the one derived with currently available priors. We provide evidence that the improved delineation compensates age-related bias in the segmentation of iron rich subcortical regions. The new tissue priors, allowing robust detection of basal ganglia and thalamus, have the potential to enhance the sensitivity of voxel-based morphometry in both healthy and diseased brains. PMID:26854557

  17. Hand posture classification using electrocorticography signals in the gamma band over human sensorimotor brain areas

    PubMed Central

    Chestek, Cynthia A.; Gilja, Vikash; Blabe, Christine H.; Foster, Brett L.; Shenoy, Krishna V.; Parvizi, Josef; Henderson, Jaimie M.

    2013-01-01

    Objective Brain machine interface systems translate recorded neural signals into command signals for assistive technology. In individuals with upper limb amputation or cervical spinal cord injury, the restoration of a useful hand grasp could significantly improve daily function. We sought to determine if electrocorticographic (ECoG) signals contain sufficient information to select among multiple hand postures for a prosthetic hand, orthotic, or functional electrical stimulation system. Approach We recorded ECoG signals from subdural macro- and microelectrodes implanted in motor areas of three participants who were undergoing inpatient monitoring for diagnosis and treatment of intractable epilepsy. Participants performed 5 distinct isometric hand postures, as well as 4 distinct finger movements. Several control experiments were attempted in order to remove sensory information from the classification results. Online experiments were performed with 2 participants. Main Results Classification rates were 68%, 84%, and 81% for correct identification of 5 isometric hand postures offline. Using 3 potential controls for removing sensory signals, error rates were approximately doubled on average (2.1×). A similar increase in errors (2.6×) was noted when the participant was asked to make simultaneous wrist movements along with the hand postures. In online experiments, fist versus rest was successfully classified on 97% of trials; the classification output drove a prosthetic hand. Online classification performance for a larger number of hand postures remained above chance, but substantially below offline performance. In addition, the long integration windows used would preclude the use of decoded signals for control of a BCI system. Significance These results suggest that ECoG is a plausible source of command signals for prosthetic grasp selection. Overall, avenues remain for improvement through better electrode designs and placement, better participant training, and characterization of non-stationarities such that ECoG could be a viable signal source for grasp control for amputees or individuals with paralysis. PMID:23369953

  18. Hand posture classification using electrocorticography signals in the gamma band over human sensorimotor brain areas

    NASA Astrophysics Data System (ADS)

    Chestek, Cynthia A.; Gilja, Vikash; Blabe, Christine H.; Foster, Brett L.; Shenoy, Krishna V.; Parvizi, Josef; Henderson, Jaimie M.

    2013-04-01

    Objective. Brain-machine interface systems translate recorded neural signals into command signals for assistive technology. In individuals with upper limb amputation or cervical spinal cord injury, the restoration of a useful hand grasp could significantly improve daily function. We sought to determine if electrocorticographic (ECoG) signals contain sufficient information to select among multiple hand postures for a prosthetic hand, orthotic, or functional electrical stimulation system.Approach. We recorded ECoG signals from subdural macro- and microelectrodes implanted in motor areas of three participants who were undergoing inpatient monitoring for diagnosis and treatment of intractable epilepsy. Participants performed five distinct isometric hand postures, as well as four distinct finger movements. Several control experiments were attempted in order to remove sensory information from the classification results. Online experiments were performed with two participants. Main results. Classification rates were 68%, 84% and 81% for correct identification of 5 isometric hand postures offline. Using 3 potential controls for removing sensory signals, error rates were approximately doubled on average (2.1×). A similar increase in errors (2.6×) was noted when the participant was asked to make simultaneous wrist movements along with the hand postures. In online experiments, fist versus rest was successfully classified on 97% of trials; the classification output drove a prosthetic hand. Online classification performance for a larger number of hand postures remained above chance, but substantially below offline performance. In addition, the long integration windows used would preclude the use of decoded signals for control of a BCI system. Significance. These results suggest that ECoG is a plausible source of command signals for prosthetic grasp selection. Overall, avenues remain for improvement through better electrode designs and placement, better participant training, and characterization of non-stationarities such that ECoG could be a viable signal source for grasp control for amputees or individuals with paralysis.

  19. Glomus tumour.

    PubMed

    Sethu, C; Sethu, A U

    2016-01-01

    Glomus tumours are rare tumours accounting for only 1-5% of soft tissue tumours of the hand. They are described classically in the subungual region. We present the case of a 32-year-old woman with a late diagnosis of a glomus tumour that had caused her excruciating pain. Clinical examination was positive for Hildreth's sign and the Love test. Magnetic resonance imaging delineated the tumour, which was excised and confirmed histologically. This case highlights the continued delay in diagnosis of glomus tumours as well as the use of imaging in diagnosis and planning of surgery. PMID:26688416

  20. EEG Subspace Analysis and Classification Using Principal Angles for Brain-Computer Interfaces

    NASA Astrophysics Data System (ADS)

    Ashari, Rehab Bahaaddin

    Brain-Computer Interfaces (BCIs) help paralyzed people who have lost some or all of their ability to communicate and control the outside environment from loss of voluntary muscle control. Most BCIs are based on the classification of multichannel electroencephalography (EEG) signals recorded from users as they respond to external stimuli or perform various mental activities. The classification process is fraught with difficulties caused by electrical noise, signal artifacts, and nonstationarity. One approach to reducing the effects of similar difficulties in other domains is the use of principal angles between subspaces, which has been applied mostly to video sequences. This dissertation studies and examines different ideas using principal angles and subspaces concepts. It introduces a novel mathematical approach for comparing sets of EEG signals for use in new BCI technology. The success of the presented results show that principal angles are also a useful approach to the classification of EEG signals that are recorded during a BCI typing application. In this application, the appearance of a subject's desired letter is detected by identifying a P300-wave within a one-second window of EEG following the flash of a letter. Smoothing the signals before using them is the only preprocessing step that was implemented in this study. The smoothing process based on minimizing the second derivative in time is implemented to increase the classification accuracy instead of using the bandpass filter that relies on assumptions on the frequency content of EEG. This study examines four different ways of removing outliers that are based on the principal angles and shows that the outlier removal methods did not help in the presented situations. One of the concepts that this dissertation focused on is the effect of the number of trials on the classification accuracies. The achievement of the good classification results by using a small number of trials starting from two trials only, should make this approach more appropriate for online BCI applications. In order to understand and test how EEG signals are different from one subject to another, different users are tested in this dissertation, some with motor impairments. Furthermore, the concept of transferring information between subjects is examined by training the approach on one subject and testing it on the other subject using the training subject's EEG subspaces to classify the testing subject's trials.

  1. The fine structure of blood vessels in ethylnitrosourea-induced tumours of the rat nervous system: with special reference to the breakdown of the blood-brain barrier.

    PubMed Central

    Cox, D. J.; Pilkington, G. J.; Lantos, P. L.

    1976-01-01

    The fine structure of capillaries in and around ethylnitrosourea-induced tumours, gliomas and schwannomas, was examined in rats. A great variation was observed in the severity of changes: the degree of abnormality depended on the histological type and size of the tumour and on the site of the capillaries within the neoplasm. Endothelial cells, basement membranes and pericytes all demonstrated changes in their fine structure. The most striking alterations occurred in the endothelial cells: luminal cell membranes, tight junctions and pinocytotic activity were all modified. The widened extracellular spaces, particularly around capillaries, were frequently seen to contain proteinaceous material and haematogenous cells. Invasion of these spaces by neoplastic cells, however, rarely occurred. Formation of new capillaries was indicated by the mitotic activity of endothelial cells. These changes in the blood vessels of cerebral tumours have an important role in the breakdown of the blood-brain barrier. Images Fig. 1 Fig. 2 Fig. 3a Fig. 3b Fig. 4a Fig. 4b Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 PMID:183804

  2. EEG Classification for Hybrid Brain-Computer Interface Using a Tensor Based Multiclass Multimodal Analysis Scheme

    PubMed Central

    Ji, Hongfei; Li, Jie; Lu, Rongrong; Gu, Rong; Cao, Lei; Gong, Xiaoliang

    2016-01-01

    Electroencephalogram- (EEG-) based brain-computer interface (BCI) systems usually utilize one type of changes in the dynamics of brain oscillations for control, such as event-related desynchronization/synchronization (ERD/ERS), steady state visual evoked potential (SSVEP), and P300 evoked potentials. There is a recent trend to detect more than one of these signals in one system to create a hybrid BCI. However, in this case, EEG data were always divided into groups and analyzed by the separate processing procedures. As a result, the interactive effects were ignored when different types of BCI tasks were executed simultaneously. In this work, we propose an improved tensor based multiclass multimodal scheme especially for hybrid BCI, in which EEG signals are denoted as multiway tensors, a nonredundant rank-one tensor decomposition model is proposed to obtain nonredundant tensor components, a weighted fisher criterion is designed to select multimodal discriminative patterns without ignoring the interactive effects, and support vector machine (SVM) is extended to multiclass classification. Experiment results suggest that the proposed scheme can not only identify the different changes in the dynamics of brain oscillations induced by different types of tasks but also capture the interactive effects of simultaneous tasks properly. Therefore, it has great potential use for hybrid BCI. PMID:26880873

  3. EEG Classification for Hybrid Brain-Computer Interface Using a Tensor Based Multiclass Multimodal Analysis Scheme.

    PubMed

    Ji, Hongfei; Li, Jie; Lu, Rongrong; Gu, Rong; Cao, Lei; Gong, Xiaoliang

    2016-01-01

    Electroencephalogram- (EEG-) based brain-computer interface (BCI) systems usually utilize one type of changes in the dynamics of brain oscillations for control, such as event-related desynchronization/synchronization (ERD/ERS), steady state visual evoked potential (SSVEP), and P300 evoked potentials. There is a recent trend to detect more than one of these signals in one system to create a hybrid BCI. However, in this case, EEG data were always divided into groups and analyzed by the separate processing procedures. As a result, the interactive effects were ignored when different types of BCI tasks were executed simultaneously. In this work, we propose an improved tensor based multiclass multimodal scheme especially for hybrid BCI, in which EEG signals are denoted as multiway tensors, a nonredundant rank-one tensor decomposition model is proposed to obtain nonredundant tensor components, a weighted fisher criterion is designed to select multimodal discriminative patterns without ignoring the interactive effects, and support vector machine (SVM) is extended to multiclass classification. Experiment results suggest that the proposed scheme can not only identify the different changes in the dynamics of brain oscillations induced by different types of tasks but also capture the interactive effects of simultaneous tasks properly. Therefore, it has great potential use for hybrid BCI. PMID:26880873

  4. Generation of brain tumours in mice by Cre-mediated recombination of neural progenitors in situ with the tamoxifen metabolite endoxifen.

    PubMed

    Benedykcinska, Anna; Ferreira, Andreia; Lau, Joanne; Broni, Jessica; Richard-Loendt, Angela; Henriquez, Nico V; Brandner, Sebastian

    2016-02-01

    Targeted cell- or region-specific gene recombination is widely used in the functional analysis of genes implicated in development and disease. In the brain, targeted gene recombination has become a mainstream approach to study neurodegeneration or tumorigenesis. The use of the Cre-loxP system to study tumorigenesis in the adult central nervous system (CNS) can be limited, when the promoter (such as GFAP) is also transiently expressed during development, which can result in the recombination of progenies of different lineages. Engineering of transgenic mice expressing Cre recombinase fused to a mutant of the human oestrogen receptor (ER) allows the circumvention of transient developmental Cre expression by inducing recombination in the adult organism. The recombination of loxP sequences occurs only in the presence of tamoxifen. Systemic administration of tamoxifen can, however, exhibit toxicity and might also recombine unwanted cell populations if the promoter driving Cre expression is active at the time of tamoxifen administration. Here, we report that a single site-specific injection of an active derivative of tamoxifen successfully activates Cre recombinase and selectively recombines tumour suppressor genes in neural progenitor cells of the subventricular zone in mice, and we demonstrate its application in a model for the generation of intrinsic brain tumours. PMID:26704996

  5. Generation of brain tumours in mice by Cre-mediated recombination of neural progenitors in situ with the tamoxifen metabolite endoxifen

    PubMed Central

    Benedykcinska, Anna; Ferreira, Andreia; Lau, Joanne; Broni, Jessica; Richard-Loendt, Angela; Henriquez, Nico V.; Brandner, Sebastian

    2016-01-01

    ABSTRACT Targeted cell- or region-specific gene recombination is widely used in the functional analysis of genes implicated in development and disease. In the brain, targeted gene recombination has become a mainstream approach to study neurodegeneration or tumorigenesis. The use of the Cre-loxP system to study tumorigenesis in the adult central nervous system (CNS) can be limited, when the promoter (such as GFAP) is also transiently expressed during development, which can result in the recombination of progenies of different lineages. Engineering of transgenic mice expressing Cre recombinase fused to a mutant of the human oestrogen receptor (ER) allows the circumvention of transient developmental Cre expression by inducing recombination in the adult organism. The recombination of loxP sequences occurs only in the presence of tamoxifen. Systemic administration of tamoxifen can, however, exhibit toxicity and might also recombine unwanted cell populations if the promoter driving Cre expression is active at the time of tamoxifen administration. Here, we report that a single site-specific injection of an active derivative of tamoxifen successfully activates Cre recombinase and selectively recombines tumour suppressor genes in neural progenitor cells of the subventricular zone in mice, and we demonstrate its application in a model for the generation of intrinsic brain tumours. PMID:26704996

  6. Improving the classification of brain tumors in mice with perturbation enhanced (PE)-MRSI.

    PubMed

    Simões, Rui Vasco; Ortega-Martorell, Sandra; Delgado-Goñi, Teresa; Le Fur, Yann; Pumarola, Martí; Candiota, Ana Paula; Martín, Juana; Stoyanova, Radka; Cozzone, Patrick J; Julià-Sapé, Margarida; Arús, Carles

    2012-02-01

    Classifiers based on statistical pattern recognition analysis of MRSI data are becoming important tools for the non-invasive diagnosis of human brain tumors. Here we investigate the potential interest of perturbation-enhanced MRSI (PE-MRSI), in this case acute hyperglycemia, for improving the discrimination between mouse brain MRS patterns of glioblastoma multiforme (GBM), oligodendroglioma (ODG), and non-tumor brain parenchyma (NT). Six GBM-bearing mice and three ODG-bearing mice were scanned at 7 Tesla by PRESS-MRSI with 12 and 136 ms echo-time, during euglycemia (Eug) and also during induced acute hyperglycemia (Hyp), generating altogether four datasets per animal (echo time + glycemic condition): 12Eug, 136Eug, 12Hyp, and 136Hyp. For classifier development all spectral vectors (spv) selected from the MRSI matrix were unit length normalized (UL2) and used either as a training set (76 GBM spv, four mice; 70 ODG spv, two mice; 54 NT spv) or as an independent testing set (61 GBM spv, two mice; 31 ODG, one mouse; 23 NT spv). All Fisher's LDA classifiers obtained were evaluated as far as their descriptive performance-correctly classified cases of the training set (bootstrapping)-and predictive accuracy-balanced error rate of independent testing set classification. MRSI-based classifiers at 12Hyp were consistently more efficient in separating GBM, ODG, and NT regions, with overall accuracies always >80% and up to 95-96%; remaining classifiers were within the 48-85% range. This was also confirmed by user-independent selection of training and testing sets, using leave-one-out (LOO). This highlights the potential interest of perturbation-enhanced MRSI protocols for improving the non-invasive characterization of preclinical brain tumors. PMID:22193155

  7. Case-control study of the association between malignant brain tumours diagnosed between 2007 and 2009 and mobile and cordless phone use.

    PubMed

    Hardell, Lennart; Carlberg, Michael; Söderqvist, Fredrik; Mild, Kjell Hansson

    2013-12-01

    Previous studies have shown a consistent association between long-term use of mobile and cordless phones and glioma and acoustic neuroma, but not for meningioma. When used these phones emit radiofrequency electromagnetic fields (RF-EMFs) and the brain is the main target organ for the handheld phone. The International Agency for Research on Cancer (IARC) classified in May, 2011 RF-EMF as a group 2B, i.e. a 'possible' human carcinogen. The aim of this study was to further explore the relationship between especially long-term (>10 years) use of wireless phones and the development of malignant brain tumours. We conducted a new case-control study of brain tumour cases of both genders aged 18-75 years and diagnosed during 2007-2009. One population-based control matched on gender and age (within 5 years) was used to each case. Here, we report on malignant cases including all available controls. Exposures on e.g. use of mobile phones and cordless phones were assessed by a self-administered questionnaire. Unconditional logistic regression analysis was performed, adjusting for age, gender, year of diagnosis and socio-economic index using the whole control sample. Of the cases with a malignant brain tumour, 87% (n=593) participated, and 85% (n=1,368) of controls in the whole study answered the questionnaire. The odds ratio (OR) for mobile phone use of the analogue type was 1.8, 95% confidence interval (CI)=1.04?3.3, increasing with >25 years of latency (time since first exposure) to an OR=3.3, 95% CI=1.6-6.9. Digital 2G mobile phone use rendered an OR=1.6, 95% CI=0.996-2.7, increasing with latency >15-20 years to an OR=2.1, 95% CI=1.2-3.6. The results for cordless phone use were OR=1.7, 95% CI=1.1-2.9, and, for latency of 15-20 years, the OR=2.1, 95% CI=1.2-3.8. Few participants had used a cordless phone for >20-25 years. Digital type of wireless phones (2G and 3G mobile phones, cordless phones) gave increased risk with latency >1-5 years, then a lower risk in the following latency groups, but again increasing risk with latency >15-20 years. Ipsilateral use resulted in a higher risk than contralateral mobile and cordless phone use. Higher ORs were calculated for tumours in the temporal and overlapping lobes. Using the meningioma cases in the same study as reference entity gave somewhat higher ORs indicating that the results were unlikely to be explained by recall or observational bias. This study confirmed previous results of an association between mobile and cordless phone use and malignant brain tumours. These findings provide support for the hypothesis that RF-EMFs play a role both in the initiation and promotion stages of carcinogenesis. PMID:24064953

  8. Brain fingerprinting classification concealed information test detects US Navy military medical information with P300.

    PubMed

    Farwell, Lawrence A; Richardson, Drew C; Richardson, Graham M; Furedy, John J

    2014-01-01

    A classification concealed information test (CIT) used the "brain fingerprinting" method of applying P300 event-related potential (ERP) in detecting information that is (1) acquired in real life and (2) unique to US Navy experts in military medicine. Military medicine experts and non-experts were asked to push buttons in response to three types of text stimuli. Targets contain known information relevant to military medicine, are identified to subjects as relevant, and require pushing one button. Subjects are told to push another button to all other stimuli. Probes contain concealed information relevant to military medicine, and are not identified to subjects. Irrelevants contain equally plausible, but incorrect/irrelevant information. Error rate was 0%. Median and mean statistical confidences for individual determinations were 99.9% with no indeterminates (results lacking sufficiently high statistical confidence to be classified). We compared error rate and statistical confidence for determinations of both information present and information absent produced by classification CIT (Is a probe ERP more similar to a target or to an irrelevant ERP?) vs. comparison CIT (Does a probe produce a larger ERP than an irrelevant?) using P300 plus the late negative component (LNP; together, P300-MERMER). Comparison CIT produced a significantly higher error rate (20%) and lower statistical confidences: mean 67%; information-absent mean was 28.9%, less than chance (50%). We compared analysis using P300 alone with the P300 + LNP. P300 alone produced the same 0% error rate but significantly lower statistical confidences. These findings add to the evidence that the brain fingerprinting methods as described here provide sufficient conditions to produce less than 1% error rate and greater than 95% median statistical confidence in a CIT on information obtained in the course of real life that is characteristic of individuals with specific training, expertise, or organizational affiliation. PMID:25565941

  9. Brain fingerprinting classification concealed information test detects US Navy military medical information with P300

    PubMed Central

    Farwell, Lawrence A.; Richardson, Drew C.; Richardson, Graham M.; Furedy, John J.

    2014-01-01

    A classification concealed information test (CIT) used the “brain fingerprinting” method of applying P300 event-related potential (ERP) in detecting information that is (1) acquired in real life and (2) unique to US Navy experts in military medicine. Military medicine experts and non-experts were asked to push buttons in response to three types of text stimuli. Targets contain known information relevant to military medicine, are identified to subjects as relevant, and require pushing one button. Subjects are told to push another button to all other stimuli. Probes contain concealed information relevant to military medicine, and are not identified to subjects. Irrelevants contain equally plausible, but incorrect/irrelevant information. Error rate was 0%. Median and mean statistical confidences for individual determinations were 99.9% with no indeterminates (results lacking sufficiently high statistical confidence to be classified). We compared error rate and statistical confidence for determinations of both information present and information absent produced by classification CIT (Is a probe ERP more similar to a target or to an irrelevant ERP?) vs. comparison CIT (Does a probe produce a larger ERP than an irrelevant?) using P300 plus the late negative component (LNP; together, P300-MERMER). Comparison CIT produced a significantly higher error rate (20%) and lower statistical confidences: mean 67%; information-absent mean was 28.9%, less than chance (50%). We compared analysis using P300 alone with the P300 + LNP. P300 alone produced the same 0% error rate but significantly lower statistical confidences. These findings add to the evidence that the brain fingerprinting methods as described here provide sufficient conditions to produce less than 1% error rate and greater than 95% median statistical confidence in a CIT on information obtained in the course of real life that is characteristic of individuals with specific training, expertise, or organizational affiliation. PMID:25565941

  10. Classification of brain tumor type and grade using MRI texture and shape in a machine learning scheme.

    PubMed

    Zacharaki, Evangelia I; Wang, Sumei; Chawla, Sanjeev; Soo Yoo, Dong; Wolf, Ronald; Melhem, Elias R; Davatzikos, Christos

    2009-12-01

    The objective of this study is to investigate the use of pattern classification methods for distinguishing different types of brain tumors, such as primary gliomas from metastases, and also for grading of gliomas. The availability of an automated computer analysis tool that is more objective than human readers can potentially lead to more reliable and reproducible brain tumor diagnostic procedures. A computer-assisted classification method combining conventional MRI and perfusion MRI is developed and used for differential diagnosis. The proposed scheme consists of several steps including region-of-interest definition, feature extraction, feature selection, and classification. The extracted features include tumor shape and intensity characteristics, as well as rotation invariant texture features. Feature subset selection is performed using support vector machines with recursive feature elimination. The method was applied on a population of 102 brain tumors histologically diagnosed as metastasis (24), meningiomas (4), gliomas World Health Organization grade II (22), gliomas World Health Organization grade III (18), and glioblastomas (34). The binary support vector machine classification accuracy, sensitivity, and specificity, assessed by leave-one-out cross-validation, were, respectively, 85%, 87%, and 79% for discrimination of metastases from gliomas and 88%, 85%, and 96% for discrimination of high-grade (grades III and IV) from low-grade (grade II) neoplasms. Multiclass classification was also performed via a one-vs-all voting scheme. PMID:19859947

  11. Robust volumetric texture classification of magnetic resonance images of the brain using local frequency descriptor.

    PubMed

    Maani, Rouzbeh; Kalra, Sanjay; Yang, Yee-Hong

    2014-10-01

    This paper presents a method for robust volumetric texture classification. It also proposes 2D and 3D gradient calculation methods designed to be robust to imaging effects and artifacts. Using the proposed 2D method, the gradient information is extracted on the XYZ orthogonal planes at each voxel and used to form a local coordinate system. The local coordinate system and the local 3D gradient computed by the proposed 3D gradient calculator are then used to define volumetric texture features. It is shown that the presented gradient calculation methods can be efficiently implemented by convolving with 2D and 3D kernels. The experimental results demonstrate that the proposed gradient operators and the texture features are robust to imaging effects and artifacts, such as blurriness and noise in 2D and 3D images. The proposed method is compared with three state-of- the-art volumetric texture classification methods the 3D gray level cooccurance matrix, 3D local binary patterns, and second orientation pyramid on magnetic resonance imaging data of the brain. The experimental results show the superiority of the proposed method in accuracy, robustness, and speed. PMID:25167550

  12. The Wechsler Adult Intelligence Scale-III and Malingering in Traumatic Brain Injury: Classification Accuracy in Known Groups

    ERIC Educational Resources Information Center

    Curtis, Kelly L.; Greve, Kevin W.; Bianchini, Kevin J.

    2009-01-01

    A known-groups design was used to determine the classification accuracy of Wechsler Adult Intelligence Scale-III (WAIS-III) variables in detecting malingered neurocognitive dysfunction (MND) in traumatic brain injury (TBI). TBI patients were classified into the following groups: (a) mild TBI not-MND (n = 26), (b) mild TBI MND (n = 31), and (c)…

  13. New approach for automatic classification of Alzheimer's disease, mild cognitive impairment and healthy brain magnetic resonance images

    PubMed Central

    Boukadoum, Mounir

    2014-01-01

    Explored is the utility of modelling brain magnetic resonance images as a fractal object for the classification of healthy brain images against those with Alzheimer's disease (AD) or mild cognitive impairment (MCI). More precisely, fractal multi-scale analysis is used to build feature vectors from the derived Hurst's exponents. These are then classified by support vector machines (SVMs). Three experiments were conducted: in the first the SVM was trained to classify AD against healthy images. In the second experiment, the SVM was trained to classify AD against MCI and, in the third experiment, a multiclass SVM was trained to classify all three types of images. The experimental results, using the 10-fold cross-validation technique, indicate that the SVM achieved 97.08% ± 0.05 correct classification rate, 98.09% ± 0.04 sensitivity and 96.07% ± 0.07 specificity for the classification of healthy against MCI images, thus outperforming recent works found in the literature. For the classification of MCI against AD, the SVM achieved 97.5% ± 0.04 correct classification rate, 100% sensitivity and 94.93% ± 0.08 specificity. The third experiment also showed that the multiclass SVM provided highly accurate classification results. The processing time for a given image was 25 s. These findings suggest that this approach is efficient and may be promising for clinical applications. PMID:26609373

  14. Classification of Peptides According to their Blood-Brain Barrier Influx.

    PubMed

    Stalmans, Sofie; Gevaert, Bert; Wynendaele, Evelien; Nielandt, Joachim; De Tre, Guy; Peremans, Kathelijne; Burvenich, Christian; De Spiegeleer, Bart

    2015-01-01

    An increasing number of studies demonstrate the ability of peptides to cross the blood-brain barrier (BBB), opening perspectives for a new class of therapeutics for central nervous system diseases. However, information on the BBB transport of peptides suffer from a wide variety in used methods and experimental set-up. Therefore, it is currently difficult, if not impossible, to classify peptides according to their BBB influx characteristics. To allow direct comparison of BBB influx results of peptides, we introduce a classification method and unified response for BBB influx transport of peptides. First, the results of BBB influx response types (i.e. Kin (MTR), Kin (Perfusion), Pin vitro and Pin vivo), which quantitatively express brain influx, were classified into five classes of BBB influx magnitude based on the distribution of these results for the individual response types. Then, these classes were converted to a BBBin-response, representing a scaled value ranging from zero (no influx) to ten (high influx), independent from the BBB influx response type from which it was derived. This unified response can immediately be applied for new BBB influx results of peptides and represents a ballpark figure for BBB influx and allows direct comparison and ranking of peptides independent of the response type. PMID:26095378

  15. MRI brain images healthy and pathological tissues classification with the aid of improved particle swarm optimization and neural network.

    PubMed

    Sheejakumari, V; Sankara Gomathi, B

    2015-01-01

    The advantages of magnetic resonance imaging (MRI) over other diagnostic imaging modalities are its higher spatial resolution and its better discrimination of soft tissue. In the previous tissues classification method, the healthy and pathological tissues are classified from the MRI brain images using HGANN. But the method lacks sensitivity and accuracy measures. The classification method is inadequate in its performance in terms of these two parameters. So, to avoid these drawbacks, a new classification method is proposed in this paper. Here, new tissues classification method is proposed with improved particle swarm optimization (IPSO) technique to classify the healthy and pathological tissues from the given MRI images. Our proposed classification method includes the same four stages, namely, tissue segmentation, feature extraction, heuristic feature selection, and tissue classification. The method is implemented and the results are analyzed in terms of various statistical performance measures. The results show the effectiveness of the proposed classification method in classifying the tissues and the achieved improvement in sensitivity and accuracy measures. Furthermore, the performance of the proposed technique is evaluated by comparing it with the other segmentation methods. PMID:25977706

  16. MRI Brain Images Healthy and Pathological Tissues Classification with the Aid of Improved Particle Swarm Optimization and Neural Network

    PubMed Central

    Sheejakumari, V.; Sankara Gomathi, B.

    2015-01-01

    The advantages of magnetic resonance imaging (MRI) over other diagnostic imaging modalities are its higher spatial resolution and its better discrimination of soft tissue. In the previous tissues classification method, the healthy and pathological tissues are classified from the MRI brain images using HGANN. But the method lacks sensitivity and accuracy measures. The classification method is inadequate in its performance in terms of these two parameters. So, to avoid these drawbacks, a new classification method is proposed in this paper. Here, new tissues classification method is proposed with improved particle swarm optimization (IPSO) technique to classify the healthy and pathological tissues from the given MRI images. Our proposed classification method includes the same four stages, namely, tissue segmentation, feature extraction, heuristic feature selection, and tissue classification. The method is implemented and the results are analyzed in terms of various statistical performance measures. The results show the effectiveness of the proposed classification method in classifying the tissues and the achieved improvement in sensitivity and accuracy measures. Furthermore, the performance of the proposed technique is evaluated by comparing it with the other segmentation methods. PMID:25977706

  17. Classification

    NASA Technical Reports Server (NTRS)

    Oza, Nikunj C.

    2011-01-01

    A supervised learning task involves constructing a mapping from input data (normally described by several features) to the appropriate outputs. Within supervised learning, one type of task is a classification learning task, in which each output is one or more classes to which the input belongs. In supervised learning, a set of training examples---examples with known output values---is used by a learning algorithm to generate a model. This model is intended to approximate the mapping between the inputs and outputs. This model can be used to generate predicted outputs for inputs that have not been seen before. For example, we may have data consisting of observations of sunspots. In a classification learning task, our goal may be to learn to classify sunspots into one of several types. Each example may correspond to one candidate sunspot with various measurements or just an image. A learning algorithm would use the supplied examples to generate a model that approximates the mapping between each supplied set of measurements and the type of sunspot. This model can then be used to classify previously unseen sunspots based on the candidate's measurements. This chapter discusses methods to perform machine learning, with examples involving astronomy.

  18. A toolbox for real-time subject-independent and subject-dependent classification of brain states from fMRI signals

    PubMed Central

    Rana, Mohit; Gupta, Nalin; Dalboni Da Rocha, Josue L.; Lee, Sangkyun; Sitaram, Ranganatha

    2013-01-01

    There is a recent increase in the use of multivariate analysis and pattern classification in prediction and real-time feedback of brain states from functional imaging signals and mapping of spatio-temporal patterns of brain activity. Here we present MANAS, a generalized software toolbox for performing online and offline classification of fMRI signals. MANAS has been developed using MATLAB, LIBSVM, and SVMlight packages to achieve a cross-platform environment. MANAS is targeted for neuroscience investigations and brain rehabilitation applications, based on neurofeedback and brain-computer interface (BCI) paradigms. MANAS provides two different approaches for real-time classification: subject dependent and subject independent classification. In this article, we present the methodology of real-time subject dependent and subject independent pattern classification of fMRI signals; the MANAS software architecture and subsystems; and finally demonstrate the use of the system with experimental results. PMID:24151454

  19. Animal models of tumour-associated epilepsy.

    PubMed

    Kirschstein, Timo; Köhling, Rüdiger

    2016-02-15

    Brain tumours cause a sizeable proportion of epilepsies in adulthood, and actually can be etiologically responsible also for childhood epilepsies. Conversely, seizures are often first clinical signs of a brain tumour. Nevertheless, several issues of brain-tumour associated seizures and epilepsies are far from understood, or clarified regarding clinical consensus. These include both the specific mechanisms of epileptogenesis related to different tumour types, the possible relationship between malignancy and seizure emergence, the interaction between tumour mass and surrounding neuronal networks, and - not least - the best treatment options depending on different tumour types. To investigate these issues, experimental models of tumour-induced epilepsies are necessary. This review concentrates on the description of currently used models, focusing on methodological aspects. It highlights advantages and shortcomings of these models, and identifies future experimental challenges. PMID:26092434

  20. Placental Tumour

    PubMed Central

    Al-Riyami, Nihal; Al-Hadabi, Rahma; Al-Dughaishi, Tamima; Al-Riyami, Marwa

    2013-01-01

    Placental tumours include placental chorioangiomas, teratomas, haemangiomas, and haematomas. Placental chorioangiomas are benign vascular tumours and are the most common placental tumours, with a prevalence of 1%. Large placental chorioangiomas are rare and may lead to pregnancy complications and poor perinatal outcomes. These complications include fetal anaemia, hydrops fetalis, fetal growth restriction, polyhydramnios, and preterm delivery. We report a case of a large placental chorioangioma, the antenatal management and the maternal and fetal outcomes. PMID:23984037

  1. Canadian Study of Determinants of Endometabolic Health in ChIlDrEn (CanDECIDE study): a cohort study protocol examining the mechanisms of obesity in survivors of childhood brain tumours

    PubMed Central

    Samaan, M Constantine; Thabane, Lehana; Burrow, Sarah; Dillenburg, Rejane F; Scheinemann, Katrin

    2013-01-01

    Background Childhood obesity has reached epidemic proportions and is impacting children's health globally. In adults, obesity is associated with chronic low-grade inflammation that leads to insulin resistance, which is one of the important mechanisms through which dysregulation of metabolism occurs. There is limited information available about the contribution of inflammation to metabolic health in obese children, and how individual and lifestyle factors impact this risk. One of the paediatric groups at risk of higher rates of obesity includes the survivors of childhood brain tumours. The aim of this study was to evaluate the mechanisms that contribute to inflammation in obese survivors of childhood brain tumours. Methods and analysis This is a prospective cohort study. We will recruit lean and obese survivors of childhood brain tumours, and a control group composed of lean and obese children with no history of tumours. We will measure circulating and urinary cytokine levels and cytokine gene expression in monocytes. In addition, the methylation patterns of cytokine genes and that of toll-like receptor genes will be evaluated. These will be correlated with individual and lifestyle factors including age, sex, ethnicity, puberty, body mass index, fasting lipid levels, insulin sensitivity, diet, exercise, sleep, stress and built environment. The sample size calculation showed that we need 25 participants per arm Ethics and dissemination This study has received ethics approval from the institutional review board. Once completed, we will publish this work in peer-reviewed journals and share the findings in presentations and posters in meetings. Discussion This study will permit the interrogation of inflammation as a contributor to obesity and its complications in obese survivors of childhood brain tumours and compare them with lean survivors and lean and obese controls with no history of tumours, which may help identify therapeutic and preventative interventions to combat the rising tide of obesity. PMID:23794554

  2. Mesenchymal tumours of the mediastinum-part II.

    PubMed

    den Bakker, Michael A; Marx, Alexander; Mukai, Kiyoshi; Ströbel, Philipp

    2015-11-01

    This is the second part of a two-part review on soft tissue tumours which may be encountered in the mediastinum. This review is based on the 2013 WHO classification of soft tissue tumours and the 2015 WHO classification of tumours of the lung, pleura, thymus and heart and provides an updated overview of mesenchymal tumours that have been reported in the mediastinum. PMID:26358060

  3. Pooled analysis of case-control studies on malignant brain tumours and the use of mobile and cordless phones including living and deceased subjects.

    PubMed

    Hardell, Lennart; Carlberg, Michael; Hansson Mild, Kjell

    2011-05-01

    We studied the association between use of mobile and cordless phones and malignant brain tumours. Pooled analysis was performed of two case-control studies on patients with malignant brain tumours diagnosed during 1997-2003 and matched controls alive at the time of study inclusion and one case-control study on deceased patients and controls diagnosed during the same time period. Cases and controls or relatives to deceased subjects were interviewed using a structured questionnaire. Replies were obtained for 1,251 (85%) cases and 2,438 (84%) controls. The risk increased with latency period and cumulative use in hours for both mobile and cordless phones. Highest risk was found for the most common type of glioma, astrocytoma, yielding in the >10 year latency group for mobile phone use odds ratio (OR) = 2.7, 95% confidence interval (CI) = 1.9-3.7 and cordless phone use OR = 1.8, 95% CI = 1.2-2.9. In a separate analysis, these phone types were independent risk factors for glioma. The risk for astrocytoma was highest in the group with first use of a wireless phone before the age of 20; mobile phone use OR = 4.9, 95% CI = 2.2-11, cordless phone use OR = 3.9, 95% CI = 1.7-8.7. In conclusion, an increased risk was found for glioma and use of mobile or cordless phone. The risk increased with latency time and cumulative use in hours and was highest in subjects with first use before the age of 20. PMID:21331446

  4. New Zealand adolescents’ cellphone and cordless phone user-habits: are they at increased risk of brain tumours already? A cross-sectional study

    PubMed Central

    2013-01-01

    Background Cellphone and cordless phone use is very prevalent among early adolescents, but the extent and types of use is not well documented. This paper explores how, and to what extent, New Zealand adolescents are typically using and exposed to active cellphones and cordless phones, and considers implications of this in relation to brain tumour risk, with reference to current research findings. Methods This cross-sectional study recruited 373 Year 7 and 8 school students with a mean age of 12.3 years (range 10.3-13.7 years) from the Wellington region of New Zealand. Participants completed a questionnaire and measured their normal body-to-phone texting distances. Main exposure-metrics included self-reported time spent with an active cellphone close to the body, estimated time and number of calls on both phone types, estimated and actual extent of SMS text-messaging, cellphone functions used and people texted. Statistical analyses used Pearson Chi2 tests and Pearson’s correlation coefficient (r). Analyses were undertaken using SPSS version 19.0. Results Both cellphones and cordless phones were used by approximately 90% of students. A third of participants had already used a cordless phone for ? 7 years. In 4 years from the survey to mid-2013, the cordless phone use of 6% of participants would equal that of the highest Interphone decile (? 1640 hours), at the surveyed rate of use. High cellphone use was related to cellphone location at night, being woken regularly, and being tired at school. More than a third of parents thought cellphones carried a moderate-to-high health risk for their child. Conclusions While cellphones were very popular for entertainment and social interaction via texting, cordless phones were most popular for calls. If their use continued at the reported rate, many would be at increased risk of specific brain tumours by their mid-teens, based on findings of the Interphone and Hardell-group studies. PMID:23302218

  5. [Bronchoscopic diagnosis of lung tumours].

    PubMed

    Salajka, F

    2001-08-01

    The role of diagnostic bronchoscopy in patients with lung tumours is to evaluate the presence, extent and character of endobronchial tumourous changes. Videobronchoscopes and ultrathin bronchoscopes introduced recently into clinical practice make more accurate evaluation of larger areas of the bronchial tree possible. The clinical impact of methods based on the principle of (auto)fluorescence is searched for. From sites affected with the tumour samples are taken for histological or cytological examination which in addition to evidence of a tumourous etiology specify the type of tumour. An integral part of the examination is staging when the extent of the tumour proper and the regional lymph nodes within the framework of the TNM classification is evaluated optically and by aimed sampling. Examination by endobronchial ultrasound makes it possible to assess more accurately the extent of tumourous affection in the bronchial wall or extrabronchially. The task of the brochologist is also to evaluate the possbility of bronchological intervention (laser, brachytherapy, stent etc.) for palliation of symptoms. Virtual bronchoscopy is the arteficial construction of the image of central airways created from CT scans which makes it possible to visualize sections of the central airways which are not accessible by bronchoscopy. Bronchoscopy is a method of fundamental importance for the diagnosis, therapy and control of complications and palliation of symptoms of lung tumours. This method cannot be replaced at the moment by any other method and its importance is apparent from the fact that the spectrum of bronchoscopic examinations in patients with lung tumours is steadily increasing. PMID:15633392

  6. In vivo PET evaluation in tumour-bearing rats of 2-[ 18F]fluoromethyl- L-phenylalanine as a new potential tracer for molecular imaging of brain and extra-cranial tumours in humans with PET

    NASA Astrophysics Data System (ADS)

    Kersemans, Ken; Bauwens, Matthias; Lahoutte, Tony; Bossuyt, Axel; Mertens, John

    2007-02-01

    The Na +-independent L-type LAT1 amino acid transport system for large and neutral amino acids has been shown to be expressed higher in tumour tissue relative to normal tissue and has been regarded as a key point for the development of new amino acid based tumour tracers for molecular imaging. We developed a new fluorinated phenylalanine analogue, 2-[ 18F]fluoromethyl- L-phenylalanine, considering that the spatial volume of FCH 3 is comparable with that of the iodine atom in 2-I- L-phenylalanine, of which we have proven that it is taken up excellently in tumours by the LAT1 system. The substrate molecule for radiolabeling, Boc-2-bromomethyl- L-phenylalanine- tButylester, was prepared by radical bromination of Boc-2-methyl- L-phenylalanine- tButylester. [ 18F -] for bromine exchange is performed within 3 min in conditions comparable to the [ 18F]FDG synthesis with a radiochemical yield of at least 85%. After deprotection and semi-preparative HPLC purification, the 2-[ 18F]fluoromethyl- L-phenylalanine is recovered n.c.a. (57%) with a high purity and 3.7 MBq were injected into R1M rhabdomyosarcoma tumour-bearing rats. Imaging was performed with a human PET camera from 5 to 45 min p.i. The tumour/background and tumour/blood ratios obtained from PET acquisition were at least 2.5. DUR values for the tumours were at least about 5. Furthermore, a small tumour implanted near a kidney could be well visualized completely separated from this kidney. Moreover in all tumours the "active" tumour tissue can clearly be differentiated from less active tumour tissue. This proves that 2-[ 18F]fluoromethyl- L-phenylalanine has a great potential as a new tracer for specific tumour diagnosis with PET.

  7. Multiclass classification of hemodynamic responses for performance improvement of functional near-infrared spectroscopy-based brain-computer interface

    NASA Astrophysics Data System (ADS)

    Shin, Jaeyoung; Jeong, Jichai

    2014-06-01

    We improved the performance of a functional near-infrared spectroscopy (fNIRS)-based brain-computer interface based on relatively short task duration and multiclass classification. A custom-built eight-channel fNIRS system was used over the motor cortex areas in both hemispheres to measure the hemodynamic responses evoked by four different motor tasks (overt execution of arm lifting and knee extension for both sides) instead of finger tapping. The hemodynamic responses were classified using the naive Bayes classifier. Among the mean, max, slope, variance, and median of the signal amplitude and the time lag of the signal, several signal features are chosen to obtain highest classification accuracy. Ten runs of threefold cross-validation were conducted, which yielded classification accuracies of 87.1%±2.4% to 95.5%±2.4%, 77.5%±1.9% to 92.4%±3.2%, and 73.8%±3.5% to 91.5%±1.4% for the binary, ternary, and quaternary classifications, respectively. Eight seconds of task duration for obtaining sufficient quaternary classification accuracy was suggested. The bit transfer rate per minute (BPM) based on the quaternary classification accuracy was investigated. A BPM can be achieved from 2.81 to 5.40 bits/min.

  8. Tumours of the thymus

    PubMed Central

    Sellors, T. Holmes; Thackray, A. C.; Thomson, A. D.

    1967-01-01

    Eighty-eight cases of thymoma are discussed with the object of trying to co-ordinate the histological and clinical features. The pathological specimens were in all cases obtained at operation. The pathology classification introduced by Thomson and Thackray in 1957 has been found to correspond adequately with the clinical pattern. The most common groups of tumours are basically epithelial and can be separated into five or six subdivisions, each of which has a separate pattern of behaviour. Lymphoid and teratomatous tumours also occur, but there were only two examples in this series. Clinically, separation of patients who suffered from myasthenia (38) and those who did not (50) affords the first main grouping. The majority of patients who had myasthenia gravis had tumours classified as epidermoid (19) and lymphoepithelial (14), the former with a more malignant appearance and behaviour than the latter. Removal of the tumour with or without radiation gave considerable and sometimes complete relief from myasthenic symptoms. Non-myasthenic thymoma (50) was usually discovered as a result of pressure signs or in the course of routine radiography. Spindle or oval celled tumours followed a benign pattern whereas undifferentiated thymoma was in every sense malignant, as also were teratomatous growths. Granulomatous or Hodgkin-like thymomas were of special interest and had an unpredictable course, some patients surviving many years after what was regarded as inadequate treatment. The place of radiotherapy as a pre- or post-operative agent complementary to surgery is discussed. Images PMID:6033387

  9. Impact of brain tumour location on emotion and personality: a voxel-based lesion-symptom mapping study on mentalization processes.

    PubMed

    Campanella, Fabio; Shallice, Tim; Ius, Tamara; Fabbro, Franco; Skrap, Miran

    2014-09-01

    Patients affected by brain tumours may show behavioural and emotional regulation deficits, sometimes showing flattened affect and sometimes experiencing a true 'change' in personality. However, little evidence is available to the surgeon as to what changes are likely to occur with damage at specific sites, as previous studies have either relied on single cases or provided only limited anatomical specificity, mostly reporting associations rather than dissociations of symptoms. We investigated these aspects in patients undergoing surgery for the removal of cerebral tumours. We argued that many of the problems described can be ascribed to the onset of difficulties in one or more of the different levels of the process of mentalizing (i.e. abstracting and reflecting upon) emotion and intentions, which impacts on everyday behaviour. These were investigated in terms of (i) emotion recognition; (ii) Theory of Mind; (iii) alexithymia; and (iv) self-maturity (personality disorder). We hypothesized that temporo/limbic areas would be critical for processing emotion and intentions at a more perceptual level, while frontal lobe structures would be more critical when higher levels of mentalization/abstraction are required. We administered four different tasks, Task 1: emotion recognition of Ekman faces; Task 2: the Eyes Test (Theory of Mind); Task 3: Toronto Alexithymia Scale; and Task 4: Temperament and Character Inventory (a personality inventory), both immediately before and few days after the operation for the removal of brain tumours in a series of 71 patients (age range: 18-75 years; 33 female) with lesions located in the left or right frontal, temporal and parietal lobes. Lobe-based and voxel-based analysis confirmed that tasks requiring interpretation of emotions and intentions at more basic (less mentalized) levels (Tasks 1 and 2) were more affected by temporo/insular lesions, with emotion recognition (Task 1) being maximally impaired by anterior temporal and amygdala lesions and Task 2 (found to be a 'basic' Theory of Mind task involving only limited mentalization) being mostly impaired by posterior temporoparietal lesions. Tasks relying on higher-level mentalization (Tasks 3 and 4) were maximally affected by prefrontal lesions, with the alexithymia scale (Task 3) being mostly associated with anterior/medial lesions and the self-maturity measure (Task 4) with lateral prefrontal ones. PMID:25027503

  10. Discriminative analysis of brain functional connectivity patterns for mental fatigue classification.

    PubMed

    Sun, Yu; Lim, Julian; Meng, Jianjun; Kwok, Kenneth; Thakor, Nitish; Bezerianos, Anastasios

    2014-10-01

    Mental fatigue is a commonly experienced state that can be induced by placing heavy demands on cognitive systems. This often leads to lowered productivity and increased safety risks. In this study, we developed a functional-connectivity based mental fatigue monitoring method. Twenty-six subjects underwent a 20-min mentally demanding test of sustained attention with high-resolution EEG monitoring. Functional connectivity patterns were obtained on the cortical surface via source localization of cortical activities in the first and last 5-min quartiles of the experiment. Multivariate pattern analysis was then adopted to extract the highly discriminative functional connectivity information. The algorithm used in the present study demonstrated an overall accuracy of 81.5% (p < 0.0001) for fatigue classification through leave-one-out cross validation. Moreover, we found that the most discriminative connectivity features were located in or across middle frontal gyrus and several motor areas, in agreement with the important role that these cortical regions play in the maintenance of sustained attention. This work therefore demonstrates the feasibility of a functional-connectivity-based mental fatigue assessment method, opening up a new avenue for modeling natural brain dynamics under different mental states. Our method has potential applications in several domains, including traffic and industrial safety. PMID:24962984

  11. Brain functional connectivity patterns for emotional state classification in Parkinson's disease patients without dementia.

    PubMed

    Yuvaraj, R; Murugappan, M; Acharya, U Rajendra; Adeli, Hojjat; Ibrahim, Norlinah Mohamed; Mesquita, Edgar

    2016-02-01

    Successful emotional communication is crucial for social interactions and social relationships. Parkinson's Disease (PD) patients have shown deficits in emotional recognition abilities although the research findings are inconclusive. This paper presents an investigation of six emotions (happiness, sadness, fear, anger, surprise, and disgust) of twenty non-demented (Mini-Mental State Examination score >24) PD patients and twenty Healthy Controls (HCs) using Electroencephalogram (EEG)-based Brain Functional Connectivity (BFC) patterns. The functional connectivity index feature in EEG signals is computed using three different methods: Correlation (COR), Coherence (COH), and Phase Synchronization Index (PSI). Further, a new functional connectivity index feature is proposed using bispectral analysis. The experimental results indicate that the BFC change is significantly different among emotional states of PD patients compared with HC. Also, the emotional connectivity pattern classified using Support Vector Machine (SVM) classifier yielded the highest accuracy for the new bispectral functional connectivity index. The PD patients showed emotional impairments as demonstrated by a poor classification performance. This finding suggests that decrease in the functional connectivity indices during emotional stimulation in PD, indicating functional disconnections between cortical areas. PMID:26515932

  12. Defining traumatic brain injury in children and youth using International Classification of Diseases version 10 codes: a systematic review protocol

    PubMed Central

    2013-01-01

    Background Although healthcare administrative data are commonly used for traumatic brain injury research, there is currently no consensus or consistency on using the International Classification of Diseases version 10 codes to define traumatic brain injury among children and youth. This protocol is for a systematic review of the literature to explore the range of International Classification of Diseases version 10 codes that are used to define traumatic brain injury in this population. Methods/design The databases MEDLINE, MEDLINE In-Process, Embase, PsychINFO, CINAHL, SPORTDiscus, and Cochrane Database of Systematic Reviews will be systematically searched. Grey literature will be searched using Grey Matters and Google. Reference lists of included articles will also be searched. Articles will be screened using predefined inclusion and exclusion criteria and all full-text articles that meet the predefined inclusion criteria will be included for analysis. The study selection process and reasons for exclusion at the full-text level will be presented using a PRISMA study flow diagram. Information on the data source of included studies, year and location of study, age of study population, range of incidence, and study purpose will be abstracted into a separate table and synthesized for analysis. All International Classification of Diseases version 10 codes will be listed in tables and the codes that are used to define concussion, acquired traumatic brain injury, head injury, or head trauma will be identified. Discussion The identification of the optimal International Classification of Diseases version 10 codes to define this population in administrative data is crucial, as it has implications for policy, resource allocation, planning of healthcare services, and prevention strategies. It also allows for comparisons across countries and studies. This protocol is for a review that identifies the range and most common diagnoses used to conduct surveillance for traumatic brain injury in children and youth. This is an important first step in reaching an appropriate definition using International Classification of Diseases version 10 codes and can inform future work on reaching consensus on the codes to define traumatic brain injury for this vulnerable population. PMID:24219843

  13. Molecular classification of brain tumor biopsies using solid-state magic angle spinning proton magnetic resonance spectroscopy and robust classifiers.

    PubMed

    Andronesi, Ovidiu C; Blekas, Konstantinos D; Mintzopoulos, Dionyssios; Astrakas, Loukas; Black, Peter M; Tzika, A Aria

    2008-11-01

    Brain tumors are one of the leading causes of death in adults with cancer; however, molecular classification of these tumors with in vivo magnetic resonance spectroscopy (MRS) is limited because of the small number of metabolites detected. In vitro MRS provides highly informative biomarker profiles at higher fields, but also consumes the sample so that it is unavailable for subsequent analysis. In contrast, ex vivo high-resolution magic angle spinning (HRMAS) MRS conserves the sample but requires large samples and can pose technical challenges for producing accurate data, depending on the sample testing temperature. We developed a novel approach that combines a two-dimensional (2D), solid-state, HRMAS proton (1H) NMR method, TOBSY (total through-bond spectroscopy), which maximizes the advantages of HRMAS and a robust classification strategy. We used approximately 2 mg of tissue at -8 degrees C from each of 55 brain biopsies, and reliably detected 16 different biologically relevant molecular species. We compared two classification strategies, the support vector machine (SVM) classifier and a feed-forward neural network using the Levenberg-Marquardt back-propagation algorithm. We used the minimum redundancy/maximum relevance (MRMR) method as a powerful feature-selection scheme along with the SVM classifier. We suggest that molecular characterization of brain tumors based on highly informative 2D MRS should enable us to type and prognose even inoperable patients with high accuracy in vivo. PMID:18949365

  14. A systematic review of functional magnetic resonance imaging and diffusion tensor imaging modalities used in presurgical planning of brain tumour resection.

    PubMed

    Dimou, S; Battisti, R A; Hermens, D F; Lagopoulos, J

    2013-04-01

    Historically, brain tumour resection has relied upon standardised anatomical atlases and classical mapping techniques for successful resection. While these have provided adequate results in the past, the emergence of new technologies has heralded a wave of less invasive, patient-specific techniques for the mapping of brain function. Functional magnetic resonance imaging (fMRI) and, more recently, diffusion tensor imaging (DTI) are two such techniques. While fMRI is able to highlight localisation of function within the cortex, DTI represents the only technique able to elucidate white matter structures in vivo. Used in conjunction, both of these techniques provide important presurgical information for thorough preoperative planning, as well as intraoperatively via integration into frameless stereotactic neuronavigational systems. Together, these techniques show great promise for improved neurosurgical outcomes. While further research is required for more widespread clinical validity and acceptance, results from the literature provide a clear road map for future research and development to cement these techniques into the clinical setup of neurosurgical departments globally. PMID:23187966

  15. Matched signal detection on graphs: Theory and application to brain imaging data classification.

    PubMed

    Hu, Chenhui; Sepulcre, Jorge; Johnson, Keith A; Fakhri, Georges E; Lu, Yue M; Li, Quanzheng

    2016-01-15

    Motivated by recent progress in signal processing on graphs, we have developed a matched signal detection (MSD) theory for signals with intrinsic structures described by weighted graphs. First, we regard graph Laplacian eigenvalues as frequencies of graph-signals and assume that the signal is in a subspace spanned by the first few graph Laplacian eigenvectors associated with lower eigenvalues. The conventional matched subspace detector can be applied to this case. Furthermore, we study signals that may not merely live in a subspace. Concretely, we consider signals with bounded variation on graphs and more general signals that are randomly drawn from a prior distribution. For bounded variation signals, the test is a weighted energy detector. For the random signals, the test statistic is the difference of signal variations on associated graphs, if a degenerate Gaussian distribution specified by the graph Laplacian is adopted. We evaluate the effectiveness of the MSD on graphs both with simulated and real data sets. Specifically, we apply MSD to the brain imaging data classification problem of Alzheimer's disease (AD) based on two independent data sets: 1) positron emission tomography data with Pittsburgh compound-B tracer of 30 AD and 40 normal control (NC) subjects, and 2) resting-state functional magnetic resonance imaging (R-fMRI) data of 30 early mild cognitive impairment and 20 NC subjects. Our results demonstrate that the MSD approach is able to outperform the traditional methods and help detect AD at an early stage, probably due to the success of exploiting the manifold structure of the data. PMID:26481679

  16. Improving brain-computer interface classification using adaptive common spatial patterns.

    PubMed

    Song, Xiaomu; Yoon, Suk-Chung

    2015-06-01

    Common Spatial Patterns (CSP) is a widely used spatial filtering technique for electroencephalography (EEG)-based brain-computer interface (BCI). It is a two-class supervised technique that needs subject-specific training data. Due to EEG nonstationarity, EEG signal may exhibit significant intra- and inter-subject variation. As a result, spatial filters learned from a subject may not perform well for data acquired from the same subject at a different time or from other subjects performing the same task. Studies have been performed to improve CSP's performance by adding regularization terms into the training. Most of them require target subjects' training data with known class labels. In this work, an adaptive CSP (ACSP) method is proposed to analyze single trial EEG data from single and multiple subjects. The method does not estimate target data's class labels during the adaptive learning and updates spatial filters for both classes simultaneously. The proposed method was evaluated based on a comparison study with the classic CSP and several CSP-based adaptive methods using motor imagery EEG data from BCI competitions. Experimental results indicate that the proposed method can improve the classification performance as compared to the other methods. For circumstances where true class labels of target data are not instantly available, it was examined if adding classified target data to training data would improve the ACSP learning. Experimental results show that it would be better to exclude them from the training data. The proposed ACSP method can be performed in real-time and is potentially applicable to various EEG-based BCI applications. PMID:25909828

  17. Molecular classification of brain tumor biopsies using solid-state magic angle spinning proton magnetic resonance spectroscopy and robust classifiers

    PubMed Central

    Andronesi, Ovidiu C.; Blekas, Konstantinos D.; Mintzopoulos, Dionyssios; Astrakas, Loukas; Black, Peter M.; Tzika, A. Aria

    2008-01-01

    Brain tumors are one of the leading causes of death in adults with cancer; however, molecular classification of these tumors with in vivo magnetic resonance spectroscopy (MRS) is limited because of the small number of metabolites detected. In vitro MRS provides highly informative biomarker profiles at higher fields, but also consumes the sample so that it is unavailable for subsequent analysis. In contrast, ex vivo high-resolution magic angle spinning (HRMAS) MRS conserves the sample but requires large samples and can pose technical challenges for producing accurate data, depending on the sample testing temperature. We developed a novel approach that combines a two-dimensional (2D), solid-state, HRMAS proton (1H) NMR method, TOBSY (total through-bond spectroscopy), which maximizes the advantages of HRMAS and a robust classification strategy. We used 2 mg of tissue at -8°C from each of 55 brain biopsies, and reliably detected 16 different molecules. We compared two classification strategies, the support vector machine (SVM) classifier and a feed-forward neural network using the Levenberg-Marquardt back-propagation algorithm. We used the minimum redundancy/maximum relevance (MRMR) method as a powerful feature-selection scheme along with the SVM classifier. We also used the minimum redundancy/maximum relevance (MRMR) method as a powerful feature-selection scheme along with the SVM classifier. PMID:18949365

  18. Which method of posttraumatic stress disorder classification best predicts psychosocial function in children with traumatic brain injury?

    PubMed

    Iselin, Greg; Le Brocque, Robyne; Kenardy, Justin; Anderson, Vicki; McKinlay, Lynne

    2010-10-01

    Controversy surrounds the classification of posttraumatic stress disorder (PTSD), particularly in children and adolescents with traumatic brain injury (TBI). In these populations, it is difficult to differentiate TBI-related organic memory loss from dissociative amnesia. Several alternative PTSD classification algorithms have been proposed for use with children. This paper investigates DSM-IV-TR and alternative PTSD classification algorithms, including and excluding the dissociative amnesia item, in terms of their ability to predict psychosocial function following pediatric TBI. A sample of 184 children aged 6-14 years were recruited following emergency department presentation and/or hospital admission for TBI. PTSD was assessed via semi-structured clinical interview (CAPS-CA) with the child at 3 months post-injury. Psychosocial function was assessed using the parent report CHQ-PF50. Two alternative classification algorithms, the PTSD-AA and 2 of 3 algorithms, reached statistical significance. While the inclusion of the dissociative amnesia item increased prevalence rates across algorithms, it generally resulted in weaker associations with psychosocial function. The PTSD-AA algorithm appears to have the strongest association with psychosocial function following TBI in children and adolescents. Removing the dissociative amnesia item from the diagnostic algorithm generally results in improved validity. PMID:20541906

  19. Single-trial classification of multi-user P300-based Brain-Computer Interface using riemannian geometry.

    PubMed

    Korczowski, L; Congedo, M; Jutten, C

    2015-08-01

    The classification of electroencephalographic (EEG) data recorded from multiple users simultaneously is an important challenge in the field of Brain-Computer Interface (BCI). In this paper we compare different approaches for classification of single-trials Event-Related Potential (ERP) on two subjects playing a collaborative BCI game. The minimum distance to mean (MDM) classifier in a Riemannian framework is extended to use the diversity of the inter-subjects spatio-temporal statistics (MDM-hyper) or to merge multiple classifiers (MDM-multi). We show that both these classifiers outperform significantly the mean performance of the two users and analogous classifiers based on the step-wise linear discriminant analysis. More importantly, the MDM-multi outperforms the performance of the best player within the pair. PMID:26736621

  20. Radiological aspects of gamma knife radiosurgery for arteriovenous malformations and other non-tumoural disorders of the brain.

    PubMed

    Guo, W Y

    1993-01-01

    The aims of the thesis were to investigate stereotaxic procedures in radiosurgery for cerebral arteriovenous malformations (AVMs) and radiation effects of single session high-dose irradiation delivered by gamma knife on the human brain. Investigation of gamma knife radiosurgery in 1,464 patients constitutes the data base of this thesis. High quality stereotaxic angiography is the gold standard targeting imaging in radiosurgery for cerebral AVMs, particularly for small AVMs or residual AVMs after other treatments. For medium and large size AVMs, stereotaxic MR techniques can improve targeting precision and decrease irradiation volume as compared to stereotaxic angiography in selected cases provided that proper pulse sequences are used. Combined treatments, where embolization precedes radiosurgery, can improve amenability of the treatment for large AVMs. This is on condition that the partially embolized nidi are well delineated and the volume of the residual nidi has been decreased to a level where an optimum irradiation can be safely prescribed. Radiologically, adverse radiation effects (ARE) of gamma knife radiosurgery for cerebral AVMs are observed in 16% (131/816) of the patients. The ARE are observed as a focal low attenuation on CT or as a focal high signal on MR image without enhancement in 47% (61/131), and as a peripheral or homogeneous enhancing lesion in 48% (63/131). MR imaging is more sensitive than CT in detecting the ARE. 91% of the ARE are observed within 18 months after radiosurgery and 89% are seen to regress within 18 months. Clinically, symptomatic ARE are only observed in 6% (51/816) and only in half of them, i.e. 3%, are the symptoms permanent. The risk of ARE in radiosurgery for venous angiomas is higher as compared to AVMs. Other mechanisms have probably been employed. In gamma capsulotomy, the necrotic lesions and reaction volumes created by using multiple isocentres of 4 mm collimators are less predictable as compared to that by single isocentre. Volume effects and depreciation of the steep isodose gradient are hypothesised as the leading factors of the inconsistency. Based on the in vivo assessment of the radiation effects observed on the basically normal human brain it is concluded that irradiation volume is strongly related to the radiation effects and is one of the important considerations in decision making for radiosurgery. Volume of brain tissue exposed to irradiation could be minimised and precision of targeting could be maximised provided that a proper stereotaxic imaging is used.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:8517190

  1. Toward FRP-Based Brain-Machine Interfaces-Single-Trial Classification of Fixation-Related Potentials.

    PubMed

    Finke, Andrea; Essig, Kai; Marchioro, Giuseppe; Ritter, Helge

    2016-01-01

    The co-registration of eye tracking and electroencephalography provides a holistic measure of ongoing cognitive processes. Recently, fixation-related potentials have been introduced to quantify the neural activity in such bi-modal recordings. Fixation-related potentials are time-locked to fixation onsets, just like event-related potentials are locked to stimulus onsets. Compared to existing electroencephalography-based brain-machine interfaces that depend on visual stimuli, fixation-related potentials have the advantages that they can be used in free, unconstrained viewing conditions and can also be classified on a single-trial level. Thus, fixation-related potentials have the potential to allow for conceptually different brain-machine interfaces that directly interpret cortical activity related to the visual processing of specific objects. However, existing research has investigated fixation-related potentials only with very restricted and highly unnatural stimuli in simple search tasks while participant's body movements were restricted. We present a study where we relieved many of these restrictions while retaining some control by using a gaze-contingent visual search task. In our study, participants had to find a target object out of 12 complex and everyday objects presented on a screen while the electrical activity of the brain and eye movements were recorded simultaneously. Our results show that our proposed method for the classification of fixation-related potentials can clearly discriminate between fixations on relevant, non-relevant and background areas. Furthermore, we show that our classification approach generalizes not only to different test sets from the same participant, but also across participants. These results promise to open novel avenues for exploiting fixation-related potentials in electroencephalography-based brain-machine interfaces and thus providing a novel means for intuitive human-machine interaction. PMID:26812487

  2. Toward FRP-Based Brain-Machine Interfaces—Single-Trial Classification of Fixation-Related Potentials

    PubMed Central

    Finke, Andrea; Essig, Kai; Marchioro, Giuseppe; Ritter, Helge

    2016-01-01

    The co-registration of eye tracking and electroencephalography provides a holistic measure of ongoing cognitive processes. Recently, fixation-related potentials have been introduced to quantify the neural activity in such bi-modal recordings. Fixation-related potentials are time-locked to fixation onsets, just like event-related potentials are locked to stimulus onsets. Compared to existing electroencephalography-based brain-machine interfaces that depend on visual stimuli, fixation-related potentials have the advantages that they can be used in free, unconstrained viewing conditions and can also be classified on a single-trial level. Thus, fixation-related potentials have the potential to allow for conceptually different brain-machine interfaces that directly interpret cortical activity related to the visual processing of specific objects. However, existing research has investigated fixation-related potentials only with very restricted and highly unnatural stimuli in simple search tasks while participant’s body movements were restricted. We present a study where we relieved many of these restrictions while retaining some control by using a gaze-contingent visual search task. In our study, participants had to find a target object out of 12 complex and everyday objects presented on a screen while the electrical activity of the brain and eye movements were recorded simultaneously. Our results show that our proposed method for the classification of fixation-related potentials can clearly discriminate between fixations on relevant, non-relevant and background areas. Furthermore, we show that our classification approach generalizes not only to different test sets from the same participant, but also across participants. These results promise to open novel avenues for exploiting fixation-related potentials in electroencephalography-based brain-machine interfaces and thus providing a novel means for intuitive human-machine interaction. PMID:26812487

  3. Myoepithelial cells in canine mammary tumours.

    PubMed

    Sánchez-Céspedes, Raquel; Millán, Yolanda; Guil-Luna, Silvia; Reymundo, Carlos; Espinosa de Los Monteros, Antonio; Martín de Las Mulas, Juana

    2016-01-01

    Mammary tumours are the most common neoplasms of female dogs. Compared to mammary tumours of humans and cats, myoepithelial (ME) cell involvement is common in canine mammary tumours (CMT) of any subtype. Since ME cell involvement in CMT influences both histogenetic tumour classification and prognosis, correct identification of ME cells is important. This review describes immunohistochemical methods for identification of canine mammary ME cells used in vivo. In addition, phenotypic and genotypic methods to isolate ME cells for in vitro studies to analyse tumour-suppressor protein production and gene expression are discussed. The contribution of ME cells to both histogenetic classifications and the prognosis of CMT is compared with other species and the potential use of ME cells as a method to identify carcinoma in situ is discussed. PMID:26639832

  4. Description and classification of normal and pathological aging processes based on brain magnetic resonance imaging morphology measures.

    PubMed

    Perez-Gonzalez, Jorge Luis; Yanez-Suarez, Oscar; Bribiesca, Ernesto; Cosío, Fernando Arámbula; Jiménez, Juan Ramón; Medina-Bañuelos, Veronica

    2014-10-01

    We present a discrete compactness (DC) index, together with a classification scheme, based both on the size and shape features extracted from brain volumes, to determine different aging stages: healthy controls (HC), mild cognitive impairment (MCI), and Alzheimer's disease (AD). A set of 30 brain magnetic resonance imaging (MRI) volumes for each group was segmented and two indices were measured for several structures: three-dimensional DC and normalized volumes (NVs). The discrimination power of these indices was determined by means of the area under the curve (AUC) of the receiver operating characteristic, where the proposed compactness index showed an average AUC of 0.7 for HC versus MCI comparison, 0.9 for HC versus AD separation, and 0.75 for MCI versus AD groups. In all cases, this index outperformed the discrimination capability of the NV. Using selected features from the set of DC and NV measures, three support vector machines were optimized and validated for the pairwise separation of the three classes. Our analysis shows classification rates of up to 98.3% between HC and AD, 85% between HC and MCI, and 93.3% for MCI and AD separation. These results outperform those reported in the literature and demonstrate the viability of the proposed morphological indices to classify different aging stages. PMID:26158061

  5. Description and classification of normal and pathological aging processes based on brain magnetic resonance imaging morphology measures

    PubMed Central

    Perez-Gonzalez, Jorge Luis; Yanez-Suarez, Oscar; Bribiesca, Ernesto; Cosío, Fernando Arámbula; Jiménez, Juan Ramón; Medina-Bañuelos, Veronica

    2014-01-01

    Abstract. We present a discrete compactness (DC) index, together with a classification scheme, based both on the size and shape features extracted from brain volumes, to determine different aging stages: healthy controls (HC), mild cognitive impairment (MCI), and Alzheimer’s disease (AD). A set of 30 brain magnetic resonance imaging (MRI) volumes for each group was segmented and two indices were measured for several structures: three-dimensional DC and normalized volumes (NVs). The discrimination power of these indices was determined by means of the area under the curve (AUC) of the receiver operating characteristic, where the proposed compactness index showed an average AUC of 0.7 for HC versus MCI comparison, 0.9 for HC versus AD separation, and 0.75 for MCI versus AD groups. In all cases, this index outperformed the discrimination capability of the NV. Using selected features from the set of DC and NV measures, three support vector machines were optimized and validated for the pairwise separation of the three classes. Our analysis shows classification rates of up to 98.3% between HC and AD, 85% between HC and MCI, and 93.3% for MCI and AD separation. These results outperform those reported in the literature and demonstrate the viability of the proposed morphological indices to classify different aging stages. PMID:26158061

  6. kNN-based multi-spectral MRI brain tissue classification: manual training versus automated atlas-based training

    NASA Astrophysics Data System (ADS)

    Vrooman, Henri A.; Cocosco, Chris A.; Stokking, Rik; Ikram, M. Arfan; Vernooij, Meike W.; Breteler, Monique M.; Niessen, Wiro J.

    2006-03-01

    Conventional k-Nearest-Neighbor (kNN) classification, which has been successfully applied to classify brain tissue, requires laborious training on manually labeled subjects. In this work, the performance of kNN-based segmentation of gray matter (GM), white matter (WM) and cerebrospinal fluid (CSF) using manual training is compared with a new method, in which training is automated using an atlas. From 12 subjects, standard T2 and PD scans and a high-resolution, high-contrast scan (Siemens T1-weighted HASTE sequence with reverse contrast) were used as feature sets. For the conventional kNN method, manual segmentations were used for training, and classifications were evaluated in a leave-one-out study. The performance as a function of the number of samples per tissue, and k was studied. For fully automated training, scans were registered to a probabilistic brain atlas. Initial training samples were randomly selected per tissue based on a threshold on the tissue probability. These initials were processed to keep the most reliable samples. Performance of the method for varying the threshold on the tissue probability method was studied. By measuring the percentage overlap (SI), classification results of both methods were validated. For conventional kNN classification, varying the number of training samples did not result in significant differences, while increasing k gave significantly better results. In the method using automated training, there is an overestimation of GM at the expense of CSF at higher thresholds on the tissue probability maps. The difference between the conventional method (k=45) and the observers was not significantly larger than inter-observer variability for all tissue types. The automated method performed slightly worse and performed equal to the observers for WM, and less for CSF and GM. From these results it can be concluded that conventional kNN classification may replace manual segmentation, and that atlas-based kNN segmentation has strong potential for fully automated segmentation, without the need of laborious manual training.

  7. Gastroenteropancreatic neuroendocrine tumours.

    PubMed

    Modlin, Irvin M; Oberg, Kjell; Chung, Daniel C; Jensen, Robert T; de Herder, Wouter W; Thakker, Rajesh V; Caplin, Martyn; Delle Fave, Gianfranco; Kaltsas, Greg A; Krenning, Eric P; Moss, Steven F; Nilsson, Ola; Rindi, Guido; Salazar, Ramon; Ruszniewski, Philippe; Sundin, Anders

    2008-01-01

    Gastroenteropancreatic (GEP) neuroendocrine tumours (NETs) are fairly rare neoplasms that present many clinical challenges. They secrete peptides and neuroamines that cause distinct clinical syndromes, including carcinoid syndrome. However, many are clinically silent until late presentation with mass effects. Investigation and management should be highly individualised for a patient, taking into consideration the likely natural history of the tumour and general health of the patient. Management strategies include surgery for cure (which is achieved rarely) or for cytoreduction, radiological intervention (by chemoembolisation and radiofrequency ablation), chemotherapy, and somatostatin analogues to control symptoms that result from release of peptides and neuroamines. New biological agents and somatostatin-tagged radionuclides are under investigation. The complexity, heterogeneity, and rarity of GEP NETs have contributed to a paucity of relevant randomised trials and little or no survival increase over the past 30 years. To improve outcome from GEP NETs, a better understanding of their biology is needed, with emphasis on molecular genetics and disease modeling. More-reliable serum markers, better tumour localisation and identification of small lesions, and histological grading systems and classifications with prognostic application are needed. Comparison between treatments is currently very difficult. Progress is unlikely to occur without development of centers of excellence, with dedicated combined clinical teams to coordinate multicentre studies, maintain clinical and tissue databases, and refine molecularly targeted therapeutics. PMID:18177818

  8. Brain classification reveals the right cerebellum as the best biomarker of dyslexia

    PubMed Central

    Pernet, Cyril R; Poline, Jean Baptiste; Demonet, Jean François; Rousselet, Guillaume A

    2009-01-01

    Background Developmental dyslexia is a specific cognitive disorder in reading acquisition that has genetic and neurological origins. Despite histological evidence for brain differences in dyslexia, we recently demonstrated that in large cohort of subjects, no differences between control and dyslexic readers can be found at the macroscopic level (MRI voxel), because of large variances in brain local volumes. In the present study, we aimed at finding brain areas that most discriminate dyslexic from control normal readers despite the large variance across subjects. After segmenting brain grey matter, normalizing brain size and shape and modulating the voxels' content, normal readers' brains were used to build a 'typical' brain via bootstrapped confidence intervals. Each dyslexic reader's brain was then classified independently at each voxel as being within or outside the normal range. We used this simple strategy to build a brain map showing regional percentages of differences between groups. The significance of this map was then assessed using a randomization technique. Results The right cerebellar declive and the right lentiform nucleus were the two areas that significantly differed the most between groups with 100% of the dyslexic subjects (N = 38) falling outside of the control group (N = 39) 95% confidence interval boundaries. The clinical relevance of this result was assessed by inquiring cognitive brain-based differences among dyslexic brain subgroups in comparison to normal readers' performances. The strongest difference between dyslexic subgroups was observed between subjects with lower cerebellar declive (LCD) grey matter volumes than controls and subjects with higher cerebellar declive (HCD) grey matter volumes than controls. Dyslexic subjects with LCD volumes performed worse than subjects with HCD volumes in phonologically and lexicon related tasks. Furthermore, cerebellar and lentiform grey matter volumes interacted in dyslexic subjects, so that lower and higher lentiform grey matter volumes compared to controls differently modulated the phonological and lexical performances. Best performances (observed in controls) corresponded to an optimal value of grey matter and they dropped for higher or lower volumes. Conclusion These results provide evidence for the existence of various subtypes of dyslexia characterized by different brain phenotypes. In addition, behavioural analyses suggest that these brain phenotypes relate to different deficits of automatization of language-based processes such as grapheme/phoneme correspondence and/or rapid access to lexicon entries. PMID:19555471

  9. Partial volume effect modeling for segmentation and tissue classification of brain magnetic resonance images: A review

    PubMed Central

    Tohka, Jussi

    2014-01-01

    Quantitative analysis of magnetic resonance (MR) brain images are facilitated by the development of automated segmentation algorithms. A single image voxel may contain of several types of tissues due to the finite spatial resolution of the imaging device. This phenomenon, termed partial volume effect (PVE), complicates the segmentation process, and, due to the complexity of human brain anatomy, the PVE is an important factor for accurate brain structure quantification. Partial volume estimation refers to a generalized segmentation task where the amount of each tissue type within each voxel is solved. This review aims to provide a systematic, tutorial-like overview and categorization of methods for partial volume estimation in brain MRI. The review concentrates on the statistically based approaches for partial volume estimation and also explains differences to other, similar image segmentation approaches. PMID:25431640

  10. Automatic segmentation of brain MR images using an adaptive balloon snake model with fuzzy classification.

    PubMed

    Liu, Hung-Ting; Sheu, Tony W H; Chang, Herng-Hua

    2013-10-01

    Skull-stripping in magnetic resonance (MR) images is one of the most important preprocessing steps in medical image analysis. We propose a hybrid skull-stripping algorithm based on an adaptive balloon snake (ABS) model. The proposed framework consists of two phases: first, the fuzzy possibilistic c-means (FPCM) is used for pixel clustering, which provides a labeled image associated with a clean and clear brain boundary. At the second stage, a contour is initialized outside the brain surface based on the FPCM result and evolves under the guidance of an adaptive balloon snake model. The model is designed to drive the contour in the inward normal direction to capture the brain boundary. The entire volume is segmented from the center slice toward both ends slice by slice. Our ABS algorithm was applied to numerous brain MR image data sets and compared with several state-of-the-art methods. Four similarity metrics were used to evaluate the performance of the proposed technique. Experimental results indicated that our method produced accurate segmentation results with higher conformity scores. The effectiveness of the ABS algorithm makes it a promising and potential tool in a wide variety of skull-stripping applications and studies. PMID:23744446

  11. Outcome Classification of Preschool Children with Autism Spectrum Disorders Using Mri Brain Measures.

    ERIC Educational Resources Information Center

    Akshoomoff, Natacha; Lord, Catherine; Lincoln, Alan J.; Courchesne, Rachel Y.; Carper, Ruth A.; Townsend, Jeanne; Courchesne, Eric

    2004-01-01

    Objective: To test the hypothesis that a combination of magnetic resonance imaging (MRI) brain measures obtained during early childhood distinguish children with autism spectrum disorders (ASD) from typically developing children and is associated with functional outcome. Method: Quantitative MRI technology was used to measure gray and white matter…

  12. WAIS Digit Span-Based Indicators of Malingered Neurocognitive Dysfunction: Classification Accuracy in Traumatic Brain Injury

    ERIC Educational Resources Information Center

    Heinly, Matthew T.; Greve, Kevin W.; Bianchini, Kevin J.; Love, Jeffrey M.; Brennan, Adrianne

    2005-01-01

    The present study determined specificity and sensitivity to malingered neurocognitive dysfunction (MND) in traumatic brain injury (TBI) for several Wechsler Adult Intelligence Scale (WAIS) Digit Span scores. TBI patients (n = 344) were categorized into one of five groups: no incentive, incentive only, suspect, probable MND, and definite MND.…

  13. Outcome Classification of Preschool Children with Autism Spectrum Disorders Using Mri Brain Measures.

    ERIC Educational Resources Information Center

    Akshoomoff, Natacha; Lord, Catherine; Lincoln, Alan J.; Courchesne, Rachel Y.; Carper, Ruth A.; Townsend, Jeanne; Courchesne, Eric

    2004-01-01

    Objective: To test the hypothesis that a combination of magnetic resonance imaging (MRI) brain measures obtained during early childhood distinguish children with autism spectrum disorders (ASD) from typically developing children and is associated with functional outcome. Method: Quantitative MRI technology was used to measure gray and white matter…

  14. A composite malignant tumour of the elderly female breast

    PubMed Central

    Wayte, D. M.; Stewart, J. B.; McKenzie, C. G.

    1970-01-01

    A composite malignant tumour arising in the breast of an elderly woman is described. The cystic tumour containing areas of squamous metaplasia, bone formation, adenocarcinoma, and osteosarcoma was surrounded by the typical changes of mammary dysplasia (fibroadenosis). The classification and acceptance of such tumours is highly debatable. There is no one acceptable classification of breast sarcomas and hence the prognosis of such neoplasms, particularly those containing heterologous tissues, is poorly defined. Evidence is presented in support of such composite tumours as being definite entities which arise from the closely associated epithelial and mesenchymal components of the breast simultaneously. Images PMID:4320045

  15. Future use of mitocans against tumour-initiating cells?

    PubMed

    Morrison, Brian J; Andera, Ladislav; Reynolds, Brent A; Ralph, Stephen J; Neuzil, Jiri

    2009-01-01

    Tumour heterogeneity has several important consequences including: (i) making their classification by morphological and genetic analysis more difficult because of the diversity within single tumours and the common majority of cells as the bulk of a tumour will dominate this classification whether or not these cells are critical for diagnosis or treatment, (ii) treatments may fail to eradicate tumours simply by failing to eliminate one of the cell subtypes within the tumour and (iii) differing abilities of the cell subtypes for dissemination and metastasis. Recently, a rare subpopulation of cells within tumours has been described with the ability to initiate and sustain tumour growth, to resist traditional therapies and to allow for secondary tumour dissemination. These cells are termed tumour-initiating cells (TICs). Understanding tumour heterogeneity will be critical for advancing treatments for cancer that target TIC subpopulations of cells in a tumour able to resist traditional treatments and eliminate them before metastatic disease occurs. It follows that the TICs will be the most important cellular components in the tumour target. Therefore, knowledge of the molecular mechanism(s) of resistance of TICs to treatment and overcoming this problem will be essential in order to develop effective drug strategies for cancer therapy. PMID:19123176

  16. Tumours of the upper alimentary tract

    PubMed Central

    Head, K. W.

    1976-01-01

    Tumours of the oropharynx of domestic animals are common in most parts of the world, but squamous cell carcinoma of the upper alimentary tract shows differences in prevalence in different geographical areas and occurs at different sites in the various species. Oral tumours of the melanogenic system are more common in dogs than in man. The following main histological categories, which broadly correspond to those used in the classification of tumours of man, are described: papilloma; squamous cell carcinoma; salivary gland tumours; malignant melanoma; tumours of soft (mesenchymal) tissues; tumours of the facial bones; tumours of haematopoietic and related tissues; and odontogenic tumours and jaw cysts. Papilloma, squamous cell carcinoma, malignant melanoma, fibroma, and fibrosarcoma account for about 80% of the tumours that occur in the upper alimentary tract of domestic animals. ImagesFig. 6Fig. 7Fig. 8Fig. 9Fig. 34Fig. 35Fig. 36Fig. 37Fig. 2Fig. 3Fig. 4Fig. 5Fig. 22Fig. 23Fig. 24Fig. 25Fig. 26Fig. 27Fig. 28Fig. 29Fig. 14Fig. 15Fig. 16Fig. 17Fig. 30Fig. 31Fig. 32Fig. 33Fig. 18Fig. 19Fig. 20Fig. 21Fig. 10Fig. 11Fig. 12Fig. 13Fig. 1 PMID:1086147

  17. Brain tissue classification based on DTI using an improved fuzzy C-means algorithm with spatial constraints.

    PubMed

    Wen, Ying; He, Lianghua; von Deneen, Karen M; Lu, Yue

    2013-11-01

    We present an effective method for brain tissue classification based on diffusion tensor imaging (DTI) data. The method accounts for two main DTI segmentation obstacles: random noise and magnetic field inhomogeneities. In the proposed method, DTI parametric maps were used to resolve intensity inhomogeneities of brain tissue segmentation because they could provide complementary information for tissues and define accurate tissue maps. An improved fuzzy c-means with spatial constraints proposal was used to enhance the noise and artifact robustness of DTI segmentation. Fuzzy c-means clustering with spatial constraints (FCM_S) could effectively segment images corrupted by noise, outliers, and other imaging artifacts. Its effectiveness contributes not only to the introduction of fuzziness for belongingness of each pixel but also to the exploitation of spatial contextual information. We proposed an improved FCM_S applied on DTI parametric maps, which explores the mean and covariance of the feature spatial information for automated segmentation of DTI. The experiments on synthetic images and real-world datasets showed that our proposed algorithms, especially with new spatial constraints, were more effective. PMID:23891435

  18. Characterization of a Raman spectroscopy probe system for intraoperative brain tissue classification.

    PubMed

    Desroches, Joannie; Jermyn, Michael; Mok, Kelvin; Lemieux-Leduc, Cédric; Mercier, Jeanne; St-Arnaud, Karl; Urmey, Kirk; Guiot, Marie-Christine; Marple, Eric; Petrecca, Kevin; Leblond, Frédéric

    2015-07-01

    A detailed characterization study is presented of a Raman spectroscopy system designed to maximize the volume of resected cancer tissue in glioma surgery based on in vivo molecular tissue characterization. It consists of a hand-held probe system measuring spectrally resolved inelastically scattered light interacting with tissue, designed and optimized for in vivo measurements. Factors such as linearity of the signal with integration time and laser power, and their impact on signal to noise ratio, are studied leading to optimal data acquisition parameters. The impact of ambient light sources in the operating room is assessed and recommendations made for optimal operating conditions. In vivo Raman spectra of normal brain, cancer and necrotic tissue were measured in 10 patients, demonstrating that real-time inelastic scattering measurements can distinguish necrosis from vital tissue (including tumor and normal brain tissue) with an accuracy of 87%, a sensitivity of 84% and a specificity of 89%. PMID:26203368

  19. Characterization of a Raman spectroscopy probe system for intraoperative brain tissue classification

    PubMed Central

    Desroches, Joannie; Jermyn, Michael; Mok, Kelvin; Lemieux-Leduc, Cédric; Mercier, Jeanne; St-Arnaud, Karl; Urmey, Kirk; Guiot, Marie-Christine; Marple, Eric; Petrecca, Kevin; Leblond, Frédéric

    2015-01-01

    A detailed characterization study is presented of a Raman spectroscopy system designed to maximize the volume of resected cancer tissue in glioma surgery based on in vivo molecular tissue characterization. It consists of a hand-held probe system measuring spectrally resolved inelastically scattered light interacting with tissue, designed and optimized for in vivo measurements. Factors such as linearity of the signal with integration time and laser power, and their impact on signal to noise ratio, are studied leading to optimal data acquisition parameters. The impact of ambient light sources in the operating room is assessed and recommendations made for optimal operating conditions. In vivo Raman spectra of normal brain, cancer and necrotic tissue were measured in 10 patients, demonstrating that real-time inelastic scattering measurements can distinguish necrosis from vital tissue (including tumor and normal brain tissue) with an accuracy of 87%, a sensitivity of 84% and a specificity of 89%. PMID:26203368

  20. Brain

    MedlinePLUS

    ... will return after updating. Resources Archived Modules Updates Brain Cerebrum The cerebrum is the part of the ... the outside of the brain and spinal cord. Brain Stem The brain stem is the part of ...

  1. Brain Tumor Classification Using AFM in Combination with Data Mining Techniques

    PubMed Central

    Huml, Marlene; Silye, René; Zauner, Gerald

    2013-01-01

    Although classification of astrocytic tumors is standardized by the WHO grading system, which is mainly based on microscopy-derived, histomorphological features, there is great interobserver variability. The main causes are thought to be the complexity of morphological details varying from tumor to tumor and from patient to patient, variations in the technical histopathological procedures like staining protocols, and finally the individual experience of the diagnosing pathologist. Thus, to raise astrocytoma grading to a more objective standard, this paper proposes a methodology based on atomic force microscopy (AFM) derived images made from histopathological samples in combination with data mining techniques. By comparing AFM images with corresponding light microscopy images of the same area, the progressive formation of cavities due to cell necrosis was identified as a typical morphological marker for a computer-assisted analysis. Using genetic programming as a tool for feature analysis, a best model was created that achieved 94.74% classification accuracy in distinguishing grade II tumors from grade IV ones. While utilizing modern image analysis techniques, AFM may become an important tool in astrocytic tumor diagnosis. By this way patients suffering from grade II tumors are identified unambiguously, having a less risk for malignant transformation. They would benefit from early adjuvant therapies. PMID:24062997

  2. Exceeding chance level by chance: The caveat of theoretical chance levels in brain signal classification and statistical assessment of decoding accuracy.

    PubMed

    Combrisson, Etienne; Jerbi, Karim

    2015-07-30

    Machine learning techniques are increasingly used in neuroscience to classify brain signals. Decoding performance is reflected by how much the classification results depart from the rate achieved by purely random classification. In a 2-class or 4-class classification problem, the chance levels are thus 50% or 25% respectively. However, such thresholds hold for an infinite number of data samples but not for small data sets. While this limitation is widely recognized in the machine learning field, it is unfortunately sometimes still overlooked or ignored in the emerging field of brain signal classification. Incidentally, this field is often faced with the difficulty of low sample size. In this study we demonstrate how applying signal classification to Gaussian random signals can yield decoding accuracies of up to 70% or higher in two-class decoding with small sample sets. Most importantly, we provide a thorough quantification of the severity and the parameters affecting this limitation using simulations in which we manipulate sample size, class number, cross-validation parameters (k-fold, leave-one-out and repetition number) and classifier type (Linear-Discriminant Analysis, Naïve Bayesian and Support Vector Machine). In addition to raising a red flag of caution, we illustrate the use of analytical and empirical solutions (binomial formula and permutation tests) that tackle the problem by providing statistical significance levels (p-values) for the decoding accuracy, taking sample size into account. Finally, we illustrate the relevance of our simulations and statistical tests on real brain data by assessing noise-level classifications in Magnetoencephalography (MEG) and intracranial EEG (iEEG) baseline recordings. PMID:25596422

  3. A discriminative model-constrained EM approach to 3D MRI brain tissue classification and intensity non-uniformity correction

    NASA Astrophysics Data System (ADS)

    Wels, Michael; Zheng, Yefeng; Huber, Martin; Hornegger, Joachim; Comaniciu, Dorin

    2011-06-01

    We describe a fully automated method for tissue classification, which is the segmentation into cerebral gray matter (GM), cerebral white matter (WM), and cerebral spinal fluid (CSF), and intensity non-uniformity (INU) correction in brain magnetic resonance imaging (MRI) volumes. It combines supervised MRI modality-specific discriminative modeling and unsupervised statistical expectation maximization (EM) segmentation into an integrated Bayesian framework. While both the parametric observation models and the non-parametrically modeled INUs are estimated via EM during segmentation itself, a Markov random field (MRF) prior model regularizes segmentation and parameter estimation. Firstly, the regularization takes into account knowledge about spatial and appearance-related homogeneity of segments in terms of pairwise clique potentials of adjacent voxels. Secondly and more importantly, patient-specific knowledge about the global spatial distribution of brain tissue is incorporated into the segmentation process via unary clique potentials. They are based on a strong discriminative model provided by a probabilistic boosting tree (PBT) for classifying image voxels. It relies on the surrounding context and alignment-based features derived from a probabilistic anatomical atlas. The context considered is encoded by 3D Haar-like features of reduced INU sensitivity. Alignment is carried out fully automatically by means of an affine registration algorithm minimizing cross-correlation. Both types of features do not immediately use the observed intensities provided by the MRI modality but instead rely on specifically transformed features, which are less sensitive to MRI artifacts. Detailed quantitative evaluations on standard phantom scans and standard real-world data show the accuracy and robustness of the proposed method. They also demonstrate relative superiority in comparison to other state-of-the-art approaches to this kind of computational task: our method achieves average Dice coefficients of 0.93 ± 0.03 (WM) and 0.90 ± 0.05 (GM) on simulated mono-spectral and 0.94 ± 0.02 (WM) and 0.92 ± 0.04 (GM) on simulated multi-spectral data from the BrainWeb repository. The scores are 0.81 ± 0.09 (WM) and 0.82 ± 0.06 (GM) and 0.87 ± 0.05 (WM) and 0.83 ± 0.12 (GM) for the two collections of real-world data sets—consisting of 20 and 18 volumes, respectively—provided by the Internet Brain Segmentation Repository.

  4. Mesenchymal tumours of the mediastinum-part I.

    PubMed

    den Bakker, Michael A; Marx, Alexander; Mukai, Kiyoshi; Ströbel, Philipp

    2015-11-01

    The mediastinum is an anatomically defined space in which organs and major blood vessels reside with surrounding soft tissue elements. The thymus is an important organ in the mediastinum, and many of the masses encountered in the mediastinum are related to this organ. Most neoplasms diagnosed in the mediastinum are epithelial tumours (thymomas and thymic carcinomas), lymphomas or germ cell tumours. In contrast, soft tissue tumours of the mediastinum are rare. In 1963, Pachter and Lattes systematically reviewed soft tissue pathology of the mediastinum, covering the hitherto described [2, 226, 227] In this review, based on the 2013 WHO classification of soft tissue tumours and the 2015 WHO classification of tumours of the lung, pleura, thymus and heart, we provide an updated overview of mesenchymal tumours that may be encountered in the mediastinum. PMID:26358059

  5. Automated classification of brain tumor type in whole-slide digital pathology images using local representative tiles.

    PubMed

    Barker, Jocelyn; Hoogi, Assaf; Depeursinge, Adrien; Rubin, Daniel L

    2016-05-01

    Computerized analysis of digital pathology images offers the potential of improving clinical care (e.g. automated diagnosis) and catalyzing research (e.g. discovering disease subtypes). There are two key challenges thwarting computerized analysis of digital pathology images: first, whole slide pathology images are massive, making computerized analysis inefficient, and second, diverse tissue regions in whole slide images that are not directly relevant to the disease may mislead computerized diagnosis algorithms. We propose a method to overcome both of these challenges that utilizes a coarse-to-fine analysis of the localized characteristics in pathology images. An initial surveying stage analyzes the diversity of coarse regions in the whole slide image. This includes extraction of spatially localized features of shape, color and texture from tiled regions covering the slide. Dimensionality reduction of the features assesses the image diversity in the tiled regions and clustering creates representative groups. A second stage provides a detailed analysis of a single representative tile from each group. An Elastic Net classifier produces a diagnostic decision value for each representative tile. A weighted voting scheme aggregates the decision values from these tiles to obtain a diagnosis at the whole slide level. We evaluated our method by automatically classifying 302 brain cancer cases into two possible diagnoses (glioblastoma multiforme (N = 182) versus lower grade glioma (N = 120)) with an accuracy of 93.1 % (p < 0.001). We also evaluated our method in the dataset provided for the 2014 MICCAI Pathology Classification Challenge, in which our method, trained and tested using 5-fold cross validation, produced a classification accuracy of 100% (p < 0.001). Our method showed high stability and robustness to parameter variation, with accuracy varying between 95.5% and 100% when evaluated for a wide range of parameters. Our approach may be useful to automatically differentiate between the two cancer subtypes. PMID:26854941

  6. Etiology-based classification of brain white matter hyperintensity on magnetic resonance imaging

    PubMed Central

    Leite, Mariana; Rittner, Letícia; Appenzeller, Simone; Ruocco, Heloísa Helena; Lotufo, Roberto

    2015-01-01

    Abstract. Brain white matter lesions found upon magnetic resonance imaging are often observed in psychiatric or neurological patients. Individuals with these lesions present a more significant cognitive impairment when compared with individuals without them. We propose a computerized method to distinguish tissue containing white matter lesions of different etiologies (e.g., demyelinating or ischemic) using texture-based classifiers. Texture attributes were extracted from manually selected regions of interest and used to train and test supervised classifiers. Experiments were conducted to evaluate texture attribute discrimination and classifiers’ performances. The most discriminating texture attributes were obtained from the gray-level histogram and from the co-occurrence matrix. The best classifier was the support vector machine, which achieved an accuracy of 87.9% in distinguishing lesions with different etiologies and an accuracy of 99.29% in distinguishing normal white matter from white matter lesions. PMID:26158080

  7. Distributed effects of methylphenidate on the network structure of the resting brain: a connectomic pattern classification analysis

    PubMed Central

    Sripada, Chandra Sekhar; Kessler, Daniel; Welsh, Robert; Angstadt, Michael; Liberzon, Israel; Phan, K. Luan; Scott, Clayton

    2013-01-01

    Methylphenidate is a psychostimulant medication that produces improvements in functions associated with multiple neurocognitive systems. To investigate the potentially distributed effects of methylphenidate on the brain’s intrinsic network architecture, we coupled resting state imaging with multivariate pattern classification. In a within-subject, double-blind, placebo-controlled, randomized, counterbalanced, cross-over design, 32 healthy human volunteers received either methylphenidate or placebo prior to two fMRI resting state scans separated by approximately one week. Resting state connectomes were generated by placing regions of interest at regular intervals throughout the brain, and these connectomes were submitted for support vector machine analysis. We found that methylphenidate produces a distributed, reliably detected, multivariate neural signature. Methylphenidate effects were evident across multiple resting state networks, especially visual, somatomotor, and default networks. Methylphenidate reduced coupling within visual and somatomotor networks. In addition, default network exhibited decoupling with several task positive networks, consistent with methylphenidate modulation of the competitive relationship between these networks. These results suggest that connectivity changes within and between large-scale networks is potentially involved in the mechanisms by which methylphenidate improves attention functioning. PMID:23684862

  8. Observed versus estimated IQ as an index of malingering in traumatic brain injury: classification accuracy in known groups.

    PubMed

    Greve, Kevin W; Lotz, Kenni L; Bianchini, Kevin J

    2008-01-01

    This study examined the classification accuracy of observed WAIS-III VIQ, PIQ, and FSIQ minus Barona-estimate differential scores in the detection of Malingered Neurocognitive Dysfunction (MND) in Traumatic Brain Injury (TBI) using a known-groups design. Two hundred eleven TBI patients were assigned to one of three groups: Not-MND (n = 87), Indeterminate (n = 68), and MND (n = 56). A General Clinical Sample of 93 no-incentive patients (e.g., CVA, memory disorder) was also included to better study specificity. The VIQ differential accurately differentiated MND from Not-MND TBI patients regardless of injury severity. The PIQ differential was only accurate in mild TBI and did not add incremental validity to the VIQ differential. This study indicates that VIQ declines of greater than 24 points are rare except in very severe TBI. Particularly in mild TBI, such differentials likely indicate intentional suppression of WAIS-III performance consistent with MND. Clinical application is discussed. PMID:18726736

  9. Classification of hemodynamic responses associated with force and speed imagery for a brain-computer interface.

    PubMed

    Yin, Xuxian; Xu, Baolei; Jiang, Changhao; Fu, Yunfa; Wang, Zhidong; Li, Hongyi; Shi, Gang

    2015-05-01

    Functional near-infrared spectroscopy (fNIRS) is an emerging optical technique, which can assess brain activities associated with tasks. In this study, six participants were asked to perform three imageries of hand clenching associated with force and speed, respectively. Joint mutual information (JMI) criterion was used to extract the optimal features of hemodynamic responses. And extreme learning machine (ELM) was employed to be the classifier. ELM solved the major bottleneck of feedforward neural networks in learning speed, this classifier was easily implemented and less sensitive to specified parameters. The 2-class fNIRS-BCI system was firstly built with an average accuracy of 76.7%, when all force and speed tasks were categorized as one class, respectively. The multi-class systems based on different levels of force and speed attempted to be investigated, the accuracies were moderate. This study provided a novel paradigm for establishing fNIRS-BCI system, and provided a possibility to produce more degrees of freedom in BCI system. PMID:25732084

  10. Comparing implementations of magnetic-resonance-guided fluorescence molecular tomography for diagnostic classification of brain tumors

    NASA Astrophysics Data System (ADS)

    Davis, Scott C.; Samkoe, Kimberley S.; O'Hara, Julia A.; Gibbs-Strauss, Summer L.; Paulsen, Keith D.; Pogue, Brian W.

    2010-09-01

    Fluorescence molecular tomography (FMT) systems coupled to conventional imaging modalities such as magnetic resonance imaging (MRI) and computed tomography provide unique opportunities to combine data sets and improve image quality and content. Yet, the ideal approach to combine these complementary data is still not obvious. This preclinical study compares several methods for incorporating MRI spatial prior information into FMT imaging algorithms in the context of in vivo tissue diagnosis. Populations of mice inoculated with brain tumors that expressed either high or low levels of epidermal growth factor receptor (EGFR) were imaged using an EGF-bound near-infrared dye and a spectrometer-based MRI-FMT scanner. All data were spectrally unmixed to extract the dye fluorescence from the tissue autofluorescence. Methods to combine the two data sets were compared using student's t-tests and receiver operating characteristic analysis. Bulk fluorescence measurements that made up the optical imaging data set were also considered in the comparison. While most techniques were able to distinguish EGFR(+) tumors from EGFR(-) tumors and control animals, with area-under-the-curve values=1, only a handful were able to distinguish EGFR(-) tumors from controls. Bulk fluorescence spectroscopy techniques performed as well as most imaging techniques, suggesting that complex imaging algorithms may be unnecessary to diagnose EGFR status in these tissue volumes.

  11. Clustering-initiated factor analysis application for tissue classification in dynamic brain positron emission tomography.

    PubMed

    Boutchko, Rostyslav; Mitra, Debasis; Baker, Suzanne L; Jagust, William J; Gullberg, Grant T

    2015-07-01

    The goal is to quantify the fraction of tissues that exhibit specific tracer binding in dynamic brain positron emission tomography (PET). It is achieved using a new method of dynamic image processing: clustering-initiated factor analysis (CIFA). Standard processing of such data relies on region of interest analysis and approximate models of the tracer kinetics and of tissue properties, which can degrade accuracy and reproducibility of the analysis. Clustering-initiated factor analysis allows accurate determination of the time-activity curves and spatial distributions for tissues that exhibit significant radiotracer concentration at any stage of the emission scan, including the arterial input function. We used this approach in the analysis of PET images obtained using (11)C-Pittsburgh Compound B in which specific binding reflects the presence of ?-amyloid. The fraction of the specific binding tissues determined using our approach correlated with that computed using the Logan graphical analysis. We believe that CIFA can be an accurate and convenient tool for measuring specific binding tissue concentration and for analyzing tracer kinetics from dynamic images for a variety of PET tracers. As an illustration, we show that four-factor CIFA allows extraction of two blood curves and the corresponding distributions of arterial and venous blood from PET images even with a coarse temporal resolution. PMID:25899294

  12. Mathematical Modelling of a Brain Tumour Initiation and Early Development: A Coupled Model of Glioblastoma Growth, Pre-Existing Vessel Co-Option, Angiogenesis and Blood Perfusion.

    PubMed

    Cai, Yan; Wu, Jie; Li, Zhiyong; Long, Quan

    2016-01-01

    We propose a coupled mathematical modelling system to investigate glioblastoma growth in response to dynamic changes in chemical and haemodynamic microenvironments caused by pre-existing vessel co-option, remodelling, collapse and angiogenesis. A typical tree-like architecture network with different orders for vessel diameter is designed to model pre-existing vasculature in host tissue. The chemical substances including oxygen, vascular endothelial growth factor, extra-cellular matrix and matrix degradation enzymes are calculated based on the haemodynamic environment which is obtained by coupled modelling of intravascular blood flow with interstitial fluid flow. The haemodynamic changes, including vessel diameter and permeability, are introduced to reflect a series of pathological characteristics of abnormal tumour vessels including vessel dilation, leakage, angiogenesis, regression and collapse. Migrating cells are included as a new phenotype to describe the migration behaviour of malignant tumour cells. The simulation focuses on the avascular phase of tumour development and stops at an early phase of angiogenesis. The model is able to demonstrate the main features of glioblastoma growth in this phase such as the formation of pseudopalisades, cell migration along the host vessels, the pre-existing vasculature co-option, angiogenesis and remodelling. The model also enables us to examine the influence of initial conditions and local environment on the early phase of glioblastoma growth. PMID:26934465

  13. Mathematical Modelling of a Brain Tumour Initiation and Early Development: A Coupled Model of Glioblastoma Growth, Pre-Existing Vessel Co-Option, Angiogenesis and Blood Perfusion

    PubMed Central

    Cai, Yan; Wu, Jie; Li, Zhiyong; Long, Quan

    2016-01-01

    We propose a coupled mathematical modelling system to investigate glioblastoma growth in response to dynamic changes in chemical and haemodynamic microenvironments caused by pre-existing vessel co-option, remodelling, collapse and angiogenesis. A typical tree-like architecture network with different orders for vessel diameter is designed to model pre-existing vasculature in host tissue. The chemical substances including oxygen, vascular endothelial growth factor, extra-cellular matrix and matrix degradation enzymes are calculated based on the haemodynamic environment which is obtained by coupled modelling of intravascular blood flow with interstitial fluid flow. The haemodynamic changes, including vessel diameter and permeability, are introduced to reflect a series of pathological characteristics of abnormal tumour vessels including vessel dilation, leakage, angiogenesis, regression and collapse. Migrating cells are included as a new phenotype to describe the migration behaviour of malignant tumour cells. The simulation focuses on the avascular phase of tumour development and stops at an early phase of angiogenesis. The model is able to demonstrate the main features of glioblastoma growth in this phase such as the formation of pseudopalisades, cell migration along the host vessels, the pre-existing vasculature co-option, angiogenesis and remodelling. The model also enables us to examine the influence of initial conditions and local environment on the early phase of glioblastoma growth. PMID:26934465

  14. Gender, Race, and Survival: A Study in Non-Small-Cell Lung Cancer Brain Metastases Patients Utilizing the Radiation Therapy Oncology Group Recursive Partitioning Analysis Classification

    SciTech Connect

    Videtic, Gregory M.M.; Reddy, Chandana A.; Chao, Samuel T.; Rice, Thomas W.; Adelstein, David J.; Barnett, Gene H.; Mekhail, Tarek M.; Vogelbaum, Michael A.; Suh, John H.

    2009-11-15

    Purpose: To explore whether gender and race influence survival in non-small-cell lung cancer (NSCLC) in patients with brain metastases, using our large single-institution brain tumor database and the Radiation Therapy Oncology Group recursive partitioning analysis (RPA) brain metastases classification. Methods and materials: A retrospective review of a single-institution brain metastasis database for the interval January 1982 to September 2004 yielded 835 NSCLC patients with brain metastases for analysis. Patient subsets based on combinations of gender, race, and RPA class were then analyzed for survival differences. Results: Median follow-up was 5.4 months (range, 0-122.9 months). There were 485 male patients (M) (58.4%) and 346 female patients (F) (41.6%). Of the 828 evaluable patients (99%), 143 (17%) were black/African American (B) and 685 (83%) were white/Caucasian (W). Median survival time (MST) from time of brain metastasis diagnosis for all patients was 5.8 months. Median survival time by gender (F vs. M) and race (W vs. B) was 6.3 months vs. 5.5 months (p = 0.013) and 6.0 months vs. 5.2 months (p = 0.08), respectively. For patients stratified by RPA class, gender, and race, MST significantly favored BFs over BMs in Class II: 11.2 months vs. 4.6 months (p = 0.021). On multivariable analysis, significant variables were gender (p = 0.041, relative risk [RR] 0.83) and RPA class (p < 0.0001, RR 0.28 for I vs. III; p < 0.0001, RR 0.51 for II vs. III) but not race. Conclusions: Gender significantly influences NSCLC brain metastasis survival. Race trended to significance in overall survival but was not significant on multivariable analysis. Multivariable analysis identified gender and RPA classification as significant variables with respect to survival.

  15. Raman and FTIR microspectroscopy for detection of brain metastasis

    NASA Astrophysics Data System (ADS)

    Bergner, Norbert; Romeike, Bernd F. M.; Reichart, Rupert; Kalff, Rolf; Krafft, Christoph; Popp, Jürgen

    2011-07-01

    Vibrational spectroscopic imaging methods are novel tools to visualise chemical component in tissue without staining. Fourier transform infrared (FTIR) imaging is more frequently applied than Raman imaging so far. FTIR images recorded with a FPA detector have been demonstrated to identify the primary tumours of brain metastases. However, the strong absorption of water makes it difficult to transfer the results to non-dried tissues. Raman spectroscopy with near infrared excitation can be used instead and allows collecting the chemical fingerprint of native specimens. Therefore, Raman spectroscopy is a promising tool for tumour diagnosis in neurosurgery. Scope of the study is to compare FTIR and Raman images to visualize the tumour border and identify spectral features for classification. Brain metastases were obtained from patients undergoing surgery at the university hospital. Brain tissue sections were shock frozen, cryosectioned, dried and the same areas were imaged with both spectroscopic method. To visualise the chemical components, multivariate statistical algorithms were applied for data analysis. Furthermore classification models were trained using supervised algorithms to predict the primary tumor of brain metastases. Principal component regression (PCR) was used for prediction based on FTIR images. Support vector machines (SVM) were used for prediction based on Raman images. The principles are shown for two specimens. In the future, the study will be extended to larger data sets.

  16. Randomized pilot study and qualitative evaluation of a clinical decision support system for brain tumour diagnosis based on SV ¹H MRS: evaluation as an additional information procedure for novice radiologists.

    PubMed

    Sáez, Carlos; Martí-Bonmatí, Luis; Alberich-Bayarri, Angel; Robles, Montserrat; García-Gómez, Juan M

    2014-02-01

    The results of a randomized pilot study and qualitative evaluation of the clinical decision support system Curiam BT are reported. We evaluated the system's feasibility and potential value as a radiological information procedure complementary to magnetic resonance (MR) imaging to assist novice radiologists in diagnosing brain tumours using MR spectroscopy (1.5 and 3.0T). Fifty-five cases were analysed at three hospitals according to four non-exclusive diagnostic questions. Our results show that Curiam BT improved the diagnostic accuracy in all the four questions. Additionally, we discuss the findings of the users' feedback about the system, and the further work to optimize it for real environments and to conduct a large clinical trial. PMID:24480160

  17. New frontiers for astrocytic tumours.

    PubMed

    Nano, Rosanna; Lascialfari, Alessandro; Corti, Maurizio; Paolini, Alessandro; Pasi, Francesca; Corbella, Franco; DI Liberto, Riccardo

    2012-07-01

    Glioblastoma multiforme, the most common type of primary brain tumour, remains an unsolved clinical problem. A great deal of work has been done in an effort to understand the biology and genetics of glioblastoma multiforme, but clinically effective treatments remain elusive. It is well known that malignant gliomas develop resistance to chemo- and radiotherapy. In this review we evaluated the literature data regarding therapeutic progress for the treatment of astrocytic tumours, focusing our attention on new frontiers for glioblastoma. The research studies performed in in vitro and in vivo models show that the application of hyperthermia using magnetic nanoparticles is safe and could be a promising tool in the treatment of glioblastoma patients. Our efforts are focused towards new fields of research, for example nanomedicine and the study of the uptake and cytotoxic effects of magnetic nanoparticles. The improvement of the quality of life of patients, by increasing their survival rate is the best result to be pursued, since these tumours are considered as ineradicable. PMID:22753735

  18. [Paediatric malignant liver tumours].

    PubMed

    Brugières, Laurence; Branchereau, Sophie; Laithier, Véronique

    2012-02-01

    Tumours and pseudotumours of the liver are a heterogeneous group of neoplasm including 60% of malignant tumours. Malignant liver tumours account for less than 2% of the lesions in children and vary considerably in incidence throughout the paediatric age range, with hepatoblastoma, rhabdoid tumour of the liver, hemangioendothelioma, biliary tract rhabdomysosarcoma and mesenchymal hamartoma in the first two years of life and hepatocellular carcinoma, focal nodular hyperplasia, and undifferentiated sarcoma in older children and adolescents. Treatment of malignant epithelial tumours is based on the surgical resection of the tumour associated with pre- and postoperative chemotherapy including cisplatinum. Modalities of the treatment are adapted to risk factors. Survival rates at three years are over 80% for localised hepatoblastoma whereas they are less than 30% in hepatocellular carcinomas. The role of targeted therapies still has to be defined. PMID:22266074

  19. Tumours of the pancreas.

    PubMed

    Kircher, C H; Nielsen, S W

    1976-01-01

    Tumours of the pancreas occur most commonly in dogs and cats and only rarely in other domestic species. The incidence of neoplasms, both exocrine and endocrine, increases with age. Exocrine adenocarcinomas are the most common malignant tumours and have three fairly distinct morphological patterns: small tubular, large tubular, and acinar cell (rare). They readily metastasize, usually before clinical signs are apparent. A "starry sky" pattern with clear histiocytes scattered among tumour cells is a regular feature of poorly differentiated areas of small tubular adenocarcinomas and undifferentiated carcinomas. Islet cell tumours occur in a significant number only in dogs. Metastases are found in about half of the tumours, but malignancy cannot always be predicted by the morphological appearance. Slightly more than half of the islet cell tumours reported in the dog have been associated with clinical signs of hypoglycaemia. Nodular hyperplasia and exocrine adenomas are sometimes difficult to differentiate. Adenomas are considered rare while nodular hyperplasia is common in old animals. PMID:1086150

  20. Application of SPET using technetium-99m sestamibi in brain tumours and comparison with expression of the MDR-1 gene: is it possible to predict the response to chemotherapy in patients with gliomas by means of 99mTc-sestamibi SPET?

    PubMed

    Yokogami, K; Kawano, H; Moriyama, T; Uehara, H; Sameshima, T; Oku, T; Goya, T; Wakisaka, S; Nagamachi, S; Jinnouchi, S; Tamura, S

    1998-04-01

    Technetium-99m sestamibi (MIBI) is thought to be passively taken up by metabolically active tumour cells and effluxed from them by P-glycoprotein (Pgp). This 170-kDa membrane-bound protein, encoded by the MDR-1 gene, acts as an energy-dependent efflux pump for several antineoplastic agents, resulting in multidrug resistance. For this reason, it is of interest whether the tumour's response to chemotherapy can be predicted by MIBI single-photon emission tomography (SPET). In this study, MIBI SPET was compared with thallium-201 (Tl) SPET using magnetic resonance imaging as a guide in 16 patients with untreated brain tumours [ten glioblastomas (GBs), two anaplastic astrocytomas (AAs), two low-grade gliomas (LGASs) and two metastatic brain tumours) and in four patients who had received treatment for with brain tumours (two GBs, two AAs). In addition, we investigated the expression of the MDR-1 gene and its product Pgp in the same patients, and compared the results with MIBI SPET findings. MIBI, as well as Tl, was highly accumulated and retained in the enhanced region of malignant gliomas. In addition, MIBI SPET yielded sharp and well-contrasted images, and the margin of the tumour was more clearly defined than with Tl SPET due to a good signal-to-noise ratio. Follow-up MIBI SPET in patients who had received therapy showed marked uptake in a patient with malignant transformation, who deteriorated clinically. Patients with no uptake on MIBI SPET showed no sign of recurrence. Semiquantitative analysis of untreated patients showed a relationship between the early uptake index (UI, ratio of average count/pixel in the lesion to that in the contralateral area on early images) and the degree of malignancy (early UI = 1.08+/-0.06 in LGASs, 4.10+/-0.84 in AAs, 5.71+/-3.47 in GBs, and 7.52+/-1.52 in metastatic brain tumours). The retention index (RI, ratio of delayed to early UI) of MIBI was significantly lower than that of Tl in metastatic brain tumours (P<0.05), but not in malignant gliomas. Histological and biological investigation of gliomas showed that the MDR-1 gene and its product Pgp were expressed only in normal endothelial cells and not in tumour cells or proliferating endothelial cells; Pgp tended to decrease as the degree of malignancy rose. Hence, the presence of Pgp and the grade of malignancy were inversely related in gliomas. By contrast, immunohistochemical study showed strong accumulation of Pgp in metastatic brain tumour cells. These histopathological findings and MIBI SPET findings are compatible with experimental data; MIBI was washed out by Pgp. The main cause of chemoresistance is probably not an increasing drug efflux by Pgp in gliomas. Thus, MIBI SPET is useful for detecting the active lesions, but may not be useful for predicting the response to chemotherapy in gliomas. PMID:9553170

  1. Classification of a frameshift/extended and a stop mutation in WT1 as gain-of-function mutations that activate cell cycle genes and promote Wilms tumour cell proliferation

    PubMed Central

    Busch, Maike; Schwindt, Heinrich; Brandt, Artur; Beier, Manfred; Görldt, Nicole; Romaniuk, Paul; Toska, Eneda; Roberts, Stefan; Royer, Hans-Dieter; Royer-Pokora, Brigitte

    2014-01-01

    The WT1 gene encodes a zinc finger transcription factor important for normal kidney development. WT1 is a suppressor for Wilms tumour development and an oncogene for diverse malignant tumours. We recently established cell lines from primary Wilms tumours with different WT1 mutations. To investigate the function of mutant WT1 proteins, we performed WT1 knockdown experiments in cell lines with a frameshift/extension (p.V432fsX87 = Wilms3) and a stop mutation (p.P362X = Wilms2) of WT1, followed by genome-wide gene expression analysis. We also expressed wild-type and mutant WT1 proteins in human mesenchymal stem cells and established gene expression profiles. A detailed analysis of gene expression data enabled us to classify the WT1 mutations as gain-of-function mutations. The mutant WT1Wilms2 and WT1Wilms3 proteins acquired an ability to modulate the expression of a highly significant number of genes from the G2/M phase of the cell cycle, and WT1 knockdown experiments showed that they are required for Wilms tumour cell proliferation. p53 negatively regulates the activity of a large number of these genes that are also part of a core proliferation cluster in diverse human cancers. Our data strongly suggest that mutant WT1 proteins facilitate expression of these cell cycle genes by antagonizing transcriptional repression mediated by p53. We show that mutant WT1 can physically interact with p53. Together the findings show for the first time that mutant WT1 proteins have a gain-of-function and act as oncogenes for Wilms tumour development by regulating Wilms tumour cell proliferation. PMID:24619359

  2. Tumours of the skin*

    PubMed Central

    Weiss, E.; Frese, K.

    1974-01-01

    Tumours occur more frequently in the skin than in any other part of the body. Epithelial tumours are described under the following headings: basal cell tumour, squamous cell carcinoma, papilloma, sebaceous gland tumour, tumour of hepatoid glands, sweat gland tumour, mixed tumour of apocrine sweat glands, carcinoma of apocrine sweat glands, tumour of hair follicle, and intracutaneous cornifying epithelioma. Tumours of the melanogenic system are divided into benign melanoma and malignant melanoma, the latter being subdivided into the following types: epithelioid, spindle cell, epithelioid and spindle cell, dendritic, and whorled. ImagesFig. 17Fig. 18Fig. 19Fig. 20Fig. 49Fig. 50Fig. 51Fig. 52Fig. 37Fig. 38Fig. 39Fig. 40Fig. 5Fig. 6Fig. 7Fig. 8Fig. 33Fig. 34Fig. 35Fig. 36Fig. 13Fig. 14Fig. 15Fig. 16Fig. 25Fig. 26Fig. 27Fig. 28Fig. 9Fig. 10Fig. 11Fig. 12Fig. 29Fig. 30Fig. 31Fig. 32Fig. 21Fig. 22Fig. 23Fig. 24Fig. 41Fig. 42Fig. 43Fig. 44Fig. 1Fig. 2Fig. 3Fig. 4Fig. 53Fig. 54Fig. 55Fig. 56Fig. 45Fig. 46Fig. 47Fig. 48 PMID:4547652

  3. Tumour progression and metastasis

    PubMed Central

    Arvelo, Francisco; Sojo, Felipe; Cotte, Carlos

    2016-01-01

    The two biological mechanisms that determine types of malignancy are infiltration and metastasis, for which tumour microenvironment plays a key role in developing and establishing the morphology, growth and invasiveness of a malignancy. The microenvironment is formed by complex tissue containing the extracellular matrix, tumour and non-tumour cells, a signalling network of cytokines, chemokines, growth factors, and proteases that control autocrine and paracrine communication among individual cells, facilitating tumour progression. During the development of the primary tumour, the tumour stroma and continuous genetic changes within the cells makes it possible for them to migrate, having to count on a pre-metastatic niche receptor that allows the tumour’s survival and distant growth. These niches are induced by factors produced by the primary tumour; if it is eradicated, the active niches become responsible for activating the latent disseminated cells. Due to the importance of these mechanisms, the strategies that develop tumour cells during tumour progression and the way in which the microenvironment influences the formation of metastasis are reviewed. It also suggests that the metastatic niche can be an ideal target for new treatments that make controlling metastasis possible. PMID:26913068

  4. Extrarenal Wilms' tumour.

    PubMed

    Suzuki, K; Miyake, H; Tashiro, M; Mori, H; Fukushige, T; Tanimura, R; Yokoyama, S

    1993-01-01

    Extrarenal Wilms' tumour is rare and its imaging has received scant mention in the literature. We describe a 2-year-old boy with a firm mass in the right flank. CT, MRI and ultrasonography showed an inhomogeneous solid mass located in the retroperitoneum, which was separate from the right kidney. Angiography showed an enlarged right gonadal artery and irregularly tortuous vessels in the tumour similar to intrarenal Wilms' tumour ("spider leg" or "creeping vine" appearance). Histopathological examination confirmed an extrarenal Wilms' tumour. PMID:8390643

  5. Adrenomedullin and tumour microenvironment.

    PubMed

    Larráyoz, Ignacio M; Martínez-Herrero, Sonia; García-Sanmartín, Josune; Ochoa-Callejero, Laura; Martínez, Alfredo

    2014-01-01

    Adrenomedullin (AM) is a regulatory peptide whose involvement in tumour progression is becoming more relevant with recent studies. AM is produced and secreted by the tumour cells but also by numerous stromal cells including macrophages, mast cells, endothelial cells, and vascular smooth muscle cells. Most cancer patients present high levels of circulating AM and in some cases these higher levels correlate with a worst prognosis. In some cases it has been shown that the high AM levels return to normal following surgical removal of the tumour, thus indicating the tumour as the source of this excessive production of AM. Expression of this peptide is a good investment for the tumour cell since AM acts as an autocrine/paracrine growth factor, prevents apoptosis-mediated cell death, increases tumour cell motility and metastasis, induces angiogenesis, and blocks immunosurveillance by inhibiting the immune system. In addition, AM expression gets rapidly activated by hypoxia through a HIF-1? mediated mechanism, thus characterizing AM as a major survival factor for tumour cells. Accordingly, a number of studies have shown that inhibition of this peptide or its receptors results in a significant reduction in tumour progression. In conclusion, AM is a great target for drug development and new drugs interfering with this system are being developed. PMID:25475159

  6. Determination of tumour marker genes from gene expression data.

    PubMed

    Cuperlovic-Culf, Miroslava; Belacel, Nabil; Ouellette, Rodney J

    2005-03-15

    Cancer classification has traditionally been based on the morphological study of tumours. However, tumours with similar histological appearances can exhibit different responses to therapy, indicating differences in tumour characteristics on the molecular level. Thus, development of a novel, reliable and precise method for classification of tumours is essential for more successful diagnosis and treatment. The high-throughput gene expression data obtained using microarray technology are currently being investigated for diagnostic applications. However, these large datasets introduce a range of challenges, making data analysis a major part of every experiment for any application, including cancer classification and diagnosis. One of the major concerns in the application of microarrays to tumour diagnostics is the fact that the expression levels of many genes are not measurably affected by carcinogenic changes in the cells. Thus, a crucial step in the application of microarrays to cancer diagnostics is the selection of diagnostic marker genes from the gene expression profiles. These molecular markers give valuable additional information for tumour diagnosis, prognosis and therapy development. PMID:15808822

  7. Malignant Dysembryoplastic Neuroepithelial Tumour in a Zebrafish (Danio rerio)

    PubMed Central

    Peterson, T. S.; Heidel, J. R.; Murray, K. N.; Sanders, J. L.; Anderson, W. I.; Kent, M. L.

    2014-01-01

    Summary Neuroectodermal tumours in man, including medulloblastoma, medulloepithelioma, neuroblastoma, esthesioneuroblastoma, primitive neuroectodermal tumour and dysembryoplastic neuroepithelial tumour, typically occur in children and young adults. These tumour types are occasionally observed in juvenile and adult zebrafish (Danio rerio), either as induced tumours in carcinogen-exposed zebrafish or as an incidental finding in zebrafish ≥ 2 years of age. An adult zebrafish submitted for routine histological examination was sent for a second opinion consultation after an uncharacteristic brain mass was identified. Microscopically, the expansile and infiltrative extracortical mass arising from the cerebellum had a diffuse microcystic pattern with solid hypercellular regions occupying 80% of the extrameningeal space and effacing the endomeninx and significantly displacing the metencephalon. The mass was composed of dense sheets of oligodendrocyte-like cells, random neurons and pseudocysts containing ‘floating neurons’ within a scant mucinous matrix. Neoplastic cells demonstrated positive perinuclear and intracytoplasmic expression of S-100. Malignant dysembryoplastic neuroepithelial tumour was diagnosed based upon the histologic features of the brain mass, which were indistinguishable from the human tumour. To our knowledge, this is the first report of a dysembryoplastic neuroepithelial tumour in a zebrafish. PMID:22819012

  8. Neonatal exposure to estradiol-17β modulates tumour necrosis factor alpha and cyclooxygenase-2 expression in brain and also in ovaries of adult female rats.

    PubMed

    Shridharan, Radhika Nagamangalam; Krishnagiri, Harshini; Govindaraj, Vijayakumar; Sarangi, SitiKantha; Rao, Addicam Jagannadha

    2016-02-01

    The sexually dimorphic organization in perinatal rat brain is influenced by steroid hormones. Exposure to high levels of estrogen or endocrine-disrupting compounds during perinatal period may perturb this process, resulting in compromised reproductive physiology and behavior as observed in adult In our recent observation neonatal exposure of the female rats to estradiol-17β resulted in down-regulation of TNF-α, up-regulation of COX-2 and increase in SDN-POA size in pre-optic area in the adulthood. It is known that the control of reproductive performance in female involves a complex interplay of the hypothalamus, pituitary, and ovary. The present study was undertaken to understand the possible molecular mechanism involved in changes observed in the ovarian morphology and expression of selected genes in the ovary. Administration of estradiol-17β (100 μg) on day 2 and 3 after birth revealed up-regulation of ER-α, ER-β, COX-2 and down-regulation of TNF-α expression. Also the decrease in the ovarian weight, altered ovarian morphology and changes in the 2D protein profiles were also seen. This is apparently the first report documenting that neonatal estradiol exposure modulates TNF-α and COX-2 expression in the ovary as seen during adult stage. Our results permit us to suggest that cues originating from the modified brain structure due to neonatal exposure of estradiol-17β remodel the ovary at the molecular level in such a way that there is a disharmony in the reproductive function during adulthood and these changes are perennial and can lead to infertility and changes of reproductive behavior. PMID:26872318

  9. Gastrointestinal stromal tumours: an update.

    PubMed

    Rubin, B P

    2006-01-01

    Recently, there has been intense interest in the study of gastrointestinal stromal tumour (GIST); one might call it a virtual GIST revolution. This is due largely to the realization that most GISTs express KIT and harbour activating c-KIT (KIT) or platelet-derived growth factor receptor-alpha (PDGFRA) receptor tyrosine kinase mutations that can be targeted by small molecule pharmacological inhibitors. Pathologists have benefited greatly from this revolution, mainly in the form of an improved ability to classify GISTs and, even more recently, in understanding the molecular underpinnings that underlie many fascinating clinical and pathological correlations. It is the purpose of this review to summarize recent developments in GIST classification and the molecular pathogenesis of GIST. PMID:16359540

  10. Enhancing the classification accuracy of steady-state visual evoked potential-based brain-computer interfaces using phase constrained canonical correlation analysis

    NASA Astrophysics Data System (ADS)

    Pan, Jie; Gao, Xiaorong; Duan, Fang; Yan, Zheng; Gao, Shangkai

    2011-06-01

    In this study, a novel method of phase constrained canonical correlation analysis (p-CCA) is presented for classifying steady-state visual evoked potentials (SSVEPs) using multichannel electroencephalography (EEG) signals. p-CCA is employed to improve the performance of the SSVEP-based brain-computer interface (BCI) system using standard CCA. SSVEP response phases are estimated based on the physiologically meaningful apparent latency and are added as a reliable constraint into standard CCA. The results of EEG experiments involving 10 subjects demonstrate that p-CCA consistently outperforms standard CCA in classification accuracy. The improvement is up to 6.8% using 1-4 s data segments. The results indicate that the reliable measurement of phase information is of importance in SSVEP-based BCIs.

  11. Extrafollicular adenomatoid odontogenic tumour

    PubMed Central

    Prasad, Guru; Nair, Preeti; Thomas, Shaji; Gharote, Harshkant; Singh, Neha; Bhambal, Annette

    2011-01-01

    Adenomatoid odontogenic tumour (AOT) is an uncommon, benign tumour that represents 3–7% of all odontogenic tumours. It is slow growing, occurs twice as common in females and usually in the second decade of life. There are three subclinical types of this tumour with identical histology: follicular type (73%), extrafollicular variant (24%) and peripheral form (3%). Here, the authors have presented two rare cases of extrafollicular varieties of AOT in 25-year-old female patients, of which one was situated in the maxillary canine area and the other one situated in an unusual location of mandibular premolar area. Such lesions may be confused as an odontogenic cyst and should be carefully differentiated from other benign and malignant lesions arising in this region. PMID:22693275

  12. Maxillary adenomatoid odontogenic tumour.

    PubMed

    Barodiya, Animesh; Banda, Naveen Reddy; Banda, Vanaja Reddy; Vyawahare, Saket

    2013-01-01

    An adenomatoid odontogenic tumour (AOT) is a benign, slow-growing, relatively rare oral tumour, which accounts for about 3-7% of all odontogenic tumours as reported in the literature. It is an unusual benign neoplasm which shares clinical and radiographical characteristics with odontogenic cystic lesions denoting a distinct behaviour. The three variants-follicular, extrafollicular and peripheral-present with identical histological findings. This report describes a patient with an AOT in the anterior maxilla. Radiographically, the lesion was characterised by a well circumscribed unilocular radiolucent area displacing left maxillary lateral incisor, canine and first premolars. The final diagnosis was AOT. The lesion was enucleated under local anaesthesia. The patient was followed-up for one year. This paper also provides a refresher for general dental practitioners about various diagnostic aspects of this tumour and highlights the controversies regarding its origin and management in the light of recent findings. PMID:23771977

  13. The Pathology of Tumours of the Urinary Tract

    PubMed Central

    Newcomb, W. D.

    1939-01-01

    Attention is called to the difference between the pathologist's and the radiologist's point of view. The reasons for this difference are discussed with special emphasis on renal tumours. Classification of renal tumours. The first main groups are innocent and malignant. Are these really clear-cut or do they blend into one another? The commoner innocent renal tumours are adenoma, fibroma, myoma, lipoma, and angioma. These are rarely of any clinical importance but adenoma is a possible source of hypernephroma. Many elaborate classifications of cancer of the kidney have been proposed but the following four groups are sufficient for most puposes: Carcinoma, hypernephroma, sarcoma, and teratoid tumours. Much the commonest malignant renal tumour in adults is the hypernephroma, thought by Grawitz and others to be derived from ectopic adrenal rests. There is still no agreement concerning their origin but three views are held at the present time: (a) All are carcinoma of renal tubules. (b) Some are derived from renal tubules and some from ectopic adrenal. (c) All are formed from adrenal tissue. These views are discussed with special reference to material in St. Mary's Hospital Museum, and it is suggested that the first view is the most probable although the second cannot be excluded. The teratoid tumours are the commonest in infants and swine. The differences between them and hypernephromata are described. The renal Pelvis, ureter, and bladder all have tumours of the same type and can conveniently be considered together. Connective tissue tumours, both innocent and malignant, are very rare. Papilloma and carcinoma are rare in the pelvis and ureter, but commoner in the bladder. The relation between these two tumours is discussed. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11Fig. 12Fig. 13Fig. 14Fig. 15Fig. 16Fig. 17Fig. 18 PMID:19992130

  14. Diverse effects of hypothermia therapy in patients with severe traumatic brain injury based on the computed tomography classification of the traumatic coma data bank.

    PubMed

    Suehiro, Eiichi; Koizumi, Hiroyasu; Fujisawa, Hirosuke; Fujita, Motoki; Kaneko, Tadashi; Oda, Yasutaka; Yamashita, Susumu; Tsuruta, Ryosuke; Maekawa, Tsuyoshi; Suzuki, Michiyasu

    2015-03-01

    A multicenter randomized controlled trial of patients with severe traumatic brain injury who received therapeutic hypothermia or fever control was performed from 2002 to 2008 in Japan (BHYPO). There was no difference in the therapeutic effect on traumatic brain injury between the two groups. The efficacy of hypothermia treatment and the objective of the treatment were reexamined based on a secondary analysis of the BHYPO trial in 135 patients (88 treated with therapeutic hypothermia and 47 with fever control). This analysis was performed to examine clinical outcomes according to the CT classification of the Traumatic Coma Data Bank on admission. Clinical outcomes were evaluated with the Glasgow Outcome Scale and mortality at 6 months after injury. Good recovery and moderate disability were defined as favorable outcomes. Favorable outcomes in young patients (?50 years old) with evacuated mass lesions significantly increased from 33.3% with fever control to 77.8% with therapeutic hypothermia. Patients with diffuse injury III who were treated with therapeutic hypothermia, however, had significantly higher mortality than patients treated with fever control. It was difficult to control intracranial pressure with hypothermia for patients with diffuse injury III, but hypothermia was effective for young patients with an evacuated mass lesion. PMID:25233298

  15. EEG-Based Classification of Motor Imagery Tasks Using Fractal Dimension and Neural Network for Brain-Computer Interface

    NASA Astrophysics Data System (ADS)

    Phothisonothai, Montri; Nakagawa, Masahiro

    In this study, we propose a method of classifying a spontaneous electroencephalogram (EEG) approach to a brain-computer interface. Ten subjects, aged 21-32 years, volunteered to imagine left-and right- hand movements. An independent component analysis based on a fixed-point algorithm is used to eliminate the activities found in the EEG signals. We use a fractal dimension value to reveal the embedded potential responses in the human brain. The different fractal dimension values between the relaxing and imaging periods are computed. Featured data is classified by a three-layer feed-forward neural network based on a simple backpropagation algorithm. Two conventional methods, namely, the use of the autoregressive (AR) model and the band power estimation (BPE) as features, and the linear discriminant analysis (LDA) as a classifier, are selected for comparison in this study. Experimental results show that the proposed method is more effective than the conventional methods.

  16. Borderline or malignant ovarian tumour? A case report of decision making with morphometry.

    PubMed Central

    Baak, J P; Van der Ley, G

    1984-01-01

    A young woman presented with bilateral ovarian tumours. Multiple sections of each tumour were shown to many pathologists for consultation; some considered the tumours to be borderline, whereas others thought that one or both of them was malignant. Morphometry showed that the numerical classification probabilities for borderline tumour were 0.78 for the left ovarian tumour and 0.85 in the right. The lesions were therefore regarded as borderline tumours and no additional chemotherapy was given. Three years after the second operation the patient is alive and well without clinical or biochemical evidence of recurrence. Most patients with borderline tumours who die from the disease do so in the first two years after the operation. This young patient was prevented from severe overtreatment by the application of morphometry, illustrating its use in this area of diagnostic gynaecopathology. Images PMID:6490950

  17. Machine Learning Classification of Cirrhotic Patients with and without Minimal Hepatic Encephalopathy Based on Regional Homogeneity of Intrinsic Brain Activity

    PubMed Central

    Liu, Jun; Sun, Tao; Shen, Qun-Tai

    2016-01-01

    Machine learning-based approaches play an important role in examining functional magnetic resonance imaging (fMRI) data in a multivariate manner and extracting features predictive of group membership. This study was performed to assess the potential for measuring brain intrinsic activity to identify minimal hepatic encephalopathy (MHE) in cirrhotic patients, using the support vector machine (SVM) method. Resting-state fMRI data were acquired in 16 cirrhotic patients with MHE and 19 cirrhotic patients without MHE. The regional homogeneity (ReHo) method was used to investigate the local synchrony of intrinsic brain activity. Psychometric Hepatic Encephalopathy Score (PHES) was used to define MHE condition. SVM-classifier was then applied using leave-one-out cross-validation, to determine the discriminative ReHo-map for MHE. The discrimination map highlights a set of regions, including the prefrontal cortex, anterior cingulate cortex, anterior insular cortex, inferior parietal lobule, precentral and postcentral gyri, superior and medial temporal cortices, and middle and inferior occipital gyri. The optimized discriminative model showed total accuracy of 82.9% and sensitivity of 81.3%. Our results suggested that a combination of the SVM approach and brain intrinsic activity measurement could be helpful for detection of MHE in cirrhotic patients. PMID:26978777

  18. Islet cell tumours.

    PubMed

    Ekeblad, Sara

    2010-01-01

    Pancreatic endocrine tumours can cause hormonal symptoms by over-secretion of hormones. They are less aggressive than exocrine pancreatic cancer, but carry a variable prognosis. The tumours are either sporadic or hereditary, as part of the multiple endocrine neoplasia type 1 syndrome. Despite the rarity of these tumours, they evoke significant interest in the research community and important advances have been made over the past years. This chapter provides an overview of the tumours and recent advances in the field. Hereditary forms of pancreatic endocrine tumours are caused by mutations in the MEN1 gene. Menin, the protein encoded by this gene, has been shown to interact with numerous transcription factors and proteins involved in cell-cycle control, shedding some light on the importance of the protein. Several genes have been shown to be up- or down-regulated, suggesting candidates to be further evaluated for a role in tumourigenesis. Several advances have been made in prognostication; a tumour-node-metastasis system has been evaluated and seems to have prognostic value, and several new molecular prognostic markers are under evaluation. It is hoped that the tumour-node-metastasis system and other prognostic markers will be adopted in clinical routine and improve prognostication and treatment choices. Surgery is still the only cure, but several new palliative drugs and interventions are in use or under investigation. Radiofrequency ablation is increasingly used for liver metastases, and a number of new chemotherapy drugs are being tested. Despite improvements in treatment, no clear improvement in survival has been demonstrated. PMID:20217524

  19. Case Report: Meningioma with Intra-tumoural Haemorrhage Secondary to Ruptured Distal Anterior Cerebral Artery Aneurysm

    PubMed Central

    Alnaami, Ibrahim; Ho, Ping; Lu, Jian-Qiang; Wheatley, Blaise

    2013-01-01

    Background: Brain tumours that are associated with cerebral aneurysms are rare occurrences, whereas the coexistence of brain tumours and intra-tumoural aneurysms is even rarer. There have been 12 brain tumour cases that have been reported in the literature that describe an aneurysm within a brain tumour, with 4 of these tumours being meningiomas. Case description: A 34-year-old male patient presented with sudden-onset headache, and an inter-hemispheric meningioma with intra-tumoural bleeding was found due to a ruptured embedded anterior cerebral artery aneurysm. The aneurysm was diagnosed incidentally on the third cerebral angiogram, while the initial 2 angiograms were negative. The patient was treated with endovascular aneurysm embolisation that was followed by tumour resection. Conclusion: This paper is the first case report to describe the coexistence of a meningioma and an aneurysm, which presented with intra-tumoural haemorrhage that was negative on the initial cerebral angiogram. Unlike previous case reports, the aneurysm in this case was located with an anterior cerebral artery distribution. PMID:24179557

  20. Predicting tumour response

    PubMed Central

    Law, W. Phillip; Miles, Kenneth A.

    2013-01-01

    Abstract Response prediction is an important emerging concept in oncologic imaging, with tailored, individualized treatment regimens increasingly becoming the standard of care. This review aims to define tumour response and illustrate the ways in which imaging techniques can demonstrate tumour biological characteristics that provide information on the likely benefit to be received by treatment. Two imaging approaches are described: identification of therapeutic targets and depiction of the treatment-resistant phenotype. The former approach is exemplified by the use of radionuclide imaging to confirm target expression before radionuclide therapy but with angiogenesis imaging and imaging correlates for genetic response predictors also demonstrating potential utility. Techniques to assess the treatment-resistant phenotype include demonstration of hypoperfusion with dynamic contrast-enhanced computed tomography and magnetic resonance imaging (MRI), depiction of necrosis with diffusion-weighted MRI, imaging of hypoxia and tumour adaption to hypoxia, and 99mTc-MIBI imaging of P-glycoprotein mediated drug resistance. To date, introduction of these techniques into clinical practice has often been constrained by inadequate cross-validation of predictive criteria and lack of verification against appropriate response end points such as survival. With further refinement, imaging predictors of response could play an important role in oncology, contributing to individualization of therapy based on the specific tumour phenotype. This ability to predict tumour response will have implications for improving efficacy of treatment, cost-effectiveness and omission of futile therapy. PMID:24061161

  1. Classification of hemodynamics from dynamic-susceptibility-contrast magnetic resonance (DSC-MR) brain images using noiseless independent factor analysis.

    PubMed

    Chou, Yen-Chun; Teng, Michael Mu Huo; Guo, Wan-Yuo; Hsieh, Jen-Chuen; Wu, Yu-Te

    2007-06-01

    Dynamic-susceptibility-contrast (DSC) magnetic resonance imaging records signal changes on images when the injected contrast-agent particles pass through a human brain. The temporal signal changes on different brain tissues manifest distinct blood-supply patterns which are vital for the profound analysis of cerebral hemodynamics. Under the assumption of the spatial independence among these patterns, noiseless independent factor analysis (IFA) was first applied to decompose the DSC-MR data into different independent-factor images with corresponding signal-time curves. A major tissue type, such as artery, gray matter, white matter, vein, sinus, and choroid plexus, etc., on each independent-factor image was further segmented out by an optimal threshold. Based on the averaged signal-time curve on the arterial area, the cerebral hemodynamic parameters, such as relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), and mean transit time (MTT), were computed and their averaged ratios between gray matter and white matter for normal subjects were in good agreement with those in the literature. Data of a stenosis patient before and after treatment were analyzed and the result illustrates that this method is effective in extracting spatiotemporal blood-supply patterns which improves differentiation of pathological and non-pathological hemodynamics. PMID:17433760

  2. The determinants of tumour immunogenicity

    PubMed Central

    Blankenstein, Thomas; Coulie, Pierre G.; Gilboa, Eli; Jaffee, Elizabeth M.

    2013-01-01

    Many standard and targeted therapies, as well as radiotherapy, have been shown to induce an anti-tumour immune response, and immunotherapies rely on modulating the host immune system to induce an anti-tumour immune response. However, the immune response to such therapies is often reliant on the immunogenicity of a tumour. Tumour immunogenicity varies greatly between cancers of the same type in different individuals and between different types of cancer. So, what do we know about tumour immunogenicity and how might we therapeutically improve tumour immunogenicity? We asked four leading cancer immunologists around the world for their opinions on this important issue. PMID:22378190

  3. Brain source localization: A new method based on MUltiple SIgnal Classification algorithm and spatial sparsity of the field signal for electroencephalogram measurements

    NASA Astrophysics Data System (ADS)

    Vergallo, P.; Lay-Ekuakille, A.

    2013-08-01

    Brain activity can be recorded by means of EEG (Electroencephalogram) electrodes placed on the scalp of the patient. The EEG reflects the activity of groups of neurons located in the head, and the fundamental problem in neurophysiology is the identification of the sources responsible of brain activity, especially if a seizure occurs and in this case it is important to identify it. The studies conducted in order to formalize the relationship between the electromagnetic activity in the head and the recording of the generated external field allow to know pattern of brain activity. The inverse problem, that is given the sampling field at different electrodes the underlying asset must be determined, is more difficult because the problem may not have a unique solution, or the search for the solution is made difficult by a low spatial resolution which may not allow to distinguish between activities involving sources close to each other. Thus, sources of interest may be obscured or not detected and known method in source localization problem as MUSIC (MUltiple SIgnal Classification) could fail. Many advanced source localization techniques achieve a best resolution by exploiting sparsity: if the number of sources is small as a result, the neural power vs. location is sparse. In this work a solution based on the spatial sparsity of the field signal is presented and analyzed to improve MUSIC method. For this purpose, it is necessary to set a priori information of the sparsity in the signal. The problem is formulated and solved using a regularization method as Tikhonov, which calculates a solution that is the better compromise between two cost functions to minimize, one related to the fitting of the data, and another concerning the maintenance of the sparsity of the signal. At the first, the method is tested on simulated EEG signals obtained by the solution of the forward problem. Relatively to the model considered for the head and brain sources, the result obtained allows to have a significant improvement compared to the classical MUSIC method, with a small margin of uncertainty about the exact location of the sources. In fact, the constraints of the spatial sparsity on the signal field allow to concentrate power in the directions of active sources, and consequently it is possible to calculate the position of the sources within the considered volume conductor. Later, the method is tested on the real EEG data too. The result is in accordance with the clinical report even if improvements are necessary to have further accurate estimates of the positions of the sources.

  4. Tumour related cutaneous elastophagocytosis.

    PubMed

    Sweeney, E C; McDermott, M

    1996-01-01

    Dermal granulomatous inflammation was identified immediately adjacent to seven (77%) of nine atypical fibroxanthomas arising in sun damaged skin. Concomitant elastophagocytosis was observed in five (56%) of these seven patients. Similar inflammation with elastophagocytosis was found in association with only two (6%) of 36 epithelial tumours arising on the same background (10 basal and 10 squamous cell carcinomas, 10 nodular malignant melanomas, and six keratocanthomas). Granulomatous inflammation is an unusual dermal reaction to tumour and elastophagocytosis is rare. The fact that both of these features occur with inordinate frequency in association with atypical fibroxanthomas, when compared with other, more common skin tumours, suggests that atypical fibroxanthomas might modulate the inflammatory response, either passively, by its dermal location, or actively, by secreting locally effective cytokines. PMID:8666693

  5. Tumour induced osteomalacia.

    PubMed

    Masood, Muhammad Qamar; Ram, Nanik; Ali, Syed Ahsan

    2015-02-01

    Tumour-induced osteomalacia (TIO) is a rare paraneoplastic syndrome usually presenting with bone pain, fracture of bones and muscle weakness. It is caused by high serum levels of fibroblast growth factor 23 (FGF- 23), which is a hormone-regulating phosphate, and vitamin D. FGF-23 is secreted by several tumours, especially benign mesenchymal tumours which are very small and difficult to locate. There is a significant delay from onset of symptoms to the diagnosis of this entity dueto occult nature of this disease. We present a case of young male who presented with long history of progressively worsening muscular pain and weakness, rendering the patient confined to bed. Our aim of presenting this patient as a case report is to make physicians realise that any patient with unexplained muscular weakness and pain must undergo workup for TIO, including serum phosphate measurement, as this is a rare but potentially curable disease. PMID:25842564

  6. Electrode replacement does not affect classification accuracy in dual-session use of a passive brain-computer interface for assessing cognitive workload

    PubMed Central

    Estepp, Justin R.; Christensen, James C.

    2015-01-01

    The passive brain-computer interface (pBCI) framework has been shown to be a very promising construct for assessing cognitive and affective state in both individuals and teams. There is a growing body of work that focuses on solving the challenges of transitioning pBCI systems from the research laboratory environment to practical, everyday use. An interesting issue is what impact methodological variability may have on the ability to reliably identify (neuro)physiological patterns that are useful for state assessment. This work aimed at quantifying the effects of methodological variability in a pBCI design for detecting changes in cognitive workload. Specific focus was directed toward the effects of replacing electrodes over dual sessions (thus inducing changes in placement, electromechanical properties, and/or impedance between the electrode and skin surface) on the accuracy of several machine learning approaches in a binary classification problem. In investigating these methodological variables, it was determined that the removal and replacement of the electrode suite between sessions does not impact the accuracy of a number of learning approaches when trained on one session and tested on a second. This finding was confirmed by comparing to a control group for which the electrode suite was not replaced between sessions. This result suggests that sensors (both neurological and peripheral) may be removed and replaced over the course of many interactions with a pBCI system without affecting its performance. Future work on multi-session and multi-day pBCI system use should seek to replicate this (lack of) effect between sessions in other tasks, temporal time courses, and data analytic approaches while also focusing on non-stationarity and variable classification performance due to intrinsic factors. PMID:25805963

  7. Radiotherapy for ocular tumours.

    PubMed

    Stannard, C; Sauerwein, W; Maree, G; Lecuona, K

    2013-02-01

    Ocular tumours present a therapeutic challenge because of the sensitive tissues involved and the necessity to destroy the tumour while minimising visual loss. Radiotherapy (RT) is one of several modalites used apart from surgery, laser, cryotherapy, and chemotherapy. Both external beam RT (EBRT) and brachytherapy are used. Tumours of the bulbar conjunctiva, squamous carcinoma and malignant melanoma, can be treated with a radioactive plaque: strontium-90, ruthenium-106 (Ru-106), or iodine-125 (I-125), after excision. If the tumour involves the fornix or tarsal conjunctiva, proton therapy can treat the conjunctiva and spare most of the eye. Alternatively, an I-125 interstitial implant can be used with shielding of the cornea and lens. Conjunctival mucosal-associated lymphoid tissue lymphoma can be treated with an anterior electron field with lens shielding and 25-30 Gray (Gy) in 2?Gy fractions. Discrete retinoblastoma (RB), too large for cryotherapy or thermolaser, or recurrent after these modalities, can be treated with plaque therapy, I-125, or Ru-106. For large RB, multiple tumours, or vitreous seeds the whole eye can be treated with an I-125 applicator, sparing the bony orbit, or with EBRT, under anaesthetic, using X-rays or proton therapy with vacuum contact lenses to fix the eyes in the required position. Post-enucleated orbits at risk for recurrent RB can be treated with an I-125 implant with shielding to reduce the dose to the bony orbit. Uveal malignant melanomas can be treated with plaque or proton therapy with excellent local control. Preservation of vision will depend on the initial size and location of the tumour. PMID:23174750

  8. Immunology of naturally transmissible tumours.

    PubMed

    Siddle, Hannah V; Kaufman, Jim

    2015-01-01

    Naturally transmissible tumours can emerge when a tumour cell gains the ability to pass as an infectious allograft between individuals. The ability of these tumours to colonize a new host and to cross histocompatibility barriers contradicts our understanding of the vertebrate immune response to allografts. Two naturally occurring contagious cancers are currently active in the animal kingdom, canine transmissible venereal tumour (CTVT), which spreads among dogs, and devil facial tumour disease (DFTD), among Tasmanian devils. CTVT are generally not fatal as a tumour-specific host immune response controls or clears the tumours after transmission and a period of growth. In contrast, the growth of DFTD tumours is not controlled by the Tasmanian devil's immune system and the disease causes close to 100% mortality, severely impacting the devil population. To avoid the immune response of the host both DFTD and CTVT use a variety of immune escape strategies that have similarities to many single organism tumours, including MHC loss and the expression of immunosuppressive cytokines. However, both tumours appear to have a complex interaction with the immune system of their respective host, which has evolved over the relatively long life of these tumours. The Tasmanian devil is struggling to survive with the burden of this disease and it is only with an understanding of how DFTD passes between individuals that a vaccine might be developed. Further, an understanding of how these tumours achieve natural transmissibility should provide insights into general mechanisms of immune escape that emerge during tumour evolution. PMID:25187312

  9. Immunology of naturally transmissible tumours

    PubMed Central

    Siddle, Hannah V; Kaufman, Jim

    2015-01-01

    Naturally transmissible tumours can emerge when a tumour cell gains the ability to pass as an infectious allograft between individuals. The ability of these tumours to colonize a new host and to cross histocompatibility barriers contradicts our understanding of the vertebrate immune response to allografts. Two naturally occurring contagious cancers are currently active in the animal kingdom, canine transmissible venereal tumour (CTVT), which spreads among dogs, and devil facial tumour disease (DFTD), among Tasmanian devils. CTVT are generally not fatal as a tumour-specific host immune response controls or clears the tumours after transmission and a period of growth. In contrast, the growth of DFTD tumours is not controlled by the Tasmanian devil's immune system and the disease causes close to 100% mortality, severely impacting the devil population. To avoid the immune response of the host both DFTD and CTVT use a variety of immune escape strategies that have similarities to many single organism tumours, including MHC loss and the expression of immunosuppressive cytokines. However, both tumours appear to have a complex interaction with the immune system of their respective host, which has evolved over the relatively long life of these tumours. The Tasmanian devil is struggling to survive with the burden of this disease and it is only with an understanding of how DFTD passes between individuals that a vaccine might be developed. Further, an understanding of how these tumours achieve natural transmissibility should provide insights into general mechanisms of immune escape that emerge during tumour evolution. PMID:25187312

  10. [Molecular tumour therapy].

    PubMed

    Michel, C; Neubauer, A; Burchert, A

    2015-12-01

    In recent years, molecular tumour therapy has dramatically improved the treatment of various types of cancer. Molecular therapy is expected to attack malignant cells more specifically with fewer side effects than conventional chemotherapy. Both kinase inhibitors and monoclonal antibodies are key components of today's molecular cancer therapy. These substances cannot fully overcome the major tumour-biological problems, e.g. therapy resistance. However, as can be vividly seen with the example of immune checkpoint inhibitors, the rational design of molecularly designed drugs will considerably change therapeutic practice in oncology, albeit at the expense of exponentially growing health care costs. PMID:26585240

  11. Brain-state classification and a dual-state decoder dramatically improve the control of cursor movement through a brain-machine interface

    NASA Astrophysics Data System (ADS)

    Sachs, Nicholas A.; Ruiz-Torres, Ricardo; Perreault, Eric J.; Miller, Lee E.

    2016-02-01

    Objective. It is quite remarkable that brain machine interfaces (BMIs) can be used to control complex movements with fewer than 100 neurons. Success may be due in part to the limited range of dynamical conditions under which most BMIs are tested. Achieving high-quality control that spans these conditions with a single linear mapping will be more challenging. Even for simple reaching movements, existing BMIs must reduce the stochastic noise of neurons by averaging the control signals over time, instead of over the many neurons that normally control movement. This forces a compromise between a decoder with dynamics allowing rapid movement and one that allows postures to be maintained with little jitter. Our current work presents a method for addressing this compromise, which may also generalize to more highly varied dynamical situations, including movements with more greatly varying speed. Approach. We have developed a system that uses two independent Wiener filters as individual components in a single decoder, one optimized for movement, and the other for postural control. We computed an LDA classifier using the same neural inputs. The decoder combined the outputs of the two filters in proportion to the likelihood assigned by the classifier to each state. Main results. We have performed online experiments with two monkeys using this neural-classifier, dual-state decoder, comparing it to a standard, single-state decoder as well as to a dual-state decoder that switched states automatically based on the cursor’s proximity to a target. The performance of both monkeys using the classifier decoder was markedly better than that of the single-state decoder and comparable to the proximity decoder. Significance. We have demonstrated a novel strategy for dealing with the need to make rapid movements while also maintaining precise cursor control when approaching and stabilizing within targets. Further gains can undoubtedly be realized by optimizing the performance of the individual movement and posture decoders.

  12. Tumour Cell Heterogeneity

    PubMed Central

    Gay, Laura; Baker, Ann-Marie; Graham, Trevor A.

    2016-01-01

    The population of cells that make up a cancer are manifestly heterogeneous at the genetic, epigenetic, and phenotypic levels. In this mini-review, we summarise the extent of intra-tumour heterogeneity (ITH) across human malignancies, review the mechanisms that are responsible for generating and maintaining ITH, and discuss the ramifications and opportunities that ITH presents for cancer prognostication and treatment. PMID:26973786

  13. EEG-Based Classification of New Imagery Tasks Using Three-Layer Feedforward Neural Network Classifier for Brain-Computer Interface

    NASA Astrophysics Data System (ADS)

    Phothisonothai, Montri; Nakagawa, Masahiro

    2006-10-01

    In this paper proposes the classification method of new imagery tasks for simple binary commands approach to a brain-computer interface (BCI). An analysis of imaginary tasks as “yes/no” have been proposed. Since BCI is very helpful technology for the patients who are suffering from severe motor disabilities. The BCI applications can be realized by using an electroencephalogram (EEG) signals recording at the scalp surface through the electrodes. Six healthy subjects (three males and three females), aged 23-30 years, were volunteered to participate in the experiment. During the experiment, 10-questions were used to be stimuli. The feature extraction of the event-related synchronization and event-related desynchronization (ERD/ERS) responses can be determined by the slope coefficient and Euclidian distance (SCED) method. The method uses the three-layer feedforward neural network based on a simple backpropagation algorithm to classify the two feature vectors. The experimental results of the proposed method show the average accuracy rates of 81.5 and 78.8% when the subjects imagine to “yes” and “no”, respectively.

  14. High APRIL expression correlates with unfavourable survival of gastrointestinal stromal tumour.

    PubMed

    Xian, Hua; Zhang, Huilin; Zhu, Huijun; Wang, Xudong; Tang, Xiaojun; Mao, Yuan; Zhu, Jin

    2014-12-01

    A proliferation inducing ligand (APRIL) is a member of the tumour necrosis factor superfamily. High APRIL expression has been found to correlate with tumour development, suggesting that APRIL participates in oncogenesis. However, little is known about APRIL expression in gastrointestinal stromal tumours (GISTs) or the relationship between APRIL expression and the clinical characteristics of GIST. Therefore, we assessed the expression of APRIL immunohistochemically using a tissue microarray from 178 patients with GIST and evaluated the relationship between APRIL expression and patient prognosis. Strong APRIL expression was observed in 42.7% of GISTs, with APRIL expression significantly associated with tumour diameter, gross classification and tumour grade (p < 0.05 each). Kaplan-Meier analysis suggested that low APRIL expression and tumour size <5 cm were associated with longer overall survival. These findings indicate that APRIL expression is correlated with malignant GIST phenotypes and it may serve as an unfavourable prognostic marker in patients with GIST. PMID:25393252

  15. Craniopharyngioma and epidermoid tumour in same child: a rare association

    PubMed Central

    Singh, Deepak Kumar; Singh, Neha; Parihar, Anit; Singh, Ragini

    2013-01-01

    Simultaneous occurrence of histologically different primary brain tumours is rare, and its preoperative diagnosis is still challenging. The explanations for the simultaneous occurrence of different primary intracranial tumours in the absence of phacomatoses or prior radiation exposure are at present hypothetical, and these tumours could be simply coincidental. Herein, we report a case of a boy presenting with features of raised intracranial pressure and right-sided sensorineural hearing loss. Brain MRI revealed two different neoplastic pathologies at different sites: an intrasellar and suprasellar craniopharyngioma and a right cerebello-pontine angle epidermoid. To the best of our knowledge, this is the first report in literature of a craniopharyngioma coexisting with an epidermoid, in the same individual. PMID:23737578

  16. Fibre intake and incident colorectal cancer depending on fibre source, sex, tumour location and Tumour, Node, Metastasis stage.

    PubMed

    Vulcan, Alexandra; Brändstedt, Jenny; Manjer, Jonas; Jirström, Karin; Ohlsson, Bodil; Ericson, Ulrika

    2015-09-28

    Studies on fibre intake and incident colorectal cancer (CRC) indicate inverse associations. Differences by tumour stage have not been examined. We examined associations between fibre intake and its sources, and incidental CRC. Separate analyses were carried out on the basis of sex, tumour location and the Tumour, Node, Metastasis (TNM) classification. The Malmö Diet and Cancer Study is a population-based cohort study, including individuals aged 45-74 years. Dietary data were collected through a modified diet history method. The TNM classification was obtained from pathology/clinical records and re-evaluated. Among 27 931 individuals (60% women), we found 728 incident CRC cases during 428 924 person-years of follow-up. Fibre intake was inversely associated with CRC risk (P(trend) = 0.026). Concerning colon cancer, we observed borderline interaction between fibre intake and sex (P = 0.052) and significant protective association restricted to women (P(trend) = 0.013). Intake of fruits and berries was inversely associated with colon cancer in women (P(trend) = 0.022). We also observed significant interactions between intakes of fibre (P = 0.048) and vegetables (P = 0.039) and sex on rectal cancer, but no significant associations were seen between intake of fibre, or its sources, in either of the sexes. Except for inverse associations between intake of fibre-rich cereal products and N0- and M0-tumours, we did not observe significant associations with different TNM stages. Our findings suggest different associations between fibre intake and CRC depending on sex, tumour site and fibre source. High fibre intake, especially from fruits and berries, may, above all, prevent tumour development in the colon in women. No clear differences by TNM classification were detected. PMID:26281852

  17. Screening for uterine tumours.

    PubMed

    Van den Bosch, Thierry; Coosemans, An; Morina, Memli; Timmerman, Dirk; Amant, Frederic

    2012-04-01

    The most prevalent uterine tumours are leiomyomas, which are benign and have a prevalence of about 50% at menopause. The incidence of endometrial cancer and uterine sarcomas is about 25 per 100,000 and 0.7 per 100,000, respectively. Reported risk factors for endometrial cancer are advanced age, unopposed oestrogen stimulation, late menopause, obesity, diabetes mellitus, nulliparity, feminising ovarian tumours, polycystic ovarian syndrome, tamoxifen and belonging to a hereditary non-polyposis colorectal cancer family. Unopposed oestrogen stimulation and tamoxifen have also been confirmed to induce uterine sarcomas. Cervical cytology, endometrial sampling and ultrasound have been proposed in the early diagnosis of endometrial cancer. No pathognomonic ultrasound, magnetic resonance imaging or computed tomography features are able to differentiate between a leiomyoma and a uterine sarcoma, and reliable serum markers for sarcomas are lacking. To date, mass screening for uterine malignancies is not feasible or effective. PMID:22078749

  18. Histomorphological and Immunohistochemical Reappraisal of Cutaneous Adnexal Tumours: A Hospital Based Study

    PubMed Central

    Fatima, Uroos; Malaviya, Anil K.

    2016-01-01

    Background. Diagnosing adnexal tumours of the skin is a challenge due to their wide variety, infrequent occurrence in practice, and confusing morphological picture. Aims and Objectives. The present study aims to observe the spectrum of adnexal tumours at our institute and to evaluate them based on histomorphological, histochemical, and immunohistochemical methods either alone or in combination for proper identification and classification. Materials and Methods. A partly retrospective and partly prospective study was conducted on adnexal skin tumours over a period of 6 years. Relevant clinical profile was recorded. Histopathological examination was carried out and special stains were applied as and when required. Immunohistochemistry was performed where diagnosis with routine stains was not possible. Results. A total of 150 skin tumour biopsies were received. There were 87 keratotic tumours, 39 adnexal tumours, and 24 melanocytic tumours. Amongst the adnexal tumours, 51.3% eccrine, 30.8% follicular, and 17.9% sebaceous tumours were seen. In five cases, histological diagnosis was troublesome where immunohistochemistry helped in making final diagnosis. Limitations. The sample size is small. Conclusion. Histomorphology is confirmatory in majority of the adnexal tumours but few rare lesions that mimic internal malignancy require a panel of immunomarkers to rule out other possible differentials.

  19. Distant extradural haematoma complicating removal of frontal tumours.

    PubMed Central

    Sinar, E J; Lindsay, K W

    1986-01-01

    The authors report two patients who developed occipito-parietal extradural haematomas following removal of large frontal meningiomas. In both, CT scanning aided diagnosis and subsequent management. Although rare, this complication should be considered when patients deteriorate or fail to improve after removal of frontally situated tumours or inexplicable brain swelling is encountered at the time of original surgery. Images PMID:3701355

  20. Distant extradural haematoma complicating removal of frontal tumours.

    PubMed

    Sinar, E J; Lindsay, K W

    1986-04-01

    The authors report two patients who developed occipito-parietal extradural haematomas following removal of large frontal meningiomas. In both, CT scanning aided diagnosis and subsequent management. Although rare, this complication should be considered when patients deteriorate or fail to improve after removal of frontally situated tumours or inexplicable brain swelling is encountered at the time of original surgery. PMID:3701355

  1. Tumours of the spleen

    PubMed Central

    Giovagnoni, Andrea; Giorgi, Chiara; Goteri, Gaia

    2005-01-01

    The spleen has been considered a ‘forgotten organ’ even if it is included and well demonstrated on every CT and MRI of the abdomen. Tumours of the spleen are rare; however, radiologists need to be aware of the main tumoral features and patterns in order to try to distinguish between benign and malignant masses often discovered incidentally. The principal tumoral masses, benign (cysts, haemangiomas, litteral cell angioma, lymphangioma) and malignant (lymphoma, metastases haemagiosarcoma), are described. PMID:16154823

  2. Value of cytoprognostic classification in breast carcinomas.

    PubMed Central

    Mouriquand, J; Gozlan-Fior, M; Villemain, D; Bouchet, Y; Sage, J C; Mermet, M A; Bolla, M

    1986-01-01

    Two hundred and four cases of breast carcinoma were classified according to cytological features, and these were related to prognosis. A disease free interval of seven years was 95% for patients with grade I, 70% for those with grade II, and 45% for those with grade III tumours. The risk of recurrence was also related to tumour size and the presence or absence of steroid receptors in the tumour. Cytological classification of breast carcinoma based on fine needle aspiration provides valuable information concerning the prognosis of patients, which is relevant to their clinical management. Images PMID:3722403

  3. [Adrenal tumours in childhood].

    PubMed

    Martos-Moreno, G A; Pozo-Román, J; Argente, J

    2013-09-01

    This special article aims to summarise the current knowledge regarding the two groups of tumours with their origin in the adrenal gland: 1) adrenocortical tumours, derived from the cortex of the adrenal gland and 2) phaeochromocytomas and paragangliomas, neuroendocrine tumours derived from nodes of neural crest derived cells symmetrically distributed at both sides of the entire spine (paragangliomas [PG]). These PGs can be functioning tumors that secrete catecholamines, which confers their typical dark colour after staining with chromium salts (chromaffin tumors). Among these, the term phaeochromocytoma (PC) is restricted to those PGs derived from the chromaffin cells in the adrenal medulla (intra-adrenal PGs), whereas the term PG is used for those sympathetic or parasympathetic ones in an extra-adrenal location. We analyse the state of the art of their pathogenic and genetic bases, as well as their clinical signs and symptoms, the tests currently available for performing their diagnosis (biochemical, hormonal, imaging and molecular studies) and management (surgery, pre- and post-surgical medical treatment), considering the current and developing strategies in chemo- and radiotherapy. PMID:23796614

  4. Classification of binary intentions for individuals with impaired oculomotor function: ‘eyes-closed’ SSVEP-based brain-computer interface (BCI)

    NASA Astrophysics Data System (ADS)

    Lim, Jeong-Hwan; Hwang, Han-Jeong; Han, Chang-Hee; Jung, Ki-Young; Im, Chang-Hwan

    2013-04-01

    Objective. Some patients suffering from severe neuromuscular diseases have difficulty controlling not only their bodies but also their eyes. Since these patients have difficulty gazing at specific visual stimuli or keeping their eyes open for a long time, they are unable to use the typical steady-state visual evoked potential (SSVEP)-based brain-computer interface (BCI) systems. In this study, we introduce a new paradigm for SSVEP-based BCI, which can be potentially suitable for disabled individuals with impaired oculomotor function. Approach. The proposed electroencephalography (EEG)-based BCI system allows users to express their binary intentions without needing to open their eyes. A pair of glasses with two light emitting diodes flickering at different frequencies was used to present visual stimuli to participants with their eyes closed, and we classified the recorded EEG patterns in the online experiments conducted with five healthy participants and one patient with severe amyotrophic lateral sclerosis (ALS). Main results. Through offline experiments performed with 11 participants, we confirmed that human SSVEP could be modulated by visual selective attention to a specific light stimulus penetrating through the eyelids. Furthermore, the recorded EEG patterns could be classified with accuracy high enough for use in a practical BCI system. After customizing the parameters of the proposed SSVEP-based BCI paradigm based on the offline analysis results, binary intentions of five healthy participants were classified in real time. The average information transfer rate of our online experiments reached 10.83 bits min-1. A preliminary online experiment conducted with an ALS patient showed a classification accuracy of 80%. Significance. The results of our offline and online experiments demonstrated the feasibility of our proposed SSVEP-based BCI paradigm. It is expected that our ‘eyes-closed’ SSVEP-based BCI system can be potentially used for communication of disabled individuals with impaired oculomotor function.

  5. Maspin as a tumour suppressor in salivary gland tumour.

    PubMed

    Tarakji, Bassel; Ashok, Nipun; Sheirawan, Mohammad Kinan; Altamimi, Mohammed Alsakran; Alenzi, Faris; Azzeghaiby, Saleh Nasser; Baroudi, Kusai; Nassani, Mohammad Zakaria

    2014-12-01

    Maspin is a protein that belongs to serin protease inhibitor (serpin) superfamily. The purpose of this study was to review the literature concerning the expression of maspin in salivary gland tumours. A literature search was done using MEDLINE, accessed via the National Library of Medicine PubMed interface. Statistical analysis was not done because only seven studies were available in literature, the collected data were different and the results could not be compared. Expression of maspin was down regulated in more aggressive salivary gland tumours. Maspin may function as a tumour suppressor in salivary gland tumours. PMID:25654053

  6. Maspin as a Tumour Suppressor in Salivary Gland Tumour

    PubMed Central

    Ashok, Nipun; Sheirawan, Mohammad Kinan; Altamimi, Mohammed Alsakran; Alenzi, Faris; Azzeghaiby, Saleh Nasser; Baroudi, Kusai; Nassani, Mohammad Zakaria

    2014-01-01

    Maspin is a protein that belongs to serin protease inhibitor (serpin) superfamily. The purpose of this study was to review the literature concerning the expression of maspin in salivary gland tumours. A literature search was done using MEDLINE, accessed via the National Library of Medicine PubMed interface. Statistical analysis was not done because only seven studies were available in literature, the collected data were different and the results could not be compared. Expression of maspin was down regulated in more aggressive salivary gland tumours. Maspin may function as a tumour suppressor in salivary gland tumours. PMID:25654053

  7. Identification of genes involved in the biology of atypical teratoid/rhabdoid tumours using Drosophila melanogaster

    NASA Astrophysics Data System (ADS)

    Jeibmann, Astrid; Eikmeier, Kristin; Linge, Anna; Kool, Marcel; Koos, Björn; Schulz, Jacqueline; Albrecht, Stefanie; Bartelheim, Kerstin; Frühwald, Michael C.; Pfister, Stefan M.; Paulus, Werner; Hasselblatt, Martin

    2014-06-01

    Atypical teratoid/rhabdoid tumours (AT/RT) are malignant brain tumours. Unlike most other human brain tumours, AT/RT are characterized by inactivation of one single gene, SMARCB1. SMARCB1 is a member of the evolutionarily conserved SWI/SNF chromatin remodelling complex, which has an important role in the control of cell differentiation and proliferation. Little is known, however, about the pathways involved in the oncogenic effects of SMARCB1 inactivation, which might also represent targets for treatment. Here we report a comprehensive genetic screen in the fruit fly that revealed several genes not yet associated with loss of snr1, the Drosophila homologue of SMARCB1. We confirm the functional role of identified genes (including merlin, kibra and expanded, known to regulate hippo signalling pathway activity) in human rhabdoid tumour cell lines and AT/RT tumour samples. These results demonstrate that fly models can be employed for the identification of clinically relevant pathways in human cancer.

  8. Metabolic scaling in solid tumours

    NASA Astrophysics Data System (ADS)

    Milotti, E.; Vyshemirsky, V.; Sega, M.; Stella, S.; Chignola, R.

    2013-06-01

    Tumour metabolism is an outstanding topic of cancer research, as it determines the growth rate and the global activity of tumours. Recently, by combining the diffusion of oxygen, nutrients, and metabolites in the extracellular environment, and the internal motions that mix live and dead cells, we derived a growth law of solid tumours which is linked to parameters at the cellular level. Here we use this growth law to obtain a metabolic scaling law for solid tumours, which is obeyed by tumours of different histotypes both in vitro and in vivo, and we display its relation with the fractal dimension of the distribution of live cells in the tumour mass. The scaling behaviour is related to measurable parameters, with potential applications in the clinical practice.

  9. A short history of neuroendocrine tumours and their peptide hormones.

    PubMed

    de Herder, Wouter W; Rehfeld, Jens F; Kidd, Mark; Modlin, Irvin M

    2016-01-01

    The discovery of neuroendocrine tumours of the gastrointestinal tract and pancreas started in 1870, when Rudolf Heidenhain discovered the neuroendocrine cells, which can lead to the development of these tumours. Siegfried Oberndorfer was the first to introduce the term carcinoid in 1907. The pancreatic islet cells were first described in 1869 by Paul Langerhans. In 1924, Seale Harris was the first to describe endogenous hyperinsulinism/insulinoma. In 1942 William Becker and colleagues were the first to describe the glucagonoma syndrome. The first description of gastrinoma by Robert Zollinger and Edwin Ellison dates from 1955. The first description of the VIPoma syndrome by John Verner and Ashton Morrison dates from 1958. In 1977, the groups of Lars-Inge Larsson and Jens Rehfeld, and of Om Ganda reported the first cases of somatostatinoma. But only in 2013, Jens Rehfeld and colleagues described the CCK-oma syndrome. The most recently updated WHO classification for gastrointestinal neuroendocrine tumours dates from 2010. PMID:26971840

  10. Mesenchymal tumours of the bladder and prostate: an update.

    PubMed

    Tavora, Fabio; Kryvenko, Oleksandr N; Epstein, Jonathan I

    2013-02-01

    Mesenchymal tumours of the urinary bladder and prostate are infrequent neoplasms. The body of literature is growing with isolated case reports and short series, and the majority of cases are benign neoplasms. Other than stromal tumour of uncertain malignant potential and prostatic stromal sarcoma, both neoplasms derived from the specific prostatic stroma, the mesenchymal neoplasms in these locations are identical to their counterparts seen in other organs. However, the limited amount of tissue generated by biopsy and rarity of mesenchymal lesions in these sites create unique diagnostic difficulties, while correct classification of the neoplasm often bears significant impact on prognosis and therapeutic strategy. In this review we summarise the diagnostic features, focus on the differential diagnosis, and highlight the potential diagnostic pitfalls of mesenchymal tumours of the bladder and prostate. PMID:23250042

  11. Tumour budding: a promising parameter in colorectal cancer.

    PubMed

    Lugli, A; Karamitopoulou, E; Zlobec, I

    2012-05-22

    In 2011, the Tumour Node Metastasis (TNM) staging system still remains the gold standard for stratifying colorectal cancer (CRC) patients into prognostic subgroups, and is considered a solid basis for treatment management. Nevertheless, there is still a challenge with regard to therapeutic strategy; stage II patients are not typically selected for postoperative adjuvant chemotherapy, although some stage II patients have a comparable outcome to stage III patients who, themselves do receive such treatment. Consequently, there has been an inundation of 'prognostic biomarker' studies aiming to improve the prognostic stratification power of the TNM staging system. Most proposed biomarkers are not implemented because of lack of reproducibility, validation and standardisation. This problem can be partially resolved by following the REMARK guidelines. In search of novel prognostic factors for patients with CRC, one might glance at a table in the book entitled 'Prognostic Factors in Cancer' published by the International Union against Cancer (UICC) in 2006, in which TNM stage, L and V classifications are considered 'essential' prognostic factors, whereas tumour grade, perineural invasion, tumour budding and tumour-border configuration among others are proposed as 'additional' prognostic factors. Histopathology reports normally include the 'essential' features and are accompanied by tumour grade, histological subtype and information on perineural invasion, but interestingly, the tumour-border configuration (i.e., growth pattern) and especially tumour budding are rarely reported. Although scoring systems such as the 'BRE' in breast and 'Gleason' in prostate cancer are solidly based on histomorphological features and used in daily practice, no such additional scoring system to complement TNM staging is available for CRC. Regardless of differences in study design and methods for tumour-budding assessment, the prognostic power of tumour budding has been confirmed by dozens of study groups worldwide, suggesting that tumour budding may be a valuable candidate for inclusion into a future prognostic scoring system for CRC. This mini-review therefore attempts to present a short and concise overview on tumour budding, including morphological, molecular and prognostic aspects underlining its inter-disciplinary relevance. PMID:22531633

  12. Gastrointestinal endocrine tumours. Insulinoma.

    PubMed

    Grant, C S

    1996-12-01

    Fundamental to establishing a diagnosis of insulinoma is first to consider the diagnosis when presented with the constellation of symptoms and signs that indicate hypoglycaemia. Prominent and most convincing are manifestations of neuroglycopenia. Although hypoglycaemia can be caused by a number of disorders, the combination of hypoglycaemia and endogenous hyperinsulinaemia is diagnostic of insulinoma. Our criteria now include a glucose level of 40 mg/dl with a concomitant insulin level of 6 microU/ml, a C-peptide level exceeding 200 pmol/l, and negative screen for sulphonlyurea. Ancillary diagnostic tests or the use of insulin surrogates may offer helpful confirmation. Localization is still evolving, but in our hands pre-operative ultrasound is the best and only pre-operative test that we obtain in the usual situation. Expertise and experience with other modalities at other institutions offer reasonable but more costly alternatives. Intraoperative ultrasonography provides significant benefit in both tumour localization and delineating important related anatomy. Insulinomas are virtually all located in the pancreas; 90% are benign, single, and are generally firmer than surrounding normal pancreas. Extensive exposure may be required to identify and remove safely the tumour. Enucleation is our preferred technique, but distal pancreatectomy for tumours in the body or tail is an excellent method as well. Pancreatoduodenectomy is rarely necessary. Complications most commonly relate to leak of pancreatic secretions, causing pseudocyst, abscess, or fistula. except in MEN 1 syndrome, excision of a benign insulinoma equates with disease cure, and patients are often extraordinarily grateful as the change in their lives may be profound. PMID:9113316

  13. Tumour exosomes inhibit binding of tumour-reactive antibodies to tumour cells and reduce ADCC.

    PubMed

    Battke, Christina; Ruiss, Romana; Welsch, Ulrich; Wimberger, Pauline; Lang, Stephan; Jochum, Simon; Zeidler, Reinhard

    2011-05-01

    In order to grow within an immunocompetent host, tumour cells have evolved various strategies to cope with the host's immune system. These strategies include the downregulation of surface molecules and the secretion of immunosuppressive factors like IL-10 and PGE2 that impair the maturation of immune effector cells, among other mechanisms. Recently, tumour exosomes (TEX) have also been implicated in tumour-induced immune suppression as it has been shown that TEX can induce apoptosis in T lymphocytes. In this study, we extend our knowledge about immunosuppressive features of these microvesicles in that we show that TEX efficiently bind and sequester tumour-reactive antibodies and dramatically reduce their binding to tumour cells. Moreover, we demonstrate that this antibody sequestration reduces the antibody-dependent cytotoxicity by immune effector cells, which is among the most important anti-tumour reactions of the immune system and a significant activity of therapeutic antibodies. Taken together, these data point to the fact that tumour-derived exosomes interfere with the tumour-specific function of immune cells and constitute an additional mechanism how tumours escape from immune surveillance. PMID:21293856

  14. Peritoneal Tumours in Asbestosis

    PubMed Central

    Enticknap, J. B.; Smither, W. J.

    1964-01-01

    Eleven cases of diffuse abdominal tumours in association with exposure to asbestos were discovered in the years 1958 to 1963. There were eight men and three women, all of whom had worked at the same factory. In seven of the men the age at death ranged from 38 to 78 years; one man is still alive at the age of 46. The women died at 44, 61, and 67. The survival time after the first exposure varied from 20 to 46 years. The shortest period of exposure was 10 months and the longest 32 years. All three of the main commercial types of asbestos had been involved in their working operations. Histological confirmation of the nature of the tumour has been obtained at necropsy in nine of the 10 deceased and at biopsy in six, including the survivor. A remarkable feature of these cases is the minimal fibrosis found in the lungs. In three men and one woman, asbestosis was not diagnosed during life, and no patient was completely disabled by pulmonary fibrosis. Images PMID:14106131

  15. The prognostic significance of tumour cell proliferation in squamous cell carcinomas of the oesophagus.

    PubMed Central

    Sarbia, M.; Bittinger, F.; Porschen, R.; Dutkowski, P.; Torzewski, M.; Willers, R.; Gabbert, H. E.

    1996-01-01

    Tumour samples from 150 patients with squamous cell carcinoma of the oesophagus were investigated immunohistochemically with the monoclonal antibody MIB-1, which recognises proliferating cells. Using light microscopy, the number of MIB-1-positive tumour cells was counted in the areas with the highest proliferative activity. The MIB-1 index was determined as the proportion of MIB-1-positive and MIB-1-negative tumour cells. A considerable variation of the MIB-1 indices was found between the different tumours with a minimum of 6% and a maximum of 95% (median, 33%). The MIB-1 index correlated significantly with the mitotic activity in the tumour tissue (r = 0.33; P = 0.0001) and with the proportion of apoptotic tumour cells (r = 0.25; P = 0.0017). No significant correlation was found between the MIB-1 index and various other prognostic parameters including pT classification, pN classification, tumour grade, blood vessel invasion and lymphatic vessel invasion. In the univariate survival analysis no significant difference was found between tumours with low (< or = 33%) and high MIB-1 index (> 33%) 5-year survival rate: low MIB-1 index, 19.2%; high MIB-1 index, 22.2%). In a Cox proportional hazard regression analysis only the parameters lymphatic vessel invasion (P = 0.0001), pT classification (P = 0.0034) and pN classification (P = 0.0256), but not the MIB-1 index, could be verified as independent prognostic variables. In conclusion, evaluation of the MIB-1 index does not provide prognostic information for oesophageal cancer patients. Images Figure 1 PMID:8855967

  16. Tumours of the cauda equina.

    PubMed Central

    Fearnside, M R; Adams, C B

    1978-01-01

    A retrospective study of 70 consecutive patients with a cauda equina tumour who were admitted to Neurosurgical Department at the Radcliffe Infirmary, Oxford is presented. The diagnosis of these tumours is often difficult and delayed. The quality of life largely depends upon the neurological disability at presentation. The diagnostic features and investigations are discussed together with the treatment and prognosis. PMID:146075

  17. Aligning brains and minds

    PubMed Central

    Tong, Frank

    2012-01-01

    In this issue of Neuron, Haxby and colleagues describe a new method for aligning functional brain activity patterns across participants. Their study demonstrates that objects are similarly represented across different brains, allowing for reliable classification of one person’s brain activity based on another’s. PMID:22017984

  18. Adapting radiotherapy to hypoxic tumours

    NASA Astrophysics Data System (ADS)

    Malinen, Eirik; Søvik, Åste; Hristov, Dimitre; Bruland, Øyvind S.; Rune Olsen, Dag

    2006-10-01

    In the current work, the concepts of biologically adapted radiotherapy of hypoxic tumours in a framework encompassing functional tumour imaging, tumour control predictions, inverse treatment planning and intensity modulated radiotherapy (IMRT) were presented. Dynamic contrast enhanced magnetic resonance imaging (DCEMRI) of a spontaneous sarcoma in the nasal region of a dog was employed. The tracer concentration in the tumour was assumed related to the oxygen tension and compared to Eppendorf histograph measurements. Based on the pO2-related images derived from the MR analysis, the tumour was divided into four compartments by a segmentation procedure. DICOM structure sets for IMRT planning could be derived thereof. In order to display the possible advantages of non-uniform tumour doses, dose redistribution among the four tumour compartments was introduced. The dose redistribution was constrained by keeping the average dose to the tumour equal to a conventional target dose. The compartmental doses yielding optimum tumour control probability (TCP) were used as input in an inverse planning system, where the planning basis was the pO2-related tumour images from the MR analysis. Uniform (conventional) and non-uniform IMRT plans were scored both physically and biologically. The consequences of random and systematic errors in the compartmental images were evaluated. The normalized frequency distributions of the tracer concentration and the pO2 Eppendorf measurements were not significantly different. 28% of the tumour had, according to the MR analysis, pO2 values of less than 5 mm Hg. The optimum TCP following a non-uniform dose prescription was about four times higher than that following a uniform dose prescription. The non-uniform IMRT dose distribution resulting from the inverse planning gave a three times higher TCP than that of the uniform distribution. The TCP and the dose-based plan quality depended on IMRT parameters defined in the inverse planning procedure (fields and step-and-shoot intensity levels). Simulated random and systematic errors in the pO2-related images reduced the TCP for the non-uniform dose prescription. In conclusion, improved tumour control of hypoxic tumours by dose redistribution may be expected following hypoxia imaging, tumour control predictions, inverse treatment planning and IMRT.

  19. Deep neural network with weight sparsity control and pre-training extracts hierarchical features and enhances classification performance: Evidence from whole-brain resting-state functional connectivity patterns of schizophrenia.

    PubMed

    Kim, Junghoe; Calhoun, Vince D; Shim, Eunsoo; Lee, Jong-Hwan

    2016-01-01

    Functional connectivity (FC) patterns obtained from resting-state functional magnetic resonance imaging data are commonly employed to study neuropsychiatric conditions by using pattern classifiers such as the support vector machine (SVM). Meanwhile, a deep neural network (DNN) with multiple hidden layers has shown its ability to systematically extract lower-to-higher level information of image and speech data from lower-to-higher hidden layers, markedly enhancing classification accuracy. The objective of this study was to adopt the DNN for whole-brain resting-state FC pattern classification of schizophrenia (SZ) patients vs. healthy controls (HCs) and identification of aberrant FC patterns associated with SZ. We hypothesized that the lower-to-higher level features learned via the DNN would significantly enhance the classification accuracy, and proposed an adaptive learning algorithm to explicitly control the weight sparsity in each hidden layer via L1-norm regularization. Furthermore, the weights were initialized via stacked autoencoder based pre-training to further improve the classification performance. Classification accuracy was systematically evaluated as a function of (1) the number of hidden layers/nodes, (2) the use of L1-norm regularization, (3) the use of the pre-training, (4) the use of framewise displacement (FD) removal, and (5) the use of anatomical/functional parcellation. Using FC patterns from anatomically parcellated regions without FD removal, an error rate of 14.2% was achieved by employing three hidden layers and 50 hidden nodes with both L1-norm regularization and pre-training, which was substantially lower than the error rate from the SVM (22.3%). Moreover, the trained DNN weights (i.e., the learned features) were found to represent the hierarchical organization of aberrant FC patterns in SZ compared with HC. Specifically, pairs of nodes extracted from the lower hidden layer represented sparse FC patterns implicated in SZ, which was quantified by using kurtosis/modularity measures and features from the higher hidden layer showed holistic/global FC patterns differentiating SZ from HC. Our proposed schemes and reported findings attained by using the DNN classifier and whole-brain FC data suggest that such approaches show improved ability to learn hidden patterns in brain imaging data, which may be useful for developing diagnostic tools for SZ and other neuropsychiatric disorders and identifying associated aberrant FC patterns. PMID:25987366

  20. Staging of Klatskin tumours (hilar cholangiocarcinomas): comparison of MR cholangiography, MR imaging, and endoscopic retrograde cholangiography.

    PubMed

    Vogl, Thomas J; Schwarz, Wolfram O; Heller, Matthias; Herzog, Christopher; Zangos, Stephan; Hintze, Rainer E; Neuhaus, Peter; Hammerstingl, Renate M

    2006-10-01

    The aim of the study was to compare prospectively magnetic resonance cholangiography (MRC) and magnetic resonance imaging (MRI) with endoscopic retrograde cholangiography (ERC) in the diagnosis and staging of Klatskin tumours of the biliary tree (hilar cholangiocarcinomas). Forty-six patients with suspected Klatskin tumours of the biliary tract underwent MRI and heavily T2-weighted, non-breathhold, respiratory-triggered fast spin-echo MRC. Forty-two patients underwent ERC within 24 h; in four patients, ERC was not feasible, and percutaneous trans-hepatic cholangiography (PTC) was carried out instead. Two independent investigators evaluated imaging results for the presence of tumour, bile duct dilatation, and stenosis. Clinical and histopathological correlation revealed Klatskin tumours in 33 patients. MRI revealed a slightly hyperintense signal of infiltrated bile ducts in T2-weighted fast spin-echo sequences. The malignant lesion was regularly visualized as a hypointense area in T1-weighted gradient-echo sequences with substantial contrast enhancement along the involved bile duct walls. MRC revealed the location and extension of the tumour in 31 of 33 cases correctly (sensitivity 94%, specificity 100%, diagnostic accuracy 95%). In 27 of 31 cases, ERC enabled accurate staging and diagnosis of Klatskin tumours with a sensitivity of 87%. ERC and PTC combined yielded a sensitivity of 84% and a specificity of 97%. Tumours were grouped according to the Bismuth classification, with MRC allowing correct identification of type I tumour in seven patients, type II tumour in four patients, type III tumour in 12 patients, and type IV tumour in ten patients. MRC provided superior visualization of completely obstructed peripheral systems. MRC in combination with MRI is a reliable non-invasive diagnostic method for the pre-therapeutic staging of Klatskin tumours. PMID:16622690

  1. Primary neuroendocrine tumour of the breast: a case report and review of the literature

    PubMed Central

    Tato-Varela, Sara; Albalat-Fernández, Rosa; Pabón-Fernández, Sara; Zarco, Enrique Rodríguez; Calle-Marcos, Manolo La

    2015-01-01

    Primary neuroendocrine tumour of the breast is a rare entity that first appeared in the 2003 World Health Organisation (WHO) classification of breast tumours. The data currently available on its prognosis are contradictory, although it seems clear that histological varieties such as small cell neuroendocrine carcinoma have a worse prognosis, due to their low degree of differentiation. The treatment of choice is surgery, and the indications for chemotherapy or radiotherapy do not differ greatly from those used for other breast tumours. It is crucial to underline the difficulty of establishing treatment protocols due to the low incidence of this histological type. PMID:26798407

  2. Basaloid squamous cell carcinoma of the lung: a rare tumour with a rare clinical presentation.

    PubMed

    Cakir, Ebru; Demirag, Funda; Ucoluk, Gulnur Onde; Kaya, Sadi; Memis, Leyla

    2007-07-01

    Basaloid squamous cell carcinoma of the lung, an uncommon subtype of non-small cell carcinomas was introduced as a distinct entity in the recently revised World Health Organization (WHO) classification of lung tumours. This rare tumour most commonly develops in males older than 60 years. We report a 23-years-old female patient with basaloid squamous cell carcinoma of the lung who was stage IIB post-operatively. The patient is still alive and healthy 18 months after the operation. This is one of the youngest patient reported with this rare type of tumour. PMID:17328988

  3. Association of endodermal sinus tumour, testicular teratoma and alpha1-fetoprotein.

    PubMed Central

    Gariépy, G.; Lafortune, M.; Poisson, R.

    1976-01-01

    An endodermal sinus tumour in the retroperitoneal region was associated with the presence of alpha1-fetoprotein (AFP) in the patient's serum. At autopsy a simple cystic teratoma of the right testicle was also found. The association of these two tumours has been reported before. The classification of these malignant germ-cell tumours and an understanding of their evolution may be aided by the discovery that AFP is often found in the patient's serum. Images FIG. 1 FIG. 2 FIG. 3 FIG. 4 FIG. 5 FIG. 6 PMID:60168

  4. Suppression of putative tumour suppressor gene GLTSCR2 expression in human glioblastomas.

    PubMed

    Kim, Y-J; Cho, Y-E; Kim, Y-W; Kim, J-Y; Lee, S; Park, J-H

    2008-10-01

    Glioma tumour-suppressor candidate region gene 2 (GLTSCR2/PICT-1) is localized within the well-known 1.4 Mb tumour-suppressive region of chromosome 19q, which is frequently altered in various human tumours, including diffuse gliomas. Aside from its chromosomal localization, several lines of evidence, including PTEN-phosphorylating and cell-killing activities, suggests that GLTSCR2 participates in the suppression of tumour growth and development. However, little is known about the biological functions and molecular mechanisms of GLTSCR2 as a tumour suppressor gene. We investigated the pathological significance of GLTSCR2 expression in association with the development and progression of glioblastomas, the most common malignant brain tumour. We used real-time PCR and western blot analysis to examine the expression levels of GLTSCR2 mRNA and protein in glioblastomas, normal brain tissue and in non-glial tumour tissue of different origin, and found that GLTSCR2 expression is down-regulated in glioblastomas. In addition, direct sequencing analysis and fluorescence in situ hybridization clearly demonstrates the presence of genetic alterations, such as a nonsense mutation and deletion, in the GLTSCR2 gene in glioblastomas. Finally, our immunohistochemical study demonstrates that GLTSCR2 is sequentially down-regulated according to the histological malignant progression of the astrocytic glial tumour. Taken together, our results suggest that GLTSCR2 is involved in astrocytic glioma progression. PMID:18729076

  5. Effects of localised tumour hyperthermia on pimonidazole (Ro 03-8799) pharmacokinetics in mice.

    PubMed

    Walton, M I; Bleehen, N M; Workman, P

    1989-05-01

    We have investigated the effects of localised tumour hyperthermia (LTH; 43.5 degrees C x 30 min) on the acute toxicity and pharmacokinetics of the hypoxic cell sensitizer pimonidazole (Ro 03-8799) in mice. There were three treatment groups: unrestrained controls, sham-treated and LTH treated mice. LTH had minimal effects on the acute toxicity (LD50/7d) of pimonidazole with no significant difference between the three treatment groups. Pharmacokinetic studies were carried out at the maximum tolerated dose (MTD; approximately 60% LD50) of 437 micrograms g-1 i.v. in plasma, brain and tumour. Sham tumour treatment consistently increased plasma drug concentrations compared to unrestrained controls but had minimal effects on the elimination t1/2. The AUC0-infinitive was increased by 35% and the plasma clearance decreased by 26%. By contrast, LTH had minimal effects on these parameters compared to sham treatment. Brain pimonidazole concentrations were increased in restrained mice (sham and LTH treatments) compared to unrestrained controls, but average brain/plasma ratios were similar in all three groups at between 400 and 500%. Sham tumour treatment markedly reduced peak tumour pimonidazole concentrations compared to unrestrained controls giving a 29% lower AUC0-180min. Average tumour/plasma ratios were reduced from 236 to 129%. The most important finding was that LTH further reduced pimonidazole tumour concentrations, giving a 31% lower AUC0-180 min compared to sham treated tumours. Tumour/plasma ratios for pimonidazole were reduced by 41%. Plasma exposure to the pimonidazole N-oxide metabolite, Ro 31-0313, was unaltered by LTH. The markedly reduced drug concentrations in heated tumours may be a result of hyperthermia-stimulated bioreductive drug activation. PMID:2736198

  6. Recurrent hyperphosphatemic tumoural calcinosis

    PubMed Central

    Amit, Sonal; Agarwal, Asha; Nigam, Anand; Rao, Yashwant Kumar

    2012-01-01

    Tumoural calcinosis (TC) is a benign gradually developing disorder that can occur in a variety of clinical settings, characterised by subcutaneous deposition of calcium phosphate with or without giant cell reaction. We describe a case of 11-year-old girl presenting with recurrent hard swellings in the vicinity of shoulder and hip joints associated with elevated serum phosphate and normal serum calcium levels. TC has been mainly reported from Africa, with very few cases reported from India. After the diagnosis of hyperphosphatemic TC was established, the patient was treated with oral sevelamer and is under constant follow-up to detect recurrence, if any. The present case highlights the fact that although an uncommon lesion, TC must be considered in the differential diagnosis of subcutaneous hard lump in the vicinity of a joint. PMID:23010461

  7. Secondary penile tumours revisited

    PubMed Central

    Cherian, Jacob; Rajan, Sreekumar; Thwaini, Ali; Elmasry, Yaser; Shah, Tariq; Puri, Rajiv

    2006-01-01

    Objective To highlight the salient features of metastatic malignancies involving the penis, with special reference to the primary tumour sites, metastatic mechanisms, clinical features, differential diagnosis, treatment and prognosis. Methods A comprehensive search of the literature was performed using MEDLINE and EMBASE, using the keywords 'penis', 'secondary malignancy', 'metastasis' and 'malignant priapism' to identify reviews and case reports of secondary penile malignancy. A case of rare clinical presentation of metastatic penile lesion is presented along with the review of the literature. Conclusion Secondary malignancy of the penis is a rare clinical entity, despite the rich vascularisation of this organ. The majority of metastatic lesions take their origin from the neighbouring genito-urinary organs, mainly prostate and bladder. These lesions are often associated with disseminated malignancy and hence have a poor outcome. Nodular or ulcerative lesions involving the corpora cavernosa or priapism are the main modes of clinical presentation. In most cases, only palliative or supportive therapy is indicated. PMID:17032461

  8. Map Classification

    ERIC Educational Resources Information Center

    Larsgaard, Mary

    1973-01-01

    Although map classification may seem a somewhat esoteric subject, at least to those who are not map librarians, the enterprising searcher for map classification schemes can find a goodly number from which to choose. (30 references) (Author)

  9. JC polyomavirus in the aetiology and pathophysiology of glial tumours.

    PubMed

    Eftimov, Tihomir; Enchev, Yavor; Tsekov, Iliya; Simeonov, Plamen; Kalvatchev, Zlatko; Encheva, Elitsa

    2016-01-01

    Glial brain tumours with their poor prognosis, limited treatment modalities and unclear detailed pathophysiology represent a significant health concern. The purpose of the current study was to investigate and describe the possible role of the human polyomavirus JC as an underlying cancerogenic or co-cancerogenic factor in the complex processes of glial tumour induction and development. Samples from 101 patients with glial tumours were obtained during neurosurgical tumour resection. Small tissue pieces were taken from several areas of the histologically verified solid tumour core. Biopsies were used for DNA extraction and subsequent amplification reactions of sequences from the JC viral genome. Real-time polymerase chain reaction was used for detection and quantification of its non-coding control region (NCCR) and gene encoding the regulatory protein Large T antigen (LT). An average of 37.6 % of all patients was found to be LT positive, whereas only 6.9 % tested positive for NCCR. The analysis of the results demonstrated significant variance between the determined LT prevalence and the rate for NCCR, with a low starting copy number in all positive samples and threshold cycles in the range of 36 to 42 representing viral load in the range from 10 to 1000 copies/?l. The results most probably indicate incomplete JC viral replication. Under such conditions, mutations in the host cell genome may be accumulated due to interference of the virus with the host cell machinery, and eventually malignant transformation may occur. PMID:26560882

  10. Targeting the erythropoietin receptor on glioma cells reduces tumour growth

    SciTech Connect

    Peres, Elodie A.; Valable, Samuel; Guillamo, Jean-Sebastien; Departement de Neurologie, CHU de Caen ; Marteau, Lena; Bernaudin, Jean-Francois; Roussel, Simon; Lechapt-Zalcman, Emmanuele; Service d'Anatomie Pathologique, CHU de Caen ; Bernaudin, Myriam; Petit, Edwige

    2011-10-01

    Hypoxia has been shown to be one of the major events involved in EPO expression. Accordingly, EPO might be expressed by cerebral neoplastic cells, especially in glioblastoma, known to be highly hypoxic tumours. The expression of EPOR has been described in glioma cells. However, data from the literature remain descriptive and controversial. On the basis of an endogenous source of EPO in the brain, we have focused on a potential role of EPOR in brain tumour growth. In the present study, with complementary approaches to target EPO/EPOR signalling, we demonstrate the presence of a functional EPO/EPOR system on glioma cells leading to the activation of the ERK pathway. This EPO/EPOR system is involved in glioma cell proliferation in vitro. In vivo, we show that the down-regulation of EPOR expression on glioma cells reduces tumour growth and enhances animal survival. Our results support the hypothesis that EPOR signalling in tumour cells is involved in the control of glioma growth.

  11. Intra-tumoural microvessel density in human solid tumours

    PubMed Central

    Hasan, J; Byers, R; Jayson, G C

    2002-01-01

    Over the last decade assessment of angiogenesis has emerged as a potentially useful biological prognostic and predictive factor in human solid tumours. With the development of highly specific endothelial markers that can be assessed in histological archival specimens, several quantitative studies have been performed in various solid tumours. The majority of published studies have shown a positive correlation between intra-tumoural microvessel density, a measure of tumour angiogenesis, and prognosis in solid tumours. A minority of studies have not demonstrated an association and this may be attributed to significant differences in the methodologies employed for sample selection, immunostaining techniques, vessel counting and statistical analysis, although a number of biological differences may account for the discrepancy. In this review we evaluate the quantification of angiogenesis by immunohistochemistry, the relationship between tumour vascularity and metastasis, and the clinicopathological studies correlating intra-tumoral microvessel density with prognosis and response to anti-cancer therapy. In view of the extensive nature of this retrospective body of data, comparative studies are needed to identify the optimum technique and endothelial antigens (activated or pan-endothelial antigens) but subsequently prospective studies that allocate treatment on the basis of microvessel density are required. British Journal of Cancer (2002) 86, 1566–1577. DOI: 10.1038/sj/bjc/6600315 www.bjcancer.com © 2002 Cancer Research UK PMID:12085206

  12. A rare benign ovarian tumour.

    PubMed

    Morna Palmeiro, Marta; Cunha, Teresa Margarida; Loureiro, Ana Luisa; Esteves, Gonçalo

    2016-01-01

    Sclerosing stromal tumour (SST) of the ovary is an extremely rare and benign ovarian neoplasm, accounting for 6% of the sex cord stromal ovarian tumours subtype. Usually, it is found during the second and third decades of life. Patients commonly present with pelvic pain, a palpable pelvic mass or menstrual irregularity. We report a case of a 20-year-old woman reporting of mild pelvic pain, with normal laboratory data. On imaging examinations, a large right adnexal tumour was found, with features suggesting an ovarian sex cord tumour. The patient underwent right salpingo-oophorectomy, diagnosing a SST of the ovary. This paper also reviews the literature, and emphasises the typical pathological and imaging characteristics of these rare benign ovarian lesions, and their impact, in a conservative surgery. PMID:26933186

  13. [Malignant tumours of the hand].

    PubMed

    Knudsen, Britt Mejer; Rasmussen, Per Joen Svabo; Lausten, Gunnar Schwarz; Jensen, Nina Vendel; Søe, Niels Henrik

    2011-05-30

    Malignant tumours of the hand are rare and are often misdiagnosed. A painful swelling of the hand or digits are often diagnosed with an infection, benign tumours such as ganglion cysts, or arthritis. Wounds that do not heal despite adequate treatment should be biopsied to rule out malignancy. A correct diagnosis without delay is important because the life expectancy, due to a metastasis on the hand or fingers is approximately six months. PMID:21627901

  14. Therapy-induced tumour secretomes promote resistance and tumour progression

    PubMed Central

    Obenauf, Anna C.; Zou, Yilong; Ji, Andrew L.; Vanharanta, Sakari; Shu, Weiping; Shi, Hubing; Kong, Xiangju; Bosenberg, Marcus C.; Wiesner, Thomas; Rosen, Neal; Lo, Roger S.; Massagué, Joan

    2015-01-01

    Drug resistance invariably limits the clinical efficacy of targeted therapy with kinase inhibitors against cancer1,2. Here we show that targeted therapy with BRAF, ALK, or EGFR kinase inhibitors induces a complex network of secreted signals in drug-stressed melanoma and lung adenocarcinoma cells. This therapy-induced secretome (TIS) stimulates the outgrowth, dissemination, and metastasis of drug-resistant cancer cell clones and supports the survival of drug-sensitive cancer cells, contributing to incomplete tumour regression. The vemurafenib reactive secretome in melanoma is driven by down-regulation of the transcription factor FRA1. In situ transcriptome analysis of drug-resistant melanoma cells responding to the regressing tumour microenvironment revealed hyperactivation of multiple signalling pathways, most prominently the AKT pathway. Dual inhibition of RAF and PI3K/AKT/mTOR pathways blunted the outgrowth of the drug-resistant cell population in BRAF mutant melanoma tumours, suggesting this combination therapy as a strategy against tumour relapse. Thus, therapeutic inhibition of oncogenic drivers induces vast secretome changes in drug-sensitive cancer cells, paradoxically establishing a tumour microenvironment that supports the expansion of drug-resistant clones, but is susceptible to combination therapy. PMID:25807485

  15. Multiple tumours in survival estimates.

    PubMed

    Rosso, Stefano; De Angelis, Roberta; Ciccolallo, Laura; Carrani, Eugenio; Soerjomataram, Isabelle; Grande, Enrico; Zigon, Giulia; Brenner, Hermann

    2009-04-01

    In international comparisons of cancer registry based survival it is common practice to restrict the analysis to first primary tumours and exclude multiple cancers. The probability of correctly detecting subsequent cancers depends on the registry's running time, which results in different proportions of excluded patients and may lead to biased comparisons. We evaluated the impact on the age-standardised relative survival estimates of also including multiple primary tumours. Data from 2,919,023 malignant cancers from 69 European cancer registries participating in the EUROCARE-4 collaborative study were used. A total of 183,683 multiple primary tumours were found, with an overall proportion of 6.3% over all the considered cancers, ranging from 0.4% (Naples, Italy) to 12.9% (Iceland). The proportion of multiple tumours varied greatly by type of tumour, being higher for those with high incidence and long survival (breast, prostate and colon-rectum). Five-year relative survival was lower when including patients with multiple cancers. For all cancers combined the average difference was -0.4 percentage points in women and -0.7 percentage points in men, and was greater for older registries. Inclusion of multiple tumours led to lower survival in 44 out of 45 cancer sites analysed, with the greatest differences found for larynx (-1.9%), oropharynx (-1.5%), and penis (-1.3%). Including multiple primary tumours in survival estimates for international comparison is advisable because it reduces the bias due to different observation periods, age, registration quality and completeness of registration. The general effect of inclusion is to reduce survival estimates by a variable amount depending on the proportion of multiple primaries and cancer site. PMID:19121933

  16. Swiss Feline Cancer Registry: A Retrospective Study of the Occurrence of Tumours in Cats in Switzerland from 1965 to 2008.

    PubMed

    Graf, R; Grüntzig, K; Hässig, M; Axhausen, K W; Fabrikant, S; Welle, M; Meier, D; Guscetti, F; Folkers, G; Otto, V; Pospischil, A

    2015-11-01

    Cancer is one of the leading causes of death in companion animals. Information on the epidemiology of cancer is instrumental for veterinary practitioners in patient management; however, spontaneously arising tumours in companion animals also resemble those in man and can provide useful data in combating cancer. Veterinary cancer registries for cats are few in number and have often remained short-lived. This paper presents a retrospective study of tumours in cats in Switzerland from 1965 to 2008. Tumour diagnoses were coded according to topographical and morphological keys of the International Classification of Oncology for Humans (ICD-O-3). Correlations between breed, sex and age were then examined using a multiple logistic regression model. A total of 18,375 tumours were diagnosed in 51,322 cats. Of these, 14,759 (80.3%) tumours were malignant. Several breeds had significantly lower odds ratios for developing a tumour compared with European shorthair cats. The odds of a cat developing a tumour increased with age, up to the age of 16 years, and female cats had higher risk of developing a tumour compared with male cats. Skin (4,970; 27.05%) was the most frequent location for tumours, followed by connective tissue (3,498; 19.04%), unknown location (2,532; 13.78%) and female sexual organs (1,564; 8.51%). The most common tumour types were epithelial tumours (7,913; 43.06%), mesenchymal tumours (5,142; 27.98%) and lymphoid tumours (3,911; 21.28%). PMID:26422414

  17. Novel somatic and germline mutations in intracranial germ cell tumours.

    PubMed

    Wang, Linghua; Yamaguchi, Shigeru; Burstein, Matthew D; Terashima, Keita; Chang, Kyle; Ng, Ho-Keung; Nakamura, Hideo; He, Zongxiao; Doddapaneni, Harshavardhan; Lewis, Lora; Wang, Mark; Suzuki, Tomonari; Nishikawa, Ryo; Natsume, Atsushi; Terasaka, Shunsuke; Dauser, Robert; Whitehead, William; Adekunle, Adesina; Sun, Jiayi; Qiao, Yi; Marth, Gábor; Muzny, Donna M; Gibbs, Richard A; Leal, Suzanne M; Wheeler, David A; Lau, Ching C

    2014-07-10

    Intracranial germ cell tumours (IGCTs) are a group of rare heterogeneous brain tumours that are clinically and histologically similar to the more common gonadal GCTs. IGCTs show great variation in their geographical and gender distribution, histological composition and treatment outcomes. The incidence of IGCTs is historically five- to eightfold greater in Japan and other East Asian countries than in Western countries, with peak incidence near the time of puberty. About half of the tumours are located in the pineal region. The male-to-female incidence ratio is approximately 3-4:1 overall, but is even higher for tumours located in the pineal region. Owing to the scarcity of tumour specimens available for research, little is currently known about this rare disease. Here we report the analysis of 62 cases by next-generation sequencing, single nucleotide polymorphism array and expression array. We find the KIT/RAS signalling pathway frequently mutated in more than 50% of IGCTs, including novel recurrent somatic mutations in KIT, its downstream mediators KRAS and NRAS, and its negative regulator CBL. Novel somatic alterations in the AKT/mTOR pathway included copy number gains of the AKT1 locus at 14q32.33 in 19% of patients, with corresponding upregulation of AKT1 expression. We identified loss-of-function mutations in BCORL1, a transcriptional co-repressor and tumour suppressor. We report significant enrichment of novel and rare germline variants in JMJD1C, which codes for a histone demethylase and is a coactivator of the androgen receptor, among Japanese IGCT patients. This study establishes a molecular foundation for understanding the biology of IGCTs and suggests potentially promising therapeutic strategies focusing on the inhibition of KIT/RAS activation and the AKT1/mTOR pathway. PMID:24896186

  18. [Latest advances in pancreatic tumours].

    PubMed

    Lariño Noia, José

    2015-09-01

    Pancreatic cancer continues to have an extremely poor prognosis. There have been hardly any therapeutic advances in the last few years and consequently attention is focussed on early diagnosis. In this regard, endoscopic ultrasonography and several associated techniques, such as electrography or the use of intravenous contrast agents, continue to be the cornerstone of differential diagnosis. In the latest Digestive Diseases Week, numerous presentations were made on cystic pancreatic tumours, especially intraductal papillary mucinous tumours, with their well-known potential for malignant transformation. In addition to the problems of the preoperative characterization of these entities, by both endoscopic ultrasound cytological evaluation--even with the presence of an on-site pathologist--and by intracystic markers, the role of other techniques was also mentioned, such as confocal laser endomicroscopy or the use of intravenous contrast agents to characterize the wall nodule. There were numerous studies on the natural history of intraductal papillary mucinous tumours, which mainly supported the increasingly conservative approach adopted by the recent Fukuoka international guidelines. Certain aspects were highlighted, such as comorbidities, when considering surgery, or the growth rate of the tumour. In treatment, endoscopic ultrasound-guided injection of gemcitabine and paclitaxel, without the need for alcohol as an ablative treatment of mucinous cystic tumours, is gaining ground in specific cases. PMID:26520202

  19. Target classification strategies

    NASA Astrophysics Data System (ADS)

    Schachter, Bruce J.

    2015-05-01

    Target classification algorithms have generally kept pace with developments in the academic and commercial sectors since the 1970s. However, most recently, investment into object classification by internet companies and various Human Brain Projects have far outpaced that of the defense sector. Implications are noteworthy. There are some unique characteristics of the military classification problem. Target classification is not solely an algorithm design problem, but is part of a larger system design task. The design flows down from a concept of operations (ConOps) and key performance parameters (KPPs). Inputs are image and/or signal data and time-synchronized metadata. The operation is real-time. The implementation minimizes size, weight and power (SWaP). The output must be conveyed to a time-strapped operator who understands the rules of engagement. It is assumed that the adversary is actively trying to defeat recognition. The target list is often mission dependent, not necessarily a closed set, and may change on a daily basis. It is highly desirable to obtain sufficiently comprehensive training and testing data sets, but costs of doing so are very high and data on certain target types are scarce. The training data may not be representative of battlefield conditions suggesting the avoidance of highly tuned designs. A number of traditional and emerging target classification strategies are reviewed in the context of the military target problem.

  20. Tumour-associated eosinophilia: a review.

    PubMed Central

    Lowe, D; Jorizzo, J; Hutt, M S

    1981-01-01

    In a recent study of cervical carcinoma, 13 cases with a marked eosinophil infiltrate around the tumour were found. The histological appearance of the tumours was distinctive and suggested a specific response, similar to the lymphocyte infiltration in medullary carcinoma of the breast and seminoma. A review of published reports shows that tumour-associated tissue eosinophilia (TATE) and tumour-associated blood eosinophilia (TABE) may be seen in tumours of different histological types from different anatomical sites, and may occur together or separately. Tumours with TATE alone appear to have a better prognosis that those without, while TABE is associated with tumor spread and a poor prognosis. Images PMID:7035499

  1. Canine mammary mixed tumours: a review.

    PubMed

    Dantas Cassali, Geovanni; Cavalheiro Bertagnolli, Angélica; Ferreira, Enio; Araújo Damasceno, Karine; de Oliveira Gamba, Conrado; Bonolo de Campos, Cecília

    2012-01-01

    Mammary mixed tumours are the most frequent neoplasias in female dogs. In humans, mixed tumours are frequently found in the salivary glands and are known as pleomorphic adenomas. In addition to their histomorphologic similarities, mixed tumours and pleomorphic adenomas have the potential to become malignant and give rise to carcinomas in mixed tumours and carcinomas ex-pleomorphic adenoma, respectively. The factors associated with malignant transformation are still poorly known in the case of canine mixed tumours. However, this form of neoplasia tends to be associated with a better prognosis than other malignant histological types. This paper discusses the main features associated with female canine mammary mixed tumours. PMID:23193497

  2. Canine Mammary Mixed Tumours: A Review

    PubMed Central

    Dantas Cassali, Geovanni; Cavalheiro Bertagnolli, Angélica; Ferreira, Enio; Araújo Damasceno, Karine; de Oliveira Gamba, Conrado; Bonolo de Campos, Cecília

    2012-01-01

    Mammary mixed tumours are the most frequent neoplasias in female dogs. In humans, mixed tumours are frequently found in the salivary glands and are known as pleomorphic adenomas. In addition to their histomorphologic similarities, mixed tumours and pleomorphic adenomas have the potential to become malignant and give rise to carcinomas in mixed tumours and carcinomas ex-pleomorphic adenoma, respectively. The factors associated with malignant transformation are still poorly known in the case of canine mixed tumours. However, this form of neoplasia tends to be associated with a better prognosis than other malignant histological types. This paper discusses the main features associated with female canine mammary mixed tumours. PMID:23193497

  3. meso-Tetra(hydroxyphenyl)porphyrins, a new class of potent tumour photosensitisers with favourable selectivity.

    PubMed Central

    Berenbaum, M. C.; Akande, S. L.; Bonnett, R.; Kaur, H.; Ioannou, S.; White, R. D.; Winfield, U. J.

    1986-01-01

    We compared para-, meta- and ortho-isomers of meso-tetra(hydroxyphenyl)porphyrin (p-, m- and o-THPP) and the potassium salt of the para compound (K-p-THPP) with haematoporphyrin derivative (HpD) and Photofrin II in their ability to sensitise tumours, skin and brain to light. HpD and Photofrin II induced modest tumour photosensitisation at the cost of substantial skin and brain sensitisation. At doses low enough to keep sensitisation of these normal tissues within acceptable limits, tumour sensitisation was sufficient to give necrosis only approximately 2 mm deep after exposure to 10 J cm-2 light. In contrast, doses of p-THPP, K-p-THPP and m-THPP that produced skin and brain sensitivity within acceptable limits sensitised tumours enough to give 4-9 mm necrosis after 10 J cm-2 light. m-THPP was, on a molar basis, about 25-30 times as potent as HpD and Photofrin II in sensitising tumours. o-THPP was also a potent tumour photosensitiser, but induced a prohibitive degree of skin photosensitivity even at low doses. It is unlikely that these differences in relative selectivity are due to differences in such photophysical parameters as optimum activating wavelength (which would affect tissue penetration by light), or light absorption, and physicochemical factors that determine tissue localisation may be involved. The high tumour sensitising potency and favourable tissue selectivity of m-THPP, p-THPP and K-p-THPP make them promising candidates for clinical tumour phototherapy. PMID:2948536

  4. Tumour markers in breast cancer.

    PubMed Central

    Cove, D. H.; Woods, K. L.; Smith, S. C.; Burnett, D.; Leonard, J.; Grieve, R. J.; Howell, A.

    1979-01-01

    The clinical usefulness of 8 potential tumour markers has been evaluated in 69 patients with Stage I and II breast cancer and 57 patients with Stage III and IV. Serum CEA concentrations were raised in 13% of patients with local and 65% of those with advanced breast cancer. In patients with clinical evidence of progression or regression of tumour, serum CEA levels changed appropriately in 83% of cases. Taking 4 of the markers (carcinoembryonic antigen (CEA), lactalbumin, alpha subunit and haptoglobin) serum concentrations of one or more were raised in 33% of patients with local disease and 81% of those with advanced breast cancer. However, marker concentrations were often only marginally raised, and are unlikely to provide sensitive guide to tumour burden. CEA, lactalbumin and alpha subunit were detectable in 68%, 43% and 40% respectively of extracts of primary breast cancers. PMID:92331

  5. Tumour suppressor TRIM33 targets nuclear ?-catenin degradation

    PubMed Central

    Xue, Jianfei; Chen, Yaohui; Wu, Yamei; Wang, Zhongyong; Zhou, Aidong; Zhang, Sicong; Lin, Kangyu; Aldape, Kenneth; Majumder, Sadhan; Lu, Zhimin; Huang, Suyun

    2014-01-01

    Aberrant activation of ?-catenin in the nucleus has been implicated in a variety of human cancers but the fate of nuclear ?-catenin is unknown. Here we demonstrate that tripartite motif-containing protein 33 (TRIM33), acting as an E3 ubiquitin ligase, reduces the abundance of nuclear ?-catenin protein. TRIM33-mediated ?-catenin is destabilized and is GSK-3? or ?-TrCP independent. TRIM33 interacts with and ubiquitylates nuclear ?-catenin. Moreover, protein kinase C?, which directly phosphorylates ?-catenin at Ser715, is required for the TRIM33–?-catenin interaction. The function of TRIM33 in suppressing tumour cell proliferation and brain tumour development depends on TRIM33-promoted ?-catenin degradation. In human glioblastoma specimens, endogenous TRIM33 levels are inversely correlated with ?-catenin. In summary, our findings identify TRIM33 as a tumour suppressor that can abolish tumour cell proliferation and tumorigenesis by degrading nuclear ?-catenin. This work suggests a new therapeutic strategy against human cancers caused by aberrant activation of ?-catenin. PMID:25639486

  6. Maintaining Tumour Heterogeneity in Patient-Derived Tumour Xenografts

    PubMed Central

    Cassidy, John W; Caldas, Carlos; Bruna, Alejandra

    2015-01-01

    Pre-clinical models often fail to capture the diverse heterogeneity of human malignancies and as such lack clinical predictive power. Patient-derived tumour xenografts (PDXs) have emerged as a powerful technology: capable of retaining the molecular heterogeneity of their originating sample. However, heterogeneity within a tumour is governed by both cell-autonomous (e.g. genetic and epigenetic heterogeneity) and non-cell-autonomous (e.g. stromal heterogeneity) drivers. Whilst PDXs can largely recapitulate the polygenomic architecture of human tumours, they do not fully account for heterogeneity in the tumour microenvironment. Hence, these models have substantial utility in basic and translational research in cancer biology; but study of stromal or immune drivers of malignant progression may be limited. Similarly, PDX models offer the ability to conduct patient specific in vivo and ex vivo drug screens, but stromal contributions to treatment responses may be under-represented. This review discusses the sources and consequences of intratumour heterogeneity and how these are recapitulated in the PDX model. Limitations of the current generation of PDXs are discussed and strategies to improve several aspects of the model with respect to preserving heterogeneity are proposed. PMID:26180079

  7. Metastatic angiosarcoma: a vascular tumour or an intracranial haemorrhage?

    PubMed

    Masih, Izhaq; McIlwaine, Werner

    2010-01-01

    A 64-year-old man presented with weakness of his right arm and leg. He had previously had mitral valve replacement, tricuspid annuloplasty, leg deep vein thrombosis (DVT) and femoral embolism. Computed tomography (CT) scan of the brain showed an acute left thalamic haemorrhage. Repeat CT brain showed resolution of the original haemorrhage, but the apparent development of new areas of haemorrhage. Warfarin continued due to high risk of thromboembolism. He was readmitted with the rapid development of a visible swelling at the sternum and on the scalp. Ultrasound scan of the sternum revealed a vascular tumour. Suspected haemorrhages in the past were reported as the metastatic deposits. Biopsy and immunohistochemical staining confirmed angiosarcoma of the scalp. Being vascular tumours, angiosarcoma can mimic a brain haemorrhage. Our case illustrates a clinical conundrum. Diagnosing metastatic angiosarcoma of the brain proved difficult without visible primary and histology. The rapid clinical course of the disease and problems with anticoagulation therapy made treatment options limited and the prognosis worse. PMID:22736558

  8. [The probability of developing brain tumours among users of cellular telephones (scientific information to the decision of the International Agency for Research on Cancer (IARC) announced on May 31, 2011)].

    PubMed

    Grigor'ev, Iu G

    2011-01-01

    The WHO's International Agency for Research on Cancer (IARC) has made May 31 2011 PRESS RELEASE No 208 which classifies radiofrequency electromagnetic fields as possibly carcinogenic to humans (Group 2B). The decision is based on an increased risk of glioma, i.e., a malignant type of brain cancer associated with the wireless phone use. This paper reports the analysis of the long-term research on the issue in question that had been carried out in many countries around the world before the decision was made. PMID:22279776

  9. Imaging biomarkers of angiogenesis and the microvascular environment in cerebral tumours

    PubMed Central

    Thompson, G; Mills, S J; Coope, D J; O’connor, J P B; Jackson, A

    2011-01-01

    Conventional contrast-enhanced CT and MRI are now in routine clinical use for the diagnosis, treatment and monitoring of diseases in the brain. The presence of contrast enhancement is a proxy for the pathological changes that occur in the normally highly regulated brain vasculature and blood-brain barrier. With recognition of the limitations of these techniques, and a greater appreciation for the nuanced mechanisms of microvascular change in a variety of pathological processes, novel techniques are under investigation for their utility in further interrogating the microvasculature of the brain. This is particularly important in tumours, where the reliance on angiogenesis (new vessel formation) is crucial for tumour growth, and the resulting microvascular configuration and derangement has profound implications for diagnosis, treatment and monitoring. In addition, novel therapeutic approaches that seek to directly modify the microvasculature require more sensitive and specific biological markers of baseline tumour behaviour and response. The currently used imaging biomarkers of angiogenesis and brain tumour microvascular environment are reviewed. PMID:22433824

  10. Tumour vasculature--a potential therapeutic target.

    PubMed Central

    Baillie, C. T.; Winslet, M. C.; Bradley, N. J.

    1995-01-01

    The tumour vasculature is vital for the establishment, growth and metastasis of solid tumours. Its physiological properties limit the effectiveness of conventional anti-cancer strategies. Therapeutic approaches directed at the tumour vasculature are reviewed, suggesting the potential of anti-angiogenesis and the targeting of vascular proliferation antigens as cancer treatments. PMID:7543770

  11. Classification Accuracy of Serum Apo A-I and S100B for the Diagnosis of Mild Traumatic Brain Injury and Prediction of Abnormal Initial Head Computed Tomography Scan

    PubMed Central

    Blyth, Brian J.; He, Hua; Mookerjee, Sohug; Jones, Courtney; Kiechle, Karin; Moynihan, Ryan; Wojcik, Susan M.; Grant, William D.; Secreti, LaLainia M.; Triner, Wayne; Moscati, Ronald; Leinhart, August; Ellis, George L.; Khan, Jawwad

    2013-01-01

    Abstract The objective of the current study was to determine the classification accuracy of serum S100B and apolipoprotein (apoA-I) for mild traumatic brain injury (mTBI) and abnormal initial head computed tomography (CT) scan, and to identify ethnic, racial, age, and sex variation in classification accuracy. We performed a prospective, multi-centered study of 787 patients with mTBI who presented to the emergency department within 6?h of injury and 467 controls who presented to the outpatient laboratory for routine blood work. Serum was analyzed for S100B and apoA-I. The outcomes were disease status (mTBI or control) and initial head CT scan. At cutoff values defined by 90% of controls, the specificity for mTBI using S100B (0.899 [95% confidence interval (CI): 0.78–0.92]) was similar to that using apoA-I (0.902 [0.87–0.93]), and the sensitivity using S100B (0.252 [0.22–0.28]) was similar to that using apoA-I (0.249 [0.22–0.28]). The area under the receiver operating characteristic curve (AUC) for the combination of S100B and apoA-I (0.738, 95% CI: 0.71, 0.77), however, was significantly higher than the AUC for S100B alone (0.709, 95% CI: 0.68, 0.74, p=0.001) and higher than the AUC for apoA-I alone (0.645, 95% CI: 0.61, 0.68, p<0.0001). The AUC for prediction of abnormal initial head CT scan using S100B was 0.694 (95%CI: 0.62, 0.77) and not significant for apoA-I. At a S100B cutoff of <0.060??g/L, the sensitivity for abnormal head CT was 98%, and 22.9% of CT scans could have been avoided. There was significant age and race-related variation in the accuracy of S100B for the diagnosis of mTBI. The combined use of serum S100B and apoA-I maximizes classification accuracy for mTBI, but only S100B is needed to classify abnormal head CT scan. Because of significant subgroup variation in classification accuracy, age and race need to be considered when using S100B to classify subjects for mTBI. PMID:23758329

  12. Immunohistochemical study of granular cell tumours. Demonstration of neurone specific enolase, S 100 protein, laminin and alpha-1-antichymotrypsin.

    PubMed

    Nathrath, W B; Remberger, K

    1986-01-01

    Nine granular cell tumours were investigated with poly- or monoclonal antisera to neurone specific enolase (NSE), glial enolase (GE), S 100 protein, alpha-1-antichymotrypsin, lysozyme, laminin, neurofilament (NF), glial fibrillary acidic protein (GFAP), brain creatine kinase (CK), different cytokeratins (Keratin Dako, PKK1), tissue polypeptide antigen (TPA), carcinoembryonic antigen (CEA), desmin, myoglobin and leukocyte common antigen (LCA), using immunoperoxidase-methods on formalin fixed paraffin embedded sections. While five tumours from adults show specific cytoplasmic staining for NSE and S 100, three congenital tumours, two from the gingiva and one from palatine, show only a weak reaction for NSE, reflecting a possible origin from mature and immature Schwann cells, respectively. However, one subcutaneous tumour from near the clavicule of a ten year old girl differs from the other eight tumours by its specific cytoplasmic staining for alpha-1-antichymotrypsin only, supporting the view that there are granular cell tumours of histiocytic origin. In addition, the five adult NSE-S100 tumours show strong laminin-immunostaining around the single small or syncytial granular cells, whereas pericellular laminin is not detectable in the histiocytic nor in the three congenital tumours. None of the tumours shows any staining for lysozyme, epithelial, muscular, leukocyte, neurofilament or glial antigens. PMID:3004014

  13. Morphology of Tumours Induced in Hamsters by CELO Virus, Tumour Tissue, and Tumour Cells Grown in Culture*

    PubMed Central

    Mancini, L. O.; Jasty, V.; Anderson, J.; Yates, V. J.

    1972-01-01

    Tumours in hamsters, induced by the chicken-embryo-lethal-orphan (CELO) virus, by tumour tissue transplants, or by tumour cells grown in culture, were well circumscribed solid tumours and covered by a thin capsule-like structure. All were fibrosarcomata. However, tumours produced by the 3 inocula exhibited the following histological differences. Neoplasms induced by CELO virus were generally less differentiated and were composed of cells with polygonal or oval nuclei and indistinct cytoplasmic boundaries. Numerous multinucleated bizarre giant cells were found. Those produced by tumour tissue transplants were more differentiated and were composed of spindle shaped cells with abundant collagen fibre formation. Neoplasms induced by tumour cells grown in culture were generally undifferentiated with many mitotic figures and contained numerous giant cells. Cells from tumours induced by CELO virus or tumour transplants produced similar morphologies when cultured in vitro. The cell cultures consisted of large cells with oval or rounded large nuclei and prominent nucleoli. Multinucleated giant cells, cells in mitosis, and a disorganized growth pattern were also characteristic of the cell cultures. However, mitosis and a piling-up of cells occurred more frequently with cell cultures derived from the CELO virus-induced tumour. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6 PMID:4335495

  14. Gastroenteropancreatic neuroendocrine tumours: an overview.

    PubMed

    Davies, Louise; Weickert, Martin O

    2016-02-25

    Gastroenteropancreatic neuroendocrine tumours (GEP-NET) represent a heterogeneous family of diseases of often challenging clinical management. Although many GEP-NET are slow progressing and frequently less aggressive than neoplasms of other origin, they can metastasise and reduce the life span of the patient. GEP-NET can be functioning (secreting hormones that may cause symptoms and organ damage), but some 60% are non-functioning. Thorough clinical assessment including family history, biochemical tests, radiology and nuclear medicine scans, and histological confirmation are important to tailor the optimal treatment of GEP-NET, which should be managed with a multidisciplinary approach and mainly guided by tumour grading and staging, functioning status, and location of the primary lesion. PMID:26911175

  15. Giant Cell Tumour of Soft Tissue in Neck: An Uncommon Tumour in an Uncommon Location

    PubMed Central

    Bandyopadhyay, Abhishek; Medda, Sripurna; Dey, Soumit; Paul, Prabir Chandra

    2015-01-01

    Giant cell tumour of soft tissue is an extremely rare tumour. It is thought to be the soft tissue counterpart of giant cell tumours of the bone due to its histological and immunohistochemical resemblances. Almost 80% of these tumours occur in upper and lower extremities; neck is a very rare location. Here we describe a case of primary soft tissue giant cell tumour in right submandibular region. A 35-year-old male patient presented with a swelling in right submandibular area. FNAC suggested a benign soft tissue neoplasm, comprising of spindle cells and multinucleated giant cells. Histopathology of resected specimen showed spindle cell tumour with intricately mixed giant cells, consistent with a primary giant cell tumour of soft tissue. Giant cells were CD 68 positive. Giant cell tumour of soft tissue is benign tumour, though very rarely can show features of malignancy. We present this case for its rarity and morphological overlap with other soft tissue neoplasms containing giant cells. PMID:26816906

  16. Mobile phones and head tumours. The discrepancies in cause-effect relationships in the epidemiological studies - how do they arise?

    PubMed Central

    2011-01-01

    Background Whether or not there is a relationship between use of mobile phones (analogue and digital cellulars, and cordless) and head tumour risk (brain tumours, acoustic neuromas, and salivary gland tumours) is still a matter of debate; progress requires a critical analysis of the methodological elements necessary for an impartial evaluation of contradictory studies. Methods A close examination of the protocols and results from all case-control and cohort studies, pooled- and meta-analyses on head tumour risk for mobile phone users was carried out, and for each study the elements necessary for evaluating its reliability were identified. In addition, new meta-analyses of the literature data were undertaken. These were limited to subjects with mobile phone latency time compatible with the progression of the examined tumours, and with analysis of the laterality of head tumour localisation corresponding to the habitual laterality of mobile phone use. Results Blind protocols, free from errors, bias, and financial conditioning factors, give positive results that reveal a cause-effect relationship between long-term mobile phone use or latency and statistically significant increase of ipsilateral head tumour risk, with biological plausibility. Non-blind protocols, which instead are affected by errors, bias, and financial conditioning factors, give negative results with systematic underestimate of such risk. However, also in these studies a statistically significant increase in risk of ipsilateral head tumours is quite common after more than 10 years of mobile phone use or latency. The meta-analyses, our included, examining only data on ipsilateral tumours in subjects using mobile phones since or for at least 10 years, show large and statistically significant increases in risk of ipsilateral brain gliomas and acoustic neuromas. Conclusions Our analysis of the literature studies and of the results from meta-analyses of the significant data alone shows an almost doubling of the risk of head tumours induced by long-term mobile phone use or latency. PMID:21679472

  17. Gene expression biomarkers in the brain of a mouse model for Alzheimer's disease: mining of microarray data by logic classification and feature selection.

    PubMed

    Arisi, Ivan; D'Onofrio, Mara; Brandi, Rossella; Felsani, Armando; Capsoni, Simona; Drovandi, Guido; Felici, Giovanni; Weitschek, Emanuel; Bertolazzi, Paola; Cattaneo, Antonino

    2011-01-01

    The identification of early and stage-specific biomarkers for Alzheimer's disease (AD) is critical, as the development of disease-modification therapies may depend on the discovery and validation of such markers. The identification of early reliable biomarkers depends on the development of new diagnostic algorithms to computationally exploit the information in large biological datasets. To identify potential biomarkers from mRNA expression profile data, we used the Logic Mining method for the unbiased analysis of a large microarray expression dataset from the anti-NGF AD11 transgenic mouse model. The gene expression profile of AD11 brain regions was investigated at different neurodegeneration stages by whole genome microarrays. A new implementation of the Logic Mining method was applied both to early (1-3 months) and late stage (6-15 months) expression data, coupled to standard statistical methods. A small number of "fingerprinting" formulas was isolated, encompassing mRNAs whose expression levels were able to discriminate between diseased and control mice. We selected three differential "signature" genes specific for the early stage (Nudt19, Arl16, Aph1b), five common to both groups (Slc15a2, Agpat5, Sox2ot, 2210015, D19Rik, Wdfy1), and seven specific for late stage (D14Ertd449, Tia1, Txnl4, 1810014B01Rik, Snhg3, Actl6a, Rnf25). We suggest these genes as potential biomarkers for the early and late stage of AD-like neurodegeneration in this model and conclude that Logic Mining is a powerful and reliable approach for large scale expression data analysis. Its application to large expression datasets from brain or peripheral human samples may facilitate the discovery of early and stage-specific AD biomarkers. PMID:21321390

  18. Multivariate meta-analysis of proteomics data from human prostate and colon tumours

    PubMed Central

    2010-01-01

    Background There is a vast need to find clinically applicable protein biomarkers as support in cancer diagnosis and tumour classification. In proteomics research, a number of methods can be used to obtain systemic information on protein and pathway level on cells and tissues. One fundamental tool in analysing protein expression has been two-dimensional gel electrophoresis (2DE). Several cancer 2DE studies have reported partially redundant lists of differently expressed proteins. To be able to further extract valuable information from existing 2DE data, the power of a multivariate meta-analysis will be evaluated in this work. Results We here demonstrate a multivariate meta-analysis of 2DE proteomics data from human prostate and colon tumours. We developed a bioinformatic workflow for identifying common patterns over two tumour types. This included dealing with pre-processing of data and handling of missing values followed by the development of a multivariate Partial Least Squares (PLS) model for prediction and variable selection. The variable selection was based on the variables performance in the PLS model in combination with stability in the validation. The PLS model development and variable selection was rigorously evaluated using a double cross-validation scheme. The most stable variables from a bootstrap validation gave a mean prediction success of 93% when predicting left out test sets on models discriminating between normal and tumour tissue, common for the two tumour types. The analysis conducted in this study identified 14 proteins with a common trend between the tumour types prostate and colon, i.e. the same expression profile between normal and tumour samples. Conclusions The workflow for meta-analysis developed in this study enabled the finding of a common protein profile for two malign tumour types, which was not possible to identify when analysing the data sets separately. PMID:20849579

  19. PET imaging of primary mediastinal tumours.

    PubMed Central

    Kubota, K.; Yamada, S.; Kondo, T.; Yamada, K.; Fukuda, H.; Fujiwara, T.; Ito, M.; Ido, T.

    1996-01-01

    Mediastinal masses include a wide variety of tumours and remain an interesting diagnostic challenge for radiologist. We performed positron emission tomography (PET) studies of primary mediastinal tumours in order to predict the malignancy of these tumours preoperatively. Twenty-two patients with primary mediastinal tumours were studied with PET using 2-deoxy-2-[18F]fluoro-D-glucose (FDG). The histological findings of surgical pathology or biopsy, or mediastinoscopy were compared with those of computerised tomography (CT) and PET. PET images were evaluated semiquantitatively using the differential uptake ratio (DUR). Increased FDG uptake was observed in nine of ten patients with malignant tumours, including thymic carcinomas, lymphomas, invasive thymomas and a case of sarcoidosis. A moderate level of FDG uptake was found in a myeloma, non-invasive thymomas, and a schwannoma, whereas a low uptake was observed in a teratoma and various benign cysts. The mean FDG uptake of malignant tumours was significantly higher than that of benign tumours. Both thymic cancer and invasive thymoma showed a high FDG uptake. CT examination resulted in three false-negative and two false-positive cases when used in predicting tumour invasion, while PET was associated with a false-positive and a false-negative case. In conclusion, the use of FDG with PET is clinically helpful in evaluating the malignant nature of primary mediastinal tumours. Our results also suggest that a high FDG uptake reflects the invasiveness of malignant nature of thymic tumours. Images Figure 1 Figure 2 PMID:8611400

  20. Microenvironment-induced PTEN loss by exosomal microRNA primes brain metastasis outgrowth.

    PubMed

    Zhang, Lin; Zhang, Siyuan; Yao, Jun; Lowery, Frank J; Zhang, Qingling; Huang, Wen-Chien; Li, Ping; Li, Min; Wang, Xiao; Zhang, Chenyu; Wang, Hai; Ellis, Kenneth; Cheerathodi, Mujeeburahiman; McCarty, Joseph H; Palmieri, Diane; Saunus, Jodi; Lakhani, Sunil; Huang, Suyun; Sahin, Aysegul A; Aldape, Kenneth D; Steeg, Patricia S; Yu, Dihua

    2015-11-01

    The development of life-threatening cancer metastases at distant organs requires disseminated tumour cells' adaptation to, and co-evolution with, the drastically different microenvironments of metastatic sites. Cancer cells of common origin manifest distinct gene expression patterns after metastasizing to different organs. Clearly, the dynamic interaction between metastatic tumour cells and extrinsic signals at individual metastatic organ sites critically effects the subsequent metastatic outgrowth. Yet, it is unclear when and how disseminated tumour cells acquire the essential traits from the microenvironment of metastatic organs that prime their subsequent outgrowth. Here we show that both human and mouse tumour cells with normal expression of PTEN, an important tumour suppressor, lose PTEN expression after dissemination to the brain, but not to other organs. The PTEN level in PTEN-loss brain metastatic tumour cells is restored after leaving the brain microenvironment. This brain microenvironment-dependent, reversible PTEN messenger RNA and protein downregulation is epigenetically regulated by microRNAs from brain astrocytes. Mechanistically, astrocyte-derived exosomes mediate an intercellular transfer of PTEN-targeting microRNAs to metastatic tumour cells, while astrocyte-specific depletion of PTEN-targeting microRNAs or blockade of astrocyte exosome secretion rescues the PTEN loss and suppresses brain metastasis in vivo. Furthermore, this adaptive PTEN loss in brain metastatic tumour cells leads to an increased secretion of the chemokine CCL2, which recruits IBA1-expressing myeloid cells that reciprocally enhance the outgrowth of brain metastatic tumour cells via enhanced proliferation and reduced apoptosis. Our findings demonstrate a remarkable plasticity of PTEN expression in metastatic tumour cells in response to different organ microenvironments, underpinning an essential role of co-evolution between the metastatic cells and their microenvironment during the adaptive metastatic outgrowth. Our findings signify the dynamic and reciprocal cross-talk between tumour cells and the metastatic niche; importantly, they provide new opportunities for effective anti-metastasis therapies, especially of consequence for brain metastasis patients. PMID:26479035

  1. Tumour location within the breast: Does tumour site have prognostic ability?

    PubMed Central

    Rummel, Seth; Hueman, Matthew T; Costantino, Nick; Shriver, Craig D; Ellsworth, Rachel E

    2015-01-01

    Introduction Tumour location within the breast varies with the highest frequency in the upper outer quadrant (UOQ) and lowest frequency in the lower inner quadrant (LIQ). Whether tumour location is prognostic is unclear. To determine whether tumour location is prognostic, associations between tumour site and clinicopathological characteristics were evaluated. Materials and Methods All patients enrolled in the Clinical Breast Care Project whose tumour site—UOQ, upper inner quadrant (UIQ), central, LIQ, lower outer quadrant (LOQ)—was determined by a single, dedicated breast pathologist were included in this study. Patients with multicentric disease (n = 122) or tumours spanning multiple quadrants (n = 381) were excluded from further analysis. Clinicopathological characteristics were analysed using chi-square tests for univariate analysis with multivariate analysis performed using principal components analysis (PCA) and multiple logistic regression. Significance was defined as P < 0.05. Results Of the 980 patients with defined tumour location, 30 had bilateral disease. Tumour location in the UOQ (51.5%) was significantly higher than in the UIQ (15.6%), LOQ (14.2%), central (10.6%), or LIQ (8.1%). Tumours in the central quadrant were significantly more likely to have higher tumour stage (P = 0.003) and size (P < 0.001), metastatic lymph nodes (P < 0.001), and mortality (P = 0.011). After multivariate analysis, only tumour size and lymph node status remained significantly associated with survival. Conclusions Evaluation of tumour location as a prognostic factor revealed that although tumours in the central region are associated with less favourable outcome, these associations are not independent of location but rather driven by larger tumour size. Tumours in the central region are more difficult to detect mammographically, resulting in larger tumour size at diagnosis and thus less favourable prognosis. Together, these data demonstrate that tumour location is not an independent prognostic factor. PMID:26284116

  2. Low-level and high-level modulations of fixational saccades and high frequency oscillatory brain activity in a visual object classification task

    PubMed Central

    Kosilo, Maciej; Wuerger, Sophie M.; Craddock, Matt; Jennings, Ben J.; Hunt, Amelia R.; Martinovic, Jasna

    2013-01-01

    Until recently induced gamma-band activity (GBA) was considered a neural marker of cortical object representation. However, induced GBA in the electroencephalogram (EEG) is susceptible to artifacts caused by miniature fixational saccades. Recent studies have demonstrated that fixational saccades also reflect high-level representational processes. Do high-level as opposed to low-level factors influence fixational saccades? What is the effect of these factors on artifact-free GBA? To investigate this, we conducted separate eye tracking and EEG experiments using identical designs. Participants classified line drawings as objects or non-objects. To introduce low-level differences, contours were defined along different directions in cardinal color space: S-cone-isolating, intermediate isoluminant, or a full-color stimulus, the latter containing an additional achromatic component. Prior to the classification task, object discrimination thresholds were measured and stimuli were scaled to matching suprathreshold levels for each participant. In both experiments, behavioral performance was best for full-color stimuli and worst for S-cone isolating stimuli. Saccade rates 200–700 ms after stimulus onset were modulated independently by low and high-level factors, being higher for full-color stimuli than for S-cone isolating stimuli and higher for objects. Low-amplitude evoked GBA and total GBA were observed in very few conditions, showing that paradigms with isoluminant stimuli may not be ideal for eliciting such responses. We conclude that cortical loops involved in the processing of objects are preferentially excited by stimuli that contain achromatic information. Their activation can lead to relatively early exploratory eye movements even for foveally-presented stimuli. PMID:24391611

  3. Low-level and high-level modulations of fixational saccades and high frequency oscillatory brain activity in a visual object classification task.

    PubMed

    Kosilo, Maciej; Wuerger, Sophie M; Craddock, Matt; Jennings, Ben J; Hunt, Amelia R; Martinovic, Jasna

    2013-01-01

    Until recently induced gamma-band activity (GBA) was considered a neural marker of cortical object representation. However, induced GBA in the electroencephalogram (EEG) is susceptible to artifacts caused by miniature fixational saccades. Recent studies have demonstrated that fixational saccades also reflect high-level representational processes. Do high-level as opposed to low-level factors influence fixational saccades? What is the effect of these factors on artifact-free GBA? To investigate this, we conducted separate eye tracking and EEG experiments using identical designs. Participants classified line drawings as objects or non-objects. To introduce low-level differences, contours were defined along different directions in cardinal color space: S-cone-isolating, intermediate isoluminant, or a full-color stimulus, the latter containing an additional achromatic component. Prior to the classification task, object discrimination thresholds were measured and stimuli were scaled to matching suprathreshold levels for each participant. In both experiments, behavioral performance was best for full-color stimuli and worst for S-cone isolating stimuli. Saccade rates 200-700 ms after stimulus onset were modulated independently by low and high-level factors, being higher for full-color stimuli than for S-cone isolating stimuli and higher for objects. Low-amplitude evoked GBA and total GBA were observed in very few conditions, showing that paradigms with isoluminant stimuli may not be ideal for eliciting such responses. We conclude that cortical loops involved in the processing of objects are preferentially excited by stimuli that contain achromatic information. Their activation can lead to relatively early exploratory eye movements even for foveally-presented stimuli. PMID:24391611

  4. Subject Classification.

    ERIC Educational Resources Information Center

    Thompson, Gayle; And Others

    Three newspaper librarians described how they manage the files of newspaper clippings which are a necessary part of their collections. The development of a new subject classification system for the clippings files was outlined. The new subject headings were based on standard subject heading lists and on local need. It was decided to use a computer…

  5. Classifying Classification

    ERIC Educational Resources Information Center

    Novakowski, Janice

    2009-01-01

    This article describes the experience of a group of first-grade teachers as they tackled the science process of classification, a targeted learning objective for the first grade. While the two-year process was not easy and required teachers to teach in a new, more investigation-oriented way, the benefits were great. The project helped teachers and…

  6. Benign tumours of the bone: A review?

    PubMed Central

    Hakim, David N.; Pelly, Theo; Kulendran, Myutan; Caris, Jochem A.

    2015-01-01

    Benign tumours of the bone are not cancerous and would not metastasise to other regions of the body. However, they can occur in any part of the skeleton, and can still be dangerous as they may grow and compress healthy bone tissue. There are several types of benign tumours that can be classified by the type of matrix that the tumour cells produce; such as bone, cartilage, fibrous tissue, fat or blood vessel. Overall, 8 different types can be distinguished: osteochondroma, osteoma, osteoid osteoma, osteoblastoma, giant cell tumour, aneurysmal bone cyst, fibrous dysplasia and enchondroma. The incidence of benign bone tumours varies depending on the type. However, they most commonly arise in people less than 30 years old, often triggered by the hormones that stimulate normal growth. The most common type is osteochondroma. This review discusses the different types of common benign tumours of the bone based on information accumulated from published literature. PMID:26579486

  7. Classification of endometrial carcinoma: more than two types.

    PubMed

    Murali, Rajmohan; Soslow, Robert A; Weigelt, Britta

    2014-06-01

    Endometrial cancer is the most common gynaecological malignancy in Europe and North America. Traditional classification of endometrial carcinoma is based either on clinical and endocrine features (eg, types I and II) or on histopathological characteristics (eg, endometrioid, serous, or clear-cell adenocarcinoma). Subtypes defined by the different classification systems correlate to some extent, but there is substantial heterogeneity in biological, pathological, and molecular features within tumour types from both classification systems. In this Review we provide an overview of traditional and newer genomic classifications of endometrial cancer. We discuss how a classification system that incorporates genomic and histopathological features to define biologically and clinically relevant subsets of the disease would be useful. Such integrated classification might facilitate development of treatments tailored to specific disease subgroups and could potentially enable delivery of precision medicine to patients with endometrial cancer. PMID:24872110

  8. Neural-network-based classification of cognitively normal, demented, Alzheimer disease and vascular dementia from single photon emission with computed tomography image data from brain.

    PubMed Central

    deFigueiredo, R J; Shankle, W R; Maccato, A; Dick, M B; Mundkur, P; Mena, I; Cotman, C W

    1995-01-01

    Single photon emission with computed tomography (SPECT) hexamethylphenylethyleneamineoxime technetium-99 images were analyzed by an optimal interpolative neural network (OINN) algorithm to determine whether the network could discriminate among clinically diagnosed groups of elderly normal, Alzheimer disease (AD), and vascular dementia (VD) subjects. After initial image preprocessing and registration, image features were obtained that were representative of the mean regional tissue uptake. These features were extracted from a given image by averaging the intensities over various regions defined by suitable masks. After training, the network classified independent trials of patients whose clinical diagnoses conformed to published criteria for probable AD or probable/possible VD. For the SPECT data used in the current tests, the OINN agreement was 80 and 86% for probable AD and probable/possible VD, respectively. These results suggest that artificial neural network methods offer potential in diagnoses from brain images and possibly in other areas of scientific research where complex patterns of data may have scientifically meaningful groupings that are not easily identifiable by the researcher. Images Fig. 1 PMID:7777543

  9. Ghrelin expression in neuroendocrine tumours of the gastrointestinal tract with multiple endocrine neoplasia type 1.

    PubMed

    Raffel, A; Krausch, M; Cupisti, K; Gerharz, C D; Eisenberger, C F; Knoefel, W T

    2005-10-01

    Ghrelin is a novel gastrointestinal-brain hormone that was first described by Kojima et al. as a growth-hormone-releasing peptide. It can be isolated and purified from different tissues. Evidence of antiproliferative effects in neoplastic cells (binding to normal and neoplastic tissues) supports the hypothesis that ghrelin also plays an important role in endocrine regulation. Whether ghrelin may be involved in formation of neuroendocrine tumours (NET) of the gastrointestinal tract (GIT) in cases of MEN-1 is under discussion. Over the last sixteen years, 227 patients with GIT NET were treated at our institution. Mutations of the menin gene were identified in twelve patients. Eleven of these tumours (islet cell tumours) were localized in the pancreas and one in the stomach. Tissues from these tumours were resected, fixed in formalin and embedded in paraffin. Sections were examined by immunohistochemistry with a primary antibody for ghrelin. Three out of twelve NET in MEN-1 patients (25%) showed ghrelin expression by immunohistochemistry. Comparison between ghrelin-positive and ghrelin-negative tumours regarding biological activity, morphological aspects and clinicopathological parameters shows no substantial differences. The reported incidence of ghrelin expression in NET of the gastrointestinal tract by MEN-1 was not seen in our patients. Whether or not ghrelin has an influence on neuroendocrine tumour development related to deficient menin-genes is unknown. PMID:16278790

  10. Spinal cord tumours: advances in genetics and their implications for treatment

    PubMed Central

    Zadnik, Patricia L.; Gokaslan, Ziya L.; Burger, Peter C.; Bettegowda, Chetan

    2014-01-01

    Tumours of the spinal cord, although rare, are associated with high morbidity. Surgical resection remains the primary treatment for patients with this disease, and offers the best chance for cure. Such surgical procedures, however, carry substantial risks such as worsening of neurological deficit, paralysis and death. New therapeutic avenues for spinal cord tumours are needed, but genetic studies of the molecular mechanisms governing tumourigenesis in the spinal cord are limited by the scarcity of high-quality human tumour samples. Many spinal cord tumours have intracranial counterparts that have been extensively studied, but emerging data show that the tumours are genetically and biologically distinct. The differences between brain and spine tumours make extrapolation of data from one to the other difficult. In this Review, we describe the demographics, genetics and current treatment approaches for the most commonly encountered spinal cord tumours—namely, ependymomas, astrocytomas, haemangioblastomas and meningiomas. We highlight advances in understanding of the biological basis of these lesions, and explain how the latest progress in genetics and beyond are being translated to improve patient care. PMID:23528542

  11. Primary intracranial germ cell tumours: experience of a single South-East Asian institution.

    PubMed

    Foo, Aaron S C; Lim, Cindy; Chong, Dawn Q Q; Tan, Daniel Y H; Tham, Chee Kian

    2014-10-01

    Primary intracranial germ cell tumours (ICGCT) are a rare group of brain tumours arising predominantly in the paediatric and pre-adult population, accounting for up to 9.5% of paediatric brain tumours in East Asia. The National Cancer Centre Singapore (NCCS) is a tertiary referral centre for patients from all over South-East Asia. Our study aims to describe the characteristics of ICGCT patients in South-East Asia. Data on all patients with ICGCT who were seen at the Therapeutic Radiology Department of NCCS from 2000 to 2013 were collected retrospectively. Patient demographics, disease characteristics and treatment outcomes were analysed. Characteristics and survival of our patients were similar to other centres. Pure germinomas demonstrated 5 year overall survival (OS) and disease-free survival (DFS) rates of 89.2% (95% confidence interval [CI] 60.2-97.5) and 85.2% (95%CI 60.8-95.0) respectively. Secreting germinomas, non-germinomatous germ cell tumours and mixed germ cell tumours were evaluated together and demonstrated 5 year OS of 70.6% (95%CI 41.0-87.3) and DFS of 61.4% (95%CI 31.9-81.3). Patients ? 12 years had marginally better 5 year OS than their older counterparts (81.0% [95%CI 49.5-93.9] versus 77.9% [95%CI 47.3-92.0], respectively). Patients who underwent extended field radiotherapy had longer OS and DFS than those who received local field irradiation. Treatment outcomes of our ICGCT patients are comparable with those in other Asian and Western centres. Extended field radiotherapy is a pivotal component of ICGCT treatment. Adding chemotherapy confers no extra survival benefit in treating germinomas. Treatment of mixed germ cell tumours and non-germinomatous germ cell tumours involves a multidisciplinary approach that varies for each histological subtype. PMID:24954243

  12. Parallel progression of primary tumours and metastases.

    PubMed

    Klein, Christoph A

    2009-04-01

    Systemic cancer progression is accounted for in two basic models. The prevailing archetype places the engine of cancer progression within the primary tumour before metastatic dissemination of fully malignant cells. The second posits parallel, independent progression of metastases arising from early disseminated tumour cells. This Perspective draws together data from disease courses, tumour growth rates, autopsy studies, clinical trials and molecular genetic analyses of primary and disseminated tumour cells in support of the parallel progression model. Consideration of this model urges review of current diagnostic and therapeutic routines. PMID:19308069

  13. The heterogeneity of solid human xenotransplant tumours.

    PubMed

    Wagner, W

    1991-01-01

    Fifteen xenograft tumour lines (4 osteosarcomas and 11 squamous carcinomas) were established on nude mice in numerous passages. Over a period of 4 years, samples were taken and studied systematically in more than 4000 histological slides. Of the tumour lines, 12 (4 osteosarcomas and 8 squamous carcinomas) showed remarkable dedifferentiation, but also redifferentiation towards a higher grade. There was a correlation between the rate of tumour takes in mice and poor prognosis in patients, but none between tumour doubling time and the phases of the cell cycle. Altogether, the results showed a great heterogeneity of human xenotransplants in terms of biological behaviour and morphological changes. PMID:1744163

  14. Tumour promotion versus tumour suppression in chronic hepatic iron overload.

    PubMed

    Bloomer, Steven A; Brown, Kyle E

    2015-06-01

    Although iron-catalysed oxidative damage is presumed to be a major mechanism of injury leading to cirrhosis and hepatocellular carcinoma in hemochromatosis, these events have been difficult to recapitulate in an animal model. In this study, we evaluated regulators of hepatocarcinogenesis in a rodent model of chronic iron overload. Sprague-Dawley rats were iron loaded with iron dextran over 6?months. Livers were harvested and analysed for markers of oxidative stress, as well as the following proteins: p53, murine double minute 2, the Shc proteins p66, p52, p46; ?-catenin, CHOP, C/EBP? and Yes-associated protein. In this model, iron loading is associated with hepatocyte proliferation, and indices of oxidative damage are mildly increased in tandem with augmented antioxidant defenses. Alterations potentially favouring carcinogenesis included a modest but significant decrease in p53 levels and increases in p52, p46 and ?-catenin levels compared with control livers. Countering these factors, the iron-loaded livers demonstrated a significant decrease in CHOP, which has recently been implicated in the development of hepatocellular carcinoma, as well as a reciprocal increase in C/EBP? and decrease in Yes-associated protein. Our results suggest that chronic iron overload elicits both tumour suppressive as well as tumour-promoting mechanisms in rodent liver. PMID:26059599

  15. Tumour-to-tumour metastases: prostate carcinoma metastasising to a renal oncocytoma

    PubMed Central

    Petts, Gemma; Rashid, Tina; Hrouda, David; Ngo, Nye-Thane

    2013-01-01

    This is a case report of prostate carcinoma metastasising to a renal oncocytoma. The report demonstrates the unusual presentation of metastases from a common cancer to a common benign tumour, and reviews the rare phenomenon of tumour-to-tumour metastases. PMID:23307454

  16. Large cell neuroendocrine – Adenocarcinona mixed tumour of colon: Collision tumour with peculiar behaviour. What do we know about these tumours?

    PubMed Central

    Minaya-Bravo, Ana María; Garcia Mahillo, Julio Cesar; Mendoza Moreno, Fernando; Noguelares Fraguas, Fernando; Granell, Javier

    2015-01-01

    Introduction Mixed glandular-endocrine carcinomas are rare tumours of gastrointestinal tract (MANEC). They are more frequent in stomach and hardly one hundred cases have been described in colon. According to Lewis, they are classified into collision (side by side pattern), composite (intermingled) or amphicrine (neuroendocrine and glandular features inside a same cell). Collision tumours are related to biclonal theory: two simultaneous cancerogenic events. Conversely, multidirectional differentiation from a stem cell is accepted as origin of composite tumours. The aim of this paper is to analyse the behaviour of these tumours, with an especial concern about how these tumours metastasise, and the different theories about carcinogenesis. Presentation of case We report a rare case of collision adenocarcinoma-large cell neuroendocrine tumour of colon that after a three-year period of follow-up has presented a retroperitoneal recurrence that features adenocarcinoma and large cell neuroendocrine components. Discussion After an exhaustive review of the English literature, we found that only two cases of collision tumour of colon with metastases showing glandular and endocrine components have been described up to date, so we report the third case, and the first happening in transverse colon. Conclusion We conclude that not all collision tumours follow the biclonal theory and more studies are needed to clarify the origin of these neoplasms, and consequently, to reach an adequate treatment. PMID:26635955

  17. Electrochemotherapy on liver tumours in rabbits.

    PubMed Central

    Ramirez, L. H.; Orlowski, S.; An, D.; Bindoula, G.; Dzodic, R.; Ardouin, P.; Bognel, C.; Belehradek, J.; Munck, J. N.; Mir, L. M.

    1998-01-01

    Electrochemotherapy (ECT) is a new therapeutic approach combining the effects of a low-permeant cytotoxic drug, bleomycin (BLM), administered i.v. and cell-permeabilizing electric pulses (EPs) locally delivered to tumours. The transient permeabilization of the cell membrane by the EPs allows free access of BLM to its intracellular targets, largely enhancing BLM's cytotoxic effects. ECT efficacy has been proved so far on transplanted subcutaneous murine tumours and on subcutaneous metastases in humans. Here, we present the first study of the effects of ECT on tumours transplanted to livers in rabbits. We used a recently developed EP applicator consisting of an array of parallel and equidistant needles to be inserted in tissues. Effects of EPs alone or of ECT were assessed by histological analysis, tumour growth rates and survival of the treated animals. A transient blood hypoperfusion was seen in the electropulsed areas, with or without BLM, related to EP-dependent vasoconstriction but this had no major effects on cell survival. Long-term effects depended on the presence of BLM at the time of EP delivery. Almost complete tumour necrosis was observed after ECT, resulting from both BLM direct cytotoxic effects on electropermeabilized tumour cells and indirect effects on the tumour vessels. A large reduction in tumour growth rate and significantly longer survival times were scored in comparison with control rabbits. Moreover, ECT of liver tumours was well tolerated and devoid of systemic side-effects. When ECT was associated with a local interleukin 2-based immunotherapy, increased local anti-tumour effectiveness as well as a large decrease in the number of metastases were observed. Thus, ECT could become a novel treatment modality for liver tumours and other solid internal malignancies. Images Figure 1 Figure 2 PMID:9649121

  18. Training for planning tumour resection: augmented reality and human factors.

    PubMed

    Abhari, Kamyar; Baxter, John S H; Chen, Elvis C S; Khan, Ali R; Peters, Terry M; de Ribaupierre, Sandrine; Eagleson, Roy

    2015-06-01

    Planning surgical interventions is a complex task, demanding a high degree of perceptual, cognitive, and sensorimotor skills to reduce intra- and post-operative complications. This process requires spatial reasoning to coordinate between the preoperatively acquired medical images and patient reference frames. In the case of neurosurgical interventions, traditional approaches to planning tend to focus on providing a means for visualizing medical images, but rarely support transformation between different spatial reference frames. Thus, surgeons often rely on their previous experience and intuition as their sole guide is to perform mental transformation. In case of junior residents, this may lead to longer operation times or increased chance of error under additional cognitive demands. In this paper, we introduce a mixed augmented-/virtual-reality system to facilitate training for planning a common neurosurgical procedure, brain tumour resection. The proposed system is designed and evaluated with human factors explicitly in mind, alleviating the difficulty of mental transformation. Our results indicate that, compared to conventional planning environments, the proposed system greatly improves the nonclinicians' performance, independent of the sensorimotor tasks performed ( ). Furthermore, the use of the proposed system by clinicians resulted in a significant reduction in time to perform clinically relevant tasks ( ). These results demonstrate the role of mixed-reality systems in assisting residents to develop necessary spatial reasoning skills needed for planning brain tumour resection, improving patient outcomes. PMID:25546854

  19. Immunohistochemical expression of amelogenins in odontogenic epithelial tumours and cysts.

    PubMed

    Mori, M; Yamada, K; Kasai, T; Yamada, T; Shimokawa, H; Sasaki, S

    1991-01-01

    Amelogenins, enamel proteins in odontogenic tumours, were detected immunohistochemically using a monoclonal antibody. They were strongly expressed in amyloid-like material, ghost cells, and the cells surrounding ghost cells of calcifying epithelial odontogenic tumours and cysts, whereas calcified bodies within the tumours and cysts showed negative staining. The expression of amelogenins was also positive in tumour cells of ameloblastoma, adenomatoid odontogenic tumour, squamous odontogenic tumour and ameloblastic fibroma. Peripheral tumour cells of the follicular ameloblastoma were positive with relatively intense staining. Undifferentiated or flattened tumour cells of adenomatoid odontogenic tumour and non-keratinized tumour cells of the squamous odontogenic tumour showed marked staining. Reduced ameloblasts in the odontoma displayed the strongest staining for amelogenins. The study suggests that biosynthesis of amelogenins may occur in the homogeneous materials of calcifying epithelial odontogenic tumours and cysts. PMID:2024453

  20. Cellular interactions modulating host resistance to tumours.

    PubMed

    Baldwin, R W; Byers, V S; Hannant, D; Jones, J A; Pimm, M V; Price, M R

    1982-01-01

    Active specific immunotherapy of carcinogen-induced rat tumours can be effected using vaccines containing tumour cells admixed with bacterial vaccines such as BCG and C. parvum. The nature of the tumour antigen preparation is important, the most effective immunogen being viable tumour cells whose growth is controlled by responses generated by the bacterial agent in the vaccine. Soluble tumour antigen preparations are usually ineffective due to the preferential induction of suppressor lymphocyte responses in normal hosts. In comparison, removal of suppressor precursors by cyclophosphamide treatment of animals leads to the development of tumour immunity following immunization with soluble antigen preparations. One component of the immune rejection response involves the generation of non-specific effector cells. This type of response can also be induced by administering chemical hypersensitizing agents so as to localize tumour deposits. This approach has proved highly effective in treating the guinea pig line 10 hepatoma by intralesional injection of alkylcatechols. These compounds are highly potent hypersensitizers, being the active constituents of the poison ivy/oak (urushiol oil), and localize in tumour cell membranes. PMID:7036295

  1. CT/MRI of neuroendocrine tumours

    PubMed Central

    Reznek, Rodney H

    2006-01-01

    Neuroendocrine tumours (NETs) are often thought to be rare and rather recherché cancers which are of little concern to the general physician, surgeon or radiologist because of their rarity and esoteric nature. In fact, while relatively uncommon, the total group of gastro-entero-pancreatic (GEP) tumours incorporates the spectrum of all types of carcinoids, incuding bronchial carcinoids, and the whole gamut of islet-cell tumours. Some of these may present as functioning tumours, with a plethora of hormonal secretions and concomitant clinical syndromes, and GEPs in general have an incidence around 30 per million population per year. This means that in the whole European Union, for example, there will be in the region of 12000 new patients every year presenting with one or another manifestation of these tumours. Furthermore, the comparatively long survival of many of these patients, compared to more common adenocarcinomas or epithelial tumours, implies that the point prevalence is also not inconsiderable. However, it is undoubtedly true that these tumours can be difficult to identify, especially in their early stages, and it is then that radiological investigation becomes of paramount importance. Having taken into account all these considerations, most investigators would initiate investigation of a suspected or biochemically proven islet-cell tumour with cross-sectional imaging—either CT or MRI. This will clearly identify the larger lesions, allow assessment of the entire abdomen, and provide valuable information on the presence of hepatic metastates. PMID:17114072

  2. FDG uptake, a surrogate of tumour hypoxia?

    PubMed Central

    Van de Wiele, Christophe

    2008-01-01

    Introduction Tumour hyperglycolysis is driven by activation of hypoxia-inducible factor-1 (HIF-1) through tumour hypoxia. Accordingly, the degree of 2-fluro-2-deoxy-d-glucose (FDG) uptake by tumours might indirectly reflect the level of hypoxia, obviating the need for more specific radiopharmaceuticals for hypoxia imaging. Discussion In this paper, available data on the relationship between hypoxia and FDG uptake by tumour tissue in vitro and in vivo are reviewed. In pre-clinical in vitro studies, acute hypoxia was consistently shown to increase FDG uptake by normal and tumour cells within a couple of hours after onset with mobilisation or modification of glucose transporters optimising glucose uptake, followed by a delayed response with increased rates of transcription of GLUT mRNA. In pre-clinical imaging studies on chronic hypoxia that compared FDG uptake by tumours grown in rat or mice to uptake by FMISO, the pattern of normoxic and hypoxic regions within the human tumour xenografts, as imaged by FMISO, largely correlated with glucose metabolism although minor locoregional differences could not be excluded. In the clinical setting, data are limited and discordant. Conclusion Further evaluation of FDG uptake by various tumour types in relation to intrinsic and bioreductive markers of hypoxia and response to radiotherapy or hypoxia-dependent drugs is needed to fully assess its application as a marker of hypoxia in the clinical setting. PMID:18509637

  3. Characterization of twenty-five ovarian tumour cell lines that phenocopy primary tumours

    PubMed Central

    Ince, Tan A.; Sousa, Aurea D.; Jones, Michelle A.; Harrell, J. Chuck; Agoston, Elin S.; Krohn, Marit; Selfors, Laura M.; Liu, Wenbin; Chen, Ken; Yong, Mao; Buchwald, Peter; Wang, Bin; Hale, Katherine S.; Cohick, Evan; Sergent, Petra; Witt, Abigail; Kozhekbaeva, Zhanna; Gao, Sizhen; Agoston, Agoston T.; Merritt, Melissa A.; Foster, Rosemary; Rueda, Bo R.; Crum, Christopher P.; Brugge, Joan S.; Mills, Gordon B.

    2015-01-01

    Currently available human tumour cell line panels consist of a small number of lines in each lineage that generally fail to retain the phenotype of the original patient tumour. Here we develop a cell culture medium that enables us to routinely establish cell lines from diverse subtypes of human ovarian cancers with >95% efficiency. Importantly, the 25 new ovarian tumour cell lines described here retain the genomic landscape, histopathology and molecular features of the original tumours. Furthermore, the molecular profile and drug response of these cell lines correlate with distinct groups of primary tumours with different outcomes. Thus, tumour cell lines derived using this methodology represent a significantly improved platform to study human tumour pathophysiology and response to therapy. PMID:26080861

  4. Canine transmissible venereal tumour: a review.

    PubMed

    Ganguly, B; Das, U; Das, A K

    2016-03-01

    Canine transmissible venereal tumour (CTVT) is a contagious venereal tumour of dogs, commonly observed in dogs that are in close contact with one another, or in stray and wild dogs that exhibit unrestrained sexual activity. CTVT represents a unique, naturally transmissible, contagious tumour, where the mutated tumour cell itself is the causative agent and perpetuates as a parasitic allograft in the host. Clinical history, signalment and cytological features are often obvious for establishing a diagnosis though biopsy and histological examination may be needed in atypical cases. Most cases are curable with three intravenous injections of vincristine sulphate at weekly intervals. The role of stray and wild dogs makes the disease difficult to control and necessitates sustained animal birth control in stray dogs along with prompt therapy of the affected dogs. This review captures the manifold developments in different areas embracing this fascinating tumour, including its biology, diagnosis and therapeutic alternatives. PMID:23981098

  5. Large benign retroperitoneal tumour in pregnancy

    PubMed Central

    Berczi, Csaba; Osvath, Peter; Flasko, Tibor

    2015-01-01

    A 31-year-old female was in the 13th week of pregnancy when an abdominal ultrasound examination revealed a large retroperitoneal tumour. Magnetic resonance imaging was carried out and the imaging described a 10-cm mass in diameter extending from the right kidney. Given that the patient was in her first trimester and that there was a suspicion of malignancy, further surgical exploration of the tumour was warranted. During the operation, the tumour was removed, but nephrectomy was not necessary. Histologic analysis of the resected tumour showed a mucinous cystic adenoma, and no signs of malignancy were present. Following the surgery, the pregnancy was otherwise uneventful and further complications did not occur. This case illustrates that surgery is recommended in patients with a retroperitoneal tumour early during a pregnancy, when a malignancy cannot be excluded. PMID:26609332

  6. Lifestyle issues and genitourinary tumours.

    PubMed

    Sommer, Frank; Klotz, Theo; Schmitz-Dräger, Bernd J

    2004-02-01

    A variety of lifestyle factors, including physical activity, artificial sweeteners, alcohol consumption and smoking, have been reported to contribute to the risk of developing urological malignancies. A great number of epidemiological studies suggest that sports and physical activity may have a preventive influence on genitourinary tumours, especially on the incidence of prostate cancer. Smoking appears to be the most relevant lifestyle factor significantly increasing both incidence and mortality from bladder cancer. Furthermore, there is evidence implicating an association between tobacco use and kidney cancer. In contrast, prostate and testicular cancers are unlikely to be linked to tobacco use. As far as alcohol is concerned, most studies indicate that neither amount nor type of alcohol seems to be clearly associated with a risk of developing urological malignancies. However, some more recent cohort studies suggest a moderately increased risk for prostate and bladder cancer for specific types of alcohol. On the other hand, there is evidence that moderate alcohol consumption may even protect women from developing renal cancer. Since the introduction of artificial sweeteners, reports of potential cancer risks have circulated periodically through the mass media. The wide distribution of these agents and the fact that mostly combinations of the different compounds are added to a broad variety of food, drinks, drugs, and hygiene products complicates a systematic analysis of their potential impact on the development of urological malignancies. Nevertheless, so far not a single study has convincingly demonstrated a statistically significant risk of bladder cancer due to the consumption of artificial sweeteners. This survey demonstrates that the individual assessment of lifestyle factors not only may identify groups with an increased risk for urological malignancies but also clearly displays a potential for tumour prevention. PMID:14673616

  7. [Epidemiology of brain metastases].

    PubMed

    Taillibert, S; Le Rhun, É

    2015-02-01

    The most frequent intracranial brain tumours are brain metastases. All types of cancer can develop brain metastases but two thirds of brain metastases occurring in adult patients are secondary to one of these three cancers: lung cancer, breast cancer and melanoma. In accordance with these data, this review is focusing on the epidemiology of these three types of cancer. We report here the incidence, risk factors, median time of brain metastases occurrence after diagnosis of the primary cancer, prognosis and median survival for these three types of cancer. We also discuss the clinical implications of these data. The second part of this review is focusing on the Graded Prognostic Assessment scores in all types of primary cancer with brain metastases, how they can be applied in clinical research for a better stratification of patients, and to some extent in clinical practice to guide decisions for personalized treatments. These scores provide a better understanding of the different profiles of clinical evolution that can be observed amongst patients suffering from brain metastases according to the type of primary cancer. We highlighted the most remarkable and useful clinical implications of these data. PMID:25636729

  8. Reaching a Moveable Visual Target: Dissociations in Brain Tumour Patients

    ERIC Educational Resources Information Center

    Buiatti, Tania; Skrap, Miran; Shallice, Tim

    2013-01-01

    Damage to the posterior parietal cortex (PPC) can lead to Optic Ataxia (OA), in which patients misreach to peripheral targets. Recent research suggested that the PPC might be involved not only in simple reaching tasks toward peripheral targets, but also in changing the hand movement trajectory in real time if the target moves. The present study…

  9. [Hereditary and non-hereditary syndromic gastointestinal stromal tumours].

    PubMed

    Agaimy, A; Hartmann, A

    2010-10-01

    The majority of gastrointestinal stromal tumours (GISTs) present as solitary gastrointestinal masses in adults aged 50-70 years. A small subset of GISTs (?5%) occurs in the setting of familial or idiopathic multitumour syndrome. In decreasing order of frequency, neurofibromatosis Recklinghausen (NF-1), Carney triad (gastric GIST, pulmonary chondroma and extra-adrenal paraganglioma), familial GIST syndromes resulting from germline mutations in c-Kit/PDGFRA and the Carney-Stratakis syndrome (hereditary GIST paraganglioma syndrome caused by germline mutations in the mitochondrial tumour suppressor gene pathway involving the succinate dehydrogenase subunits SDHD, SDHC and SDHB) represent the four most important GIST syndromes characterized to date. Since affected patients and their family members require special treatment and/or counseling and follow-up, early diagnosis and precise classification of this likely still underdiagnosed diseases is of the utmost importance. This review summarizes the pertinent clinicopathological and molecular features of the main GIST syndromes to facilitate their diagnosis and distinction from their non-syndromic mimics. PMID:20848108

  10. Frequent and Discriminative Subnetwork Mining for Mild Cognitive Impairment Classification

    PubMed Central

    Fei, Fei; Jie, Biao

    2014-01-01

    Abstract Recent studies on brain networks have suggested that many brain diseases, such as Alzheimer's disease and mild cognitive impairment (MCI), are related to a large-scale brain network, rather than individual brain regions. However, it is challenging to find such a network from the whole brain network due to the complexity of brain networks. In this article, the authors propose a novel method to mine the discriminative subnetworks for classifying MCI patients from healthy controls (HC). Specifically, the authors first extract a set of frequent subnetworks from each of the two groups (i.e., MCI and HC), respectively. Then, measure the discriminative ability of those frequent subnetworks using the graph kernel-based classification method and select the most discriminative subnetworks for subsequent classification. The results on the functional connectivity networks of 12 MCI and 25 HC show that this method can obtain competitive results compared with state-of-the-art methods on MCI classification. PMID:24766561

  11. Neutron medical treatment of tumours — a survey of facilities

    NASA Astrophysics Data System (ADS)

    Wagner, F. M.; Loeper-Kabasakal, B.; Breitkreutz, H.

    2012-03-01

    Neutron therapy has two branches: Fast Neutron Therapy (FNT) and Boron Neutron Capture Therapy (BNCT). The mean neutron energies used for FNT range from 2 MeV to 25 MeV whereas the maximum energy for BNCT is about 10 keV. Neutron generators for FNT have been cyclotrons, accelerators and reactors, whereas BNCT is so far bound to reactors. Both therapies use the effects of high-LET radiation (secondary recoil protons and alpha particles, respectively) and can attack otherwise radioresistant tumours, however, with the hazard of adverse effects for irradiated healthy tissue. FNT has been administered to about 30,000 patients world-wide. From formerly 40 facilities, only eight are operational or stand-by today. The reasons for this development have been, on the one hand, related to technical and economical conditions; on the other hand, strong side effects and insufficient proof of clinical results in the early years as well as increasing competition with new clinical methods have reduced patient numbers. In fact, strict observations of indications, appropriate therapy-planning including low-LET radiation, and consequent treatment of side effects have lead to remarkable results in the meantime. BNCT initially was developed for the treatment of extremely aggressive forms of brain tumour, taking advantage of the action of the blood-brain-barrier which allows for a boronated compound to be selectively enriched in tumour cells. Meanwhile, also malignant melanoma (MM) and Head-and-Neck (H&T) tumours are treated because of their relative radioresistance. At present, epithermal beams with sufficient flux are available only at two facilities. Existing research reactors were indispensable in the development of BNCT, but are to be replaced by hospital-based epithermal neutron sources. Clinical results indicate significantly increased survival times, but the number of patients ever treated is still below 1,000. 3D-dose calculation systems have been developed at several facilities and guarantee a high safety for both therapies, FNT and BNCT.

  12. [Effect of orally administered zinc on the inducibility of experimental brain tumors in the rat].

    PubMed

    Rath, F W; Enke, H

    1984-01-01

    The effect of orally administered zinc on induction and growth of brain tumours in rats was investigated. The brain tumours were induced experimentally by N-ethyl-N-nitrosourea injected subcutaneously in a single dose (17 mg/kg body weight) into newborn BD IX rats. The rats were killed after 180 days. Their brains were cut in serial sections and investigated histologically. The incidence of brain tumours of a control group of rats (group 1) was compared with that of rats which received drinking-water containing 22.8 mmol/l (5.0 g/l) zinc acetate from the 4th week (group 2) or from the 150th day (group 3) after birth. The rats of group 2 developed three times more brain tumours than the rats of the control group. This difference is statistically significant. The incidence of brain tumours in rats of group 3 corresponds to that of the control group. The average size of the tumours was the same in all groups. In the brains of the rats that received zinc with the drinking-water up to the 180th day but without administration of a cancerogen immediately after birth (group 4) we could not find any tumour, neither after 180 nor after 380 days. Our results indicate a cocancerogenic (promotion) effect of zinc in experimental neurooncogenesis of the rat. PMID:6466053

  13. Carotenoporphyrins as selective photodiagnostic agents for tumours.

    PubMed Central

    Reddi, E.; Segalla, A.; Jori, G.; Kerrigan, P. K.; Liddell, P. A.; Moore, A. L.; Moore, T. A.; Gust, D.

    1994-01-01

    The covalent binding of a carotene moiety to one phenyl ring and meso-tetraphenyl-substituted porphyrins (see Figure 1) efficiently quenches the photosensitising activity of the porphyrin while a relatively large yield of fluorescence emission around 650 nm is retained. Pharmacokinetic studies performed with two carotenoporphyrins (CPs) and the corresponding porphyrins (Ps) in Balb/c mice bearing an MS-2 fibrosarcoma show that the two Ps give a high selectivity of tumour localisation (tumour/peritumoral tissue ratios of dye concentration ranging between c. 30 and 90 at 24 h after injection of 4.2-8.4 mumol kg-1 in a Cremophor emulsion) and photosensitive tumour necrosis upon red light irradiation. For the same injected doses, the two CPs show no tumour-photosensitising activity even though they localise in the tumour in concentrations of the order of 10-40 micrograms g-1 at 24 h with tumour/peritumoral ratios larger than 10. Thus, the fluorescence emitted by these CPs in the tumour can be used for photodiagnostic purposes with no risk of skin photosensitisation. However, this approach is presently limited by the large accumulation and prolonged retention of the CPs in the liver and spleen. PMID:8286208

  14. Molecular response of 4T1-induced mouse mammary tumours and healthy tissues to zinc treatment.

    PubMed

    Sztalmachova, Marketa; Gumulec, Jaromir; Raudenska, Martina; Polanska, Hana; Holubova, Monika; Balvan, Jan; Hudcova, Kristyna; Knopfova, Lucia; Kizek, Rene; Adam, Vojtech; Babula, Petr; Masarik, Michal

    2015-04-01

    Breast cancer patients negative for the nuclear oestrogen receptor α have a particularly poor prognosis. Therefore, the 4T1 cell line (considered as a triple-negative model) was chosen to induce malignancy in mice. The aim of the present study was to assess if zinc ions, provided in excess, may significantly modify the process of mammary oncogenesis. Zn(II) ions were chosen because of their documented antitumour effects. Zn(II) is also known to induce the expression of metallothioneins (MT) and glutathion (GSH). A total dose of zinc sulphate per one gram of mouse weight used in the experiment was 0.15 mg. We studied the expression of MT1, MT2, TP53 and MTF-1 genes and also examined the effect of the tumour on antioxidant capacity. Tumour-free mice had significantly higher expression levels of the studied genes (p<0.003). Significant differences were also revealed in the gene expression between the tissues (p<0.001). The highest expression levels were observed in the liver. As compared to brain, lung and liver, significantly lower concentrations of MT protein were found in the primary tumour; an inverse trend was observed in the concentration of Zinc(II). In non-tumour mice, the amount of hepatic hydrosulphuryl groups significantly increased by the exposure to Zn(II), but the animals with tumour induction showed no similar trend. The primary tumour size of zinc-treated animals was 20% smaller (p=0.002); however, no significant effect on metastasis progression due to the zinc treatment was discovered. In conclusion, Zn(II) itself may mute the growth of primary breast tumours especially at their early stages. PMID:25672434

  15. Classification in Australia.

    ERIC Educational Resources Information Center

    McKinlay, John

    Despite some inroads by the Library of Congress Classification and short-lived experimentation with Universal Decimal Classification and Bliss Classification, Dewey Decimal Classification, with its ability in recent editions to be hospitable to local needs, remains the most widely used classification system in Australia. Although supplemented at…

  16. Purine-phosphoribosyltransferase activities in rat and mouse tissues and in Ehrlich ascites-tumour cells.

    PubMed

    Murray, A W

    1966-09-01

    1. The activities of adenine phosphoribosyltransferase and hypoxanthine phosphoribosyltransferase in extracts of rat and mouse liver, brain, spleen, heart and kidney, of rat bone marrow and of Ehrlich ascites-tumour cells have been measured. The specific activity of adenine phosphoribosyltransferase in tumour cells (3mmu-moles of nucleotide formed/min./mg. of protein) was between 15 and 60 times the activity of any mouse tissue examined. Hypoxanthine-phosphoribosyltransferase activity was greater in extracts of tumour cells than in mouse tissues, but the difference was not great. 2. The specific activities of both adenine phosphoribosyltransferase and hypoxanthine phosphoribosyltransferase in ascites-tumour cells decreased respectively by 57% and 36% 2 days after the cells had been inoculated into mice. After 4 days of tumour growth the specific activities of both enzymes increased, reaching a maximum at 10 days. 3. The activity of adenine phosphoribosyltransferase in rat-liver extracts increased steadily up to 4 days after partial hepatectomy, and was still above the control value after 14 days. Hypoxanthine-phosphoribosyltransferase activity in extracts of regenerating rat liver did not increase until the second day after operation and had begun to decrease by the fourth day. 4. From the results it was concluded that adenine phosphoribosyltransferase and hypoxanthine phosphoribosyltransferase may be physiologically important enzymes in rapidly growing tissues, and that inhibitors of the former enzyme have potential value in chemotherapy. PMID:16742414

  17. Decreased FOXJ1 expression and its ciliogenesis programme in aggressive ependymoma and choroid plexus tumours.

    PubMed

    Abedalthagafi, Malak S; Wu, Michael P; Merrill, Parker H; Du, Ziming; Woo, Terri; Sheu, Shu-Hsien; Hurwitz, Shelley; Ligon, Keith L; Santagata, Sandro

    2016-03-01

    Well-differentiated human cancers share transcriptional programmes with the normal tissue counterparts from which they arise. These programmes broadly influence cell behaviour and function and are integral modulators of malignancy. Here, we show that the master regulator of motile ciliogenesis, FOXJ1, is highly expressed in cells along the ventricular surface of the human brain. Strong expression is present in cells of the ependyma and the choroid plexus as well as in a subset of cells residing in the subventricular zone. Expression of FOXJ1 and its transcriptional programme is maintained in many well-differentiated human tumours that arise along the ventricle, including low-grade ependymal tumours and choroid plexus papillomas. Anaplastic ependymomas as well as choroid plexus carcinomas show decreased FOXJ1 expression and its associated ciliogenesis programme genes. In ependymomas and choroid plexus tumours, reduced expression of FOXJ1 and its ciliogenesis programme are markers of poor outcome and are therefore useful biomarkers for assessing these tumours. Transitions in ciliogenesis define distinct differentiation states in ependymal and choroid plexus tumours with important implications for patient care. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. PMID:26690880

  18. The prophylaxis of nonindustrial urothelial tumours

    PubMed Central

    Mount, Balfour M.

    1973-01-01

    Present knowledge concerning carcinogenesis and the natural history of urothelial tumours precludes firm conclusions relative to nonindustrial prophylaxis. However, a number of measures are consistent with current data and may be instituted for those patients with a demonstrated propensity to urothelial tumours. Their acceptability is based on the lack of associated toxicity for the patient. These measures include the elimination of significant infection, cigarettes, artificial sweeteners, analgesic abuse and coffee, the administration of vitamins C and B6, and in selected cases, the use of thiotepa. It is emphasized that the merit of these steps in altering the natural history of urothelial tumours is uncertain. PMID:4197537

  19. Female adnexal tumour of probable Wolffian origin.

    PubMed Central

    Sivathondan, Y; Salm, R; Hughesdon, P E; Faccini, J M

    1979-01-01

    Two further cases of 'female adnexal tumour of probable Wolffian origin' are described Both were retroperitoneal and presented a unique histology of uniformly close-packed bland spaces. solid islands, cords, and diffuse areas. A small hamartoma in a female fetus, part of which resembled the tumours, was traced to an area of near apposition with some paroophoron canals, providing further evidence of a Wolffian origin. The literature of this and some other putative Wolffian tumours is briefly reviewed, and the relation to rete adenomas is discussed. Images Fig. 2 Fig. 3 Fig. 1 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:469017

  20. Iodine-123 alpha-methyl tyrosine single-photon emission tomography of cerebral gliomas: standardised evaluation of tumour uptake and extent.

    PubMed

    Weckesser, M; Griessmeier, M; Schmidt, D; Sonnenberg, F; Ziemons, K; Kemna, L; Holschbach, M; Langen, K; Müller-Gärtner, H

    1998-02-01

    Single-photon emission tomography (SPET) with the amino acid analogue l-3-[123I]iodo-alpha-methyl tyrosine (IMT) is helpful in the diagnosis and monitoring of cerebral gliomas. Radiolabelled amino acids seem to reflect tumour infiltration more specifically than conventional methods like magnetic resonance imaging and computed tomography. Automatic tumour delineation based on maximal tumour uptake may cause an overestimation of mean tumour uptake and an underestimation of tumour extension in tumours with circumscribed peaks. The aim of this study was to develop a program for tumour delineation and calculation of mean tumour uptake which takes into account the mean background activity and is thus optimised to the problem of tumour definition in IMT SPET. Using the frequency distribution of pixel intensities of the tomograms a program was developed which automatically detects a reference brain region and draws an isocontour region around the tumour taking into account mean brain radioactivity. Tumour area and tumour/brain ratios were calculated. A three-compartment phantom was simulated to test the program. The program was applied to IMT SPET studies of 20 patients with cerebral gliomas and was compared to the results of manual analysis by three different investigators. Activity ratios and chamber extension of the phantom were correctly calculated by the automatic analysis. A method based on image maxima alone failed to determine chamber extension correctly. Manual region of interest analysis in patient studies resulted in a mean inter-observer standard deviation of 8.7% +/ -6.1% (range 2.7% -25.0%). The mean value of the results of the manual analysis showed a significant correlation to the results of the automatic analysis (r = 0.91, P<0. 0001 for the uptake ratio; r = 0.87, P<0.0001 for the tumour area). We conclude that the algorithm proposed simplifies the calculation of uptake ratios and may be used for observer-independent evaluation of IMT SPET studies. Three-dimensional tumour recognition and transfer to co-registered morphological images based on this program may be useful for the planning of surgical and radiation treatment. PMID:9473263

  1. Exceptional sensitivity of testicular germ cell tumour cell lines to the new anti-cancer agent, temozolomide.

    PubMed Central

    Pera, M. F.; Köberle, B.; Masters, J. R.

    1995-01-01

    Metastatic testicular germ cell tumours are cured in approximately 85% of patients using cisplatin-based combination chemotherapy. Patients who fail to respond have a poor prognosis, and there is a need for more effective treatments for cisplatin-resistant disease. In this study, it is shown that two of four cell lines derived from human non-seminomatous testicular germ cell tumours are exceptionally sensitive to temozolomide, a new imidazotetrazine which can cross the blood-brain barrier in mice. In addition, three pairs of cisplatin-resistant sublines show little cross-resistance to temozolomide. These data suggest that temozolomide might have activity against non-seminomatous testicular germ cell tumours which have relapsed following cisplatin-containing chemotherapy, and could have a role in the treatment of patients with metastatic lesions in the brain. PMID:7734313

  2. Remote Sensing Information Classification

    NASA Technical Reports Server (NTRS)

    Rickman, Douglas L.

    2008-01-01

    This viewgraph presentation reviews the classification of Remote Sensing data in relation to epidemiology. Classification is a way to reduce the dimensionality and precision to something a human can understand. Classification changes SCALAR data into NOMINAL data.

  3. Classification and knowledge

    NASA Technical Reports Server (NTRS)

    Kurtz, Michael J.

    1989-01-01

    Automated procedures to classify objects are discussed. The classification problem is reviewed, and the relation of epistemology and classification is considered. The classification of stellar spectra and of resolved images of galaxies is addressed.

  4. Primary malignant tumours of the duodenum.

    PubMed

    Nix, G A; Wilson, J H; Dees, J

    1985-04-01

    The clinical and radiological findings in 19 patients with primary duodenal malignancy are described. Weight loss, abdominal pain, nausea and vomiting were the main symptoms. Diagnosis was made by endoscopy or ERCP (71%) or by barium studies (68%). In retrospect the tumour was visible in 97% of the studies. Tumour growth was longitudinal, circular or spiral, the inner curvature being involved over a greater length than the outer curvature. Exophytic tumour growth, involvement of the papilla of Vater, malignant spikes, transient, non-constant tumour image, skip lesions and ulceration were often seen. Mean survival time was 18 months from start of symptoms in 10 inoperable patients, and 24 months in 9 patients undergoing resection. PMID:2986213

  5. Dentigerous Cyst Associated with Adenomatoid Odontogenic Tumour

    PubMed Central

    Majumdar, Sumit; Uppala, Divya; Talasila, Sunil; Babu, Mahesh

    2015-01-01

    Adenomatoid odontogenic tumour (AOT), a tumour composed of odontogenic epithelium, is an uncommon tumour of odontogenic origin that accounts for only 2.2- 7.1% of all odontogenic tumours. Very few cases of AOT associated with Dentigerous cyst (DC) have been reported till date, most cases are in females and have a striking tendency to occur in the anterior maxilla. The present case is that of a 14-year-old female who revealed a large radiolucent lesion associated with the crown of an unerupted canine located in the left maxillary anterior region. The microscopic examination revealed the presence of AOT in the fibrous capsule of a DC. In this paper, we describe the importance of grossing, sectioning and complete examination of the slide to diagnose such hybrid lesions. PMID:26155575

  6. Imaging tumour hypoxia with positron emission tomography.

    PubMed

    Fleming, I N; Manavaki, R; Blower, P J; West, C; Williams, K J; Harris, A L; Domarkas, J; Lord, S; Baldry, C; Gilbert, F J

    2015-01-20

    Hypoxia, a hallmark of most solid tumours, is a negative prognostic factor due to its association with an aggressive tumour phenotype and therapeutic resistance. Given its prominent role in oncology, accurate detection of hypoxia is important, as it impacts on prognosis and could influence treatment planning. A variety of approaches have been explored over the years for detecting and monitoring changes in hypoxia in tumours, including biological markers and noninvasive imaging techniques. Positron emission tomography (PET) is the preferred method for imaging tumour hypoxia due to its high specificity and sensitivity to probe physiological processes in vivo, as well as the ability to provide information about intracellular oxygenation levels. This review provides an overview of imaging hypoxia with PET, with an emphasis on the advantages and limitations of the currently available hypoxia radiotracers. PMID:25514380

  7. Stromal Claudin14-Heterozygosity, but Not Deletion, Increases Tumour Blood Leakage without Affecting Tumour Growth

    PubMed Central

    Baker, Marianne; Reynolds, Louise E.; Robinson, Stephen D.; Lees, Delphine M.; Parsons, Maddy; Elia, George; Hodivala-Dilke, Kairbaan

    2013-01-01

    The maintenance of endothelial cell-cell junctions is vital for the control of blood vessel leakage and is known to be important in the growth and maturation of new blood vessels during angiogenesis. Here we have investigated the role of a tight junction molecule, Claudin14, in tumour blood vessel leakage, angiogenesis and tumour growth. Using syngeneic tumour models our results showed that genetic ablation of Claudin14 was not sufficient to affect tumour blood vessel morphology or function. However, and surprisingly, Claudin14-heterozygous mice displayed several blood vessel-related phenotypes including: disruption of ZO-1-positive cell-cell junctions in tumour blood vessels; abnormal distribution of basement membrane laminin around tumour blood vessels; increased intratumoural leakage and decreased intratumoural hypoxia. Additionally, although total numbers of tumour blood vessels were increased in Claudin14-heterozygous mice, and in VEGF-stimulated angiogenesis ex vivo, the number of lumenated vessels was not changed between genotypes and this correlated with no difference in syngeneic tumour growth between wild-type, Claudin14-heterozygous and Claudin14-null mice. Lastly, Claudin14-heterozygosity, but not complete deficiency, also enhanced endothelial cell proliferation significantly. These data establish a new role for Claudin14 in the regulation of tumour blood vessel integrity and angiogenesis that is evident only after the partial loss of this molecule in Claudin14-heterozyous mice but not in Claudin14-null mice. PMID:23675413

  8. CT appearance of primary peritoneal serous borderline tumour: a rare epithelial tumour of the peritoneum

    PubMed Central

    Go, H S; Hong, H S; Kim, J W; Woo, J Y

    2012-01-01

    Primary peritoneal serous borderline tumour (PPSBT) is a rare epithelial neoplasm which is histologically identical to serous borderline tumour of the ovary. PPSBT is distinguishable from primary peritoneal serous carcinoma because the tumour cells do not invade the underlying tissue and affected patients have a good prognosis. We report the CT findings of surgically proven PPSBT in which multiple peritoneal cysts were seen. Although rare, PPSBT should be considered in the differential diagnosis of primary peritoneal tumours. Since the prognosis of the disease is good, conservation of the uterus and ovaries should be a consideration in young female patients during surgery. PMID:22190758

  9. Influence of tumour micro-environment heterogeneity on therapeutic response.

    PubMed

    Junttila, Melissa R; de Sauvage, Frederic J

    2013-09-19

    Tumour formation involves the co-evolution of neoplastic cells together with extracellular matrix, tumour vasculature and immune cells. Successful outgrowth of tumours and eventual metastasis is not determined solely by genetic alterations in tumour cells, but also by the fitness advantage such mutations confer in a given environment. As fitness is context dependent, evaluating tumours as complete organs, and not simply as masses of transformed epithelial cells, becomes paramount. The dynamic tumour topography varies drastically even throughout the same lesion. Heterologous cell types within tumours can actively influence therapeutic response and shape resistance. PMID:24048067

  10. Keratocystic odontogenic tumour: systematic review

    PubMed Central

    MacDonald-Jankowski, D S

    2011-01-01

    Objectives The aim of this review is to evaluate the principal clinical and conventional radiographic features of non-syndromic keratocystic odontogenic tumour (KCOT) by systematic review (SR), and to compare the frequencies between four global groups. Methods The databases searched were the PubMed interface of Medline and LILACS. Only those reports of KCOTs that occurred in a series of consecutive cases, in the reporting authors' caseload, were considered. Results 51 reports, of 49 series of cases, were included in the SR. 11 SR-included series were in languages other than English. KCOTs affected males more frequently and were three times more prevalent in the mandible. Although the mean age at first presentation was 37 years, the largest proportion of cases first presented in the third decade. The main symptom was swelling. Over a third were found incidentally. Nearly two-thirds displayed buccolingual expansion. Over a quarter of cases recurred. Only a quarter of all SR-included reported series of cases included details of at least one radiological feature. The East Asian global group presented significantly as well-defined, even corticated, multilocular radiolucencies with buccolingual expansion. The KCOTs affecting the Western global group significantly displayed an association with unerupted teeth. Conclusions Long-term follow-up of large series that would have revealed detailed radiographic description and long-term outcomes of non-syndromic KCOT was lacking. PMID:21159911

  11. Typical bronchial carcinoid tumour presenting as pneumomediastinum

    PubMed Central

    Zahid, M; Shafiq, I; Albon, L; Kause, J

    2011-01-01

    The authors present a case of a 44-year-old man who presented with acute onset shortness of breath. He had severe subcutaneous emphysema and his chest x-ray and CT scan confirmed presence of air in mediastinum. Rigid bronchoscopy revealed a bronchial tumour which was proven to be a carcinoid on histology. Patient recovered following the surgical excision of the tumour. PMID:22696668

  12. Diagnostic value of MRI for odontogenic tumours

    PubMed Central

    Fujita, M; Matsuzaki, H; Yanagi, Y; Hara, M; Katase, N; Hisatomi, M; Unetsubo, T; Konouchi, H; Nagatsuka, H; Asaumi, J-I

    2013-01-01

    Objectives: To evaluate the diagnostic value of MRI for odontogenic tumours. Materials and methods: 51 patients with odontogenic tumours were subjected to pre-operative MRI examinations. For tumours with liquid components, i.e. ameloblastomas and keratocystic odontogenic tumours (KCOTs), the signal intensity (SI) uniformity of their cystic components (U?) was calculated and then their U? values were compared. For tumours with solid components that had been examined using dynamic contrast-enhanced MRI (DCE-MRI), their CImax (maximum contrast index), Tmax (the time when CImax occurred), CIpeak (CImax?×?0.90), Tpeak (the time when CIpeak occurred) and CI300 (i.e. the CI observed at 300?s after contrast medium injection) values were determined from CI curves. We then classified the odontogenic tumours according to their DCE-MRI parameters. Results: Significant differences between the U? values of the ameloblastomas and KCOT were observed on T1 weighted images, T2 weighted images and short TI inversion recovery images. Depending on their DCE-MRI parameters, we classified the odontogenic tumours into the following five types: Type A, CIpeak?>?2.0 and Tpeak??2.0 and Tmax??2.0 and Tmax?>?600?s; Type E, CI300??600?s. Conclusion: Cystic component SI uniformity was found to be useful for differentiating between ameloblastomas and KCOT. However, the DCE-MRI parameters of odontogenic tumours, except for odontogenic fibromas and odontogenic myxomas, contributed little to their differential diagnosis. PMID:23468124

  13. Intramuscular Hibernoma: A Rare Tumour in Buttock

    PubMed Central

    Naik, Reena; Kushwaha, Anil KU; Agrawal, P.C.

    2015-01-01

    Hibernomas are benign tumours of brown fat that does not recur after complete excision. These tumours are found most often in adults and most commonly in thigh. Four morphologic variants of hibernoma are identified: typical, myxoid, spindle cell, and lipoma-like. The most common histologic type is typical variant. In this report, we present the clinical, morphological features and discuss the differential diagnosis of a typical variant of intramuscular hibernoma. PMID:26266129

  14. Epithelial odontogenic tumours in domestic animals.

    PubMed

    Walsh, K M; Denholm, L J; Cooper, B J

    1987-09-01

    Epithelial odontogenic tumours are uncommon, poorly understood and often difficult to diagnose, oral neoplasms. Dental organ pre-ameloblasts and basal lamina induce development of mesenchymal cells into odontoblasts, which produce dentin and induce pre-ameloblasts to mature into secretory ameloblasts. These reciprocal sequential inductive interactions between dental epithelium and mesenchyme form the basis for classifying epithelial odontogenic tumours. There are three tumours classified as non-inductive: ameloblastoma characterized by cords and islands of stellate reticulum with peripheral palisades of polarized columnar cells, adenomatoid ameloblastoma which has acini, rosettes and ducts of polarized columnar cells and stellate reticulum and calcifying epithelial odontogenic tumour which contains foci of Congo-red-positive material surrounded by pleomorphic polygonal epithelial cells. There are five tumours in which induction of mesenchymal tissue is evident: ameloblastic fibroma with characteristics of ameloblastoma plus proliferation of closely associated pulp-like mesenchyme; dentinoma consisting of masses of dentin, often with minimal cellular component; ameloblastic odontoma which contains palisaded epithelium and stellate reticulum as in ameloblastoma, as well as foci of dentin and/or enamel; complex odontoma which is a disorderly array of dentin, enamel, ameloblastic epithelium and odontoblasts; and compound odontoma containing denticles with well-organized tooth morphology. This paper reviews the embryogenesis of teeth and describes six types of epithelial odontogenic tumours in 13 animals. The literature concerning these tumours in nearly 250 animals is reviewed. The most commonly reported tumour is ameloblastoma and the species in which all types are most commonly reported is the dog. PMID:3316314

  15. Antenatally detected solid tumour of kidney

    PubMed Central

    Panda, Shasanka Shekhar; Mandelia, Ankur; Gupta, Devendra Kumar; Singh, Amit

    2014-01-01

    Congenital renal tumours are rare and usually benign. Polyhydramnios is the most common mode of presentation. Although most cases have been diagnosed postnatally, with advances in imaging technology, an increasing number of cases are being detected on antenatal scans. We describe a case of solid tumour of kidney detected in the second trimester of pregnancy and managed by surgery in the postnatal period. PMID:24526198

  16. Multiscale modelling and nonlinear simulation of vascular tumour growth

    PubMed Central

    Macklin, Paul; Anderson, Alexander R. A.; Chaplain, Mark A. J.; Cristini, Vittorio

    2011-01-01

    In this article, we present a new multiscale mathematical model for solid tumour growth which couples an improved model of tumour invasion with a model of tumour-induced angiogenesis. We perform nonlinear simulations of the multi-scale model that demonstrate the importance of the coupling between the development and remodeling of the vascular network, the blood flow through the network and the tumour progression. Consistent with clinical observations, the hydrostatic stress generated by tumour cell proliferation shuts down large portions of the vascular network dramatically affecting the flow, the subsequent network remodeling, the delivery of nutrients to the tumour and the subsequent tumour progression. In addition, extracellular matrix degradation by tumour cells is seen to have a dramatic affect on both the development of the vascular network and the growth response of the tumour. In particular, the newly developing vessels tend to encapsulate, rather than penetrate, the tumour and are thus less effective in delivering nutrients. PMID:18781303

  17. Host and tumour factors in cancer metastasis.

    PubMed

    Fidler, I J

    1990-10-01

    The process of cancer metastasis is sequential and selective and contains stochastic elements. The growth of metastases represents the endpoint of many lethal events that only few tumour cells survive. Primary tumours contain cells with heterogeneous metastatic properties, and the outcome of metastasis depends on the interplay of tumour cells with various host factors. Collectively, then, our studies and most data reported by others have led us to conclude that metastasis is a highly selective process regulated by a number of mechanisms. This belief is contrary to the once widely accepted notion that neoplastic dissemination is the ultimate expression of cellular anarchy. In fact, suggesting that cancer metastasis is a selective process is a more optimistic view in terms of cancer therapy than the one that contends that tumour dissemination is an entirely random event. A selective biological process is regulated by the interaction of tumour cells with their host, and these complex interactions can be studied and manipulated. A better understanding of the complexity of the processes of tumour evolution, progression, and metastasis should lead to improvements in the treatment of cancer. PMID:2124977

  18. Pulmonary adenocarcinoma: review of 106 cases and proposed new classification.

    PubMed Central

    Edwards, C W

    1987-01-01

    The gross and microscopic appearances of 106 resected pulmonary adenocarcinomas were reviewed and correlated with postoperative survival. Instead of using an established classification based on histological pattern, the tumours were categorised by cellular morphology and site as either parenchymal adenocarcinoma (67%), bronchial adenocarcinoma (13%), or adenocarcinoma of uncertain origin (20%). Despite their pleomorphic appearance parenchymal adenocarcinomas should be regarded as a single entity, derived from multipotential cells of the distal airway; bronchial adenocarcinomas were generally, but not invariably, associated with short postoperative survival; those tumours that could not be reclassified on histological grounds were large adenocarcinomas consisting mainly of mucus cells. Tumours of this type carry a poor prognosis. Images Fig 1 Fig 2 Fig 3 Fig 4 Fig 5 Figs 6a and b Fig 7 Fig 10 Fig 11 PMID:3818979

  19. Tumour nuclear oestrogen receptor beta 1 correlates inversely with parathyroid tumour weight.

    PubMed

    Haglund, Felix; Rosin, Gustaf; Nilsson, Inga-Lena; Juhlin, C Christofer; Pernow, Ylva; Norenstedt, Sophie; Dinets, Andrii; Larsson, Catharina; Hartman, Johan; Höög, Anders

    2015-03-01

    Primary hyperparathyroidism (PHPT) is a common endocrinopathy, frequently caused by a parathyroid adenoma, rarely by a parathyroid carcinoma that lacks effective oncological treatment. As the majority of cases are present in postmenopausal women, oestrogen signalling has been implicated in the tumourigenesis. Oestrogen receptor beta 1 (ERB1) and ERB2 have been recently identified in parathyroid adenomas, the former inducing genes coupled to tumour apoptosis. We applied immunohistochemistry and slide digitalisation to quantify nuclear ERB1 and ERB2 in 172 parathyroid adenomas, atypical adenomas and carcinomas, and ten normal parathyroid glands. All the normal parathyroid glands expressed ERB1 and ERB2. The majority of tumours expressed ERB1 (70.6%) at varying intensities, and ERB2 (96.5%) at strong intensities. Parathyroid carcinomas expressed ERB1 in three out of six cases and ERB2 in five out of six cases. The intensity of tumour nuclear ERB1 staining significantly correlated inversely with tumour weight (P=0.011), and patients whose tumours were classified as ERB1-negative had significantly greater tumour weight as well as higher serum calcium (P=0.002) and parathyroid hormone levels (P=0.003). Additionally, tumour nuclear ERB1 was not expressed differentially with respect to sex or age of the patient. Levels of tumour nuclear ERB2 did not correlate with clinical characteristics. In conclusion, decreased ERB1 immunoreactivity is associated with increased tumour weight in parathyroid adenomas. Given the previously reported correlation with tumour-suppressive signalling, selective oestrogen receptor modulation (SERMs) may play a role in the treatment of parathyroid carcinomas. Future studies of SERMs and oestrogen treatment in PHPT should consider tumour weight as a potential factor in pharmacological responsiveness. PMID:25648860

  20. Tumour nuclear oestrogen receptor beta 1 correlates inversely with parathyroid tumour weight

    PubMed Central

    Haglund, Felix; Rosin, Gustaf; Nilsson, Inga-Lena; Juhlin, C Christofer; Pernow, Ylva; Norenstedt, Sophie; Dinets, Andrii; Larsson, Catharina; Hartman, Johan; Höög, Anders

    2015-01-01

    Primary hyperparathyroidism (PHPT) is a common endocrinopathy, frequently caused by a parathyroid adenoma, rarely by a parathyroid carcinoma that lacks effective oncological treatment. As the majority of cases are present in postmenopausal women, oestrogen signalling has been implicated in the tumourigenesis. Oestrogen receptor beta 1 (ERB1) and ERB2 have been recently identified in parathyroid adenomas, the former inducing genes coupled to tumour apoptosis. We applied immunohistochemistry and slide digitalisation to quantify nuclear ERB1 and ERB2 in 172 parathyroid adenomas, atypical adenomas and carcinomas, and ten normal parathyroid glands. All the normal parathyroid glands expressed ERB1 and ERB2. The majority of tumours expressed ERB1 (70.6%) at varying intensities, and ERB2 (96.5%) at strong intensities. Parathyroid carcinomas expressed ERB1 in three out of six cases and ERB2 in five out of six cases. The intensity of tumour nuclear ERB1 staining significantly correlated inversely with tumour weight (P=0.011), and patients whose tumours were classified as ERB1-negative had significantly greater tumour weight as well as higher serum calcium (P=0.002) and parathyroid hormone levels (P=0.003). Additionally, tumour nuclear ERB1 was not expressed differentially with respect to sex or age of the patient. Levels of tumour nuclear ERB2 did not correlate with clinical characteristics. In conclusion, decreased ERB1 immunoreactivity is associated with increased tumour weight in parathyroid adenomas. Given the previously reported correlation with tumour-suppressive signalling, selective oestrogen receptor modulation (SERMs) may play a role in the treatment of parathyroid carcinomas. Future studies of SERMs and oestrogen treatment in PHPT should consider tumour weight as a potential factor in pharmacological responsiveness. PMID:25648860

  1. Microsatellite Instability Use in Mismatch Repair Gene Sequence Variant Classification

    PubMed Central

    Thompson, Bryony A.; Spurdle, Amanda B.

    2015-01-01

    Inherited mutations in the DNA mismatch repair genes (MMR) can cause MMR deficiency and increased susceptibility to colorectal and endometrial cancer. Microsatellite instability (MSI) is the defining molecular signature of MMR deficiency. The clinical classification of identified MMR gene sequence variants has a direct impact on the management of patients and their families. For a significant proportion of cases sequence variants of uncertain clinical significance (also known as unclassified variants) are identified, constituting a challenge for genetic counselling and clinical management of families. The effect on protein function of these variants is difficult to interpret. The presence or absence of MSI in tumours can aid in determining the pathogenicity of associated unclassified MMR gene variants. However, there are some considerations that need to be taken into account when using MSI for variant interpretation. The use of MSI and other tumour characteristics in MMR gene sequence variant classification will be explored in this review. PMID:25831438

  2. Brain herniation

    MedlinePLUS

    ... herniation; Uncal herniation; Subfalcine herniation; Tonsillar herniation; Herniation - brain ... Brain herniation occurs when something inside the skull produces pressure that moves brain tissues. This is most ...

  3. The CHAT classification of stroke.

    PubMed Central

    Bernstein, E F; Browse, N L

    1989-01-01

    Current terminology for clinical episodes relating to stroke is inconsistent and unclear, does not permit inclusion of data regarding the location and magnitude of extracranial and intracerebral arterial disease, does not coincide with existing classifications in Europe, and characterizes a hemispheric entity only, as opposed to a global description including prior symptoms in both hemispheres. A new classification system (CHAT) has been designed to deal with these problems, including the current clinical presentation, historical clinical episodes, the site and pathologic type of arterial disease, and information regarding abnormalities of the brain. Using this system, a retrospective review of 480 consecutive carotid endarterectomies is presented, demonstrating the advantages of the CHAT classification. Data include a significant difference in the probability of survival after carotid endarterectomy for asymptomatic stenosis in patients with prior symptoms on the opposite side, as well as a significant difference in the probability of stroke-free survival between patients with amaurosis fugax and those with prior carotid cortical symptoms (TIAs) as the presenting clinical condition. The CHAT classification is suggested as a significant advance in the reporting of all surgical cerebrovascular disease experience, and has particular implications for the current randomized trials between medical and surgical therapy for carotid artery disease. PMID:2916868

  4. Tumour-induced neoneurogenesis and perineural tumour growth: a mathematical approach

    NASA Astrophysics Data System (ADS)

    Lolas, Georgios; Bianchi, Arianna; Syrigos, Konstantinos N.

    2016-02-01

    It is well-known that tumours induce the formation of a lymphatic and a blood vasculature around themselves. A similar but far less studied process occurs in relation to the nervous system and is referred to as neoneurogenesis. The relationship between tumour progression and the nervous system is still poorly understood and is likely to involve a multitude of factors. It is therefore relevant to study tumour-nerve interactions through mathematical modelling: this may reveal the most significant factors of the plethora of interacting elements regulating neoneurogenesis. The present work is a first attempt to model the neurobiological aspect of cancer development through a system of differential equations. The model confirms the experimental observations that a tumour is able to promote nerve formation/elongation around itself, and that high levels of nerve growth factor and axon guidance molecules are recorded in the presence of a tumour. Our results also reflect the observation that high stress levels (represented by higher norepinephrine release by sympathetic nerves) contribute to tumour development and spread, indicating a mutually beneficial relationship between tumour cells and neurons. The model predictions suggest novel therapeutic strategies, aimed at blocking the stress effects on tumour growth and dissemination.

  5. Tumour-induced neoneurogenesis and perineural tumour growth: a mathematical approach

    PubMed Central

    Lolas, Georgios; Bianchi, Arianna; Syrigos, Konstantinos N.

    2016-01-01

    It is well-known that tumours induce the formation of a lymphatic and a blood vasculature around themselves. A similar but far less studied process occurs in relation to the nervous system and is referred to as neoneurogenesis. The relationship between tumour progression and the nervous system is still poorly understood and is likely to involve a multitude of factors. It is therefore relevant to study tumour-nerve interactions through mathematical modelling: this may reveal the most significant factors of the plethora of interacting elements regulating neoneurogenesis. The present work is a first attempt to model the neurobiological aspect of cancer development through a system of differential equations. The model confirms the experimental observations that a tumour is able to promote nerve formation/elongation around itself, and that high levels of nerve growth factor and axon guidance molecules are recorded in the presence of a tumour. Our results also reflect the observation that high stress levels (represented by higher norepinephrine release by sympathetic nerves) contribute to tumour development and spread, indicating a mutually beneficial relationship between tumour cells and neurons. The model predictions suggest novel therapeutic strategies, aimed at blocking the stress effects on tumour growth and dissemination. PMID:26861829

  6. Tumour-induced neoneurogenesis and perineural tumour growth: a mathematical approach.

    PubMed

    Lolas, Georgios; Bianchi, Arianna; Syrigos, Konstantinos N

    2016-01-01

    It is well-known that tumours induce the formation of a lymphatic and a blood vasculature around themselves. A similar but far less studied process occurs in relation to the nervous system and is referred to as neoneurogenesis. The relationship between tumour progression and the nervous system is still poorly understood and is likely to involve a multitude of factors. It is therefore relevant to study tumour-nerve interactions through mathematical modelling: this may reveal the most significant factors of the plethora of interacting elements regulating neoneurogenesis. The present work is a first attempt to model the neurobiological aspect of cancer development through a system of differential equations. The model confirms the experimental observations that a tumour is able to promote nerve formation/elongation around itself, and that high levels of nerve growth factor and axon guidance molecules are recorded in the presence of a tumour. Our results also reflect the observation that high stress levels (represented by higher norepinephrine release by sympathetic nerves) contribute to tumour development and spread, indicating a mutually beneficial relationship between tumour cells and neurons. The model predictions suggest novel therapeutic strategies, aimed at blocking the stress effects on tumour growth and dissemination. PMID:26861829

  7. Tumour resistance to cisplatin: a modelling approach

    NASA Astrophysics Data System (ADS)

    Marcu, L.; Bezak, E.; Olver, I.; van Doorn, T.

    2005-01-01

    Although chemotherapy has revolutionized the treatment of haematological tumours, in many common solid tumours the success has been limited. Some of the reasons for the limitations are: the timing of drug delivery, resistance to the drug, repopulation between cycles of chemotherapy and the lack of complete understanding of the pharmacokinetics and pharmacodynamics of a specific agent. Cisplatin is among the most effective cytotoxic agents used in head and neck cancer treatments. When modelling cisplatin as a single agent, the properties of cisplatin only have to be taken into account, reducing the number of assumptions that are considered in the generalized chemotherapy models. The aim of the present paper is to model the biological effect of cisplatin and to simulate the consequence of cisplatin resistance on tumour control. The 'treated' tumour is a squamous cell carcinoma of the head and neck, previously grown by computer-based Monte Carlo techniques. The model maintained the biological constitution of a tumour through the generation of stem cells, proliferating cells and non-proliferating cells. Cell kinetic parameters (mean cell cycle time, cell loss factor, thymidine labelling index) were also consistent with the literature. A sensitivity study on the contribution of various mechanisms leading to drug resistance is undertaken. To quantify the extent of drug resistance, the cisplatin resistance factor (CRF) is defined as the ratio between the number of surviving cells of the resistant population and the number of surviving cells of the sensitive population, determined after the same treatment time. It is shown that there is a supra-linear dependence of CRF on the percentage of cisplatin-DNA adducts formed, and a sigmoid-like dependence between CRF and the percentage of cells killed in resistant tumours. Drug resistance is shown to be a cumulative process which eventually can overcome tumour regression leading to treatment failure.

  8. Frequent Promoter Hypermethylation of the APC and RASSF1A Tumour Suppressors in Parathyroid Tumours

    PubMed Central

    Juhlin, C. Christofer; Kiss, Nimrod B.; Villablanca, Andrea; Haglund, Felix; Nordenström, Jörgen; Höög, Anders; Larsson, Catharina

    2010-01-01

    Background Parathyroid adenomas constitute the most common entity in primary hyperparathyroidism, and although recent advances have been made regarding the underlying genetic cause of these lesions, very little data on epigenetic alterations in this tumour type exists. In this study, we have determined the levels of promoter methylation regarding the four tumour suppressor genes APC, RASSF1A, p16INK4A and RAR-? in parathyroid adenomas. In addition, the levels of global methylation were assessed by analyzing LINE-1 repeats. Methodology/Principal Findings The sample collection consisted of 55 parathyroid tumours with known HRPT2 and/or MEN1 genotypes. Using Pyrosequencing analysis, we demonstrate APC promoter 1A and RASSF1A promoter hypermethylation in the majority of parathyroid tumours (71% and 98%, respectively). Using TaqMan qRT-PCR, all tumours analyzed displayed lower RASSF1A mRNA expression and higher levels of total APC mRNA than normal parathyroid, the latter of which was largely conferred by augmented APC 1B transcription levels. Hypermethylation of p16INK4A was demonstrated in a single adenoma, whereas RAR-? hypermethylation was not observed in any sample. Moreover, based on LINE-1 analyses, parathyroid tumours exhibited global methylation levels within the range of non-neoplastic parathyroid tissues. Conclusions/Significance The results demonstrate that APC and RASSF1A promoter hypermethylation are common events in parathyroid tumours. While RASSF1A mRNA levels were found downregulated in all tumours investigated, APC gene expression was retained through APC 1B mRNA levels. These findings suggest the involvement of the Ras signaling pathway in parathyroid tumorigenesis. Additionally, in contrast to most other human cancers, parathyroid tumours were not characterized by global hypomethylation, as parathyroid tumours exhibited LINE-1 methylation levels similar to that of normal parathyroid tissues. PMID:20208994

  9. An Ectopic ACTH Secreting Metastatic Parotid Tumour

    PubMed Central

    Dacruz, Thomas; Kalhan, Atul; Rashid, Majid; Obuobie, Kofi

    2016-01-01

    A 60-year old woman presented with features of Cushing's syndrome (CS) secondary to an ectopic adrenocorticotropic hormone (ACTH) secreting metastatic parotid tumour 3 years after excision of the original tumour. She subsequently developed fatal intestinal perforation and unfortunately died despite best possible medical measures. Ectopic ACTH secretion accounts for 5–10% of all patients presenting with ACTH dependent hypercortisolism; small cell carcinoma of lung (SCLC) and neuroendocrine tumours (NET) account for the majority of such cases. Although there are 4 previous case reports of ectopic ACTH secreting salivary tumours in literature, to our knowledge this is the first published case report in which the CS developed after 3 years of what was deemed as a successful surgical excision of primary salivary tumour. Our patient initially had nonspecific symptoms which may have contributed to a delay in diagnosis. Perforation of sigmoid colon is a recognised though underdiagnosed complication associated with steroid therapy and hypercortisolism. This case demonstrates the challenges faced in diagnosis as well as management of patients with CS apart from the practical difficulties faced while trying to identify source of ectopic ACTH. PMID:26904316

  10. Localization of gastroenteropancreatic tumours by angiography.

    PubMed

    Doppman, J L; Jensen, R T

    1999-10-01

    Neuroendocrine tumours are seen on arteriography as diffusely enhancing masses without tumour vessels and without arteriovenous shunting. In 70 patients with surgically proven tumours, the sensitivity of angiography was 68% for extrapancreatic and 86% for hepatic lesions. Hepatic metastases have always been easier to demonstrate arteriographically than the primary tumour because of the absence of overlying bowel. Portal venous sampling is a sensitive technique for detecting functioning gastroenteropancreatic tumours. Sampling the small veins about the pancreatic head yielded a sensitivity of 62% but this is an invasive procedure in which considerable experience is required. Intra-arterial secretagogue, secretin for gastrinomas and calcium for insulinomas, selectively injected into the pancreatic and the hepatic arteries produce a diagnostic gastrin or insulin gradient respectively. The localization sensitivity of arterial stimulation with venous sampling is 77-89% for gastrinoma and 92% for pancreatic insulinoma. Recently, spiral CT in conjunction with selective intra-arterial rather than intravenous injection of contrast may increase the detection sensitivity of duodenal and pancreatic gastrinomas. PMID:10604123

  11. Primary pulmonary tumours of neurogenic origin.

    PubMed Central

    Roviaro, G; Montorsi, M; Varoli, F; Binda, R; Cecchetto, A

    1983-01-01

    Primary intrapulmonary neurogenic tumours are extremely rare. In a series of 1664 patients with pulmonary neoplasms observed during 1967-80 only four such tumours were identified (0.2%). All four patients underwent surgical excision. The histological diagnosis was benign neurilemmoma in three cases and malignant schwannoma in the fourth. The patients with neurilemmoma are alive and well four to 12 years after surgery, but the patient with malignant schwannoma died from metastatic spread of the tumour four months after surgery. No association with von Recklinghausen's disease was observed. Macroscopic and microscopic features generally lead to a correct diagnosis in benign types, but the histological diagnosis of malignant schwannoma may present some difficulties and requires the establishment of a definite origin in a nervous structure, identification of benign neurofibroma in different areas of the same tumour, and a high density of cells with appreciable pleomorphism, with mitosis and atypia. Benign tumours carry a good prognosis with little tendency to recur, but malignant schwannoma has a high invasive tendency and is associated with a low survival rate. Images PMID:6665754

  12. Improving tumour heterogeneity MRI assessment with histograms

    PubMed Central

    Just, N

    2014-01-01

    By definition, tumours are heterogeneous. They are defined by marked differences in cells, microenvironmental factors (oxygenation levels, pH, VEGF, VPF and TGF-?) metabolism, vasculature, structure and function that in turn translate into heterogeneous drug delivery and therapeutic outcome. Ways to estimate quantitatively tumour heterogeneity can improve drug discovery, treatment planning and therapeutic responses. It is therefore of paramount importance to have reliable and reproducible biomarkers of cancerous lesions' heterogeneity. During the past decade, the number of studies using histogram approaches increased drastically with various magnetic resonance imaging (MRI) techniques (DCE-MRI, DWI, SWI etc.) although information on tumour heterogeneity remains poorly exploited. This fact can be attributed to a poor knowledge of the available metrics and of their specific meaning as well as to the lack of literature references to standardised histogram methods with which surrogate markers of heterogeneity can be compared. This review highlights the current knowledge and critical advances needed to investigate and quantify tumour heterogeneity. The key role of imaging techniques and in particular the key role of MRI for an accurate investigation of tumour heterogeneity is reviewed with a particular emphasis on histogram approaches and derived methods. PMID:25268373

  13. Neuroendoscopic management of pineal region tumours.

    PubMed

    Ferrer, E; Santamarta, D; Garcia-Fructuoso, G; Caral, L; Rumià, J

    1997-01-01

    The management of pineal tumours remains controversial. During 1994 we treated four consecutive adults (16-44 yrs) harbouring a pineal tumour with a neuroendoscopic procedure. All of them presented with hydrocephalus. Pre-operative workup included cranial computerized tomography (CT), craniospinal magnetic resonance imaging (MRI) and serum levels of biological tumour markers. The endoscopic procedure consisted of a third ventriculostomy followed by biopsy with a flexible, steerable neuroendoscope. Histological diagnosis was achieved in three patients who no longer required a shunt device. Recorded complications were: bleeding during ventriculostomy that prevented us from obtaining a good sample for biopsy, short-term memory loss that cleared over a two-week period, and transient increase of pre-operative hemiparesis. Complications and morbidity are emphasized so as to be avoided with further technical experience. Neuroendoscopy affords a minimally invasive way of reaching three objectives by one-step surgery in the management of pineal region lesions: 1) CSF sample for analysis of tumour markers. 2) Treatment of hydrocephalus by third ventriculostomy. 3) Several biopsy specimens can be obtained identifying tumours which will require further open surgery or adjuvant radiation and/or chemotherapy. PMID:9059706

  14. The Nature and Classification of Ovarian Neoplasms

    PubMed Central

    Abell, M. R.

    1966-01-01

    The classification of ovarian neoplasms on a histogenetic basis according to presentday concepts of development and structure of the ovary is considered. There are four histogenetic categories of primary ovarian tumours: neoplasms of germ cell origin, neoplasms of celomic (germinal) epithelium and its derivatives, neoplasms of specialized gonadal stroma (sex cords and mesenchyme), and neoplasms of non-specialized gonadal stromal and heterotopic elements. In patients of all ages, 70% of ovarian neoplasms were of celomic epithelial origin, 16% of germ-cell origin, 5% of specialized gonadal stromal origin, and 9% arose from the non-specialized stroma and heterotopic elements. Before 20 years of age, 59% of ovarian neoplasms were of germ cell origin and before puberty they accounted for 90% of all ovarian tumours. The different structural types of neoplasms within the four categories are described. Accurate classification of ovarian neoplasms on a histogenetic basis is stressed if proper treatment is to be given and intelligent assessment of end results is to be made. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11Fig. 12Fig. 13Fig. 14Fig. 15Fig. 16Fig. 17Fig. 18Fig. 19Fig. 20Fig. 21Fig. 22Fig. 23Fig. 24Fig. 25Fig. 26Fig. 27Fig. 28Fig. 29Fig. 30 PMID:4286898

  15. [Carcinoid tumours of the lung and definition of the medico-legal term "lung cancer" used in the list of occupational disease in Germany--results of the German Mesothelioma Register].

    PubMed

    Neumann, V; Fischer, M; Tannapfel, A

    2008-09-01

    Carcinoid tumours are considered to be malignant epithelial tumours according to the recent WHO classification. This study is based on the examinations of tissue from 108 patients with carcinoid tumours. Our data agree with those of other studies: carcinoid tumours developed mainly in the right lung (40 %) and the lower lobe (30 %), mean age was 56 years, typical carcinoid tumours (74 %) predominated, comparatively high proportion of females (32 %), the mean latency period after asbestos exposure - assuming asbestos as one causal factor - was 35 years. A higher incidence of carcinoid tumours (1.3 %) in the collective of the mesothelioma register compared to the incidence in the collective of all lung carcinomas (1 - 2 %) was not observed. The increased pulmonary asbestos burden analysed in 26 % of patients is explained by the exposure-dependent selection of patients in the register. So far, no association between smoking habits or exposure to other, i. e., occupational pollutions and the development of carcinoid tumours could be established. In the list of occupational diseases (No. 4104) the term "lung cancer" is used without further specification. Thus the following question remains open for discussion: does the term "lung cancer" include carcinoid tumours such as malignant epithelial lung tumours, or is it restricted to the common subtypes such as small cell carcinoma, squamous cell carcinoma, adenocarcinoma, large cell carcinoma with regard to occupational disease and compensation? PMID:18473290

  16. Intracranial tumour haemorrhage following intravenous thrombolysis.

    PubMed

    Diehl, Christian; Haux, Daniel; Sahm, Felix; Unterberg, Andreas W; Beynon, Christopher

    2016-04-01

    Intravenous administration of thrombolytic agents is considered to be contraindicated in patients with intracranial neoplasms. However, only a single case of thrombolysis-related intracranial tumour haemorrhage has been reported to our knowledge and several studies have suggested that systemic thrombolysis can be safely carried out in these patients. Here we report a patient who developed haemorrhage into a previously unknown intracranial tumour following intravenous thrombolysis for acute myocardial ST-elevation infarction. Identification of abnormal tissue during surgical haematoma evacuation initiated histopathological examination which revealed meningioma World Health Organization Grade I. Intracranial tumours may represent the causative pathology in cases of thrombolysis-related intracranial haemorrhage and this should be considered in the treatment of these patients. PMID:26646504

  17. Surgery for locally aggressive bone tumours.

    PubMed

    Devitt, A; O'Sullivan, T; Kavanagh, M; Hurson, B J

    1996-01-01

    Treatment of 16 patients with aggressive benign bone tumours and one patient with a low grade malignancy with a combined regimen of cryosurgery, phenolization and acrylic cementation is reported. Patients were aged between 9 and 51 years and were treated by this method between the years 1986 and 1993. Minimal follow up was 13 months. The commonest histological diagnosis was giant cell tumour (7), followed by aneurysmal bone cyst (6), chondromyxoidfibroma (3) and low grade chondrosarcoma (1). Patients were assessed for functional outcome and local recurrence. On average 86 per cent of premorbid function was restored at follow up and there was one local recurrence (6.29 per cent). We conclude that this is a satisfactory method of gaining local control of these tumours. PMID:8990655

  18. Functional Brain Imaging

    PubMed Central

    2006-01-01

    Executive Summary Objective The objective of this analysis is to review a spectrum of functional brain imaging technologies to identify whether there are any imaging modalities that are more effective than others for various brain pathology conditions. This evidence-based analysis reviews magnetoencephalography (MEG), magnetic resonance spectroscopy (MRS), positron emission tomography (PET), and functional magnetic resonance imaging (fMRI) for the diagnosis or surgical management of the following conditions: Alzheimer’s disease (AD), brain tumours, epilepsy, multiple sclerosis (MS), and Parkinson’s disease (PD). Clinical Need: Target Population and Condition Alzheimer’s disease is a progressive, degenerative, neurologic condition characterized by cognitive impairment and memory loss. The Canadian Study on Health and Aging estimated that there will be 97,000 incident cases (about 60,000 women) of dementia (including AD) in Canada in 2006. In Ontario, there will be an estimated 950 new cases and 580 deaths due to brain cancer in 2006. Treatments for brain tumours include surgery and radiation therapy. However, one of the limitations of radiation therapy is that it damages tissue though necrosis and scarring. Computed tomography (CT) and magnetic resonance imaging (MRI) may not distinguish between radiation effects and resistant tissue, creating a potential role for functional brain imaging. Epilepsy is a chronic disorder that provokes repetitive seizures. In Ontario, the rate of epilepsy is estimated to be 5 cases per 1,000 people. Most people with epilepsy are effectively managed with drug therapy; but about 50% do not respond to drug therapy. Surgical resection of the seizure foci may be considered in these patients, and functional brain imaging may play a role in localizing the seizure foci. Multiple sclerosis is a progressive, inflammatory, demyelinating disease of the central nervous system (CNS). The cause of MS is unknown; however, it is thought to be due to a combination of etiologies, including genetic and environmental components. The prevalence of MS in Canada is 240 cases per 100,000 people. Parkinson’s disease is the most prevalent movement disorder; it affects an estimated 100,000 Canadians. Currently, the standard for measuring disease progression is through the use of scales, which are subjective measures of disease progression. Functional brain imaging may provide an objective measure of disease progression, differentiation between parkinsonian syndromes, and response to therapy. The Technology Being Reviewed Functional Brain Imaging Functional brain imaging technologies measure blood flow and metabolism. The results of these tests are often used in conjunction with structural imaging (e.g., MRI or CT). Positron emission tomography and MRS identify abnormalities in brain tissues. The former measures abnormalities through uptake of radiotracers in the brain, while the latter measures chemical shifts in metabolite ratios to identify abnormalities. The potential role of functional MRI (fMRI) is to identify the areas of the brain responsible for language, sensory and motor function (sensorimotor cortex), rather than identifying abnormalities in tissues. Magnetoencephalography measures magnetic fields of the electric currents in the brain, identifying aberrant activity. Magnetoencephalography may have the potential to localize seizure foci and to identify the sensorimotor cortex, visual cortex and auditory cortex. In terms of regulatory status, MEG and PET are licensed by Health Canada. Both MRS and fMRI use a MRI platform; thus, they do not have a separate licence from Health Canada. The radiotracers used in PET scanning are not licensed by Health Canada for general use but can be used through a Clinical Trials Application. Review Strategy The literature published up to September 2006 was searched in the following databases: MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, Cochrane Database of Systematic Reviews, CENTRAL, and International Network of Agencies for H

  19. The tumour suppressor C/EBP? inhibits FBXW7 expression and promotes mammary tumour metastasis

    PubMed Central

    Balamurugan, Kuppusamy; Wang, Ju-Ming; Tsai, Hsin-Hwa; Sharan, Shikha; Anver, Miriam; Leighty, Robert; Sterneck, Esta

    2010-01-01

    Inflammation and hypoxia are known to promote the metastatic progression of tumours. The CCAAT/enhancer-binding protein-? (C/EBP?, CEBPD) is an inflammatory response gene and candidate tumour suppressor, but its physiological role in tumourigenesis in vivo is unknown. Here, we demonstrate a tumour suppressor function of C/EBP? using transgenic mice overexpressing the Neu/Her2/ERBB2 proto-oncogene in the mammary gland. Unexpectedly, this study also revealed that C/EBP? is necessary for efficient tumour metastasis. We show that C/EBP? is induced by hypoxia in tumours in vivo and in breast tumour cells in vitro, and that C/EBP?-deficient cells exhibit reduced glycolytic metabolism and cell viability under hypoxia. C/EBP? supports CXCR4 expression. On the other hand, C/EBP? directly inhibits expression of the tumour suppressor F-box and WD repeat-domain containing 7 gene (FBXW7, FBW7, AGO, Cdc4), encoding an F-box protein that promotes degradation of the mammalian target of rapamycin (mTOR). Consequently, C/EBP? enhances mTOR/AKT/S6K1 signalling and augments translation and activity of hypoxia-inducible factor-1? (HIF-1?), which is necessary for hypoxia adaptation. This work provides new insight into the mechanisms by which metastasis-promoting signals are induced specifically under hypoxia. PMID:21076392

  20. Peripheral nerve tumours: 30-year experience in the surgical treatment.

    PubMed

    Gosk, Jerzy; Gutkowska, Olga; Mazurek, Piotr; Koszewicz, Magdalena; Zió?kowski, Piotr

    2015-07-01

    Peripheral nerve tumours are relatively rare type of soft tissue tumours. The aim of this work is to present our experience with surgical treatment of this type of lesions. Clinical material consists of 94 patients (56 females, 38 males), in whom 101 tumours deriving from peripheral nervous system were removed. The patients underwent surgical treatment between 1983 and 2012. Tumours occurred mainly in the upper extremity (72 tumours), less often in the lower extremity (25 tumours). Lesions developed in major peripheral nerves (51 tumours) and small nerve branches (50 tumours). The most common symptoms reported before surgery included presence of tumour mass (100 %), positive Hoffmann-Tinel sign (95.6 %) and paraesthesia (93.4 %). Less often sensory deficit (89.1 %) and pain (71.7 %) were observed. Motor deficit was the least common manifestation (41.3 %). Benign tumours prevailed in presented material (94 tumours). In 7 cases, malignant peripheral nerve sheath tumour (MPNST) was identified. As a result of surgical treatment in the group of tumours deriving from major peripheral nerves, in 87.8 % of the patients, pain relief was achieved; in 84 %, Hoffmann-Tinel sign was negative; and in 79 %, paraesthesia resolved. Sensory function improvement was observed in 51.2 % of the patients while motor function improved in 26.3 % of the patients. None of the patients experienced tumour relapse. In the group of tumours deriving from small nerve branches, 47 patients had no signs of tumour recurrence. One female patient diagnosed with MPNST suffered a relapse. Obtaining satisfactory results of peripheral nerve tumour treatment requires both careful differential diagnosis and well thought-out strategy at every stage of therapeutic management. PMID:25727458

  1. Sertoliform cystadenoma: a rare benign tumour of the rete testis

    PubMed Central

    2013-01-01

    Abstract Sertoliform cystadenoma of the rete testis represents an uncommon benign tumour. They appear in patients from 26 to 62 years of age. We describe a case of a 66-year-old man with a tumour in the area of the epididymal head. The tumour markers were not increased. Under the assumption of a malignant testicular tumour an inguinal orchiectomy was performed. The cut surface of this tumour was of grey/white color and showed small cysts. The tumour consisted of two compartments. The epithelial like tumour cells showed a sertoliform growth pattern and cystic dilatations. In between the tumour cells repeatedly actin expressing sclerotic areas could be recognized as the second tumour component. Proliferative activity was not increased. Immunohistochemically the tumour cells were positiv for inhibin, S-100, and CD 99. Alpha feto protein (AFP), human chorionic gonadotropin (ß-HCG) and placental alkaline phosphatase (PLAP) as well as synaptophysin, epithelial membrane antigene (EMA), and BCL-2 were not expressed. As far as we know this is the sixth reported case of this tumour. Because of the benign nature of this tumour the correct diagnosis is important for the intra- and postoperative management. Here we present a case of this rare tumour and discuss potential differential diagnosis. Virtual Slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1956026143857335 PMID:23406299

  2. Response and recovery kinetics of a solid tumour after irradiation.

    PubMed

    Rowley, R; Hopkins, H A; Betsill, W L; Ritenour, E R; Looney, W B

    1980-10-01

    The effects of local tumour radiation over the dose range 7.5-30 Gy on the growth and cell kinetics of rat hepatoma H-4-II-E have been investigated. A plot of growth delays against log surviving fraction was linear below a fraction of 0.03, but failed to extrapolate to the origin. Following a single dose of 15 Gy to the tumour, DNA-precursor incorporation, labelling and mitotic indices were depressed for 7 days. Tumour cellularity, measured as DNA/g tumour, was reduced and the rate of increase of total clonogenic cells slower than after complete tumour recovery. From Day 7 to Day 9 all indices of proliferation recovered to about control levels, clonogenic cell numbers increased more rapidly and tumour cellularity was restored. Repopulation of the tumour therefore appeared to take place mainly after Day 7. Incorporation of [3H]-TdR into tumour DNA reached twice the control values on Day 9. The rate of tumour growth accelerated after the initial decrease, and maximum tumour growth rate was also twice the control values on Day 13. Accelerated growth rates in irradiated tumours, above those of control tumours, occurred 10-16 days after treatment. The effectiveness of sequential therapy may therefore be improved if given during this period of of accelerated tumour growth. PMID:7437290

  3. Gastrointestinal stromal tumours: an immunohistochemical study of 165 cases.

    PubMed

    Hurlimann, J; Gardiol, D

    1991-10-01

    The phenotype of 165 gastrointestinal stromal tumours was studied by immunohistochemistry. In each case the phenotype was compared to the histological diagnosis. The phenotype was muscle in 49 tumours (30%), neural in 18 (11%), histiocytic in 20 (12%) and mixed in five (3%); 68 tumours (41%) were positive for vimentin only, four tumours had no markers and one tumour was positive for keratin only. Histologically, the tumours were classified as smooth muscle, probably smooth muscle, probably nerve sheath tumours or tumours of undetermined differentiation. In 30 histologically unequivocal muscle tumours, the phenotype was muscle in 28. Half of them, all benign, arose in the oesophagus or gastric cardia. Apart from this group, there was no correlation between phenotype, site of tumour and histological differentiation. Actin was a more sensitive muscle marker than desmin. With the exception of oesophageal tumours, the histological appearances alone could not establish a diagnosis of malignancy and were inadequate in evaluating differentiation. Immunohistochemical examination determined differentiation in 54% of the tumours, but this finding should be interpreted with caution in terms of histogenesis. It allowed us, however, to specify the differential diagnosis in 57 tumours in which the histological diagnosis was uncertain. PMID:1657758

  4. A retrospective study of 21 cases of malignant odontogenic tumours from two tertiary health centres in Nigeria

    PubMed Central

    Lawal, Ahmed Oluwatoyin; Soyele, Olujide Oladele; Akinyamoju, Akindayo Olufunto

    2015-01-01

    Introduction Malignant odontogenic tumours (MOTs) are relatively rare tmours and only few cases have been reported in the sub-Sahara African literature. The aim of this study was to describe the demographic distribution of malignant odontogenic tumours in two tertiary health centres based on the current WHO 2005 classification scheme. Methods We reviewed 21 malignant odontogenic tumours out of a total of 374 odontogenic tumours from two Tertiary Health Centres. Information regarding histology, location, patients age and gender for MOTs were analysed using SPSS for Windows (version 20.0; SPSS Inc. Chicago, IL). Results Twenty one (5.6%) MOTs out of a total of 374 odontogenic tumours were seen from the two institutions over the study period. The median age for MOTs was 42.0 (±19.0) years (range = 16-66 years). The male: female ratio was 2.5:1 and 85.7% occurred in the mandible. Ameloblastic carcinoma (AC) with 13 (61.9%) cases was the most common MOT. AC had a mean age of 37.5 (±11.9) years. AC had a mandible: maxilla ratio of 5.5:1 with majority (84.6%) occurring in the posterior mandible. Conclusion This study showed that MOTs are rare lesions. AC was the most common MOT and majority of MOTs occurred in the posterior mandible of male patients. The study helps to better elucidate the demography of MOTs in sub-Sahara Africans. PMID:26185562

  5. MHC class I antigens and tumour-infiltrating leucocytes in laryngeal cancer: long-term follow-up.

    PubMed Central

    Esteban, F.; Redondo, M.; Delgado, M.; Garrido, F.; Ruiz-Cabello, F.

    1996-01-01

    Alteration in MHC class I expression may be used by cancer cells to avoid immune destruction. Much experimental evidence supports this idea, although survival studies are very scarce. To investigate whether the presence or absence of HLA-A, -B and -C antigens in laryngeal carcinoma influences survival, a series of 60 primary laryngeal tumours treated surgically and normal tissues were evaluated in frozen sections for the expression of MHC class I antigens and tumour-infiltrating leucocytes (CD3, CD4, CD8, CD11b, CD1, CD20 and CD16), using monoclonal antibodies and the APAAP, technique. Long-term follow-up from the patients is available, ranging from 6 to 10 years. Thirteen tumours presented total HLA-ABC loss, five selective losses of HLA-A antigens and one absence of HLA-B antigens. Total losses were statistically associated with several clinical and pathological parameters, but there were no differences regarding tumour-infiltrating leucocytes. After conducting a prospective study, only T and N staging and scoring according to Glanz's malignancy classification were found to be independently related to patients' outcome. From our data, we conclude that neither complete loss of HLA class I antigens nor tumour-infiltrating leucocytes appear to influence survival in squamous cell carcinoma of the larynx. PMID:8956796

  6. Metastatic colonization by circulating tumour cells.

    PubMed

    Massagué, Joan; Obenauf, Anna C

    2016-01-21

    Metastasis is the main cause of death in people with cancer. To colonize distant organs, circulating tumour cells must overcome many obstacles through mechanisms that we are only now starting to understand. These include infiltrating distant tissue, evading immune defences, adapting to supportive niches, surviving as latent tumour-initiating seeds and eventually breaking out to replace the host tissue. They make metastasis a highly inefficient process. However, once metastases have been established, current treatments frequently fail to provide durable responses. An improved understanding of the mechanistic determinants of such colonization is needed to better prevent and treat metastatic cancer. PMID:26791720

  7. A Large Extragnathic Keratocystic Odontogenic Tumour

    PubMed Central

    Bavle, Radhika M.; Muniswamappa, Sudhakara; Narasimhamurthy, Srinath

    2015-01-01

    Odontogenic keratocysts (OKCs) are developmental cysts which occur typically in the jawbones. They present more commonly in the posterior mandible of young adults than the maxilla. OKCs have been reclassified under odontogenic tumours in 2005 by the WHO and have since been termed as keratocystic odontogenic tumours (KCOTs). Here we report a case of a recurrent buccal lesion in a 62-year-old man which was provisionally diagnosed as a space infection (buccal abscess) but surprisingly turned out to be a soft tissue KCOT in an unusual location on histopathologic examination. PMID:26770859

  8. Extracutaneous glomus tumour of the trachea

    PubMed Central

    ?ochowski, Mariusz Piotr; Jesionek-Kupnicka, Dorota; Kozak, Józef

    2015-01-01

    A 38-year-old man presenting expiratory stridor and high-grade dyspnoea was admitted to hospital in Lodz in February 2013. Chest radiographs and computed tomography scans showed a solid lesion in the upper part of the trachea occluding 85% of the airway lumen. A segmental resection of the trachea with a subsequent end-to-end anastomosis was performed. Histopathology showed an extracutaneous glomus tumour. There were no postoperative complications. Tracheal resection is the primary curative method in cases of this rare tumour. PMID:26702289

  9. Sertoli cell tumour in an Amur tiger.

    PubMed

    Scudamore, C L; Meredith, A L

    2001-01-01

    The histological and immunohistochemical characteristics of a malignant Sertoli cell tumour in a 17-year-old Amur tiger (Panthera tigris altaica) are described. Histological examination of the primary lesion in the right testis and metastatic lesions throughout the internal organs showed a variable cellular pattern with an admixture of tubular structures divided by fine stroma filled with fusiform to stellate cells, and sheets of polygonal cells with abundant vacuolated cytoplasm. Immunohistochemical techniques demonstrated strong positive staining for neuron-specific enolase and variable positive staining for vimentin in neoplastic cells, supporting a diagnosis of a tumour of Sertoli cell origin. PMID:11428192

  10. A skull stripping method using deformable surface and tissue classification

    NASA Astrophysics Data System (ADS)

    Tao, Xiaodong; Chang, Ming-Ching

    2010-03-01

    Many neuroimaging applications require an initial step of skull stripping to extract the cerebrum, cerebellum, and brain stem. We approach this problem by combining deformable surface models and a fuzzy tissue classification technique. Our assumption is that contrast exists between brain tissue (gray matter and white matter) and cerebrospinal fluid, which separates the brain from the extra-cranial tissue. We first analyze the intensity of the entire image to find an approximate centroid of the brain and initialize an ellipsoidal surface around it. We then perform a fuzzy tissue classification with bias field correction within the surface. Tissue classification and bias field are extrapolated to the entire image. The surface iteratively deforms under a force field computed from the tissue classification and the surface smoothness. Because of the bias field correction and tissue classification, the proposed algorithm depends less on particular imaging contrast and is robust to inhomogeneous intensity often observed in magnetic resonance images. We tested the algorithm on all T1 weighted images in the OASIS database, which includes skull stripping results using Brain Extraction Tool; the Dice scores have an average of 0.948 with a standard deviation of 0.017, indicating a high degree of agreement. The algorithm takes on average 2 minutes to run on a typical PC and produces a brain mask and membership functions for gray matter, white matter, and cerebrospinal fluid. We also tested the algorithm on T2 images to demonstrate its generality, where the same algorithm without parameter adjustment gives satisfactory results.

  11. [International Society of Urological Pathology (ISUP) Vancouver Classification of Renal Neoplasia 2012].

    PubMed

    Hes, Ond?ej

    2014-01-01

    Kidney tumours form a broad spectrum of distinguished histopathological and molecular genetic entities. The last WHO classification is dated to 2004. Current classification has been published in October 2013 by ISUP (International Society of Urological Pathology). There were 5 new epithelials tumours: tubulocystic renal cell carcinoma (RCC), acquired cystic disease-associated RCC, clear cell (tubulo-)papillary RCC, the MiT family translocation RCCs (in particular t(6;11) RCC), and hereditary leiomyomatosis RCC syndrome-associated RCC. Another 3 subtypes of RCC were added as "provisional" entities: thyroid-like follicular RCC; succinate dehydrogenase B deficiency-associated RCC; and ALK translocation RCC. Modifications were performed in already existing entities: multicystic clear cell RCC (formerly multilocular cystic RCC) is newly included as a subcategory of clear cell RCC with low malignant potential. Oncocytic papillary RCC (PRCC) has not been recognized as a distinctive subcategory of PRCC yet. Hybrid oncocytic-chromophobe tumour was placed within the chromophobe RCC category. Recent advances related to collecting duct carcinoma, renal medullary carcinoma, and mucinous spindle cell and tubular RCC were elucidated. Outside of the epithelial category, current approach to our understanding of angiomyolipoma, including the epithelioid variant and angiomyolipoma with epithelial cysts was clarified. Cystic nephroma and mixed epithelial and stromal tumour were considered as a spectrum of one entity. Synovial sarcoma was placed within the sarcoma group. The new classification is to be referred to as the International Society of Urological Pathology Vancouver Classification of Renal Neoplasia. PMID:25418900

  12. Cutaneous location of atypical teratoid/rhabdoid tumour.

    PubMed

    Bellon, Nathalia; Fraitag, Sylvie; Miquel, Catherine; Salomon, Laurent J; Bourdeaut, Franck; Bodemer, Christine; Roujeau, Thomas; Zerah, Michel; Hadj-Rabia, Smail

    2014-07-01

    Atypical teratoid/rhabdoid tumour is a rare and highly malignant tumour of the posterior fossae nervous system that occurs in children especially in the first few years of life. Cutaneous location is not previously reported. A newborn boy was referred for both aqueductal stenosis detected antenatally and skin tags mimicking hamartoma. The cerebral tumour increased in size during a few months leading to both skin and cerebral biopsies. Integrase Interactor-1 (INI-1) immunostaining and tumoural and leukocytes INI-1 gene sequencing confirmed the atypical teratoid/rhabdoid tumour nature of the cerebral tumour. INI-1 immunostaining in skin biopsy confirmed the dermal location of rhabdoid tumour. Thus, unusual cutaneous lesions may be part of atypical teratoid/rhabdoid tumour. The loss of Integrase INI-1 on immunohistochemical staining is characteristic. PMID:24284868

  13. Systematic pan-cancer analysis of tumour purity

    PubMed Central

    Aran, Dvir; Sirota, Marina; Butte, Atul J.

    2015-01-01

    The tumour microenvironment is the non-cancerous cells present in and around a tumour, including mainly immune cells, but also fibroblasts and cells that comprise supporting blood vessels. These non-cancerous components of the tumour may play an important role in cancer biology. They also have a strong influence on the genomic analysis of tumour samples, and may alter the biological interpretation of results. Here we present a systematic analysis using different measurement modalities of tumour purity in >10,000 samples across 21 cancer types from the Cancer Genome Atlas. Patients are stratified according to clinical features in an attempt to detect clinical differences driven by purity levels. We demonstrate the confounding effect of tumour purity on correlating and clustering tumours with transcriptomics data. Finally, using a differential expression method that accounts for tumour purity, we find an immunotherapy gene signature in several cancer types that is not detected by traditional differential expression analyses. PMID:26634437

  14. Intraoperative intravital microscopy permits the study of human tumour vessels.

    PubMed

    Fisher, Daniel T; Muhitch, Jason B; Kim, Minhyung; Doyen, Kurt C; Bogner, Paul N; Evans, Sharon S; Skitzki, Joseph J

    2016-01-01

    Tumour vessels have been studied extensively as they are critical sites for drug delivery, anti-angiogenic therapies and immunotherapy. As a preclinical tool, intravital microscopy (IVM) allows for in vivo real-time direct observation of vessels at the cellular level. However, to date there are no reports of intravital high-resolution imaging of human tumours in the clinical setting. Here we report the feasibility of IVM examinations of human malignant disease with an emphasis on tumour vasculature as the major site of tumour-host interactions. Consistent with preclinical observations, we show that patient tumour vessels are disorganized, tortuous and ∼50% do not support blood flow. Human tumour vessel diameters are larger than predicted from immunohistochemistry or preclinical IVM, and thereby have lower wall shear stress, which influences delivery of drugs and cellular immunotherapies. Thus, real-time clinical imaging of living human tumours is feasible and allows for detection of characteristics within the tumour microenvironment. PMID:26883450

  15. Systematic pan-cancer analysis of tumour purity.

    PubMed

    Aran, Dvir; Sirota, Marina; Butte, Atul J

    2015-01-01

    The tumour microenvironment is the non-cancerous cells present in and around a tumour, including mainly immune cells, but also fibroblasts and cells that comprise supporting blood vessels. These non-cancerous components of the tumour may play an important role in cancer biology. They also have a strong influence on the genomic analysis of tumour samples, and may alter the biological interpretation of results. Here we present a systematic analysis using different measurement modalities of tumour purity in >10,000 samples across 21 cancer types from the Cancer Genome Atlas. Patients are stratified according to clinical features in an attempt to detect clinical differences driven by purity levels. We demonstrate the confounding effect of tumour purity on correlating and clustering tumours with transcriptomics data. Finally, using a differential expression method that accounts for tumour purity, we find an immunotherapy gene signature in several cancer types that is not detected by traditional differential expression analyses. PMID:26634437

  16. Intraoperative intravital microscopy permits the study of human tumour vessels

    PubMed Central

    Fisher, Daniel T.; Muhitch, Jason B.; Kim, Minhyung; Doyen, Kurt C.; Bogner, Paul N.; Evans, Sharon S.; Skitzki, Joseph J.

    2016-01-01

    Tumour vessels have been studied extensively as they are critical sites for drug delivery, anti-angiogenic therapies and immunotherapy. As a preclinical tool, intravital microscopy (IVM) allows for in vivo real-time direct observation of vessels at the cellular level. However, to date there are no reports of intravital high-resolution imaging of human tumours in the clinical setting. Here we report the feasibility of IVM examinations of human malignant disease with an emphasis on tumour vasculature as the major site of tumour-host interactions. Consistent with preclinical observations, we show that patient tumour vessels are disorganized, tortuous and ∼50% do not support blood flow. Human tumour vessel diameters are larger than predicted from immunohistochemistry or preclinical IVM, and thereby have lower wall shear stress, which influences delivery of drugs and cellular immunotherapies. Thus, real-time clinical imaging of living human tumours is feasible and allows for detection of characteristics within the tumour microenvironment. PMID:26883450

  17. Giant resectable mediastinal carcinoid tumour--thymic origin or not?

    PubMed

    Cakir, E; Aydin, L Yilmaz; Gulgosteren, M

    2009-01-01

    Carcinoid tumours of the mediastinum are rare. We report a case of a giant mediastinal tumour in a 76-year-old man who had long-standing respiratory symptoms. The pathologic diagnosis was typical carcinoid tumour. Because of the enormous size of the tumour it was difficult to determine the site of origin. The patient has no sign of recurrence or metastasis 6 months after the operation. PMID:19803278

  18. [Tumorogenesis and skin tumours in the elderly].

    PubMed

    Wild, T; Altenburg, A; Karagiannidis, I; Mauch, C; Zouboulis, C C

    2016-02-01

    More than 1.5 million people were diagnosed with skin cancer in 2012 in Germany-of which 318,000 were malignant melanoma. The number of malignant skin tumours has increased by 60 % since 2005. Epithelial skin cancers are even more common. Since 2012, 1.3 million diagnoses have been documented. This incidence represents an increase of 79 % within 7 years. The number of skin cancer patients treated in German hospitals has also increased. In 2014, 99,613 patients were treated as inpatients with the diagnosis of skin cancer; in 2000 there were 57,147 patients. This was the largest growth rate among all cancer treatments in hospitalised patients. The continuously changing age pyramid leads to an expected further growth of the incidence of skin tumours. In parallel the development of molecular knowledge in tumorigenesis is also rapid. A series of cell-specific mutations have been described in recent years for various skin tumours. Mutations are found mainly in genes engaging their translation products at key positions in regulatory cell metabolism or cell division. These include oncogenes, which have greatly increased activity due to targeted mutations or tumor suppressor genes and act under physiological conditions as negative regulators that are inactivated by mutations. These findings have led to the development of a series of new promising compounds for the treatment of skin tumours. PMID:26787292

  19. Carpal tunnel syndrome secondary to Masson's tumour.

    PubMed

    Titchener, Andrew Gordon; Arenas-Prat, Joan

    2015-12-01

    We present a case of a Masson's tumour causing carpal tunnel syndrome. Space occupying lesions should be considered as a differential in refractory cases of carpal tunnel syndrome, especially those in whom the symptoms are dynamic. Once radiological investigation confirms such a diagnosis, we advocate surgical excision, as malignancy can only be excluded via histological examination. PMID:26566345

  20. Karyotypic abnormalities in tumours of the pancreas.

    PubMed Central

    Bardi, G.; Johansson, B.; Pandis, N.; Mandahl, N.; Bak-Jensen, E.; Andrén-Sandberg, A.; Mitelman, F.; Heim, S.

    1993-01-01

    Short-term cultures from 20 pancreatic tumours, three endocrine and 17 exocrine, were cytogenetically analysed. All three endocrine tumours had a normal chromosome complement. Clonal chromosome aberrations were detected in 13 of the 17 exocrine tumours: simple karyotypic changes were found in five carcinomas and numerous numerical and/or structural changes in eight. When the present findings and those previously reported by our group were viewed in conjunction, the most common numerical imbalances among the 22 karyotypically abnormal pancreatic carcinomas thus available for evaluation turned out to be, in order of falling frequency, -18, -Y, +20, +7, +11 and -12. Imbalances brought about by structural changes most frequently affected chromosomes 1 (losses in 1p but especially gains of 1q), 8 (in particular 8q gains but also 8p losses), and 17 (mostly 17q gain but also loss of 17p). Chromosomal bands 1p32, 1q10, 6q21, 7p22, 8p21, 8q11, 14p11, 15q10-11, and 17q11 were the most common breakpoint sites affected by the structural rearrangements. Abnormal karyotypes were detected more frequently in poorly differentiated and anaplastic carcinomas than in moderately and well differentiated tumours. Images Figure 1 PMID:8494707

  1. Canine oral mucosal mast cell tumours.

    PubMed

    Elliott, J W; Cripps, P; Blackwood, L; Berlato, D; Murphy, S; Grant, I A

    2016-03-01

    Mast cell tumours (MCTs) are the most common cutaneous tumours of dogs, however rarely they can arise from the oral mucosa. This subset of MCT is reported to demonstrate a more aggressive clinical course than those tumours on the haired skin and the authors hypothesised that dogs with oral, mucosal MCT would have a high incidence of local lymph node metastasis at presentation and that this would be a negative prognostic factor. An additional hypothesis was that mitotic index (MI) would be prognostic. This retrospective study examines 33 dogs with MCTs arising from the oral mucosa. The results suggest that oral mucosal MCTs in the dog have a high incidence of lymph node metastasis at diagnosis (55%) which results in a poor prognosis. MI and nodal metastasis is highly prognostic. Loco-regional progression is common in these patients and dogs with adequate local control of their tumour had an improved outcome. Despite a more aggressive clinical course, treatment can result in protracted survivals, even when metastasis is present. PMID:24215587

  2. Malignant gonadal tumour formation in intersexual states

    PubMed Central

    Pigott, H. W. S.

    1975-01-01

    Two cases of malignant tumour are reported in phenotypically male hermaphrodites. The importance of establishing the presence of persistent Müllerian duct structures in pseudo-hermaphrodites is discussed in relation to prophylactic castration in anticipation of malignant change. ImagesFig. 1Fig. 2 PMID:1197157

  3. Mycobacterial spindle cell pseudotumour of the brain in a patient with sarcoidosis.

    PubMed

    Ismail, Iyad; Carey, Martyn; Trotter, Simon; Kunst, Heinke

    2015-01-01

    Mycobacterial spindle cell pseudotumours (MSP) are benign lesions characterised by local proliferation of spindle-shaped histiocytes caused by mycobacterial infections. Cerebral MSP due to Mycobacterium avium intracellulare (MAI) infection is rare, and is often misdiagnosed clinically and radiologically as a brain tumour. We present a case with underlying sarcoidosis and known pulmonary MAI infection presenting with partial seizures and headaches. Imaging of the brain revealed a solitary extra axial tumour within the right temporal area. Biopsy of the tumour showed evidence of MPS due to MAI infection. Prolonged treatment with antituberculous therapy showed complete resolution of the cerebral lesion. PMID:26153278

  4. The mechanical microenvironment in cancer: How physics affects tumours.

    PubMed

    Nagelkerke, Anika; Bussink, Johan; Rowan, Alan E; Span, Paul N

    2015-12-01

    The tumour microenvironment contributes greatly to the response of tumour cells. It consists of chemical gradients, for example of oxygen and nutrients. However, a physical environment is also present. Apart from chemical input, cells also receive physical signals. Tumours display unique mechanical properties: they are a lot stiffer than normal tissue. This may be either a cause or a consequence of cancer, but literature suggests it has a major impact on tumour cells as will be described in this review. The mechanical microenvironment may cause malignant transformation, possibly through activation of oncogenic pathways and inhibition of tumour suppressor genes. In addition, the mechanical microenvironment may promote tumour progression by influencing processes such as epithelial-to-mesenchymal transition, enhancing cell survival through autophagy, but also affects sensitivity of tumour cells to therapeutics. Furthermore, multiple intracellular signalling pathways prove sensitive to the mechanical properties of the microenvironment. It appears the increased stiffness is unlikely to be caused by increased stiffness of the tumour cells themselves. However, there are indications that tumours display a higher cell density, making them more rigid. In addition, increased matrix deposition in the tumour, as well as increased interstitial fluid pressure may account for the increased stiffness of tumours. Overall, tumour mechanics are significantly different from normal tissue. Therefore, this feature should be further explored for use in cancer prevention, detection and treatment. PMID:26343578

  5. The roles of TGF? in the tumour microenvironment

    PubMed Central

    Pickup, Michael; Novitskiy, Sergey; Moses, Harold L.

    2014-01-01

    The influence of the microenvironment on tumour progression is becoming clearer. In this Review we address the role of an essential signalling pathway, that of transforming growth factor-?, in the regulation of components of the tumour microenvironment and how this contributes to tumour progression. PMID:24132110

  6. Management of tumour spillage during parotid surgery for pleomorphic adenoma.

    PubMed

    Kerawala, Cyrus; Brennan, Peter A; Cascarini, Luke; Godden, Darryl; Coombes, Darryl; McCaul, Jim

    2014-01-01

    Over the decades parotid surgery for benign tumours has developed into a reproducible, conservative operation with low morbidity. Despite the advances tumour spillage can still occur, and its management remains controversial. Since no universal consensus exists the aim of this article is to review the approach to tumour spillage and derive a protocol for its management based on existing evidence. PMID:23810456

  7. Glutathione S-transferase activity and isoenzyme composition in benign ovarian tumours, untreated malignant ovarian tumours, and malignant ovarian tumours after platinum/cyclophosphamide chemotherapy.

    PubMed Central

    van der Zee, A. G.; van Ommen, B.; Meijer, C.; Hollema, H.; van Bladeren, P. J.; de Vries, E. G.

    1992-01-01

    Glutathione S-transferase (GST) isoenzyme composition, isoenzyme quantities and enzymatic activity were investigated in benign (n = 4) ovarian tumours and malignant ovarian tumours, before (n = 20) and after (n = 16) chemotherapy. Enzymatic activity of GST in cytosols was measured by determining 1-chloro-2,4-dinitrobenzene conjugation with glutathione, cytosolic GST subunits were determined by wide pore reversed phase HPLC, using a S-hexylglutathione-agarose affinity column, and isoelectric focussing. Both GST activity and GST pi amount were not related to histopathologic type, differentiation grade, or tumour volume index in untreated malignant tumours. GST isoenzyme patterns were identical in benign tumours and malignant tumours before and after platinum/cyclophosphamide chemotherapy, while GST pi was the predominant transferase. Mean GST activity and GST pi amount were decreased (P < 0.05) in malignant ovarian tumours after platinum/cyclophosphamide chemotherapy compared to untreated ovarian malignant tumours. No relation was found in untreated ovarian tumours between GST pi amount and response to platinum/cyclophosphamide chemotherapy. Thus, within the limitations of the current study no arguments were found for a role of GST in in vivo drug resistance of malignant ovarian tumours to platinum/cyclophosphamide chemotherapy. PMID:1419639

  8. Orbital tumours and tumour-like lesions: exploring the armamentarium of multiparametric imaging.

    PubMed

    Purohit, Bela S; Vargas, Maria Isabel; Ailianou, Angeliki; Merlini, Laura; Poletti, Pierre-Alexandre; Platon, Alexandra; Delattre, Bénédicte M; Rager, Olivier; Burkhardt, Karim; Becker, Minerva

    2016-02-01

    Although the orbit is a small anatomical space, the wide range of structures present within it are often the site of origin of various tumours and tumour-like conditions, both in adults and children. Cross-sectional imaging is mandatory for the detection, characterization, and mapping of these lesions. This review focuses on multiparametric imaging of orbital tumours. Each tumour is reviewed in relation to its clinical presentation, compartmental location, imaging characteristics, and its histological features. We herein describe orbital tumours as lesions of the globe (retinoblastoma, uveal melanoma), optic nerve sheath complex (meningioma, optic nerve glioma), conal-intraconal compartment (hemangioma), extraconal compartment (dermoid/epidermoid, lacrimal gland tumours, lymphoma, rhabdomysarcoma), and bone and sinus compartment (fibrous dysplasia). Lesions without any typical compartmental localization and those with multi-compartment involvement (veno-lymphatic malformation, plexiform neurofibroma, idiopathic orbital pseudotumour, IgG4 related disease, metastases) are also reviewed. We discuss the role of advanced imaging techniques, such as MR diffusion-weighted imaging (DWI), diffusion tensor imaging, fluoro-2-deoxy-D-glucose positron emission tomography CT (FDG-PET CT), and positron emission tomography MRI (MRI PET) as problem-solving tools in the evaluation of those orbital masses that present with non-specific morphologic imaging findings. Main messages/Teaching points • A compartment-based approach is essential for the diagnosis of orbital tumours. • CT and MRI play a key role in the work-up of orbital tumours. • DWI, PET CT, and MRI PET are complementary tools to solve diagnostic dilemmas. • Awareness of salient imaging pearls and diagnostic pitfalls avoids interpretation errors. PMID:26518678

  9. Tumour cell-derived Wnt7a recruits and activates fibroblasts to promote tumour aggressiveness.

    PubMed

    Avgustinova, Alexandra; Iravani, Marjan; Robertson, David; Fearns, Antony; Gao, Qiong; Klingbeil, Pamela; Hanby, Andrew M; Speirs, Valerie; Sahai, Erik; Calvo, Fernando; Isacke, Clare M

    2016-01-01

    Stromal fibroblast recruitment to tumours and activation to a cancer-associated fibroblast (CAF) phenotype has been implicated in promoting primary tumour growth and progression to metastatic disease. However, the mechanisms underlying the tumour:fibroblast crosstalk that drive the intertumoural stromal heterogeneity remain poorly understood. Using in vivo models we identify Wnt7a as a key factor secreted exclusively by aggressive breast tumour cells, which induces CAF conversion. Functionally, this results in extracellular matrix remodelling to create a permissive environment for tumour cell invasion and promotion of distant metastasis. Mechanistically, Wnt7a-mediated fibroblast activation is not dependent on classical Wnt signalling. Instead, we demonstrate that Wnt7a potentiates TGF? receptor signalling both in 3D in vitro and in vivo models, thus highlighting the interaction between two of the key signalling pathways in development and disease. Importantly, in clinical breast cancer cohorts, tumour cell Wnt7a expression correlates with a desmoplastic, poor-prognosis stroma and poor patient outcome. PMID:26777421

  10. Tumour cell-derived Wnt7a recruits and activates fibroblasts to promote tumour aggressiveness

    PubMed Central

    Avgustinova, Alexandra; Iravani, Marjan; Robertson, David; Fearns, Antony; Gao, Qiong; Klingbeil, Pamela; Hanby, Andrew M.; Speirs, Valerie; Sahai, Erik; Calvo, Fernando; Isacke, Clare M.

    2016-01-01

    Stromal fibroblast recruitment to tumours and activation to a cancer-associated fibroblast (CAF) phenotype has been implicated in promoting primary tumour growth and progression to metastatic disease. However, the mechanisms underlying the tumour:fibroblast crosstalk that drive the intertumoural stromal heterogeneity remain poorly understood. Using in vivo models we identify Wnt7a as a key factor secreted exclusively by aggressive breast tumour cells, which induces CAF conversion. Functionally, this results in extracellular matrix remodelling to create a permissive environment for tumour cell invasion and promotion of distant metastasis. Mechanistically, Wnt7a-mediated fibroblast activation is not dependent on classical Wnt signalling. Instead, we demonstrate that Wnt7a potentiates TGFβ receptor signalling both in 3D in vitro and in vivo models, thus highlighting the interaction between two of the key signalling pathways in development and disease. Importantly, in clinical breast cancer cohorts, tumour cell Wnt7a expression correlates with a desmoplastic, poor-prognosis stroma and poor patient outcome. PMID:26777421

  11. A chemically modified antibody mediates complete eradication of tumours by selective disruption of tumour blood vessels

    PubMed Central

    Palumbo, A; Hauler, F; Dziunycz, P; Schwager, K; Soltermann, A; Pretto, F; Alonso, C; Hofbauer, G F; Boyle, R W; Neri, D

    2011-01-01

    Background: The possibility of eradicating cancer by selective destruction of tumour blood vessels may represent an attractive therapeutic avenue, but most pharmaceutical agents investigated so far did not achieve complete cures and are not completely specific. Antibody conjugates now allow us to evaluate the impact of selective vascular shutdown on tumour viability and to study mechanisms of action. Methods: We synthesised a novel porphyrin-based photosensitiser suitable for conjugation to antibodies and assessed anticancer properties of its conjugate with L19, a clinical-stage human monoclonal antibody specific to the alternatively spliced EDB domain of fibronectin, a marker of tumour angiogenesis. Results: Here we show in two mouse model of cancer (F9 and A431) that L19 is capable of highly selective in vivo localisation around tumour blood vessels and that its conjugate with a photosensitiser allows selective disruption of tumour vasculature upon irradiation, leading to complete and long-lasting cancer eradication. Furthermore, depletion experiments revealed that natural killer cells are essential for the induction of long-lasting complete responses. Conclusions: These results reinforce t