National Repository of Grey Literature 5 records found  Search took 0.01 seconds. 
Rare tumors of gastrointenstinal tract
Dubová, Magdaléna ; Daum, Ondřej (advisor) ; Šíma, Radek (referee) ; Jirásek, Tomáš (referee)
Tumors of digestive tract are among the most common neoplasms worldwide. Morphologically and clinically, they represent a heterogenous group of lesions, in which the tumors of epithelial origin occupy a leading position. Due to their rarity, tumors of non- epithelial, mainly mesenchymal origin remain hidden in the shade cast by the huge category of epithelial tumors. Thanks to the current diagnostic opportunities, the pathogenesis and molecular genetics of many of these lesions have been revealed. New data has influenced not only the differential diagnosis algorithms, but also has contributed to the development of targeted therapy, which leads to prolongation of survival and improvement of quality of life of affected patients. The aim of the study was to elucidate the molecular genetic background and associated differential diagnostic signs of selected mesenchymal tumors of the digestive tract. Material for the study was retrieved from the archives of Šikl's Department of Pathology of Medical Faculty of Charles University in Pilsen and the Tumor Registry of the Head of Šikl's Department of Pathology, Professor Michal Michal, M.D.. The doctoral thesis is divided into two parts. The first part introduces the issue of rare tumors of the gastrointestinal system, with particular attention to the...
Clinicopathological aspects and differential diagnostics of Lynch syndrome
Dušek, Martin ; Daum, Ondřej (advisor) ; Zámečník, Josef (referee) ; Šíma, Radek (referee)
Lynch syndrome (LS), formerly known as hereditary nonpolyposis colorectal cancer (HNPCC) is a familial cancer syndrome with an autosomal dominant inheritance pattern. Its genetic basis is most commonly a germline mutation in one of the mismatch repair (MMR) genes, that are responsible for correction of errors ocurring during DNA replication. Dysfunction of this repairing system leads to the formation and progression of tumors, especially colorectal cancer (CRC). According to the literature LS represents 3-5 % of all CRC. Additional extracolonic tumors associated with LS include endometrium, ovary, stomach, small bowel, pancreas, hepatobiliary tract, upper uroepithelial tract, brain and cutaneous sebaceous tumors. Early age of onset is a typical feature of LS-associated tumors, in comparison with general population. Malignancy is often the first manifestation, therefore the LS diagnosis is important not only for the individual patient and his next management, but also for his family members. An exception is represented by the formation of cutaneous sebaceous tumors prior to internal malignancy in one of LS phenotypic variant, called Muir-Torre syndrome. Properly selected screening methods can prevent the formation of malignant tumors by early detection of their premalignant lesions, or at least early...
The study of signaling pathways that modulate multidrug resistance
Dvořák, Pavel ; Souček, Pavel (advisor) ; Daum, Ondřej (referee) ; Benson, Veronika (referee)
The study of signaling pathways that modulate multidrug resistance The theme of cancer cell resistance to anti-cancer drugs including the common mechanisms of resistance development and the theory of cancer stem cells was introduced in the Introduction to the doctoral thesis. The theoretical part was focused more deeply on the two topics - the role of ATP-binding cassette (ABC) transport proteins and chromosomal abnormalities in the development of cancer chemoresistance. The possible therapeutic potential for the treatment of cancer was stressed for both topics. The Results were composed of the commentaries on the five published works, which the author of the thesis conducted as the main author. The first work brought the evidence supporting the hypothesis of the existence of ABC gene expression profiles (signatures), which are common to multiple types of tumors and are associated with significant clinical consequences. These general ABC gene expression profiles could possibly form a new hallmark of cancer. The second work studied more closely a group of acute myeloid leukemia patients, who did not achieve complete cytogenetic remission after two attempts to maintain remission of the malignant disease. The new entity, consisting of patients with the translocation t(2;11)(p21;q23) without the...
Molecular biological detection of viral and bacterial pathogens and their relationship
Kašpírková, Jana ; Hes, Ondřej (advisor) ; Daum, Ondřej (referee) ; Boudová, Ludmila (referee) ; Putzová, Martina (referee)
1 We report a case of an eccrine syringofibroadenoma (ESFA) associated with well- differentiated squamous cell carcinoma. The patient was an 85-year-old man, who had a 2.5x2.5-cm, brown-colored ulcerated nodule, with a fragile, flesh-colored bleeding surface located beyond the metacarpophalangeal joint of the second finger of his left hand. Histopathologically, there were areas of a well-differentiated squamous cell carcinoma, alternating with the typical area of ESFA characterized by anastomosing cords, strands, and columns of epithelial cells extending from the crusted epidermis into a thickened, edematous, myxoid vascular-rich dermis. Immunohistochemically, the areas with dysplastic epithelium were positive for p16, whereas the benign ESFA parts tested negative. Human papillomavirus was detected in the lesional tissue by polymerase chain reaction, and the subsequent sequencing analysis demonstrated that the virus was close to human papillomavirus type 107. 2 The authors report a case of basaloid carcinoma involving the anus and rectum of a 57-year- old woman. Microscopically, the tumor showed unusual morphologic features strongly resembling a spiradenocylindroma because it consisted, in most parts, of basaloid cell nodules arranged in a jigsaw-puzzle fashion containing or surrounded by eosinophilic basal...
Diagnostic morphological features of PDGFRA-mutated gastrointestinal
Daum, Ondřej ; Hes, Ondřej (advisor) ; Mandys, Václav (referee) ; Ehrmann, Jiří (referee) ; Zámečník, Josef (referee)
Daum O., Grossmann P., Vanecek T., Sima R., Mukensnabl P., Michal M. (2006): Diagnostic morphological features of PDGFRA-mutated gastrointestinal stromal tumors: Molecular genetic and histological analysis of 60 cases of gastric GISTs. Ann. Diagn. Pathol. In Press Summary In this study, 60 gastrointestinal stromal tumors (GISTs) of the stomach were analyzed to elucidate the possible relation of their morphology to mutation status of KIT and PDGFRA genes. The patients included 27 men and 33 women with a mean age of 63,8 years (range 12 to 92). Only one tumor occurred before the age of 21 years. KIT mutations were detected in 31 cases (51,7%), PDGFRA mutations in 22 cases (36,7%), and seven cases (11,7%) were KIT and PDGFRA wild type. When the mutation status was correlated with histological features of the tumors, epithelioid or mixed epithelioid/spindle cell pattern and mast cell infiltration were found as the most reliable signs of PDGFRA mutation. Neoplastic rhabdoid cells and multinucleated giant cells, also previously reported as features of PDGFRA mutated GISTs, seemed to be less specific but still helpful markers in our study. Finally, tumor infiltrating lymphocytes and myxoid stroma do not seem to be valuable histological signs. Daum O., Klecka J., Ferda J., Treska V., Vanecek T., Sima R., Mukensnabl...

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