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A Roessner

Publications and source records attributed to A Roessner.

At least 217 records · Page 12Linked to original sources
PubMed1987

[Space-occupying tumor lesions of the spinal column. An analysis of the material submitted to the Westphalia Bone Tumor Register].

308 tumorous lesions of the spine were identified in the material submitted to the bone tumour register in Münster for recording. Histological examination revealed metastases in 38.6% primary bone tumours in 33.1%, tumour-like lesions in 10% and haematological and lymphatic disease in 13%. 5.3% of all lesions could not be classified in these groups. Primary bone tumours were seen more often than metastases in the cervical spine, the sacrum and the coccyx. 54.9% of the primary bone tumours of the spine were benign. However, only 31.2% of all the tumorous lesions of the spine, metastases included, were benign. The portion of malignant disorders increased with increasing age. The risk of having a malignant spine tumour was 5.9% in patients under 10 years of age but 92.3% in patients in the seventh decade.

Age Factors↗
PubMed1987

[Primary bone tumors and tumor-like lesions of the spine. The accuracy of radiological assessment criteria].

In 79 primary bone tumors and tumorlike lesions of the spine radiological criteria are analyzed, which allow to assess the biological nature. Criteria associated with benign lesions, are: regular, trabecular matrix, osteoplastic matrix, exostotic growth, location in the posterior elements, absent soft tissue mass, and bulging of the vertebra. Criteria suggestive of malignancy are: Soft tissue mass, location inside the vertebral body, no alteration of the vertebral shape, compression fracture, and osteolysis. Benign lesions can be diagnosed with a higher degree of reliability than malignant tumors. Diagnostic accuracy increases in lesions exhibiting more than one criterion of the same group.

Chondroma↗
PubMed1987

Immunocytochemical analysis of Ewing's tumors. Patterns of expression of intermediate filaments and desmosomal proteins indicate cell type heterogeneity and pluripotential differentiation.

Examples of classical Ewing's tumors ("Ewing's sarcomas") of both skeletal and extraskeletal locations were analyzed for the expression of intermediate filament (IF) and cell junction proteins, with the use of immunofluorescence and immunoelectron microscopy as well as gel electrophoresis. In all 11 tumors examined vimentin filaments were abundant. A type of plaque-bearing small cell junction, which is common in these tumors but difficult to classify by morphologic criteria, was identified by antibodies to desmoplakins as true desmosomes. These were found in all cases, although in a very variable proportion of cells. Some of these junctions were associated with vimentin IFs. In addition, 9 of the cases examined showed scattered or clustered cells expressing the simple-epithelium type cytokeratins 8 and 18. Moreover, 3 cases displayed dispersed or clustered cells producing neurofilaments. The value of these observations, notably the cell type heterogeneity, for the diagnosis of tumors of this group is discussed. The results further indicate that Ewing's tumors are derived from a primitive, pluripotential cell that may differentiate, in variable proportions, into cells with mesenchymal, epithelial, and, more rarely, even neural features, suggesting that this tumor should be regarded as a blastoma, rather than as a true sarcoma.

Adolescent↗
PubMed1987

Biologic characterization of human bone tumors. VI. The aneurysmal bone cyst: an enzyme histochemical, electron microscopical, and immunohistological study.

The etiology of aneurysmal bone cyst is still unknown. Most theories of the histogenesis of this lesion assume a vascular origin and speculation has focused on the characteristic pseudoendothelial lining of the cyst walls. In the present study, this structure has been subjected to enzyme histochemical, electron microscopical, and immunohistochemical investigation. Of the enzymes tested only alkaline phosphatase was present in the cyst lining. Electron microscopy revealed fibroblast-like cells covering the walls of cystic cavities, but no genuine endothelium, basement membranes or pericytes were identified. For the immunohistochemical studies a panel of poly- and monoclonal antibodies against HLA-DR antigens, mature and immature macrophages/histiocytes, smooth muscle fibers and endothelial cells, as well as the lectin Ulex europaeus I agglutinin were used. None of these markers demonstrated the presupposed vascular characteristics in the cells constituting the pseudoendothelial lining of the cyst walls. Despite current theories to the contrary, it was concluded that aneurysmal bone cyst is unlikely to originate from the vascular system, and that a new concept of its pathogenesis must be sought.

Acid Phosphatase↗
PubMed1987

What's new in the pathology of atherosclerosis?

Intimal smooth muscle cell proliferation has been known to be the key event in the development of advanced lesions of atherosclerosis. Since the important role of macrophages in the lipoprotein metabolism has been detected, however, current interest focuses on the macrophage reaction in the arterial wall. Animal experiments have shown that blood monocytes become attached to certain endothelial areas and enter the intima, where they are transformed to macrophages. Subendothelial infiltration of monocytes is the earliest cellular event in the formation of fatty streaks. Transformed to macrophages, they incorporate LDL by receptor-mediated endocytosis and are thus transformed to foam cells. The majority of foam cells in the atherosclerotic plaque is derived from macrophages. Furthermore, the importance of macrophages in the regulation of the lipoprotein metabolism and cholesterol homeostasis is increasingly attributed to their secretory capacities. It has been shown in vitro that they can secrete apolipoprotein E which associates with cholesterol and HDL to form a lipoprotein complex, which targets resecreted cholesterol to the liver cells. Recently, apolipoprotein E secretion of macrophages has also been demonstrated immunohistologically in the human atherosclerotic plaque. Cell culture investigations revealed that macrophages secrete different growth factors for fibroblasts and smooth muscle cells. So they are probably able, among other factors, to initiate smooth muscle cell proliferation in the intima. While smooth muscle cell proliferation and matrix components in the arterial wall had occupied the center of interest in previous investigations, the current focus on the cellular reactions of endothelial cells and monocytes/macrophages, especially in the early stages of atherosclerotic plaque formation, seems well justified.

Animals↗
PubMed1987

[Pathology of spinal tumors].

The Bone Tumor Registry of Westphalia contains data on 7,400 tumors and tumor-like lesions of bone, 135 primary spinal tumors, 187 metastases, 98 plasmacytomas, 4 extranodal manifestations of Hodgkin and non-Hodgkin lymphomas of the vertebral column. The most frequent type of primary tumor is the chordoma (35 cases), followed by osteoblastoma (16 cases), eosinophil granuloma (16), and hemangioma (12 cases). Most of the metastases derive from carcinoma of the breast, bronchial carcinoma, or prostate carcinoma. The present review concentrates on differential diagnosis by means of histological examination, with particular reference to immunohistological methods. In addition, the necessity for complementary assessment of the X-ray findings and histology is emphasized. In particular, the current status of knowledge on the prognosis of primary spinal tumors is presented. In our experience, the preparation of nondecalcified plastic sections has proved especially valuable for diagnostic procedures using punch biopsy specimens.

Humans↗
PubMed1987

[Present status of thymoma therapy].

Eight patients with histologically verified thymoma were treated between 1962 and 1985 at the Radiologic Hospital of the University of Münster. All patients were submitted to thoracotomy and subsequent irradiation. A primary irradiation was performed in four cases. The average survival time of the only irradiated patients was 8.5 months. A considerably better average survival time, i.e. 46 months, was reached by surgical procedure with postoperative irradiation. The therapy of choice in the treatment of malignant thymomas is radical operation and subsequent radiotherapy; in case of benign thymomas a postirradiation is not necessary. 25% of our patients showed early recurrences, parathymic syndromes, and hematogenous metastases. Lymphogenic metastases were not observed. Chemotherapy exerted no demonstrable influence on the tumors.

Adult↗
PubMed1986

Improved grading of bone tumors with the monoclonal antibody Ki-67.

A total of 60 bone tumors and tumor-like lesions presenting various grades of malignancy were investigated immunohistologically with the monoclonal antibody Ki-67 directed against a cell proliferation-associated nuclear antigen. The results obtained agree well with those of flow cytometric and autoradiographic studies on similar tumor entities. The monoclonal antibody Ki-67 was found to be a handy and reliable tool for improved grading of bone tumors.

Antibodies, Monoclonal↗
PubMed1986

Biological characterization of human bone tumors. VIII. Expression of HLA-DR antigens in bone tumors and tumor-like lesions.

A total of 45 cases of bone tumors and tumor-like lesions were studied in order to determine the expression of an HLA-DR antigen by the monoclonal antibody 910-D-7, and its possible correlation with histology, using the indirect immunoperoxidase method on frozen sections. The pattern of antigen expression was nearly constant for the individual cell types, though varying in intensity, and did not depend on the biological behavior of the respective lesions. No clear correlation could be established between antigen expression and cell maturation. Although the biological significance of antigen expression in these tumors is not yet understood, it is clear that here, too, the mere presence of an HLA-DR antigen cannot be interpreted as a sign of malignant transformation.

Bone Cysts↗
PubMed1986

Isolation and characterization of proteoglycans and glycosaminoglycans from human chondrosarcoma.

The proteoglycans and glycosaminoglycans of four human chondrosarcomas with different degrees of malignancy (I-III) have been studied. The hydrodynamic size of proteoglycan subunits and the tissue concentration of total glycosaminoglycans decreased with increasing grade of malignancy. The glycosaminoglycan distribution pattern of all chondrosarcomas showed a similar ratio of chondroitin-4-sulfate:chondroitin-6-sulfate but an increasing portion of keratan sulfate from grade I (6.5%) to grade III (19.2%). Determinations of the molecular weight (Mr values) of glycosaminoglycans were made after 3H labeling by alkaline reduction of proteoglycans in the presence of NaB3H4. The Mr of [3H]chondroitin sulfate isomers decreased markedly from grade I (35,500) to grade III (15,100) while the chain length of [3H]keratan sulfate showed minor variations (Mr 5600-6200). The previously reported decrease in the molecular weight of keratan sulfate with increasing degree of malignancy (S. Pal, W. Strider, R. Margolis, G. Gallo, S. Lee-Huang, and L. Rosenberg, 1978, J. Biol. Chem. 253, 1279-1289) was not observed.

Chondrosarcoma↗
PubMed1986

[X-ray morphology and pathologic anatomy of osteoblastoma].

Between 1974 and 1984, 24 patients with osteoblastomas were entered in the bone tumour registry of the Gerhard Domagk Institute of Pathology and Institute for Clinical Radiology of Westphalia. These cases are evaluated. Osteoblastoma is a benign primary bone tumour with a peak incidence between ten and 20 years and a sex ratio of 18 males to 4 females in our series. The site of predilection is the spine (59%) with long bones in second place (32%). The tumor is mostly situated in the medulla. Radiologically it usually appears as a well demarcated translucency with a narrow rim and marginal sclerosis. Variations in radiological appearance and the histology and treatment are described. A malignant variant, the "aggressive osteoblastoma", is discussed and one case is described. The classification of these cases is considered.

Adolescent↗
PubMed1985

Biological characterization of human bone tumors. VII. Detection of malignancy in a giant cell tumor of bone by flow cytometric DNA-analysis.

The biological behavior of giant cell tumors of bone often cannot be definitively evaluated by light and electron microscopical criteria. As DNA aneuploidy was found to be a highly sensitive marker of malignant cells, we have analyzed this descriptive parameter in 4 giant cell tumors of bone by flow cytometry. Three of the four cases were non-metastasizing giant cell tumors, the fourth was a clinically malignant neoplasm presenting extensive visceral metastases four years after first diagnosis. Neither light- nor electron microscopical findings provided unequivocal criteria for defining the biological dignity of the four tumors. DNA aneuploidies were identified in the metastasizing case only, whereas the three clinically benign tumors showed a unimodal euploid DNA distribution. Thus flow cytometric DNA analysis is an additional diagnostic tool for the detection of malignancy in giant cell tumors of bone.

Adult↗