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Biomedical subjects

D Katenkamp

Publications and source records attributed to D Katenkamp.

At least 127 records · Page 7Linked to original sources
PubMed1987

Soft tissue tumors of the head and neck.

From the tumor register of the Institute of Pathology of Jena all soft tissue tumors of the head and neck collected between 1959 and 1984 were retrieved and reclassified. 562 out of 646 tumors (87%) were benign. Three quarter of these growths could be diagnosed as nerve sheath tumors (schwannomas and neurofibromas), hemangiomas, fibrohistiocytic tumors and lipomas. 84 tumors were malignant (13%). As the most frequent subtypes we found fibrohistiocytic sarcomas (malignant fibrous histiocytomas and atypical fibroxanthomas), muscularly differentiated sarcomas (rhabdo- and leiomyosarcomas) and unclassified sarcomas. The age and sex distribution as well as the localization and histologic peculiarities were analysed and compared with findings reported in the literature. The significance of knowing such data for diagnostic and differential diagnostic considerations is stressed and exemplified.

Adult↗
PubMed1986

[Papillary endothelial hyperplasia. Diagnosis and differential diagnosis].

There are only a few reports of papillary endothelial hyperplasia in the literature. Familiarity with the entity is important for the differential diagnosis of vascular tumors. The authors analyzed seven cases of papillary endothelial hyperplasia morphologically. Characteristic features include intravascular, endothelial-covered, papillary formations of varying size. Cellular atypia, pathologic mitotic figures and necrosis were absent. The presence of a single-layered endothelium and uniform cellularity as well as the absence of invasivity contribute to the differential diagnostic distinction from low grade angiosarcoma. The immunohistochemical demonstration of Factor VIII-associated antigen in the proliferative endothelium helps to demarcate the lesion in the event of the simultaneous occurrence of non-vascular mesenchymal tumors (3 cases). The pathogenesis of papillary endothelial hyperplasia is unknown. The possibility of a relation to thrombus organization and/or hormonal factors is discussed.

Adult↗
PubMed1986

[Melanocytic schwannoma. Light-and electron microscopic findings on the morphology, diagnosis, and differential diagnosis].

A melanocytic schwannoma was extirpated from the posterior mediastinum of a ten-year old girl The tumor consisted of cells which were spindle-shaped to polygonal in shape. Spindle-shaped cells were arranged in short, somewhat curved fascicles. In some areas a strand-like arrangement of cells gave rise to an epithelioid appearance. Typical features of benign schwannomas such as nuclear palisading and myxoid texture were absent. The essential histologic hallmarks were melanin deposition and the presence of small psammoma body-like, calcified spherules. Electron microscopic examination confirmed the schwannian differentiation of the tumor cells. These features included interlocking cellular processes, along with a tendency to display the wrap-around phenomenon and a sometimes multi-layered lamina externa. Intracytoplasmic melanin synthesis was evidenced by demonstration of melanosomes in different phases of maturation. The differential diagnosis is discussed with particular emphasis on the need to distinguish this tumor from malignant melanoma. Melanocytic schwannomas should be regarded as potentially malignant. The tendency and degree of invasiveness, mitotic frequency and the ability of tumor cells to form lamina externa have the greatest prognostic value.

Child↗
PubMed1986

[Olfactory neuroblastoma. Clinical course, light microscopic and ultrastructural findings in 3 cases].

Olfactory neuroblastomas are considered to be a clinicopathological entity, but they may show variable histologic pictures. The light and electron microscopic features of 3 cases as examples for the possible range of morphological findings are presented. This report is also aimed at defining essential diagnostic features, at discussing the differential diagnosis and finally at making pathologists more familiar with these rare tumors. The clinical appearance of the three cases was more or less typical for olfactory neuroblastomas. The leading symptom in all patients was a nasal obstruction. Light microscopically, the neuroblast-like tumor cells were arranged in sheaths or nests. Only in case 1 there were some Flexner rosettes, and especially in case 2 numerous Homer-Wright pseudo-rosettes could be found. Somewhat spindled cells with resemblance to Schwann cells were recognized in case 1 and 3. Neither argyrophilia nor argentaffinity could be demonstrated. Neuroblast-like tumor cells in case 2 contained glycogen intracytoplasmically. The diagnostically essential electron microscopic characteristics were neurite-like cellular processes and neurosecretory granules within the cytoplasm. Corresponding to light microscopic findings in cases 1 and 3, cells with features of Schwann cells could be identified. From the literature and the results presented here the conclusion can be drawn, that in nearly all cases a definite diagnosis is possible if besides the histologic picture also clinical data and, if necessary, ultrastructural and immunohistochemical findings are considered. The most important light microscopic criteria are a fine-fibrillary intercellular substance and the occurrence of Homer-Wright pseudo-rosettes. The differential diagnosis of olfactory neuroblastomas with special regard to electron microscopic findings is discussed and some remarks on the clinical behaviour are added.

Adult↗
PubMed1986

[Olfactory neuroblastoma. 3 case reports as a contribution to the clinical aspects, morphology and prognosis].

The leading symptom in all patients was a nasal obstruction. At first all three cases of olfactory neuroblastoma were mistaken for polyposis nasi. The tumour can be diagnosed solely by histologic examination. The light microscopic as well as the ultrastructural findings demonstrated the great morphological variability of this carcinoma. In nearly all cases a definite diagnosis is possible if besides the light microscopic picture also clinical data, ultrastructural and, if necessary, immunohistochemical findings are considered. At the time of diagnosis one tumour was Kadish-stage A and two were stage C. Lokal and metastatic tumour extension, recurrence of disease after treatment, patient age and radical tumour resection at initial presentation, are prognostic important criteria. The discriminant function by Homzie and Elkon permits the oncologist to predict the patient's outcome accurately.

Adult↗
PubMed1985

Connective tissue reactions in early phases of spontaneous regression of experimental malignant histiocytomas. An electron microscopic study.

Interactions between cancer and host are said to comprehend immunologic processes and stromal reactions including an angiofibroblastic response. We studied the latter phenomenon in spontaneously regressing experimental malignant histiocytomas produced by inoculation of an established macrophage-like cell line (WEHI-3) into baby rats. Light and electron microscopic investigations of the tumor tissue showed that there was a clear proliferation of fibroblasts and capillary vessels beginning from the 8th-10th day of the experiment. The vascular structures seemed to be somewhat changed and fibroblasts often displayed close contacts to tumor cells. The significance of these connective tissue reactions is discussed and, finally, the observations led to the conclusion that the angiofibroblastic reaction in the malignant histiocytoma model presented here may actively contribute to tumor breakdown and should not be interpreted as being only a secondary phenomenon after irreversible damage of tumor cells.

Animals↗
PubMed1985

[Electron-microscopic study of monophasic spindle-cell synovial sarcomas].

Ultrastructural analysis of 9 monophasic spindle-cell synovial sarcomas revealed both undifferentiated tumour cells and histiocyte-like and fibroblast-like elements. Specialized contacts between tumour cells are found in 8 tumours, formation of the cavities of varying size (including vessel-like structure in 2 cases) in 7 tumours. Other findings included a discontinuous external lamina in 4 tumours; filopodium-like cell protrusions in 5, and spindle-shaped collagen bundles with long striation in 2 cases. The observation of cell contacts and cavities is of a diagnostic importance for monophasic synovial sarcoma. The differential diagnosis of these sarcomas and other spindle-cell tumours is discussed. Ultrastructural findings are interpreted as evidence of the monophasic spindle-cell synovial sarcoma origin from mesenchymal stem cells.

Adolescent↗
PubMed1985

[Pigment-free clear-cell sarcoma].

Clear-cell sarcoma of tendons and aponeuroses is an infrequent soft tissue sarcoma. Although this sarcoma is now accepted as a clinico-pathological entity and is well-defined clinically, questions on the histogenesis are still under discussion. Because of the possible presence of melanin pigment the idea was put forward that these tumors may be soft tissue melanomas. The authors studied a clear-cell sarcoma without melanin pigment and found at the ultrastructural level that the tumor cells often showed a basal lamina-like material in the vicinity of their cell membranes and were inclined to wrap around extracellular structures. They were in part connected to another by desmosome-like junctions and occasionally contained membrane-bound dense bodies resembling neurosecretory-type granules. Pinocytosis and glycogen were lacking. The results of electron microscopic examination showed this tumour to be closer to the malignant schwannoma rather than melanoma: histogenetically it is obviously linked to the neural crest.

Adult↗
PubMed1985

[Primary soft tissue tumors of the epididymis, paratesticular tissue and spermatic cord].

The present study comprises 23 primary soft tissue tumors of the epididymis, paratesticular tissue and of the spermatic cord. These tumors were reclassified according to the diagnostic criteria of the WHO. The most common tumor of the paratesticular tissue is the adenomatoid tumor (65%), followed by the leiomyoma (17%). Other recognized tumors are: two typical lipomas, one lipo- and one leiomyosarcoma. Because of its relatively high frequency the adenomatoid tumor is reviewed more in detail with regard to its morphology and histogenesis. Some problems of the clinical pathology of paratesticular soft tissue tumors are briefly discussed.

Adult↗
PubMed1985

[Neuroendocrine (Merkel cell) skin cancer. Electron microscopic study].

The study is concerned with the results of light and electron microscopic examination of 2 cases of neuroendocrine (Merkel cell) carcinoma of the skin. Both patients developed multiple widely-distributed intra- and subcutaneous nodules. Histologically, tumors were mostly trabecular. Electron microscopic examination revealed neuroendocrine secretory granules, small bundles of intermediate fibers, a well-defined Golgi complex and a relatively high level of vesicular structures. There were some basal membrane fragments. It is suggested that they originate from polypotential epithelial stem cells.

Aged↗
PubMed1984

Multiple neuroendocrine carcinomas (so-called Merkel cell tumours) of the skin. Report on two cases with unique clinical course.

Two neuroendocrine carcinomas of the skin (so-called Merkel cell tumours) are presented. In both cases multiple tumour nodules developed within the course of the disease. The light and electron microscopic observations correspond with the findings reported in other neuroendocrine carcinomas. As a variable morphological and clinical pattern for these tumours seems to exist we consider our two cases with their unique clinical picture to be an obviously infrequent variant of this tumour disease, we propose for it the term "multiple neuroendocrine carcinoma syndrome".

Adenocarcinoma↗
PubMed1984

[Myofibroblasts in the stroma of colonic tumors].

An ultrastructural examination of 18 colonic carcinomas detected myofibroblasts in 13 tumors. An inverse correlation was established between the level of myofibroblasts and the number of inflammatory cells. A multi-layered vascular basal membrane was found in the capillary vessels of 5 carcinomas. Myofibroblasts were invariably accompanied by altered smooth muscle cells corresponding to pericytes with smooth muscle traits. The findings suggest that myofibroblasts may develop from fibroblasts, smooth muscle cells of the intestinal wall and cells of vascular structures.

Capillaries↗
PubMed1984

Ultrastructural observations of the stroma of human colon carcinomas with special regard to myofibroblasts.

The stroma of 18 human colon carcinomas was studied with regard to the occurrence of myofibroblasts. In addition, we tried to determine if there was any relationship between myofibroblasts and other stromal responses to tumor growth, e.g. immunologic inflammatory reactions or activation of vascular structures. We found myofibroblasts in 13 carcinomas, although only sporadically in 6 of them. In 5 carcinomas these cells were absent. The number of myofibroblasts showed an inverse relation to the quantity of inflammatory cells (mainly lymphocytes, plasma cells and histiocytes). A variable amount of activated vascular structures could be seen in all cases. In 5 tumors many activated vessels showed a multilayered basement membrane. The electron microscopic findings led to the conclusions that myofibroblast proliferation and immunologic inflammation are not positively correlated with each other and that vascular activation does not parallel myofibroblast induction. The significance of the individual components for tumor prognosis is briefly discussed and the need for further work to clarify the role and mode of interaction of the different factors in tumor-induced stromal response is emphasized.

Adenocarcinoma↗