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J Kracht

Publications and source records attributed to J Kracht.

At least 19 recordsLinked to original sources
PubMed1988

Osteoclast-type giant cell tumour of the pancreas.

Two cases of osteoclast-type giant cell tumour of the pancreas (OGTP) are presented and compared with similar tumours of other locations and pancreatic carcinomas. One of the tumours was analyzed by immunohistochemical methods. The mononuclear stromal cells and osteoclast-like giant cells, which characterize this very rare neoplasm, reacted with an antibody against vimentin, but were not decorated by antibodies against lysozyme, alpha-1-ACHT, alpha-1-AT. Pleomorphic mononuclear cells in osteoid additionally contained osteonectin and could thus be identified as osteoblasts. Only the tumour glands stained positively with panepithelial keratin antibodies and antibodies against the keratin polypeptides 7, 18, 19. These results demonstrate for the first time the mesenchymal differentiation of the OGTP, which in some cases is also able to form epithelial structures. The immunohistochemical reactions and the characteristic morphology of the tumour show the OGTP to be an entity which must be differentiated from pancreatic carcinoma, especially from its giant cellular subtype.

Aged↗
PubMed1988

Immunohistochemical hormone content in medullary and undifferentiated thyroid carcinoma and prognosis after surgery.

Immunohistochemical determinations in tissue specimens of medullary and "undifferentiated" thyroid carcinomas were carried out with antisera against calcitonin, calcitonin-gene related peptide (CGRP), somatostatin, and also thyroglobulin, using the PAP method. All 8 samples of medullary carcinoma stained positive with antisera against calcitonin and CGRP, 7 samples were also positive for somatostatin. Out of 22 cases initially diagnosed as "undifferentiated thyroid carcinoma" 3 revealed positivity for calcitonin, 2 for CGRP, and 1 for somatostatin. Congo red stain for amyloid, performed several years ago in 2 of these 3 cases, had been negative. The patients with medullary carcinoma survived longer than those with "undifferentiated" carcinoma. One patient of the latter group, but with calcitonin, CGRP, and somatostatin immunoreactivity in the tumour tissue, is now alive and well, more than 4 a after initial treatment.

Amyloid↗
PubMed1985

What's new in endocrine factors of tumor growth?

In this review some aspects of endocrinological factors in cancer are discussed. The first part addresses the determination of steroid hormone receptors in cancer of the breast. The importance of steroid hormone receptor determination for the clinical management of breast cancer patients is emphasized. Current methods for receptor measurement are critically evaluated and it is concluded that rigorous standardization of tissue handling procedures and of radiochemical methodology is mandatory to improve the reliability of the presently available methods. The development of new techniques for receptor determination has been met with high expectations. Monoclonal antireceptor antibodies in principle allow the development of a radioimmunoassay but are not widely available as yet. Histochemical methods for receptor localization have so far failed to meet accepted criteria of specificity. Therefore radiochemical determination at present remains the only reliable method. The second part addresses the production of peptide hormones by endocrine tumours of the gastroenteropancreatic (GEP) system and by non-neuroendocrine neoplasms. In the endocrine tumours of the GEP system a wide range of peptide hormones can be detected by immunocytochemistry, but most frequently the pattern of hormone production is comparable with that in the normal organ of origin. Clinical symptoms of excess hormone production occur much less frequently than hormone production is found by immunological methods and is usually caused by one hormone. It is proposed that these neoplasms are classified according to the hormone which causes the leading clinical symptoms and/or the hormone with the highest serum level. Peptide hormone producing cells in classical carcinoma are an intriguing phenomenon which has shed some new light on the embryological origin of neuroendocrine cells in the relevant organs and also on the histogenesis of neuroendocrine as well as non-neuroendocrine neoplasms.

Adenoma, Islet Cell↗
PubMed1984

Sarcoma of the lung in a pacemaker pocket--simple coincidence or oncotaxis?

An 82-year-old man developed a soft-tissue sarcoma in the subpectoral pocket of a titanium-covered pulse generator that had been replaced 8 months previously without evidence of tumor. The tumor represented a metastatic manifestation of a malignant fibrous histiocytoma situated in the contralateral lower pulmonary lobe. The patient died some weeks postoperatively due to cachexia. Autopsy revealed no further metastases. The appearance of cancer in patients with pacemakers is probably coincidental and not related to material or electrochemical stimulation, although the site of the generator pocket might be oncotactic because of the irritation that would trap tumor cells and provide disruption in the intracellular endothelial barrier allowing migration of the tumor cells into tissues. Possible causes and relationships are reviewed.

Aged↗
PubMed1982

Ultrastructural, biochemical, and cell-culture studies of a presumed extraskeletal Ewing's sarcoma with special reference to differential diagnosis from neuroblastoma.

The history of a 6-year-old girl with a tumor originating from thoracic spine and finally becoming resistant to surgery, radio-, and chemotherapy is reported. Tumor-biopsy material was studied by light and electron microscopy, in cell culture, by acetylcholinesterase ultracytochemistry, and by quantitative catecholamine analysis and this led to the rejection of the initial diagnosis of a neuroblastoma. Light microscopy revealed a uniform population of undifferentiated cells incompletely lobulated by broad fibrovascular septa. Using the electron microscope, cells were characterized by large intracellular pools of glycogen, little cytoplasm with an abundance of free ribosomes and a paucity of organelles. A few cells displayed desmosome-like attachment sites. Staining for specific and unspecific acetylcholinesterase was negative with light and electron microscopy, as were the results of catecholamine histofluorescence using the glyoxylic acid method. The latter result was confirmed by the negative outcome of quantitative analyses of dopamine, noradrenaline, and adrenaline with high pressure liquid chromatography nd electrochemical detection in tissue samples. Tumor cells could easily be maintained in culture for up to 4 weeks. None of a variety of treatments that are known to favor expression of neuronal characteristics in neuroblastoma cells (serum withdrawal, nerve growth factor, dbcAMP, dexamethasone) induced morphological differentiation in cultured tumor cells. On the basis of the clinical history, morphology, and of our experiments with tumor cells, the diagnosis of a so-called extraskeletal Ewing's sarcoma is most likely. Our results strengthen the view that a cell biology approach may be valuable in neuroblastoma differential diagnosis.

Acetylcholinesterase↗