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M Tötsch

Publications and source records attributed to M Tötsch.

At least 19 recordsLinked to original sources

[Thyroid tumors].

The vast majority of thyroid tumours are epithelial. In contrast to thyroid adenoma, which is a common tumour, thyroid carcinomas make up only 1% of all human malignancies. Routine pathology is regularly confronted with a differential diagnosis involving thyroid adenoma and carcinoma, as well as particular variants of these tumours. This paper deals with the standardised gross and histological examination, as well as the impact of immunohistochemistry and intraoperative frozen sections on thyroid pathology.

Carcinoma, Papillary↗

Adrenal cortical phaeochromocytoma: a case report of a rare entity.

Adrenal cortical phaeochromocytomas (pseudo-phaeochromocytomas) are a very rare entity and a diagnostic challenge. Of the few cases previously reported, most have incomplete data or lack clinical and biochemical follow-up documenting the cure of the excess secretion of catecholamines after resection of the tumour. We report herein a 62-year-old patient with clinical and biochemical findings diagnostic of a phaeochromocytoma associated with a 2-cm adrenal mass on CT scan. Surgery revealed the presence of an adrenal cortical adenoma with positive staining for the neuroendocrine marker synaptophysin, but negative for chromogranin, as has been previously reported for these rare cortical phaeochromocytomas. After removal of the tumour the clinical symptoms resolved and biochemical markers normalized, demonstrating the causal relationship between the cortical tumour and the excess production of catecholamines.

Adrenal Cortex Neoplasms↗

Feasibility of the new WHO classification of pulmonary neuroendocrine tumours.

Primary pulmonary neuroendocrine tumours present a heterogeneous group of tumours causing problems in diagnosis and treatment. The new WHO classification of lung tumours was published in 1999 in order to improve this situation by combining morphology, immunohistochemistry and clinical background for diagnosis. The aim of our study was to evaluate the feasibility of this classification and to discuss the consequences of modified diagnostic criteria. 50 cases of neuroendocrine tumours and 50 poorly differentiated lung tumours diagnosed in the years 1981-1994 were independently evaluated by three pathologists. The diagnosis of all 27 typical carcinoids (TC) was given by all authors, however, no unanimous agreement was achieved in one of three atypical carcinoids (AC) and two of four large cell neuroendocrine carcinomas (LCNEC). While typical and atypical carcinoids can be distinguished by the number of mitoses or presence of necrosis it was found that the most difficult diagnostic factor for large cell neuroendocrine carcinoma is the recognition of its light-microscopic neuroendocrine features. In consequence it must be distinguished not only from atypical carcinoid or small cell lung carcinoma (SCLC), but also from poorly differentiated carcinoma. Immunohistochemistry is important for the diagnosis of this entity but also for nonsmall cell lung carcinoma with neuroendocrine differentiation (of which 1 case was detected in our series) There was agreement on the diagnosis of small cell carcinomas in all but one case. The results indicate the excellent reproducibility of the WHO classification.

Feasibility Studies↗

Mesenteric cysts. Toward less confusion?

OBJECTIVE: Mesenteric cysts are rare intra-abdominal masses generally omited or briefly reported in textbooks. Their rarity had fostered a lack of information and difficulty in classification. The goal of the study is to present a simple, comprehensive, and reproducible classification of mesenteric cysts. METHODS: A large review of the literature with particular attention to recent series was performed in order to identify and characterize the different groups of mesenteric cysts. RESULTS: Although cysts of lymphatic and mesothelial origin are those most frequently encountered, they were confounded or omitted in previous classifications. However, their distinction is important because their incidence and mode of presentation differ. Lymphangiomas predominate in male children, may cause acute abdominal pain, and frequently require resection of adjacent structures. In contrast, cysts of mesothelial origin such as benign cystic mesothelioma are seen more frequently in young and middle-aged women, usually present with more indolent symptoms, and often recurs. CONCLUSIONS: A new classification based essentially on histopathological features should include the 6 following groups: (1) cysts of lymphatic origin (simple lymphatic cyst and lymphangioma); (2) cysts of mesothelial origin (simple mesothelial cyst, benign cystic mesothelioma, and malignant cystic mesothelioma); (3) cysts of enteric origin (enteric cyst and enteric duplication cyst); (4) cysts of urogenital origin; (5) mature cystic teratoma (dermoid cysts), and (6) pseudocysts (infectious and traumatic cysts).

Diagnosis, Differential↗

PCR based detection of mycobacteria in paraffin wax embedded material routinely processed for morphological examination.

BACKGROUND: The incidence of mycobacterial infections has increased during the past five years. A prompt diagnosis is indispensable for initiating appropriate treatment. Because culturing of mycobacteria takes three to six weeks and sensitivity of microscopic detection of acid fast bacilli is low, amplification methods provide promising possibilities. Recently, the polymerase chain reaction (PCR) has been shown to be useful for confirming a mycobacterial infection, especially in cases with unexpected histological findings or lack of suitable material for culturing. AIMS: To evaluate the impact of PCR based techniques in the detection of mycobacterial infections in uncultured routine histological specimens as an alternative to surgical pathology. METHODS: Two hundred and twenty nine formalin fixed and paraffin wax embedded samples from 141 patients with clinical or histological suspicion of a mycobacterial infection were investigated using three different PCR assays and Southern blotting. PCR results were compared with histology and culture and the patients' clinical findings. RESULTS: When using culture as the reference method, the sensitivity for the detection of mycobacteria of the tuberculosis complex was 90%, specificity was 92%, the positive predictive value was 81%, and the negative predictive value was 96%. The sensitivity for the detection of nontuberculous mycobacteria was 100% and specificity was 78%, the positive predictive value was 26%, and the negative predictive value was 100%. The patients' clinical findings supported the PCR positive results, indicating a mycobacterial infection in 11 of 18 initially culture negative cases and in 21 of 35 PCR positive cases without culture results. CONCLUSIONS: These results indicate that PCR based techniques are sensitive, specific, and rapid methods for the detection of mycobacteria in routinely processed paraffin wax embedded and formalin fixed histological samples.

Blotting, Southern↗

Duodenal tuberculosis presenting as acute ulcer perforation.

Gastrointestinal tuberculosis (TB) is rare, but its incidence is increasing in industrialized countries because of the growing numbers of individuals at risk for TB. Herein, we report the exceptional case of a young, HIV-negative, African refugee who presented with acute perforation of an isolated duodenal tuberculous ulcer. Clinical patterns of duodenal TB are discussed. The difficulty of obtaining a diagnosis on the basis of clinical features, endoscopy, and imaging is emphasized, as well as the importance of obtaining a biopsy specimen and its limitations.

Acute Disease↗

Incidence and clinical characteristics of thyroid carcinoma after iodine prophylaxis in an endemic goiter country.

Iodized salt prophylaxis has been performed in Austria since 1963. Through this approach, mean urinary iodine excretion has been normalized to 144+/-23.5 microg/g creatinine per day. Thus Tyrol is no longer an endemic goiter area. We have analyzed the impact of iodized salt prophylaxis on thyroid cancer (TC) comparing data from the early 1960s with those corresponding to the period 1986 to 1995, when iodine supply was normalized. The study included 439 patients from Tyrol and Southern Tyrol. The incidence of TC in Tyrol has risen during the past decades from 3.07 between in 1957 and 1970 to 7.8 between 1990 and 1994 (CR/100000/year). We observed a rise in the percentage of differentiated adenocarcinomas (56% to 91.5%) with a predominance of papillary TC (54.4%) along with a decrease of anaplastic TC. In addition to these histological features, a shift to less advanced TNM stages, eg, T1-3, N0-1a, M0, was obvious, increasing from 29% to 72.2%, whereas advanced tumors, ie, T4 or N1b or M1, decreased from 71% to 28%. These changes have significantly improved prognosis. The current 5-year survival rate is 90.7% as compared with a rate of 73% in the 1960s; the values for 7-year survival are 89% and 48%, respectively. The marked effects of age, tumor stages, and histology on prognosis were confirmed with the Kaplan-Meier method. We conclude that together with normalization of iodine supply in an endemic goiter region the epidemiological profile of TC has changed. Even though the incidence of TC has risen, prognosis has significantly improved due to a shift towards differentiated forms of TC that are diagnosed at earlier stages.

Age Factors↗

Diagnostic value of different PCR assays for the detection of mycobacterial DNA in granulomatous lymphadenopathy.

Diagnosis of mycobacterial infection is made by assessment of characteristic histological features, staining of acid-fast bacilli, or agar culture. Recent advances in molecular biology have provided alternative approaches for the detection of mycobacteria, but only limited data are available dealing with the comparative evaluation of these methods. In order to determine the diagnostic applicability of polymerase chain reaction (PCR)-based assays, 20 formalin-fixed and paraffin-embedded lymph nodes with bacille Calmette-Guérin (BCG) lymphadenitis were investigated which in Löwenstein Jensen agar culture were either positive or negative (ten cases each); ten lymph nodes with non-specific lymphadenitis served as negative controls. Ziehl-Neelsen staining as well as three different PCR assays (including nested PCR), amplifying a specific sequence of the Mycobacterium tuberculosis complex or sequences of the 65 kD antigen gene, were performed. Positive culture was only obtained from lymph nodes which had been surgically removed within 20 weeks after vaccination (P < 0.001). In contrast to microscopic examination, which yielded no more information than agar culture, PCR detection of mycobacterial DNA was unrelated to culture findings. Combined use of different assays, as well as DNA extraction from at least three paraffin sections from each specimen, resulted in the detection of mycobacterial DNA in all lymph nodes with amplifiable DNA (18 out of 20 cases). Controls remained consistently negative. Thus, the combined use of different PCR assays is proposed as a rapid and sensitive technique for the detection of mycobacterial DNA in formalin-fixed and paraffin-embedded tissue.

Axilla↗

Simultaneous transplantation of isolated hepatocytes reduces rejection of small bowel allografts and improves survival in the rat.

Hepatocytes transplanted some days prior to vascularized allografts were shown to have the potential to prolong allograft survival in the rat. In the present study, hepatocytes and small bowel allografts were transplanted simultaneously in a Lewis (donor)-Brown Norway (recipient) rat model. 8-15 x 10(6) liver cells were injected into the spleen of small bowel recipients. The administration of at least 10 mg cyclosporine A (CyA)/kg over 3 days was necessary to prevent early rejection of hepatocytes. In groups simultaneously receiving hepatocytes, small bowel grafts and 10 mg CyA/kg over 3 days, a significant mitigation of rejection and a prolongation of survival was achieved, compared to groups receiving solely small bowel grafts and 10 mg CyA/kg over 3 days. We conclude that simultaneously transplanted hepatocytes exert a protective effect on a grafted organ from the same donor, provided that early rejection of hepatocytes is prevented by sufficient immunosuppression.

Animals↗

Endophthalmitis induced by atypical mycobacterial infection.

Granulomatous uveitis induced by Mycobacterium tuberculosis infection has been less frequently encountered over the last 20 years. Differential diagnosis of M. tuberculosis and other atypical mycobacteria is nevertheless of particular interest in patients with acquired immune deficiency syndromes. We present the case of a 60-year-old man who was referred to our clinic because of therapy-refractive endophthalmitis. Diagnostic vitrectomy including microbiological examination as well as further extensive serological examinations did not reveal any further information on the etiology. Despite intensive anti-inflammatory treatment, the eye became blind and developed secondary glaucoma. Evisceration of the globe had to be performed. Histopathological examination showed a granulomatous inflammation without the tuberculosis-typical development of central caseous necrosis. Further molecular pathological investigations had to be performed with regard to differential diagnostic aspects. By means of the polymerase chain reaction we could detect mycobacterial gene sequences that corresponded to atypical mycobacteria. The diagnosis of atypical mycobacterial infection was confirmed Molecular-genetics examination techniques, especially those involving the polymerase chain reaction, will become more important in routine histopathological examination. These techniques can be performed on paraffin-fixed or formalin-embedded material for further differential diagnostic considerations.

Antigens, Bacterial↗

Standardized staining and analysis of argyrophilic nucleolar organizer region associated proteins (AgNORs) in radically resected colorectal adenocarcinoma--correlation with tumour stage and long-term survival.

Quantification of silver-stained nucleolar organizer region associated proteins (AgNORs) was introduced in histopathology as a marker of cellular and nucleolar activity. However, due to the poor staining quality obtained on routinely processed archival material, the method yielded controversial and sometimes non-reproducible results. The recent introduction of wet autoclave pretreatment has reliably improved AgNOR staining quality on routinely formalin-fixed and paraffin-embedded tissues. In the present study, 92 routinely processed colorectal carcinomas were investigated, applying this novel staining technique. Subsequent standardized morphometric analysis revealed, irrespective of common tumour staging or grading classifications, a statistically highly significant correlation between AgNOR parameters and clinical course. The usefulness of standardized AgNOR parameters for the independent prediction of patient survival was proven by uni- and multivariate analysis.

Adenocarcinoma↗

Identification of mycobacteria to the species level by automated restriction enzyme fragment length polymorphism analysis.

An automated method for the restriction fragment length polymorphism (RFLP) analysis for the differentiation of mycobacteria to the species level is described. After polymerase chain reaction (PCR) amplification of a sequence of the gene encoding the 65-kDa surface antigen common to all mycobacteria the product was investigated by RFLP analysis. For accurate determination of fragment sizes the asymmetrically fluorescein-labelled PCR product was partially digested with restriction site enzymes BstEII and HaeIII. The fragments obtained were analysed electrophoretically using an automated laser fluorescence DNA sequencer. Determination of fragment sizes revealed a deviation of +/- 1 base pair (bp; 0.6%) when compared to expected sizes. The validity of this approach was confirmed by analysing mycobacterial DNA obtained from pure cultures of Mycobacterium (M.) tuberculosis and alcohol-fixed smears as well as paraffin-embedded sputa of patients with culture-proven tuberculosis. Additionally a diagnostic algorithm was established by investigation of cultured M. bovis, M. bovis bacille Calmette-Guérin, M. avium, M. intracellulare and M. fortuitum. The method allows the identification of restriction enzyme sites which are only 40 bp apart. Partial restriction enzyme digestion of asymmetrically fluorescence-labelled PCR products will presumably lead to the discovery of new restriction enzyme sites.

Algorithms↗

Reduced CD21 (CR2) and CD54 (ICAM-1) expression in MT2 cells with HIV-1 or HIV-2 strains.

Alterations in the expression of cell-surface receptors have been reported in HIV-infected cells for CD4, CD25 (IL-2 receptor), CD2, CD3 and CD8 and CD26. In the present study we provide evidence that CD21 is down-regulated in the human T-lymphoblastoid cell line MT2 after infection with HIV-1 and -2 isolates. The same effect was observed with ICAM-1 (CD54). CD21 expression was monitored by means of fluorescence intensity, its functional ability to bind to C3d and by quantitative measurement of CD21-antigen in supernatants and cell lysates using an immunoassay. In addition, the decrease of CD21 and ICAM-1-specific mRNA suggests a mechanism at a transcriptional level. Our data suggest that HIV might have a direct influence on the receptor expression.

Cell Line, Transformed↗

Immunohistochemically detectable bcl-2 expression in colorectal carcinoma: correlation with tumour stage and patient survival.

The bcl-2 gene encodes for a mitochondrial membrane proto-oncoprotein, the expression of which is known to suppress programmed cell death (apoptosis). In the present study the prognostic value of bcl-2 proto-oncoprotein was immunohistochemically investigated in a series of 104 colorectal carcinomas. The bcl-2 staining patterns were semiquantitatively assessed and correlated with the pTNM stage, Dukes' classification, lymphocytic infiltration (Jass classification) and tumour grade as well as parameters not associated with prognosis (gender, age, tumour site, histological tumour type). Statistical analysis was carried out using the Kaplan-Meier method, the log-rank test, hazard ratios and their confidence intervals. Fifty-five out of 104 cases completely lacked immunohistochemical bcl-2 expression. Fewer than 5% of bcl-2-positive cells were found in 25, 5-50% in 17 and more than 50% in five cases. The extent of bcl-2 expression by tumour cells decreased significantly with respect to increasing tumour size (P < 0.05), decreasing lymphocytic infiltration (P < 0.05) and chance of poor clinical outcome (P < 0.05), but not with worsening of Dukes stages. In multivariate analysis (Cox regression model) bcl-2 expression remained as an independent prognostic parameter with Dukes' classification as stratification factor (P < 0.001). Although the biological functions of bcl-2 protein are not yet well understood, our results provide further evidence that bcl-2 oncoprotein appears to be associated with favourable clinical outcome. Thus immunohistochemical bcl-2 phenotyping of colorectal carcinoma may contribute in future to the clinical management of these patients.

Adult↗