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P Stosiek

Publications and source records attributed to P Stosiek.

At least 19 recordsLinked to original sources
PubMed2001

Discordance between K-ras mutations in bone marrow micrometastases and the primary tumor in colorectal cancer.

PURPOSE: To study bone marrow micrometastases from colorectal cancer patients for the presence of K-ras mutations and to compare their genotype with that of the corresponding primary tumor. PATIENTS AND METHODS: Bilateral iliac crest aspiration was performed in 51 patients undergoing surgery for colorectal cancer, and bone marrow micrometastases were detected by immunohistochemistry. The presence of K-ras mutations was determined by single-strand conformation polymorphism analysis on both primary tumors and paired bone marrow samples and was confirmed by sequencing. RESULTS: In six patients with primary tumor mutations, it was possible to amplify a mutated K-ras gene also from the bone marrow sample. In three of those patients the pattern of K-ras mutations differed between both samples, in two patients the mutation was identical between the bone marrow and its primary tumor, and in one patient the same mutation plus a different one were found. Fifteen of 17 K-ras mutations found in primary tumors were located in codon 12, whereas in bone marrow, five of seven mutations were found in codon 13 (P =.003). CONCLUSION: Our results demonstrate that, at least for K-ras mutations, disseminated epithelial cells are not always clonal with the primary tumor and they question the malignant genotype of bone marrow micrometastases. They also indicate that different tumoral clones may be circulating simultaneously or sequentially in the same patient. Analysis of the type of mutations suggests that cell dissemination might be an early event in colorectal carcinogenesis.

Aged↗
PubMed2000

[Diagnostic importance of flow cytometry in staging malignant lymphoma].

Bone marrow biopsy plays an important role in the clinical diagnosis of malignant lymphoma. Further diagnostic methods need to be established to increase accuracy in the light of advances over recent years in the immunophenotypical characterization of discrete lymphatic bone marrow lesions and the continuing difficulty in classifying them. This study compared the diagnostic value of flow cytometry to that of conventional bone marrow biopsy in 156 patients with 191 marrow biopsy specimens or bone marrow aspirates. The most important findings were that up to one-third of lymphomas could not be diagnosed by flow cytometry, and that the degree of infiltration was estimated as less than two-thirds. However, flow cytometric results were more satisfactory in acute lymphoblastic leukemia, lymphoblastic lymphoma, hairy cell leukemia, and chronic lymphocytic leukemia. In summary, flow cytometry has a complementary role in the staging of lymphoma but cannot fully replace conventional trephine biopsy.

Biopsy↗
PubMed1999

Phenotypic characteristics of cell lines derived from disseminated cancer cells in bone marrow of patients with solid epithelial tumors: establishment of working models for human micrometastases.

Bone marrow (BM) is a clinically relevant site of micrometastatic disease in patients with solid epithelial tumors. It is, therefore, important to establish suitable models that allow the in-depth characterization of disseminated tumor cells present at low frequencies of 10(-5)-10(-6) nucleated BM cells. The aim of this study was to assess common phenotypic features of nine tumor cell lines established from BM of patients with cancer of the prostate (four cell lines), breast (two cell lines), lung (two cell lines), and colon (one cell line) using immunocytochemistry, flow cytometry, and reverse transcription-PCR. All cell lines stained positive for both cytokeratins, the epithelial intermediate filaments, and the epithelial cell adhesion molecule E-cadherin, and they lacked markers of BM-derived cells. The tumor origin of the cell lines was supported by the expression of the ErbB2 oncogene (seven of nine) and MAGE mRNA (eight of eight). All cell lines coexpressed cytokeratin and vimentin, the mesenchymal intermediate filament, indicating an epithelial-mesenchymal transition of micrometastatic cells. The invasive phenotype of the immortalized cells was also reflected by the consistent expression of several metastasis-associated adhesion molecules, including alpha5 (eight of nine), alpha6 (five of nine), alphaV (nine of nine), beta1 (nine of nine), and beta3 (nine of nine) integrin subunits and the Mr 67,000 laminin receptor (seven of nine). Contrary to our expectations, metastasis-promoting CD44 variant isoforms were only detected on two lines, whereas all cell lines expressed MUC18/melanoma cell adhesion molecule and intercellular adhesion molecule-1, two members of the immunoglobulin superfamily of adhesion molecules that are not frequently found on primary carcinoma cells. The consistent expression of various epithelial and tumor-associated antigens provides evidence that the established cell lines are derived from disseminated cancer cells present in the BM. The invasive phenotype of the immortalized cells was mirrored by their epithelial-mesenchymal transition and the expression of several metastasis-associated molecules, which might be potential candidates for novel therapeutic targets.

Biomarkers, Tumor↗
PubMed1998

Cold acetone fixation and methacrylate embedding. A suitable method for routine processing of bone marrow biopsies.

Here we report that acetone fixation at -18 degrees C with subsequent embedding in methyl-/butylmethacrylate is a reliable method for the routine processing of bone marrow biopsies. This method allows good conventional histological visualization of morphological details, which is comparable with other fixation procedures. The essential advantage of this method is that a wide range of monoclonal antibodies and polyclonal antisera can be used for immunohistochemical investigations for diagnostic and scientific purposes. The addition of 5% polyethylene glycol 400 to the acetone minimizes freeze-related artefacts. The immunohistochemical demonstration of a number of antigens is mostly affected by the medium used for slide preparation and to a lesser extent by the concentration of benzoylperoxide used for polymerization. Performing polymerization at 4 degrees C and using N, N-dimethyl-p-toluidine as accelerator allows the concentration of benzoylperoxide to be reduced to 0.2 g% (8.3 mmol). Under these conditions the methacrylate embedding procedure has only minimal effects on the quality of immuno- and enzyme histochemistry. Additionally, the simplified method for removing the polymerization inhibitor from the methacrylate components and the shortened impregnation step are further advantages of the embedding method described here.

Acetone↗
PubMed1998

Mycobacterium ulcerans infection in a child from Angola: diagnosis by direct detection and culture.

Buruli ulcer, caused by Mycobacterium ulcerans, is a chronic ulcerative skin disease, found predominantly in central and west Africa and Australia. A boy of 2.5 years of age from Angola was admitted to our hospital with severe kwashiokor and a large ulcer with undermined edges on the left side of the thorax. Further examination revealed anaemia, hypoproteinaemia, bacterial superinfection of the ulcer and intestinal parasites. Histological analysis showed acid-fast bacilli and histopathological changes typical of Buruli ulcer. M. ulcerans was detected by PCR and culture. The patient was treated by surgical excision of diseased skin, followed by split-skin grafting. He also received antibiotic therapy (ciprofloxacin, clarithromycin, rifabutin, and dapsone). After six months, the child was discharged from hospital in good condition. This is the first published case of Buruli ulcer from Angola.

Angola↗
PubMed1998

Reduced expression of plakoglobin indicates an unfavorable prognosis in subsets of patients with non-small-cell lung cancer.

PURPOSE: Plakoglobin is thought to play a key role in cadherin-mediated epithelial cell adhesion, because it is a common component of desmosomal and nondesmosomal adherens junctions. Because loss of homotypic cell adhesion is an important early step in invasion and metastasis of solid tumors, we evaluated the frequency and prognostic significance of a deficient expression of plakoglobin in human lung cancer. PATIENTS AND METHODS: At primary surgery, representative specimens of the primary tumor were obtained from 96 consecutive patients with completely resected non-small-cell lung carcinoma (NSCLC) without overt distant metastases. Cryostat sections of these specimens and metastatic lymph nodes were stained with monoclonal antibody (mAb) PG 5.1 against plakoglobin, using an immunoperoxidase technique. Patients were monitored for a median of 39 months (range, 12 to 56) after surgery. RESULTS: Absent or severely reduced expression of plakoglobin (ie, < 30% positive tumor cells) was observed in 39 patients (40.6%). There was no significant correlation to established risk factors, such as the histology, extension, and histologic grade of the primary tumor and metastatic lymph node involvement, or expression of alpha-catenin. Expression of plakoglobin in lymph node metastases ranged from 0% to greater than 60% positive tumor cells. Deficient plakoglobin expression on the primary tumor was significantly correlated to a shortened disease-free and overall survival in patients with adenocarcinomas, pT1-2 tumors, or negative lymph nodes (pN0). In patients with pT1-2 tumors, the independence of this prognostic influence from established risk factors was demonstrated by Cox regression analyses (disease-free survival, P = .002; overall survival, P = .038). CONCLUSION: Deficient expression of plakoglobin appears to be an important event in the progression of NSCLC.

Adult↗
PubMed1997

[Cystic adventitial degeneration of the popliteal artery. Rare cause of intermittent claudication in middle-aged adults].

We report on a 36-year old male patient with clinically prolonged intermittent claudication of the right leg. An operative specimen measuring 8.0 cm of the A. poplitea was sent for examination, which was sheathed by an aneurysmal cyst having a maximal diameter of 1.5 cm. Examination under the light microscope showed an incomplete septated ganglion-like cystic formation with flat connective tissue-like cells or even larger histiocytoid cell elements as inner lining. Immunohistochemically, the cells on the inner lining of the cyst showed to be strongly positive to macrophage marker PG-M1, KP1 and Ki-Mp1. The endothelium of the vessels of the wall of the cyst showed a marked expression of cytokeratin 18. Immunohistochemically as well as in conventional histology, there are general parallels between cysts in cystic adventitial degeneration, ganglia and normal synovia as the two last mentioned tissues also show an expression of cytokeratin 18 at the endothelia of smaller vessels as well as an expression of macrophage-associated antigens on cells of the inner lining. Aetiopathologically, the cysts developing in the course of the disease are rather adventitial ganglia.

Adult↗
PubMed1997

Mucins (MUC1 and MUC3) of gastrointestinal and breast epithelia reveal different and heterogeneous tumor-associated aberrations in glycosylation.

In a comprehensive study, we examined the expression of the membrane and secretory mucins MUC1 and MUC3, respectively, in normal and neoplastic gastrointestinal and breast epithelia before and after specific alterations of their glycan structures by neuraminidase, alpha-fucosidase, or carbohydrate-specific periodate oxidation. MUC1 mRNA was also identified in normal colorectal tissues by in situ hybridization. The data revealed that normal colorectal epithelia express both MUC1 mRNA and protein, which were detectable after periodate oxidation with all tested MUC1-specific antibodies. During tumorigenesis in the colon, MUC1 became recognizable without periodate treatment concomitantly with highly dysplastic lesions and the malignant state. In the breast, in which MUC1 is detectable with most antibodies in normal epithelium as well as in carcinomas, staining could be enhanced by pretreatment with periodate and casually by enzyme treatments. MUC3 was detectable in normal and neoplastic colorectal tissues and was more intensely stained after periodate oxidation. It was absent in normal breast even after pretreatment but was expressed in seven of 20 breast carcinomas. Therefore, incomplete glycosylation, abnormal distribution, and ectopic expression of mucins are characteristics of malignancy. Periodate oxidation may be widely applicable to immunohistochemistry for examining changes in glycosylation and for detecting antigens masked by glycans.

Biomarkers, Tumor↗
PubMed1997

[Adenomatoid tumor of the uterus--2 case reports].

We report two cases of the so-called adenomatoid tumor of the uterus, which have been detected in patients who underwent surgery for leiomyomas. The clinical signs, origin and immunohistochemical characteristics of the adenomatoid tumor are described. Adenomatoid tumors are slow growing epithelioid neoplasias with a co-expression of vimentin and cytokeratins. The characteristic cytokeratins are numbered 7, 8, 18, 19 and 5. The mesothelial histogenesis of the tumor can be confirmed. Our results rule out origins from Müllerian or mesonephrogenous ducts and angioma or adenoma. Considering our experiences, adenomatoid and leiomyoma cannot be distinguished macroscopically. The hysterectomy or salpingo-oophorectomy, primarily performed under other diagnoses, are the therapies of choice.

Adenomatoid Tumor↗
PubMed1996

Thomsen-Friedenreich-related carbohydrate antigens in normal adult human tissues: a systematic and comparative study.

A broad variety of normal human tissues were examined for the expression of Thomsen-Friedenreich (TF)-related histo-blood group antigens, TF (Gal beta 1-3GalNAc alpha 1-R), Tn (TF precursor, GalNAc alpha 1-R), sialosyl-Tn (NeuAc alpha 2-6GalNAc alpha 1-R), considered to be useful in cancer diagnosis and immunotherapy, and sialosyl-TF, the cryptic form of TF. These antigens or, more correctly, glycotopes, were determined by immunohistochemistry with at least two monoclonal antibodies (mAbs) each (except sialosyl-TF) as well as by lectin histochemistry. For a better dissection of sialosyl-TF and TF glycotopes, tissue sections were pretreated with galactose oxidase or the galactose oxidase-Schiff sequence. Staining with mAbs appeared to be more restricted than with the lectins used. Distribution patterns among normal epithelia were different for all four antigens. These antigens were also detected in some non-epithelial tissues. They can be classified in the following sequence according to the frequency of their occurrence in normal tissues: sialosyl-TF > > sialosyl-Tn > Tn > TF. Most of the positively staining sites for TF, Tn, and sialosyl-Tn are located in immunologically privileged areas. The complex results obtained with anti-TF mAbs (after treatment of the tissue sections with sialidase from Vibrio cholerae) and the lectins amaranthin and jacalin revealed a differential distribution of the subtypes of sialosyl-TF [NeuAc alpha 2-3Gal beta 1-3GalNAc alpha 1-R and Gal beta 1-3 (NeuAc alpha 2-6)GalNAc alpha 1-R] in normal human tissues. From our data it can be inferred that TF, Tn, and sialosyl-Tn are promising targets for a cancer vaccine.

ABO Blood-Group System↗
PubMed1996

[Prognostic significance of micrometastases in axillary lymph nodes in breast carcinoma].

We looked for micrometastases in the axillary lymph nodes of 163 women with breast carcinoma, using monoclonal anticytokeratin antibodies. We found 26 micrometastases (2.1%) in node-negative patients (n = 17). Life-table analysis after 3 years detected the conformity of this group with the N1 group with regard to overall survival and distant-metastasis-free survival.

Adult↗
PubMed1996

[Osteomyelitis from Cryptococcus neoformans].

A forty-three-year old patient suspected of having a bone tumor in his left femur, was submitted to the hospital. However, osteomyelitis caused by Cryptococcus neoformans has been demonstrated by culture. The history of the patient revealed a long-term therapy with corticosteroids due to sarcoidosis. The osteomyelitis was treated with fluconazole (200 mg daily p.o.) for three months. Under this therapy the infection resolved.

Adrenal Cortex Hormones↗
PubMed1996

[Expression of plakoglobin in bronchial carcinomas: incidence and significance for disease outcome].

Loss of homotypic cell adhesion is an important prerequisite for invasion and metastasis of epithelial tumor cells. The function of E-cadherin, which mediates epithelial cell-cell adhesion, is regulated by a complex of proteins bound to its cytoplasmic tail, including a-, b-, g-catenins and plakoglobin (PG). The present study was designed to assess whether downregulation of plakoglobin expression occurs in human non-small cell lung carcinomas (NSCLC) and whether this change is associated with an unfavorable prognosis. Using immunohistochemistry with monoclonal antibody (mAb) PG 5.1 to PG, absence or severely reduced expression of PG (i.e., less than 30% of positive tumor cells) was observed in 39 of 97 patients (40.2%) with completely resected primary NSCLC (stages T1-3, N1-2, M0). There was no significant correlation to any of the analyzed clinicopathologic factors such as histologic type, grade or size of the primary tumor, and lymph node involvement. After a median observation period of 39 months (12-56 mo.), univariate Kaplan-Meier analysis showed that patients with PG-deficient primaries tended to have a shortened disease-free survival (p = 0.06). This correlation was statistically significant in patients with adenocarcinomas (p = 0.010), locally restricted primary tumors (pT1/2, p = 0.017), and negative lymph nodes (pN0, p = 0.036). Analysis of the overall survival in these subgroups also revealed significant associations between deficient PG expression and poor outcome (p < or = 0.036). Multivariate analysis was performed for the largest subgroup of patients with pT1/2 tumors (n = 66), demonstrating that PG expression was a strong, independent predictor of tumor relapse (p = 0.002). Thus, deficient expression of PG is a frequent, early event in the progression of NSCLC, which appears to predict an unfavorable prognosis in patients at earlier stages of their disease.

Adult↗
PubMed1995

Glomerulopathy associated with predominant fibronectin deposits: a newly recognized hereditary disease.

A newly recognized type of familial glomerulopathy observed in patients of both sexes in six families is reported. Proteinuria, often within the nephrotic range, microscopic hematuria, hypertension and a slowly decreasing renal function over several years were common. No underlying systemic diseases were identified. Generally, light microscopy showed enlarged glomeruli with minimal hypercellularity and with extensive deposits in the mesangium and subendothelial space. By electron microscopy, granular deposits with some admixture of fibrils were most common. In one family, the deposits were predominantly fibrillary. Immunoglobulins and complement factors were inconstant or lacking. A main finding was a strong immune reactivity to fibronectin, corresponding to the distribution of the deposits. In one patient, the deposits recurred in a renal transplant. There was no indication of systemic deposition. Abnormalities in the metabolism of circulating fibronectin may play a pathogenetic role in this disease of probably autosomal dominant inheritance.

Adolescent↗