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81.
鼻腔恶性黑色素瘤10例临床病理分析   总被引:2,自引:1,他引:2  
目的 探讨鼻腔恶性黑色素瘤的临床病理特征,并对其诊断和鉴别诊断进行讨论.方法 结合组织形态学结构和免疫组化,对10例鼻腔恶性黑色素瘤进行临床病理分析.结果 10例鼻腔恶性黑色素瘤中男性3例,女性7例,年龄52~83岁,平均年龄59.8岁.肿瘤由上皮样,梭形及未分化小细胞等多种类型的细胞组成.免疫组化标记瘤细胞均表达HMB-45、S-100蛋白、vimentin.结论 鼻腔黏膜恶性黑色素瘤易误诊为其它鼻腔原发性肿瘤,导致临床处理不当,延误治疗,与皮肤恶性黑色素瘤相比,鼻腔黏膜恶性黑色素瘤更具有侵袭性、预后差等特点.  相似文献   
82.
Aberrant glycosylation is a common feature of metastatic sub-clones of malignant tumours and in uveal melanoma in particular, the HNK-1 glycotope has been positively correlated with poor prognosis. So far, no such correlation has been investigated in cutaneous melanoma. In order to do so, HNK-1 expression was evaluated immunohistochemically in 100 primary cutaneous melanomas and correlated with metastasis after up to 10-years' follow-up. Furthermore, HNK-1 expression was analysed in metastatic deposits (19 distant cutaneous metastases and six sentinel lymph node metastases), as well as in benign nevi. Kaplan-Meier analysis revealed a positive association between HNK-1 expression and metastasis (p < 0.005) and multivariate Cox regression analysis adjusted for the standard prognostic markers ulceration and vertical tumour thickness confirmed HNK-1 expression as an independent prognostic marker. HNK-1 expression was preserved in 42% of the distant cutaneous metastases, but metastatic cells in lymph nodes were devoid of HNK-1 immunoreactivity. None of the benign pigmented lesions exhibited HNK-1 immunoreactivity. Expression of the HNK-1 glycotope in cutaneous malignant melanoma is an independent prognostic marker of metastasis. Differential HNK-1 expression at the metastatic sites implies that its expression is modulated by the surrounding environment. As HNK-1 is also transiently expressed during migration of melanocyte precursor cells derived from the neural crest, recapitulation of this transient expression might occur during metastatic spread of cutaneous malignant melanoma.  相似文献   
83.
Chondroitin sulfate dipalmitoylphosphatidylethanolamine (CS-PE), when immobilized onto substratum, inhibited the adhesion of B16F10 mouse melanoma cells to fibronectin-coated dishes (anti-adhesion activity). CS-PE showed the most potent anti-adhesion activity for the melanoma cells among various GAG-PEs. CS-PE also inhibited the adhesion of B16F10 cells to Matrigel and the invasion of the cells into Matrigel. In the in vivo system of experimental metastasis, administration of B16F10 cells with CS-PE into C57BL/6 mice significantly inhibited lung metastasis. The inhibition degree of CS or hyaluronic acid-PE was lower than CS-PE. CS-PE administered intravenously into mice before the injection of B16F10 cells also inhibited metastasis. Pretreatment of B16F10 cells with CS-PE caused some but a lower degree of inhibition. When CS-PE was injected intravenously into mice, more binding in the lung was found than when CS was injected. CS-PE but not CS inhibited the retention in the lung of fluorochrome-labeled B16F10 cells when injected intravenously into mice. Since there was no significant effect of CS-PE on the viability and growth of B16F10 cells, the results suggest that CS-PE immobilized onto the subendothelial matrix may prevent melanoma cells from adhering to the subendothelial substrata of lung capillaries and inhibit subsequent invasion processes of metastasis.  相似文献   
84.
目的 观察重组卡介苗(rBCG)和中药猪苓多糖(PPS),对荷瘤小鼠空巨噬细胞释放NO的影响。方法 将黑色素瘤细胞株B16接种于小鼠左大腿外侧皮下,建立荷瘤小鼠模型,分别用rBCG-IL-2,rBCG-IL-2 PPSPPS进行局部治疗。于给药后第1,2,3和5wk处死小鼠,用NO酶法测定小鼠腹腔巨噬细胞释放NO的水平,并观察不同实验组瘤体的变化。结果 rBCG-IL-2组小鼠腹腔巨噬细胞释放NO的水平最高。与对照组相比较,PPS组小鼠腹腔巨噬细胞释放NO的水平在第1wk与第2wk增高,第3wk起与对照组释放的NO水平没有差异。rBCG-IL-2组小鼠随给药时间的延长,皮下瘤体逐渐缩小。PPS组小鼠瘤体在给药后第1wk和第2wk生长缓慢,第3wk起瘤体生长速度明显增加。结论 rBCG-IL-2与PPS能提高小鼠腹腔巨噬细胞释放NO的水平,rBCG-IL-2能明显抑制肿瘤生长。  相似文献   
85.
86.
Summary The cytological diagnosis of malignant Lymphoma in serous effusions can be difficult because reactive lymphocytes may be morphologically indistinguishable from malignant cells in lymphocytic and other low grade Non-Hodgkin's lymphomas. As a result of the present study, diagnostic accuracy can be improved by means of B- and T-cell enumeration using an immunoalkaline-phosphatase method (IAP). 30 cytological specimens, including 28 pleural, 1 pericardial and 1 ascitic fluids, were studied with a panel of monoclonal anti B- and anti T-cell antibodies (PAN B, kappa, lambda, T1, T2, OKT4, T8). Reactive lymphocytic effusions were characterized by a predominance of T cells constituting 80% of all lymphocytes with an excess of helper/inducer cells (mean helper to suppressor ratio 3.0) and by a surface kappa to surface lambda ratio of 1.6 on B-cells. Tuberculous effusions showed a similar distribution of lymphocyte-subpopulations whilst most of the carcinomatous fluids showed a lower percentage of T cells (lowest value 67%) and lower Th:Ts ratio (mean 2.0). Lymphoid cells in samples of five B-cell lymphomas were characterized by T-cell depression ( 70%). B-cells in three cases expressed clear cut light chain monoclonality which was at least suggested in the other two cases.Lymphoid cells from two cases of Hodgkin's disease expressed an indistinct immunological pattern. Labelling of cytoplasmic immunoglobulins (heavy and light chains) using the peroxidase antiperoxidase method (PAP) may be important to characterize neoplasms of the plasma cell series.It is concluded that the chosen panel of antibodies in combination with IAP labelling method may be of great value in identifying B-cell lymphomas. The technique can be used in the routine laboratory and storage of unlabelled and labelled slides over long periods is possible.Dedicated to Professor K. Lennert, Kiel, on the occasion of his 65th birthdayThis study was supported by the Krebsliga St. Gallen/Appenzell  相似文献   
87.
Summary Although cryostat sections in general allow a distinction to be made between malignant melanomas and other pigmented lesions in clinically doubtful cases, the differential diagnosis may be difficult. The histological and cytological criteria taken into account can be classified as major, minor, and insufficient. Knowing the diagnostic value of each makes a conventionally established diagnosis safer. Variance analysis does not contribute to the problem but it can nevertheless be shown that the evaluation of six major criteria makes a quick and reliable cryostat section diagnosis possible. If these results are confirmed in a prospective study it would be a decisive step on the way to a quicker and safer cryostat section diagnosis of malignant melanoma, even for the less experienced histopathologist.The results published here were presented in part at the DDG meeting 1980 at Westerland/SyltWe are grateful to Miss Schubert, Institute of Biomathematics of the University of Munich, for the statistical evaluations  相似文献   
88.
Malignant fibrous histiocytoma: an ultrastructural perspective   总被引:1,自引:0,他引:1  
Malignant fibrous histiocytoma is a frequent diagnosis, but the relationship of the tumors to histologically similar soft tissue neoplasms is controversial. In this study, 157 examples representing the 4 main subtypes were reviewed by light microscopy and each tumor was studied with the electron microscope. Immunohistochemical stains were performed on 77 tumors. Electron micrographs on 100 fibrosarcomas were reviewed for comparison. Malignant fibrous histiocytomas often closely resemble fibrosarcomas at the ultrastructural level and differences between the two are generally of degree only. Evidence for true histiocytic differentiation was not found. The immunohistochemical results did not contradict the authors' impression from electron microscopy that malignant fibrous histiocytoma forms part of the histologic spectrum of tumors of fibroblasts.  相似文献   
89.
A 60-year-old Japanese woman was diagnosed at autopsy as having had hereditary hemorrhagic telangiectasia (HHT) associated with systemic hemangiomas. In her repoduction period, premenstrual epistaxis frequently occurred. At the age of 60, the patient died of malignant lymphoma. At autopsy, multiple telangiectatic spots were noted on the face, limbs and trunk. The paraaortic lymph nodes, which were enlarged and irregularly conglomerated, were histologically diagnosed as malignant lymphoma of the diffuse large cell type. Submucosal telangiectatic lesions were found in the gastrointestinal system from the oral cavity to the rectum. Cavernous hemangiomas were present in various visceral organs including the liver, spleen, small and large intestines, rectum, appendix, uterus, and jejunal and colonic mesenteries. There was an arteriovenous fistula in the left lung. Examination of her family pedigree showed that the patient had an autosomal dominant trait of inheritance. The pathogenesis of the systemic visceral hemangiomas observed in this patient was considered to be similar to that of hamartoma.  相似文献   
90.
Molecular determinants of human uveal melanoma invasion and metastasis   总被引:19,自引:0,他引:19  
The molecular analysis of cancer has benefited tremendously from the sequencing of the human genome integrated with the science of bioinformatics. Microarray analysis technology has the potential to classify tumors based on the differential expression of genes. In the current study, a collaborative, multidisciplinary approach was utilized to study the molecular determinants of human uveal melanoma invasion and metastasis. Uveal melanoma is considered the most common primary intraocular cancer in adults, resulting in the death of approximately 50% of patients affected. Unfortunately, at the time of diagnosis, many patients already harbor microscopic metastases, thus underscoring a critical need to identify prognostic markers indicative of metastatic potential. The investigative strategy consisted of isolating highly invasive vs. poorly invasive uveal melanoma cells from a heterogeneous tumor derived from cells that had metastasized from the eye to the liver. The heterogeneous tissue explant MUM-2 led to the derivation of two clonal cell lines: MUM-2B and MUM-2C. Further morphological and functional analyses revealed that the MUM-2B cells were epithelioid, interconverted (expressing mesenchymal and epithelial phenotypes) highly invasive, and demonstrated vasculogenic mimicry. The MUM-2C cells were spindle-like, expressed only a vimentin mesenchymal phenotype, poorly invasive, and were incapable of vasculogenic mimicry. The molecular analysis of the MUM-2B vs. the MUM-2C clones resulted in the differential expression of 210 known genes. Overall, the molecular signature of the MUM-2B cells resembled that of multiple phenotypes – similar to a pluripotent, embryonic-like genotype. Validation of select genes that were upregulated and down-regulated was conducted by semiquantitative RT-PCR measurement. This study provides a molecular profile that will hopefully lead to the development of new molecular targets for therapeutic intervention and possible diagnostic markers to predict the clinical outcome of patients with uveal melanoma. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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