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1.
We review the spectrum of cutaneous disorders associated with inflammatory and neoplastic plasmacytic pathology. Because plasma cells are derived from B‐lymphocytes our overview includes discussion of certain lymphoplasmacytic proliferations. It is structured along histopathological lines, addressing conditions characterized by (a) cutaneous plasma cell infiltrates, (b) deposits of plasma cell products or their derivatives in the skin and (c) miscellaneous, poorly understood cutaneous complications of plasmacytic disorders. Lesions arising primarily in the skin and those due to cutaneous involvement by multisystem disorders are addressed. The range includes a spectrum of tumefactive and circulatory manifestations. We highlight key clinical and pathological features of the different conditions and outline recent advances in our understanding of these entities. By emphasizing the dermatopathological characteristics of this spectrum of disorders we hope to hone the diagnostic accuracy of practitioners in the field.  相似文献   
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Carcinosarcomas are biphasic tumors composed of admixed malignant epithelial and mesenchymal components. Numerous terms have been used to name such neoplasms; therefore, terminological confusion is frequent. Most examples of carcinosarcomas are encountered in non‐cutaneous sites, with approximately 100 cases of cutaneous carcinosarcomas reported so far in the English literature. Although different theories have been suggested to explain the occurrence of these peculiar neoplasms, histogenetic mechanisms should be better hypothesized depending on each individual case. Even though prognosis tends to be related to the specific components of the lesion, especially the epithelial one, it seems that cases of cutaneous localization usually have a better outcome. We report an exceedingly rare case of syringocystadenocarcinoma papilliferum which showed an atypical stroma with sarcomatoid appearance, and highlight that the terminology used for this spectrum of lesions is disorganized and confusing.  相似文献   
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Cutaneous plasmacytosis is a rare disorder characterized by a benign proliferation of mature plasma cells that appears as multiple dark-brown to purplish skin lesions, often associated with polyclonal hypergammaglobulinaemia. We present the case of a 55-year-old Caucasian man who suffered from a cutaneous plasmacytosis associated with two different carcinomas. Cutaneous plasmacytosis seems to be a reactive process because most cases reported are not associated with any apparent underlying disease. Nevertheless, because few reported cases were associated with malignancies, screening of additional neoplasms would be justified.  相似文献   
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Glomeruloid haemangioma is considered a specific marker of POEMS ( p olyneuropathy, o rganomegaly, e ndocrinopathy, M -protein and s kin changes) syndrome and it is usually but not always associated with multicentric Castleman's disease. We report a 78-year-old man who presented with a single, red-violet soft nodule with superficial telangiectases on the scalp. Histopathologically, the lesion consisted of lobules of coiled aggregated capillaries that involved the lumina of dilated vascular structures, mimicking renal glomeruli. A collagenous stroma separated the capillary lobules, and eosinophilic, periodic-acid–Schiff positive globules of varying sizes and shapes were seen within the cytoplasm of endothelial cells. Immunohistochemical studies with antibodies against IgA and IgG, and against the kappa and lambda light chains of immunoglobulins showed immunoreactivity within the eosinophilic globules. Results of complete blood count, liver, renal and thyroid function tests, fasting blood sugar measurement, serum levels of oestradiol, testosterone, prolactin and cortisol, serum protein electrophoresis, immunoelectrophoresis and immunofixation yielded normal or negative results. No Bence–Jones proteinuria was found in a sample from a 24-h urine collection. To our knowledge, only two cases of glomeruloid haemangioma have been previously reported in patients without POEMS syndrome. We describe the third case of glomeruloid haemangioma in a patient without features of POEMS syndrome.  相似文献   
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The aim of this study was to evaluate the cerebral synthesis of eicosanoids in the asphyctic newborn and to investigate the relation between the prostanoid profiles in cerebrospinal fluid (CSF) and the appearance and severity of hypoxic-ischaemic encephalopathy (HIE). Levels of 6-keto-PGF 1-α, TXB2, PGE2 and PGF2-α in CSF were measured in 40 full term newborns during the first day of life. Thirty of these newborns had birth asphyxia and were divided into three groups: 10 without HIE, 12 with mild HIE and 8 with moderate-severe HIE. They were compared to a control group of 10 non-hypoxic newborns. Determinations of the metabolites in CSF were performed by RIA and expressed as pg/ml (mean ± SD). The CSF TXB2 (thromboxane A2 metabolite) in asphyxiated newborns was always higher than in the control group (28.12 ± 10.6), and related to the severity of HIE ( p = 0:005): without HIE (50.84 ± 16.4; p = 0:02), mild HIE (80.65 ± 12.64; p ± 0:01) and moderate-severe HIE (178.14 ± 20.5; p < 0:01). The CSF 6-keto-PGF 1-α (prostacyclin metabolite) in asphyxiated newborns was always higher than in the control group (80.55 ± 12.56), but indirectly related to the severity of HIE: without HIE (240.95 ± 28.12; p < 0:01), mild HIE (183.65 ± 30.1; p < 0:01) and moderate-severe HIE (140.55 ± 25.12; p < 0:01). In the moderate-severe HIE group, the increase in TXB2 was higher than the rise in 6-keto-PGF 1-α.  相似文献   
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Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma   总被引:9,自引:3,他引:6  
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study.  相似文献   
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