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41.
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Lymphoepithelioma-like carcinoma of the bladder is an uncommon neoplasm, of which 49 cases have been described in the English literature, none of which has been studied for p53 protein expression. We studied three muscle-infiltrating cases of this tumor using immunohistochemical, in situ hybridization and polymerase chain reaction (PCR) methods. The three cases were positive for epithelial markers and negative for lymphoid antigens in the tumoral syncytial areas. The intensive infiltrate of small cells was negative for epithelial and positive for lymphoid markers. This population was mainly made up of cytotoxic T-lymphocytes, positive for TIA-1. p53 protein was intensely positive in more than 90% of the epithelial component nuclei, being negative in the lymphoid cells. PCR study did not show mutations on p53. Both lymphocytes and epithelium were negative for Epstein–Barr virus markers, such as the latent membrane protein and EBER (Epstein–Barr-encoded RNA). The prognosis was very good after radiotherapy and chemotherapy treatment, preserving the bladder despite the muscle infiltration. The presence of an intense cytotoxic T-lymphocyte population may be related to this good prognosis. Both aspects, p53 protein status and T-lymphoid population, had never been studied before in bladder lymphoepithelioma-like carcinoma.  相似文献   
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A uterine leiomyosarcoma that became positive for HMB45 in the metastasis   总被引:1,自引:0,他引:1  
Uterine smooth muscle tumors are usually spindle cell lesions, but a minority is composed of epithelioid cells. Foci of clear cells can be found in these latter tumors. Recently, it has been shown that some of these tumors can be positive for HMB45, and some authors have advocated calling these lesions perivascular epithelioid cell (PEC) tumors or PEComas. The case we describe here clearly shows that the so called PEC is just a smooth muscle cell capable of changing its immunophenotype. The patient involved is a 29-year-old black woman who was found to have an epithelioid leiomyosarcoma of the uterus in November 1995. She was treated with a simple hysterectomy and bilateral salpingo-oophorectomy. A metastatic lesion was found in her liver. She, therefore, also received chemotherapy and was free of disease until October 2002, when a recurrent tumor was detected in her spine. After undergoing resection of the lesion at 2 different times, in 2002 and 2003, the patient was treated with radiotherapy and is currently receiving chemotherapy. On microscopic examination, the tumor in the uterus and liver both proved to be an epithelioid leiomyosarcomas that was diffusely positive for smooth muscle actin. Approximately 15% of the cells had clear cytoplasm, but sections from 2 different blocks were completely negative for HMB45. However, although the tumors resected from the spine in 2002 and 2003 showed features similar to those of the uterine neoplasm, but with a lower percentage of cells positive for smooth muscle actin and more clear cells, several of the clear cells were positive for HMB45. To the best of our knowledge, this is the first case of a uterine smooth muscle cell tumor that became positive for HMB45 when it metastasized.  相似文献   
45.
A Western blot to detect anti-HSP70 autoantibodies has been reported to be of diagnostic value for immune-mediated hearing loss patients. While setting up this Western blot in our lab, we detected two main problems. First, some patients were positive for antibodies to a 70-kDa protein when tested against a whole cell lysate, but negative if the antigen used was purified HSP70. Second, if high amounts of purified HSP70 were loaded on the gel, both patients and healthy controls were positive. We have developed and optimized an ELISA as an alternative to the Western blot. This assay is more appropriate to identify positive and negative individuals because it is semi-quantitative. The ELISA is also more sensitive, requiring very low concentrations of the antigen and thus minimizing false positives. Finally, we demonstrated that immune-mediated hearing loss patients recognize mainly the native form of HSP70, a fact that potentially leads to false negatives when a denaturing Western blot assay is used for diagnosis. To test the diagnostic value of the ELISA, we performed a blind test with 70 hearing loss patients, as well as 30 healthy controls. A sensitivity of 84% and a specificity of 93% were obtained, superior to what has been reported so far for the Western blot.  相似文献   
46.
Marchevsky AM  Wick MR 《Human pathology》2004,35(10):1179-1188
Recent advances in molecular pathology and other technologies such as proteomics present pathologists with the challenge of integrating the new information generated with high-throughput methods with current diagnostic models based mostly on histopathology and clinicopathologic correlations. Parallel developments in the field of medical informatics and bioinformatics provide the technical and mathematical methods to approach these problems in a rational manner. However, it remains unclear whether pathologists or other medical specialists will become primarily responsible for the development and maintenance of these multivariate and multidisciplinary diagnostic and prognostic models that are hoped to provide more accurate, individualized patient-based information. Evidence-based medicine (EBM) and medical decision analysis (MDA) are relatively new disciplines that use quantitative methods to assess the value of information, differentiate fact from myth, and integrate so-called best evidence into multivariate models for the assessment of prognosis, response to therapy, selection of laboratory tests, and other complex problems that influence individual patient care. We review from an epistemological viewpoint the current approach to information in pathology and describe some of the concepts developed by the practitioners of EBM and MDA.  相似文献   
47.
Chromophobe renal cell carcinoma with sarcomatoid transformation   总被引:2,自引:0,他引:2  
We present a rare case of a chromophobe renal cell carcinoma that progressed to a high-grade spindle cell sarcoma. The tumor affected a 50-year-old man who had presented with right upper quadrant discomfort and hematuria and subsequently underwent a right radical nephrectomy. Microscopically, the tumor was composed of two distinct components, a chromophobe renal cell carcinoma and a sarcomatoid component. The sarcomatoid component had exhibited aggressive behavior by spreading to a regional lymph node. This case report shows that chromophobe carcinoma can develop a sarcomatoid transformation with a high propensity for invasive growth and metastasis.  相似文献   
48.
 Three further cases of mature benign cystic teratomas of the ovary associated with virilization are added to the three previously reported in the literature. They were found in postmenopausal, obese, diabetic women aged 52, 61, and 67 years. The patients presented with hirsutism and voice changes and clitoromegaly was present in one. Testosterone and androstenedione levels were elevated but promptly regressed after removal of the tumours. Histologically, sheets of stromal luteinized cells were found peripherally at the interface between the neoplasm and ovarian tissue. Luteinization of ovarian stroma induced by an unknown factor related to diabetes mellitus is the origin of the virilization. Received: 8 January 1997 / Accepted: 28 February 1997  相似文献   
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We report ribosome-lamella complexes (RLC) in cancer cells of transitional cell carcinoma (TCC) of the prostate in a 52-year-old Caucasian man. Histopathologically, cancer cells were proliferated in various-sized nests, mostly associated with central necrosis. Some invaded into the surrounding normal glandular space and the stroma, with occasional lymphatic invasion. Fine structural study of cancer cells revealed that cross-sectioned RLC as well as densely aggregated ribosomes were detected in their cytoplasm, situated close to, but not directly connected with, dilated rough endoplasmic reticulum. These were composed of a concentric alternative arrangement of both lamellae and ribosomes. In the central and surrounding parts of the RLC, ribosomes were observed, revealing a smooth transition to the ribosomal component of RLC in size and shape. The presence of both RLC and dense aggregation of ribosomes close to the rough endoplasmic reticulum suggests that their functions might be related to specific or aberrant protein synthesis under unknown conditions. Although RLC have been often reported in hematopoietic malignancies, their occurrence in the malignant epithelial component has been only reported in a case of pulmonary adenocarcinoma. This is the first report of RLC in TCC in the literature.  相似文献   
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