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121.
The spectrum of clinical and histopathologic features associated with chronic graft-versus-host disease (GVHD) is broad, with recognized variants simulating scleroderma, lichen sclerosus, eosinophilic fasciitis, and de novo diffuse melanoderma. We report a case of a patient with multiple myeloma who presented approximately 1 year after his allogeneic hematopoietic stem cell transplantation with lesions of chronic lichenoid GVHD that harbored features of hypertrophic lupus erythematosus (LE) and that was initially mistaken for a superficial well-differentiated squamous cell carcinoma (SCC). However, in 4 years of follow-up, the patient failed to develop any evidence of cutaneous or systemic LE, actinic damage, or SCC, and the lesions cleared with topical and systemic treatments appropriate for chronic GVHD. For proper interpretation of the histologic findings of GVHD, it is important for the dermatopathologist to be aware of unusual manifestations. Knowledge of the occurrence of hypertrophic LE and familiarity with its histologic features is also important to avoid an erroneous diagnosis of SCC in immunosuppressed patients.  相似文献   
122.
Statin therapy may prevent an excessive inflammatory response after cardiopulmonary bypass for cardiac surgery. In a recent issue of Critical Care, Morgan and colleagues present data from a well-conducted systematic review and meta-analysis of randomised controlled trials using inflammatory markers as primary outcome measure. They find that pre-operative statin therapy, compared with placebo, may reduce various post-operative markers of systemic inflammation (IL-6, IL-8, C-reactive protein, tumour necrosis factor-alpha). Their ability to make definitive conclusions is limited, however, by the suboptimal methodological quality of the primary studies. Their review suggests that ICU researchers should focus on developing valid surrogate markers and use these to accurately describe the mechanisms and effectiveness of novel therapies before proceeding to large pragmatic trials using mortality as primary outcome.  相似文献   
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P J Allen  K Busam  A D Hill  A Stojadinovic  D G Coit 《Cancer》2001,92(6):1650-1655
BACKGROUND: Immunohistochemical analysis of sentinel lymph nodes from patients with breast carcinoma and melanoma has been shown to increase the sensitivity for detecting lymph node metastases. To the authors' knowledge, this technique has not been described in patients with Merkel cell carcinoma. METHODS: Lymphatic mapping and sentinel lymph node biopsy was performed on 26 patients with Merkel cell carcinoma between 1997 and 1999. All sentinel lymph nodes were analyzed with conventional hematoxylin and eosin (H&E) staining and then analyzed with immunohistochemical staining to evaluate whether this additional technique would increase the number of patients found to have lymph node metastasis. RESULTS: The median age of the patients in the current study was 67 years and the median tumor size at the time of presentation was 2 cm. Lymph node metastases were identified in 5 of the 26 patients (19%). Three of these five lymph node positive patients were identified with H&E staining. The remaining two patients were identified only after immunohistochemical analysis. The median follow-up in this group of lymph node positive patients was 14 months, with 2 of the 5 lymph node positive patients developing a recurrence. The median follow-up in the 21 patients who were lymph node negative was 19 months, with only 1 patient having developed a recurrence at the time of last follow-up. CONCLUSIONS: Immunohistochemical analysis of sentinel lymph nodes from patients with Merkel cell carcinoma appears to increase the sensitivity of detecting clinically occult lymph node metastases.  相似文献   
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The ultrastructural localization of an amorphous matrix to the interface between microvessel endothelium and tumor cells has been recently reported in a series of melanomas. Laminin expression as documented by immunohistochemistry was localized to microvessels in melanomas showing the amorphous matrix. In order to identify more precisely the type of laminin present in this amorphous material, immunostaining was carried out on cryostat sections from 16 human melanoma specimens. Four murine monoclonal antibodies directed against the alpha-3, beta-2, beta-3 and gamma-2 laminin chains were employed. In the melanomas studied, alpha3, beta3 and gamma2 laminin chains showed only minimal focal vascular positivity. In contrast, the beta2 (16/16 cases) laminin chain exhibited a consistent positivity in an angiocentric pattern about tumor microvessels. In all melanomas, some tumor cells seemed to spread along the abluminal surface of the small vessels, exhibiting a pericytic location, particularly along the intratumoral projections formed by the beta2 laminin chain. Given the role of laminin in migration and tumor progression, the results suggest a role of the beta2 laminin chain in melanoma spread, promoting tumor migration along the abluminal surface of vessel, a phenomenon which has been termed extra-vascular migratory metastasis.  相似文献   
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BACKGROUND: Near-infrared confocal scanning laser microscopy (CSLM) represents a novel imaging technique for in vivo microscopic analysis of skin lesions, including pigmented lesions. OBJECTIVES: To investigate the feasibility of detecting a clinically amelanotic malignant cutaneous melanoma using CSLM and to explore the use of this technique for assessing its margins. PATIENTS AND METHODS: Two lesions from 2 patients were imaged and analyzed using CSLM. Sites suspected to represent melanoma or benign skin on CSLM were marked as such; then, biopsy specimens were obtained for diagnosis using conventional histological analysis. Both lesions were stained for melanin pigment and analyzed immunohistochemically for the expression of melanosomal markers. In 1 case, a biopsy specimen was also examined with electron microscopy. RESULTS: The images obtained using CSLM allowed recognition of an abnormal intraepidermal melanocytic proliferation that was distinctly different from normal skin. Comparison of the sites examined using CSLM and subsequently using conventional histological methods revealed that CSLM correctly identified intraepidermal melanoma and benign skin. Fontana-Masson stains and immunohistochemical and ultrastructural studies showed that clinically amelanotic melanoma cells contained melanosomes and rare melanin granules. CONCLUSIONS: We demonstrated, for the first time, the detection of clinically amelanotic melanoma using CSLM. This technique may aid in the early detection of clinically barely visible or nonpigmented melanomas and may facilitate preoperative noninvasive assessment of their margins.  相似文献   
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