Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019621 (Langerhans cell histiocytosis)
 3,250 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In this study fresh frozen tissue samples of benign osseous tumors (five non-osteogenic fibromas, one fibrous dysplasia, one chondromyxoidfibroma), tumors of uncertain biological behaviour (eight cases of histiocytosis X, two giant-cell tumors), and of malignant intraosseous tumors (two malignant fibrous histiocytomas, two malignant histiocytosis, four osteosarcomas, one chondrosarcoma and two Ewing sarcomas) were studied with a panel of monoclonal antibodies reactive with monocyte/macrophages and various types of dendritic cells. In addition, tumors were further defined with a broad spectrum of antibodies against filamentous proteins and lymphocyte differentiation antigens. The specimens were stained with a triple-layer immunoalkaline phosphatase protocol. Tumors stained with these antibodies could be roughly divided into two groups. The first group comprised tumors with one predominant cell population reactive with one particular monoclonal antibody. In this group, cases of histiocytosis X were found to be consistently labelled with CD-1 antibodies. The giant-cell tumors showed a very homogeneous staining with certain monocyte/macrophage antibodies (Ki-M8). Nevertheless, even in these tumors, heterogeneity was demonstrated by the occurrence of cells with monocytic differentiation in histiocytosis X and conversely by the occurrence of cells with differentiation antigens of the dendritic cell system in giant-cell tumors. An exception has to be made for the two cases of malignant histiocytosis examined. These tumors were selectively labelled with antibodies against monocyte/macrophages (Ki-M8, IOM-1). The second group comprised tumors showing a high degree of heterogeneity demonstrated by the varying amounts of tumor cells reacting with the applied markers of the monocyte/macrophage and dendritic cell systems. In most cases it was difficult to ascribe labelled cells to the tumor cell population as opposed to an "innocent bystander" inflammatory cell population. This distinction was especially difficult in malignant fibrous histiocytomas underlining the current concept that these tumors are of primitive mesenchymal rather than true histiocytic origin.
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PMID:Histiocytic differentiation in benign and malignant bone tumors. 246 63

Tumors of the pediatric facial skeleton represent a major challenge in clinical practice because they can lead to functional impairment, facial deformation, and long-term disfigurement. Their treatment often requires a multidisciplinary approach, and radiologists play a pivotal role in the diagnosis and management of these lesions. Although rare, pediatric tumors arising in the facial bones comprise a wide spectrum of benign and malignant lesions of osteogenic, fibrogenic, hematopoietic, neurogenic, or epithelial origin. The more common lesions include Langerhans cell histiocytosis and osteoma, while rare lesions include inflammatory myofibroblastic and desmoid tumors; juvenile ossifying fibroma; primary intraosseous lymphoma; Ewing sarcoma; and metastases to the facial bones from neuroblastoma, Ewing sarcoma, or retinoblastoma. This article provides a comprehensive approach for the evaluation of children with non-odontogenic tumors of the facial skeleton. Typical findings are discussed with emphasis on the added value of multimodality multiparametric imaging with computed tomography (CT), magnetic resonance imaging (MRI) with diffusion-weighted imaging (DWI), positron emission tomography CT (PET CT), and PET MRI. Key imaging findings and characteristic histologic features of benign and malignant lesions are reviewed and the respective role of each modality for pretherapeutic assessment and post-treatment follow-up. Pitfalls of image interpretation are addressed and how to avoid them.
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PMID:Non-odontogenic tumors of the facial bones in children and adolescents: role of multiparametric imaging. 2828 10