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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A primary leiomyosarcoma of skin was studied by light and electron microscopy and by histochemistry. Systematic evaluation of the entire neoplasm suggested that a single biopsy sample would show little cellular pleomorphism but could vary considerably in number of mitoses per mm2. Electron microscopy revealed a high degree of cytologic differentiation. Strong myosin ATPase activity and negative demonstrations for hydrolytic enzymes suggest a diagnostic profile which will clearly separate this neoplasm from malignant fibrous histiocytoma. High mitoses counts, the conventional criterion for malignancy of non-cutaneous smooth muscle tumors, may not be appropriately applied to primary leiomyosarcomas arising in the dermis. The findings in this case and a critical review of the literature suggest that reliable criteria for diagnosis of primary cutaneous leiomyosarcoma by light microscopy remain to be established.
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PMID:Primary leiomyosarcoma of skin: a report and critical appraisal. 15 62

Osteosarcoma of bone is a tumor composed of malignant cells that produce osteoid. Some tumors show predominant chondroid or fibromatoid ground substance. All, however, are highly malignant and about 80 per cent produce death with metastases. The roentgenogram affords important evidence for the correct diagnosis of many of them. Differential diagnosis should include consideration of those sarcomas with many benign giant cells and the group of "telangiectatic" osteosarcomas that may contain only small diagnostic areas. Malignant fibrous histiocytoma is now considered as a possible diagnosis for some malignant bone tumors, but the exact criteria for the diagnosis of this condition are still somewhat obscure. Newer modalities of adjunctive treatment, such as resection of pulmonary metastases, chemotherapy, and immunotherapy, give promise of improving the prognosis for osteosarcoma.
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PMID:Pathology of osteosarcoma. 16 99

Avid 67Ga-citrate uptake was observed in a malignant fibrous histiocytoma of the mediastinum. The realtionships of the tumor to the heart and liver was shown by 99mTc-sulfur colloid liver-spleen scanning and 99mTc-pertechnetate angiography performed in conjunction with a 67Ga-citrate whole-body scan. This is the first report of 67Ga-citrate uptake by this unusual tumor.
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PMID:Gallium-67 uptake by a malignant fibrous histiocytoma: case report. 17 41

An autopsy case of radiation-induced intracranial malignant fibrous histiocytoma (fibroxanthosarcoma) is reported. The tumor developed in the region of the sella turcica 11 years after high dose radiotherapy of a chromophobe adenoma of the pituitary. The tumor had infiltrated the base of the brain as well as the base of the skull. Metastases were not found. The tumor was composed of an admixture of bizarre fibroblasts, histiocytes and giant cells, xanthoma cells and siderophages, with a storiform fibrous stroma. This appears to be the first documented instance of a malignant fibrous histiocytoma occurring intracranially after local x-irradiation.
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PMID:Radiation-induced intracranial malignant fibrous histiocytoma. 18 Nov 26

A caisson worker with symmetrical bone infarcts in the tibiae demonstrated a malignant transformation of one of the bone infarcts with wide-spread metastases to the lungs and viscera. Histologically, the tumor was found to be a malignant fibrous histiocytoma and despite amputation, the patient died approximately one year following the diagnosis. This case lends credence to the concept of a cause and effect relationship existing between bone infarcts and the subsequent development of bone sarcoma.
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PMID:Malignant fibrous histiocytoma associated with bone infarcts: report of a case. 18 26

Existence of an entity called malignant fibrous histiocytoma of bone was emphasized, based on two of our own cases experienced recently and on previous reports related to this tumor. Histologically the tumor resembles markedly the malignant fibrous histiocytoma originating in the soft part. In addition, an attempt was made to clarify its biological behavior, histological subclassification and criteria to be malignant and differential diagnoses from several other bone diseases which sometimes mimic this malignant bone tumor.
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PMID:Malignant fibrous histiocytoma of bone. 18 59

It has been generally recognized that malignant fibrous histiocytoma (MFH) may assume a highly myxoid, hypocellular appearance. Eighty cases of malignant fibrous histiocytoma having varying degrees of myxoid change were reviewed. These tumors typically arose on the extremities (leg, 61%; arm, 21%) of adults (peak age incidence, 60-69 years). They were usually attached to fascia (31%) or involved skeletal muscle (51%) and had a mucoid or translucent appearance. The myxoid areas consisted of widely spaced spindled and pleomorphic cells embedded in a matrix of acid mucopolysaccharides. The cellular areas were indistinguishable from those of the typical pleomorphic MFH. The rate of local recurrence of these tumors was 61%, and of metastasis, 23%, but metastasis was less likely when the tumor was small, superficially located, or had a prominent myxoid component. In fact, the degree of myxoid change was inversely related to the rate of metastasis. Therefore, because of the more favorable prognosis of the myxoid variant, it seems appropriate to separate it from the usual nonmyxoid form of MFH. The myxoid variant must also be clearly distinguished from benign myxoid lesions such as myxoma or nodular fasciitis, with which it is often confused.
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PMID:Myxoid variant of malignant fibrous histiocytoma. 19 34

Myofibroblasts were detected by electron microscopy in five of five cases of fibrosarcoma and in five of six cases of malignant fibrous histiocytoma. In some areas myofibroblasts constituted up to 75 per cent of the tumor cells. Most myofibroblasts contained only sheaves of myofilaments along the margins of the cells, but some cells contained larger bundles of myofilaments and very closely resembled smooth muscle cells. An additional related type of cell was seen in several cases; it was large and possessed abundant eosinophilic cytoplasm, resembling a rhabdomyoblast at the light microscopic level. By electron microscopy this type of cell was seen to contain plentiful rough endoplasmic reticulum and large aggregates of fine filaments with rare dense bodies. These findings suggest that fibrosarcomas and malignant fibrous histiocytomas contain cells showing a spectrum of differentiation from fibrocytic to myogenic and that at the ultrastructural level the distinction between fibroblast and smooth muscle tumors may be blurred.
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PMID:Myofibroblasts and related cells in malignant fibrous and fibrohistiocytic tumors. 19 57

Four cases of malignant giant cell tumor of soft parts (MGCT) were studied ultrastructurally. Most of the cells in three cases were identified as undifferentiated mesenchymal cells and mononuclear monohistiocytic cells. The osteoclastlike cells seemed to arise from fusion of monohistiocytic cells. Immature fibroblastic cells, occasionally containing filaments with densities, were also present. They were scarce in three cases and predominant in the fourth. It was concluded that MGCT is a mesenchymal sarcoma with a bimorphic--monohistiocytic and fibroblastic--differentiation. MGCT is therefore considered a special variant of malignant fibrous histiocytoma.
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PMID:Malignant giant cell tumor of soft parts. An ultrastructural study of four cases. 19 4

Sixteen cases of malignant fibrous histiocytoma are presented. Electron microscopy of 15 cases demonstrated fibroblast-like and mononuclear and multinucleated histiocyte-like cells. A small capillary was at the center of all storiform areas examined. Ultrastructural examination can be diagnostically useful within the context of a narrow differential diagnosis by conventional microscopy and the ability, by electron microscopy, to eliminate other mesenchymal cell types. In 13 cases, follow-up information was available from 18 months to 9 years following histological diagnosis. Five patients are alive and 8 patients have died, including two non-tumor related deaths. In 3 cases follow-up was less than 4 months. The biologic behavior of the tumor in this series was generally not related to histopathological parameters. The issue of histogenesis is largely unresolvable. Ultrastructural studies of various types of fibrous histiocytomas, suggesting cells of origin other than histiocytes, give credence to the concept that the histiocyte may represent a morphologic state of a given mesenchymal cell rather than a particular cell type.
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PMID:Malignant fibrous histiocytoma. An electron microscopic study. 19 5


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