1/29. Primary giant cell malignant fibrous histocytoma of the lung: a case report.A rare case of malignant fibrous histiocytoma of giant cell type originating in the lung of a 46-year-old woman is presented. The patient complained of having a cough that had lasted for a few weeks. A chest X-ray photograph showed a tumor shadow on the left lung. Histological and cytological examination of the biopsy specimen revealed that the tumor was a kind of sarcoma. An operative procedure was selected because of tumor invasion into the trunk of the left pulmonary artery, which was discovered on computed tomography examination, and because metastatic tumor was excluded clinically. The tumor was almost encapsulated and 6 x 6 x 6 cm in size; however, it also showed invasion into the pulmonary artery and bronchial lumen. A histological survey of the tumor showed a wide range of patterns such as fibrous, pleomorphic, fascicular and osteoclast-like giant cell figures; however, the osteoclast-like giant cell area was predominant. Immunohistochemically, the tumor cells were positive for vimentin, CD68 for histiocytic marker and alpha1-antichymotrypsin, and negative for keratin, epithelial membrane antigen, S-100 protein, MT-1, desmin, myoglobin and lysosome. No primary tumor was found clinically in any part of the patient's body at 2 and 4 months after operation. Consequently, she was diagnosed as having primary giant cell malignant fibrous histiocytoma of the lung.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
2/29. Multinucleate cell angiohistiocytoma: report of two cases with no evidence of human herpesvirus-8 infection.Multinucleate cell angiohistiocytoma (MCA) is a vascular tumor of unknown pathogenesis. Possible misinterpretation of this disorder with Kaposi's sarcoma (KS), a human herpesvirus-8 (HHV-8)-associated tumor, prompted us to look for this virus in two women with MCA. None of the multiple skin specimens obtained from both our patients produced amplified HHV-8 dna. Using a cell culture methodology similar to that used for KS, we established cell cultures from MCA lesions. While KS spindle cells are known to exhibit in vitro invasive properties and can be grown up to more than 20 passages, the MCA-derived cells were short-lived and were not able to traverse basement membranes. Taken together, our data support the hypothesis that MCA is not a neoplasm but a benign vascular proliferation which is clearly distinguishable from KS.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
3/29. Myxoid malignant fibrous histiocytoma of the uterus: a case with immunohistochemical, ultrastructural and tumor cell culture studies.The clinical and pathological features, including ultrastructural and immunohistochemical findings, of a primary myxoid malignant fibrous histiocytoma of the uterus in a 60-year-old woman are reported. Microscopically, the principal feature of the tumor was a hypocellular area with diffuse degeneration, containing thin-walled curvilinear vessels, in which hyperchromatic small spindle and stellate cells, sometimes with vacuolated cytoplasm, were found. The transplanted tumor of primary cultured cells in nude mice presented as a prominent myxoid stroma confirming the histological structure of the primary tumor. Immunohistochemically, the presence of epithelial or heterogenous mesenchymal tumor components or cells of smooth muscle derivation were excluded and the tumor cells were positive for vimentin, CD 68, alpha 1-antitrypsin and alpha 1-antichymotrypsin. Ultrastracturally, pseudopodia and filopodia at the cell membrane and intracytoplasmic lysosomal granules were common. The patient had debulking surgery but died 38 days after the primary onset with the tumor occupying the entire abdomen and the pelvis.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
4/29. Cystic malignant fibrous histiocytoma of the gastrocolic ligament.A case of malignant fibrous histiocytoma (MFH) of the gastrocolic ligament is presented. It appeared as a huge, thin walled cystic tumour in the upper abdominal cavity on CT. barium studies showed splaying of the stomach and transverse colon by the mass. 1 year after resection of the cystic tumour, recurrence occurred at the greater curvature of the stomach and in the liver, with a cystic appearance similar to the primary tumour. To our knowledge, the CT appearance of primary cystic MFH of the gastrocolic ligament has not been previously documented.- - - - - - - - - - ranking = 73.034933938315keywords = ligament (Clic here for more details about this article) |
5/29. Malignant fibrous histiocytoma of the vagina.We describe here the case of an 82-year-old woman presenting with a hemorrhagic tumor on the anterior vaginal wall. She was diagnosed with malignant fibrous histiocytoma (MFH) from the findings of cytological analysis of biopsied surface tissue, histopathologic analysis of biopsied tissue, immunohistochemical staining, and electron microscopy. Cytological analysis of the biopsy sample harvested from the tumor surface showed multinucleated giant cells and large atypical cells with rough, granular, chromatin, as well as notable nucleoli. A storiform pattern was observed histopathologically, and immunohistochemical staining confirmed positive reactions to alpha 1-antichymotripsin (alpha 1-ACT), vimentin, and lysosome, but negative reactions to epithelial membrane antigen (EMA), cytokeratin, and alpha-smooth muscle action (alpha-SMA). Electron microscopy showed histiocyte-derived cells with a segmented nucleus with a large groove, pseudopodic cytoplasmic projections, and lysosome-like structures. However, intercellular adhesion factors were not notable, and microvilli were absent. Based on the above findings, a diagnosis of MFH originating from the vaginal wall was made. Because of the patient's advanced age, and, in accordance with her wishes, three courses of cancer chemotherapy, consisting of doxorubicin hydrochloride, fluorouracil, and cisplatin were carried out, without surgery. No reduction in the size of the tumor was seen at follow up, and despite the absence of metastasis and no exacerbation of her general condition, she died suddenly at home 2 years after being discharged.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
6/29. CD34-reactive myxoid dermal dendrocytoma.Normal skin is composed in part of cells that express CD34. These include periadnexal spindle cells, vascular endothelial cells, and interstitial dendritic cells. We report on a tumor composed mainly of CD34-reactive spindle cells. A 66-year-old Japanese woman presented with a skin-colored, dome-shaped, cutaneous papule on her left palm that was 7 mm in diameter and had developed within the preceding 3 months. light microscopic examination showed a well-circumscribed polypoid tumor consisting of spindle-shaped cells and thin collagen fibers arranged loosely in a fascicular pattern within a myxoid matrix. Immunohistochemically, most of the tumor cells stained strongly for CD34, but did not stain with antibodies to S-100 protein, smooth muscle actin, desmin, neuron-specific enolase, epithelial membrane antigen, or factor xiiia. Staining for vimentin and CD68 was positive. We believe this lesion to be a CD34-reactive myxoid dermal dendrocytoma of a type that has not been described previously.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
7/29. Decreased CD44 expression and stromal hyaluronate accumulation in myxoid dermatofibroma.BACKGROUND: Dermatofibroma (DF) is a common benign histiocytic tumor, which has several clinicopathological variants. Myxoid DF is one of these variants, which is characterized by a stromal mucin deposition. CD44 is a polymorphic transmembrane glycoprotein and the principal cell surface receptor of hyaluronate (HA), the major component of the extracellular matrix. In a recent study, we have observed an abnormal accumulation of HA in the superficial dermis of transgenic mice with a keratinocyte-specific CD44 expression defect. We have also shown that HA was accumulated in large amounts in the superficial dermis of lichen sclerosus et atrophicus (LSA) lesions and that the epidermal CD44 expression of LSA skin was significantly decreased or lost. In an another study, we have suggested that a decrease in CD44 expression in follicular epithelial proliferations might be correlated with an abnormal HA accumulation in perifollicular solitary cutaneous myxoma. Recently we have also demonstrated that classical DF lesions displayed a strong CD44 expression in tumor cells and a weak HA positivity in tumor stroma whereas CD44 expression was significantly reduced or absent in dermatofibrosarcoma lesions and the tumor stroma showed strong HA staining. OBJECTIVE AND methods: Here we present 3 cases of myxoid DF, in which we explored the nature of the mucinous material in myxoid stroma by colloidal iron and hyaluronic acid binding protein stainings, as well as the expression of CD44 in the tumor cells by immunohistochemistry. RESULTS: We show that HA is accumulated in the stroma of all myxoid DF lesions with a significant decrease in CD44 expression in the tumor cells. CONCLUSION: Our results suggest that a decrease in CD44 expression in the tumor cells may result in stromal myxoid changes characterized by an abnormal HA accumulation in myxoid DF.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
8/29. Benign fibrous histiocytoma of the renal capsule.The first case of benign fibrous histiocytoma of the renal capsule is reported in a male aged 44 years. The tumor had its point of origin in the renal capsule. Histologically, the tumor was composed of intersecting fascicles of fibroblastic cells forming a loose crisscross or "storiform" pattern. Electron microscopic studies of tumor cells revealed intermediate filaments and membrane-bound collagen fibers which continued to extracellular collagen bundles. This deep seated fibrous histiocytoma had a more prominent storiform pattern and fewer secondary elements such as xanthoma cells than cutaneous ones.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
9/29. Sclerosing meningioma: clinicopathological study of four cases.Sclerosing meningioma is a distinct histologic subtype of meningioma, however, it is often confused with other tumors, especially malignant tumors. To widen our knowledge of sclerosing meningioma and to help neurosurgeons and neuropathologists diagnose this clinically and pathologically unfamiliar disease entity, we reviewed four such cases, which were originally misdiagnosed. Sclerosing meningiomas were assessed for cellularity, cellular pleomorphism, mitotic activity, brain invasion, and necrosis. Immunohistochemical staining was performed on paraffin-embedded sections using the avidin-biotin-peroxidase complex method. The histologic appearance of the underlying cerebral parenchyma invasion by tumor cells led to a diagnosis of malignant meningioma or to the completely erroneous diagnosis of ganglioglioma. The most conspicuous histologic finding of these four sclerosing meningiomas was extensive collagen deposition, so called 'sclerosis' and an intermingled small population of spindle or round cells with clear cytoplasmic halos, giving a 'fried egg' appearance. However, a typical meningothelial whorl pattern was identified in all cases. Tumor cells exhibited positive immunoreactivity for epithelial membrane antigen and vimentin, but were negative for glial fibrillary acidic protein, p53, S-100, and neuronal markers. Proliferative indices, using Ki-67, ranged from 0% to 4%, and brain invasion was present in three of four tumors. All four patients are doing well with no evidence of tumor recurrence (follow-up duration of 25 months to 12 years). Brain invasion needs to be re-evaluated as a criterion of malignancy in meningioma. Special attention should be paid to the diagnosis of this subtype of meningioma to prevent unnecessary postoperative radiotherapy and to ensure correct therapeutic decision.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
10/29. Paraneoplastic opsoclonus-myoclonus syndrome associated with malignant fibrous histiocytoma: neuropathological findings.paraneoplastic syndromes related to soft tissue tumors are very uncommon and an association of paraneoplastic diseases with a malignant fibrous histiocytoma (MFH) has not been reported so far. Opsoclonus-myoclonus is a rare paraneoplastic nervous system syndrome, that was well documented in adult patients with neoplasms particularly of the lung and breast. A 77-year-old woman developed typical opsoclonus-myoclonus syndrome and rapidly progressed to coma. The opsoclonus and generalized myoclonus continued until the patient's death seven months later. An autopsy examination identified a pleomorphic MFH in the retroperitoneum without a metastatic spread. Microscopic examination of the cerebellum revealed an atrophy of the granular layer along with a marked patchy loss of purkinje cells, and a loss of neurons in the cerebellar nuclei accompanied by distinct peridental demyelination and astrogliosis. A moderate loss of neurons and neuronal chromatolysis were observed also in the inferior olivary nuclei. However, the omnipause neurons of the nucleus raphe interpositus, that are supposed to be responsible for opsoclonus generation under pathological conditions, as well as ocular brain stem nuclei were all intact. We failed to prove the presence of known antineuronal anti-Yo, anti-Hu or anti-Ri autoantibodies in both serum and cerebrospinal fluid (CSF) of the patient. However, the confirmation of the intrathecal IgG synthesis by oligoclonal bands in CSF and the immunohistochemical detection of IgG deposits on membranes of purkinje cells, neurons of cerebellar granular layer and in cerebellar nuclei in our case support the presumed autoimmune nature of the disease.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
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