1/769. Paraneoplastic pemphigus associated with follicular dendritic cell sarcoma arising from Castleman's tumor.Paraneoplastic pemphigus (PNP) is associated with various forms of underlying neoplasia. We report a patient with PNP associated with an intraabdominal follicular dendritic cell sarcoma that developed from a Castleman's tumor that had preexisted for 40 years.- - - - - - - - - - ranking = 1keywords = cell (Clic here for more details about this article) |
2/769. Extranodal follicular dendritic cell sarcoma of the palate.Follicular dendritic cell tumors are uncommon and usually occur in lymph nodes. We report the case of a follicular dendritic cell tumor that occurred in the palate of a 14-year-old boy and manifested itself as a nodular mass. Histologically, the neoplasm consisted of spindle-shaped or oval-shaped cells with eosinophilic cytoplasms and nuclei with delicate, dispersed chromatin. The lesional cells were principally arranged in diffuse, fascicular patterns with vaguely whorled or storiform areas. Focal multinucleate tumor giant cells and lymphocytes were observed throughout the neoplasm. Immunohistochemically, tumor cells were positive for the follicular dendritic cell markers CD21, CD35, and CD23 and for S-100 protein, CD68, and muscle-specific actin. Tumor cells were negative for LCA, CD20, EMA, CK (AE1/AE3), HMB45, and CD34. lymphocytes were positive for LCA and CD45RO. Although follicular dendritic cell sarcoma is a very uncommon tumor, it should be included in the differential diagnosis of tumors in this location.- - - - - - - - - - ranking = 4.6409970201354keywords = spindle, cell (Clic here for more details about this article) |
3/769. Histochemical investigation into the molecular mechanisms of malignant transformation in a benign glomus tumour.A glomangiosarcoma arose in a benign glomus tumour. The histological and immunohistochemical characteristics of the tumour were investigated. Apoptotic cells were identified by terminal deoxynucleotidyl transferase (TdT) mediated dUTP-biotin nick end labelling (TUNEL). The proportion of apoptotic cells was found to be low and TUNEL positive nuclei were present in the benign part of the tumour. Bcl-2 protein, an inhibitor of apoptosis, was strongly expressed in the glomangiosarcoma with only weak staining in the benign area. The proliferation index of the glomangiosarcoma was almost 10-fold higher than that of the benign glomus tumour. Numerous nuclei in the glomangiosarcoma were intensely stained for the tumour suppressor protein p53. The results of the this study may contribute to an understanding of the molecular basis of malignant transformation in benign glomus tumours.- - - - - - - - - - ranking = 0.4keywords = cell (Clic here for more details about this article) |
4/769. Myxoid variant of follicular dendritic cell sarcoma arising in the breast.Follicular dendritic cell sarcoma is a malignant tumor of the follicular dendritic cell which can arise in extranodal sites. We present here a case arising as a mass in the breast of a 41-year-old woman. The tumor was composed of mildly pleomorphic spindly cells with pale ovoid nuclei and cell processes intimately admixed with mature lymphocytes. In much of the lesion the cells were dispersed in cords in a myxoid stroma, and elsewhere there were solid sheets. The neoplastic cells were immunoreactive for CD21, CD35, EMA, and S100 protein, but not for other lymphoid markers or cytokeratin. Electron microscopy showed interdigitating cytoplasmic processes with junctions but no external lamina. The differential diagnosis includes carcinoma, lymphomas, and a variety of myxoid sarcomas. The tumor recurred within a few months and displayed increased nuclear pleomorphism and lymphatic invasion but the patient appears free of disease 3 years after the further excision. This case extends the spectrum of follicular dendritic cell sarcoma in soft tissue sites.- - - - - - - - - - ranking = 2.2keywords = cell (Clic here for more details about this article) |
5/769. Low-grade fibromyxoid sarcoma: clinicopathologic case report with review of the literature.Low-grade fibromyxoid sarcoma is a rare, benign-appearing soft tissue neoplasm with an aggressive clinical course characterized by multiple local recurrences over several years, with ultimate spread to lung and occasionally to bone. Thus far, a total of 24 cases of low-grade fibromyxoid sarcoma have been reported in the literature. The authors present an additional case that grossly and microscopically emphasizes a pronounced lobular pattern of contrasting areas of cellularity showing high proliferative activity, as demonstrated by a proliferation marker, Ki 67 with MIB-1, and hypocellular areas with prominent myxoid component and abundant collagen fibrils. There was predominance of delicate capillary-sized stromal vessels with collagenized walls in both cellular and myxoid areas. The unusual features in this case were osseous metaplasia, prominent intranuclear pseudoinclusions, dna tetraploidy, and membrane-bound intracytoplasmic fat vacuoles. The immunoprofile and cytologic and ultrastructural features are described. After the excision of the tumor, the patient was treated with radiotherapy without chemotherapy. The patient has been observed for 26 months and is alive without the evidence of disease. The postoperative follow-up with axial computed tomography at 24 months showed no evidence of disease, except postsurgical fibrotic changes.- - - - - - - - - - ranking = 0.6keywords = cell (Clic here for more details about this article) |
6/769. Dendritic cell sarcoma of the thyroid.BACKGROUND: Follicular dendritic cell sarcoma (FDCS) arises from nonlymphatic antigen-presenting cells found in lymph node B-cell follicles. This extremely rare tumor, which usually arises in lymph nodes, does occur in extranodal head and neck sites such as the tonsil and soft palate. methods: A retrospective review of the patient followed at the University of Pittsburgh Medical Center from 1993 to the present was performed. CONCLUSIONS: This is the first reported case of an FDCS of the thyroid. A review of the literature provides useful information to aid in detection, treatment, and outcome of this unusual soft tissue malignancy.- - - - - - - - - - ranking = 1.4keywords = cell (Clic here for more details about this article) |
7/769. Proximal-type epithelioid sarcoma in the pelvic soft tissues.A case of proximal-type epithelioid sarcoma arising in the pelvic soft tissues of a 46-year-old man is presented. The tumor showed a predominantly epithelioid component with rhabdoid features, cord-like arrangement, small nests, abundant eosinophilic cytoplasm containing intracytoplasmic, paranuclear, hyaline-like globules, large vesicular nuclei, and prominent nucleoli. There were foci with alveolar arrangement and a spindle-cell proliferation. The tumor cells were positive for cytokeratin CAM5.2, vimentin, epithelial membrane antigen, and CD34. flow cytometry showed a diploid dna content with high S-phase fraction. The patient had pelvic lymph-node metastases. He died of the disease 5 months after diagnosis. It is important to include proximal-type epithelioid sarcoma in the differential diagnosis of pelvic tumors.- - - - - - - - - - ranking = 2.4409970201354keywords = spindle, cell (Clic here for more details about this article) |
8/769. Cellular schwannoma mimics a sarcoma: an example of a potential pitfall in aspiration cytodiagnosis.Cellular schwannoma, a variant of benign schwannoma, is characterized by marked nuclear pleomorphism and hyperchromasia and may be overdiagnosed as a malignancy in fine-needle aspiration specimens. We report the aspiration cytology findings of a case of cellular schwannoma that arose in the parapharyngeal region of a 50-yr-old woman.- - - - - - - - - - ranking = 0.2keywords = cell (Clic here for more details about this article) |
9/769. Intrahepatic cholangiocarcinoma with extensive sarcomatous change: report of a case.A 77-year-old woman was admitted to our hospital with severe upper abdominal pain. ultrasonography showed a well-defined hypoechoic mass with heterogeneity in the left lobe of the liver, and computed tomography demonstrated a low-density mass with enhanced peripheral areas. magnetic resonance imaging revealed a mass with iso- to low signal intensity on T1-weighted images (WI) and heterogeneous high and low signal intensity on T2 WI. The tumor was found to be hypovascular by angiography. During 5 months of observation, the tumor increased in size, which strongly suggested malignancy. A laparotomy was performed under the provisional diagnosis of a neoplasm other than hepatocellular carcinoma, revealing that the hepatic mass had invaded the gastric wall. Therefore, a left hepatic lobectomy with dissection of the lymph nodes and hemigastrectomy was carried out. Histologically, the tumor was found to be composed of a large amount of sarcomatous elements and a small amount of adenocarcinomatous elements, both of which were partly intermingled. Immunohistochemically, the sarcomatous element demonstrated the features of malignant fibrous histiocytoma (MFH). Thus, a diagnosis of intrahepatic cholangiocarcinoma with MFH-like sarcomatous change was confirmed.- - - - - - - - - - ranking = 0.2keywords = cell (Clic here for more details about this article) |
10/769. Epithelioid sarcoma of the penis. Clinicopathologic study of a tumor with myogenic features and review of the literature concerning this unusual location.Soft tissue tumors of the penis are uncommon. We report here the clinicopathologic features of a penile epithelioid sarcoma (ES), review the literature concerning this unusual location and focalize our attention on its differentiation. The 34-year-old patient was admitted for abrupt urinary retention due to the growth of a firm and painful plaque on the left side of the shaft, three years previously clinically diagnosed as Peyronie's disease. Magnetic nuclear resonance revealed an infiltrating lesion of both corpora cavernosa. histology of bioptic fragments showed a nodular malignant spindle and epithelioid cell tumor with focal necrosis and relatively high mitotic rate. Based on the immunohistochemical data (cytokeratin , vimentin , EMA , CD34 , and S100-), the diagnosis of ES was strongly considered. Penectomy was undertaken and the diagnosis confirmed by both light and ultrastructural microscopy. The 22 month follow-up was free of recurrences and metastases. Although not dissimilar from the 10 previously described ES of the penis in terms of natural history and histology, the tumor reported here showed myogenic features as revealed by both immunohistochemistry (immunoreactivity for muscle specific actin) and ultrastructure (intercellular junctions, discontinuous basal lamina, pinocytotic vesicles and thin filaments with intercalated dense bodies). Although previously observed in ES of other sites, this feature has never been established in ES of the penis.- - - - - - - - - - ranking = 2.4409970201354keywords = spindle, cell (Clic here for more details about this article) |
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