Cases reported "Carcinoma"

Filter by keywords:



Filtering documents. Please wait...

1/29. Pigmented intraosseous odontogenic carcinoma of the maxilla: a pediatric case report and differential diagnosis.

    We report a pigmented intraosseous odontogenic carcinoma of the maxilla occurring in a 6-year-old Japanese boy. Grossly, the tumor showed solid, gray-yellow, and markedly pigmented appearance. histology showed neoplastic growths of atypical epithelial cells that occasionally contained melanin pigments. melanocytes with dendritic processes were often found in the tumor cell clusters, and solitary or aggregated melanophages were scattered within the dense fibrovascular stroma. The tumor cells were diffusely positive for cytokeratins and epithelial membrane antigen, and focally positive for vimentin, neuron specific enolase, neurofilament protein, carcinoembryonic antigen, and amelogenin. Ultrastructural studies showed well-developed intercellular junctions, mainly desmosomes, and glycogen particles. In addition, some tumor cells contained melanosomes and/or a few neurosecretory granules. We consider that the present tumor suggests a close association of ectoderm, mesenchyma, and neuroectoderm in embryogenesis of the tooth, and can raise a diagnostic confusion with melanotic neuroectodermal tumor.
- - - - - - - - - -
ranking = 1
keywords = desmosomes
(Clic here for more details about this article)

2/29. Cutaneous spindle cell carcinoma following basal cell carcinoma.

    A spindle cell carcinoma arose three years after the seeming excision of a so-called "infiltrative" basal cell carcinoma (IBCC) in the cheek of an 87-year-old Japanese woman. The patent had no history of irradiation. The tumor was composed of short fascicles and whorling arrangements of spindle to polygonal cells without residual IBCC. Immunohistochemically, the tumor was positive for vimentin, cytokeratin 8 & 18, epithelial membrane antigen, and alpha-smooth muscle actin. Ultrastructurally, the tumor cells had tonofilaments and desmosomes. The patient died after a local recurrence with metastatic lesions in the lung and the neck lymph nodes that were indicated by CT scanning and MRI at nine months after diagnosis. This case and others support the concept that spindle cell carcinoma can pursue an aggressive clinical course.
- - - - - - - - - -
ranking = 1
keywords = desmosomes
(Clic here for more details about this article)

3/29. Filamentous inclusions of unusual composition and architecture in a metastatic tumor showing myoepithelial differentiation.

    A hyaline/eosinophilic cytoplasmic inclusion is described in a metastatic tumor occurring in the omentum and bowel of a 32-year-old white woman. The tumor was essentially of round cell type; was positive for cytokeratin, actin, and S-100 protein by immunohistochemistry; and showed desmosomes (maculae adherentes), tonofibrils, modestly developed myofilaments with focal densities, and a basal lamina by electron microscopy. It was therefore interpreted as showing myoepithelial differentiation. Nearly all cells possessed a large, rounded cytoplasmic inclusion that was architecturally unusual, consisting of intermediate filaments intermingled with lattices of fine filaments. The inclusions exhibited an additionally unusual immunohistochemical staining for both cytokeratin and actin. A comparison with cases described in the literature is made.
- - - - - - - - - -
ranking = 1
keywords = desmosomes
(Clic here for more details about this article)

4/29. Spindle cell carcinoma of the breast.

    A case of spindle cell carcinoma of the breast in association with myoepithelial cell hyperplasia is presented. Immunocytochemistry demonstrated labelling of tumour cells for cytokeratin, vimentin and S-100 protein. Electronmicroscopy showed desmosomes and bundles of tonofilaments as well as fine filaments in the cytoplasm. The findings in the present case point to the metaplastic spindle cell nature of squamous carcinoma of the breast. The possible role of myoepithelial cells in the origin of the spindle cell component is discussed.
- - - - - - - - - -
ranking = 1
keywords = desmosomes
(Clic here for more details about this article)

5/29. Anaplastic thyroid carcinoma with osteoclast-like giant cells. A clinicopathologic, immunohistochemical, and ultrastructural study.

    Two anaplastic thyroid carcinomas with osteoclast-like giant cells (OCL-GC) are reported. light microscopically, one case resembled an aneurysmal bone cyst with cellular connective-tissue septae separating cavernous, blood-filled sinuses. The second case had sheets of anaplastic cells and a separate focus of papillary carcinoma without areas of transition. Multinucleate OCL-GC, pleomorphic mononuclear cells, and histiocytoid mononuclear cells with nuclei similar to those within the OCL-GC were seen in each case. With formalin-fixed, paraffin-embedded tissue, the majority of OCL-GC and histiocytoid mononuclear cells in both cases showed immunoreactivity using monoclonal antibodies to vimentin and KP-1, with the latter preparation directed against cells of monocytic/histiocytic lineage. Staining for keratin, epithelial membrane antigen, neuron-specific enolase, chromogranin, calcitonin, and thyroglobulin was negative in all cell types. Ultrastructural examination of one case showed two distinct types of mononuclear cells--one with morphologic characteristics similar to those of the OCL-GC, and another with pleomorphic nuclei and short cytoplasmic extensions joined by poorly formed desmosomes. The findings indicate that the anaplastic thyroid carcinomas studied represent poorly differentiated epithelial tumors infiltrated by reactive OCL-GC of monocytic/histiocytic lineage apparently derived from histiocytoid mononuclear cells via cellular fusion.
- - - - - - - - - -
ranking = 1
keywords = desmosomes
(Clic here for more details about this article)

6/29. carcinoma of the breast with metaplasia to chondrosarcoma: a light and electron microscopic study.

    Two carcinomas of the breast containing large areas of sarcomatous tissue were studied by light and electron microscopy. In one of these, the sarcomatous element was frankly cartilaginous and in the other, predominantly myxoid but with small cartilaginous-looking foci. By light microscopy, a highly suggestive metaplastic transition could be traced from cells within the epithelial nests to those within the sarcomatous lobules. Ultrastructurally, cells in the former region showed epithelial characteristics and those in the latter region, mesenchymal and/or cartilaginous features. The carcinomatous cells contained desmosomes and formed intercellular spaces lined by microvilli; a few cells showed prominent profiles of rough endoplasmic reticulum. In the first case, the cells in the immediate vicinity of the epithelial nests and those in the fully developed cartilaginous regions showed a progressive dilatation of their endoplasmic reticulum to form large sac-like structures filled with a finely granular and floccular material. The intercellular matrix was electron lucent and contained scattered dense particles, fibrillo-granular material and collagen fibres. Condensation of this material at some distance from the cell resulted in the formation of lacunae. In the second case, the cells in the myxoid areas also showed prominent dilatation of endoplasmic reticulum.
- - - - - - - - - -
ranking = 1
keywords = desmosomes
(Clic here for more details about this article)

7/29. Microcystic adnexal carcinoma: a light microscopic, immunohistochemical and ultrastructural study.

    We report a case of microcystic adnexal carcinoma (MAC) occurring on the upper lip of an 82-year-old woman. Microscopically the tumor showed both pilar and sweat gland differentiation, involved the entire dermis and subcutaneous tissue, and invaded perineural spaces. Immunoperoxidase studies revealed carcinoembryonic antigen to be present in the ductal lining cells and in the amorphous content in the lumen, confirming sweat gland differentiation. The S-100 protein was positive in dendritic cells within the solid cell nests, but negative in cells lining cystic spaces. Ultrastructural study confirmed that the neoplasm was composed of two components, with pilar and eccrine differentiation. The former showed concentric layers of squamous epithelial cells with well-developed desmosomes and cytofilaments. The latter had ductal and alveolar structures; the ultrastructural features included: i) numerous villous folds of plasma membrane to interdigitate each other by focal desmosomes, ii) aggregates of cytofilaments, and iii) basally located myoepithelial cells which were separated from the surrounding stroma by rather thick basement membrane. In addition, distinct amyloid deposition was also observed on ultrastructural examination. To our knowledge, amyloid deposition has not been previously reported in MAC.
- - - - - - - - - -
ranking = 2
keywords = desmosomes
(Clic here for more details about this article)

8/29. Malignant small-cell epithelial tumor of the peritoneum coexpressing mesenchymal-type intermediate filaments.

    A 28-year-old man with a large abdominal mass was found to have a tumor involving the peritoneum that had no other apparent primary origin. By light microscopy, the histologic pattern of the tumor was that of a small-cell epithelial neoplasm. Electron-microscopic examination demonstrated desmosomes and paranuclear aggregates of intermediate filaments. Immunohistochemical studies revealed reactivity for keratin, desmin, and vimentin. The globoid staining observed for the last two markers correlated with the paranuclear concentration of intermediate filaments observed by electron microscopy. We believe this case represents an unusual small-cell epithelial tumor, expressing mesenchymal-type intermediate filaments, that should be distinguished from other small-cell neoplasms.
- - - - - - - - - -
ranking = 1
keywords = desmosomes
(Clic here for more details about this article)

9/29. Spindle cell carcinoma of cornea and conjunctiva with pseudosarcomatous metaplasia. light microscopic, electron microscopic and immunohistochemical findings in 2 patients.

    We studied the electron microscopic and immunohistochemical findings in two elderly patients with spindle cell carcinoma of the cornea and conjunctiva. By light microscopy, correct diagnosis was made by finding the transition between the pleomorphic spindle shaped tumor cells and the overlying squamous epithelium. Ultrastructural findings indicated that squamous cell origin included tonofilament-associated desmosomes and keratohyaline granules in the tumor cells. Positive immunohistochemical staining with antikeratin antibodies provided further evidence to prove the origin of spindle cell carcinoma. Follow-up of the two patients showed the malignant tumor to be quite aggressive in terms of intraocular invasion in the first patient and local recurrence in the second.
- - - - - - - - - -
ranking = 1
keywords = desmosomes
(Clic here for more details about this article)

10/29. Primary thyroid thymoma: a distinct clinicopathologic entity.

    A 51-year-old man presented with a paratracheal tumor. He had undergone resection of a thyroid tumor 15 years previously; at that time, the histologic diagnosis had been anaplastic carcinoma. When the tumor recurred, the presumptive clinical diagnosis was medullary thyroid carcinoma. Histologic examination revealed a poorly differentiated epithelial tumor with immunoreactivity for keratins, carcinoembryonic antigen, and, focally, S-100 protein. The tumor was negative for calcitonin and thyroglobulin. There were scattered lymphocytes and plasma cells. Ultrastructural examination showed elongated epithelial cells with prominent desmosomes and bundles of cytoplasmic tonofilaments but no secretory granules; amyloid was not present ultrastructurally or histochemically. The characteristic ultrastructural and immunocytochemical features and the clinical behavior of this tumor verify the existence of primary thyroid thymoma. This new primary thyroid neoplasm is of clinical importance, considering the more benign behavior of primary thyroid thymoma than of other tumors in the differential diagnosis of this lesion.
- - - - - - - - - -
ranking = 1
keywords = desmosomes
(Clic here for more details about this article)
| Next ->


Leave a message about 'Carcinoma'


We do not evaluate or guarantee the accuracy of any content in this site. Click here for the full disclaimer.