1/22. Giant cell angiofibroma of the nasolacrimal duct.PURPOSE: To describe clinical and histologic features of the first case, to our knowledge, of giant cell angiofibroma located in the nasolacrimal duct region in a 28-year-old woman. methods: Interventional case report. A left nasolacrimal duct tumor was excised en bloc by lateral rhinotomy. Histopathologic examination was performed with the use of light microscopy. Immunohistochemical staining included S-100 protein, muscle-specific actin, desmin, myoglobin, vimentin, and CD34. RESULTS: The lesion was characterized by haphazardly arranged oval to spindled cells, a myxoid and collagenous stroma, multinucleated giant cells, prominent blood vessels, and pseudovascular spaces. Tumor cells were strongly positive for vimentin and CD34 and were negative for other antigens. After excision, there has been no recurrence over 4 years of follow-up. CONCLUSIONS: Originally described as an orbital tumor, giant cell angiofibroma also may occur in the nasolacrimal duct and lacrimal sac region. This mesenchymal neoplasm should be included in the differential diagnosis of lacrimal drainage system tumors.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/22. Primary mediastinal giant cell tumors: a clinicopathologic and immunohistochemical study of two cases.Two cases of posterior mediastinal giant cell tumors are presented. The patients are a woman and a man, 31 and 18 years old, respectively. One of the patients had symptoms of paresthesias while the other was completely asymptomatic. Complete physical examination did not disclose evidence of tumor elsewhere. Neither patient had a previous history of malignancy. Surgical resection was performed. Histologically, both tumors were composed of a proliferation of osteoclast-like giant cells associated with a mononuclear cell population composed of oval and spindle cells. Mitotic activity and mild cellular atypia were present in the mononuclear cell component. No evidence of necrosis or hemorrhage could be demonstrated in either case. Immunohistochemically, both tumors showed strong positive reaction in the mononuclear component for antibodies against vimentin and CD68, while keratin, epithelial membrane antigen, CD45, S-100 protein, and desmin were negative. On clinical follow-up, both patients are alive and well without evidence of recurrence or metastasis 6 and 108 months after surgery. The present cases highlight the ubiquitous distribution of soft tissue giant cell tumors and the importance of considering these tumors in the differential diagnosis of posterior mediastinal neoplasms.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
3/22. A malignant ovarian tumor with osteoclast-like giant cells.Neoplasms that are composed focally, predominantly, or exclusively of osteoclast-like giant cells admixed with variably pleomorphic mononuclear cells have been described in a wide variety of organs. In this report, we describe the case of a 76-year-old woman with an 8-cm tumor that appeared to be localized to the ovary, that was composed predominantly of diffusely distributed, bland-appearing osteoclast-like giant cells admixed with pleomorphic mononuclear cells, and that was not associated with an ovarian cystic neoplasm. hemorrhage, large zones of necrosis, and a high mitotic index were the other characteristics of the tumor. Immunohistochemically, the mononuclear cells were strongly positive for vimentin and proliferating cell nuclear antigen and were negative for keratin AE 1/3, CAM 5.2, cytokeratin 7, epithelial membrane antigen, beta-human chorionic gonadotropin, desmin, smooth muscle actin, p53, leukocyte common antigen, S-100, inhibin, alpha-1-antichymotrypsin, and CD68. The osteoclast-like giant cells displayed immunoreactivity for CD68, vimentin, alpha-1-antichymotrypsin, and leukocyte common antigen only. Ultrastructurally, rare intercellular junctions were present between mononuclear cells, suggestive of an epithelial histogenesis. Less than a dozen ovarian lesions with the "giant cell" designation have been described, and most of these cases are thought to be analogous to the "sarcoma-like" nodules or other such lesions that have a well-known association with ovarian cystic neoplasms. Our case, in contrast, did not have an easily identifiable epithelial component and demonstrated both an infiltrative border and vascular invasion. This is, to the authors' knowledge, the first detailed clinicopathologic description of such a case as an ovarian lesion.- - - - - - - - - - ranking = 4keywords = antigen (Clic here for more details about this article) |
4/22. Osteoclast-like giant cell tumour of the gallbladder.We describe a rare carcinoma of the gallbladder containing osteoclast-like giant cells. Well-differentiated adenocarcinoma was found in the mucosa of the fundus, and osteoclast-like giant cells were present mainly in a haemorrhagic mass protruding from the mucosal surface. The metastatic hepatic tumour was composed chiefly, if not exclusively, of osteoclastoma-like cells, but minute carcinomatous elements were also present. There was an apparent transition between the giant cells and tubular structures in both the gallbladder tumour and hepatic tumour. However, ultrastructural study did not reveal any evidence of epithelial differentiation in the giant cells. Immunohistochemical studies suggested that the mononuclear and giant cells were mesenchymal and histiocytic in nature (vimentin and factor xiiia positive). A few exceptional giant cells transforming from the fine tubular structure were positive for epithelial membrane antigen. In conclusion, the osteoclast-like giant cell tumour component was thought to represent mesenchymal metaplasia in pre-existent adenocarcinoma.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
5/22. Osteoclast-like giant cell tumor of the pancreas associated with mucus-secreting adenocarcinoma. Case report and discussion of the histogenesis.BACKGROUND/AIMS: The osteoclast-like giant cell tumor of the pancreas is a rare entity that closely resembles giant cell tumor of the bone, which has also been observed in many other organs. Some tumors also contain areas of ductal adenocarcinoma. Conflicting opinions exist regarding the tumor origin, whether it is mesenchymal or epithelial, neoplastic or reactive. methods: We report the case of a 69-year-old Brazilian man with a mass in the head of the pancreas, the histological examination of which revealed a predominant component of osteoclast-like giant cells within a background of pleomorphic mononuclear cells with osteoid formation and other areas composed of conventional mucus-secreting adenocarcinoma. RESULTS: immunohistochemistry showed that carcinoma cells of the usual type expressed epithelial antigens (EMA and cytokeratin) and lysozyme; the giant cells expressed vimentin, CD45, CD68, and lysozyme; and the mononuclear cells expressed macrophage marker (HAM56), vimentin, and lysozyme, and only some of them expressed epithelial markers, CD45, and CD68. CONCLUSION: Our immunohistochemical findings reveal that the giant cells in this case are of mesenchymal origin may be from the bone marrow cells. We believe that it is important to determine the histogenesis in each case to carry out the pertinent adjuvant therapy.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
6/22. Mixed osteoclastic/pleomorphic giant cell tumor of the pancreas: a case report.BACKGROUND: Mixed giant cell tumor (MGCT) of the pancreas is a rare malignant neoplasm. The tumor contains pleomorphic giant cells (PGC), pleomorphic mononuclear cells (PMC) and osteoclastic giant cells (OGC). We describe the first fine needle aspiration biopsy (FNAB) diagnosis of this tumor. CASE: A 76-year-old woman was discovered (on imaging studies) to have an apparently inoperable mass in the head of the pancreas. Computed tomography-guided FNAB showed a malignant neoplasm with features of an MGCT. PGC/PMC, OGC and spindle cells were present. The PGC/PMC expressed epithelial antigens, pancytokeratin, CAM 5.2, AE1/AE3 and epithelial membrane antigen (EMA). The spindle cells focally stained for EMA. OGC were negative for the epithelial antigens. OGC, PGC/PMC and the spindle cells were positive for the mesenchymal marker vimentin. CONCLUSION: FNAB was instrumental in making the diagnosis of a rare pancreatic tumor, MGCT. Immunocytochemistry was helpful in making a definitive diagnosis and suggested that MGCT is a carcinosarcoma like neoplasm. The morphology and immunocytochemical profile raise the possibility that osteoclastic giant cell tumor and pleomorphic giant cell tumor may be different morphologic and biologic expressions of the same tumor.- - - - - - - - - - ranking = 3keywords = antigen (Clic here for more details about this article) |
7/22. Atypical carcinoid tumor of the lung, associated with giant-cell transformation in bone metastasis.A case of neuroendocrine lung tumor located beneath the pleura in a 71-year-old woman is reported. At autopsy, the tumor was found to have metastasized to the bones and liver without involving the hilar lymph nodes. Histologically, the tumor cells at the primary site and in the liver metastasis exhibited a carcinoid-like organoid structure, whereas pleomorphic giant cells were noted in the bone metastasis. The argyrophilic tumor cells were immunoreactive for neuron-specific enolase, chromogranin a, serotonin, calcitonin, calcitonin gene-related peptide, gastrin-releasing peptide, neuropeptide y, gastrin, pancreatic polypeptide, glicentin, the alpha-subunit of human chorionic gonadotropin, keratin, epithelial membrane antigen, Leu M1 and carcinoembryonic antigen. Electron microscopy revealed abundant neurosecretory granules in the cytoplasm. This was considered to be a rare case of neuroendocrine lung tumor showing carcinoid-like histology at the primary site and large-cell transformation in bone metastasis.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
8/22. Fine-needle aspiration cytology of osteoclastic giant-cell tumor of the pancreas.Osteoclastic giant-cell tumor (OGCT) of the pancreas is a rare tumor. We present the fine-needle aspiration (FNA) and bile cytology findings of an OGCT arising in the head of the pancreas in a 72-yr-old male, along with immunocytochemical studies that were done on the cytologic material. The smears showed numerous giant cells with clustered, overlapping, uniform, bland-appearing nuclei with prominent nucleoli consistent with osteoclastic-type multinucleated giant cells. A second population of mononucleated cells appearing singly or in groups having similar nuclear features was also present. Immunocytochemical studies performed on the FNA and bile duct fluid material demonstrated positive staining of the malignant cells for vimentin, alpha-1 antichymotrypsin, and alpha-1 antitrypsin and negative staining for high- and low-molecular-weight cytokeratin, pooled monoclonal cytokeratin, epithelial membrane antigen, and carcinoembryonic antigen. Although not definitive, these studies are supportive of a mesenchymal-stromal histogenesis of this unusual pancreatic malignancy.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
9/22. Osteoclast-like giant cell tumor of the pancreas: immunophenotypic similarity to giant cell tumor of bone.An immunophenotype was performed on an osteoclast-like giant cell tumor of the pancreas using a panel of antibodies to epithelial and leukocyte antigens. Several antibodies to cytokeratin and carcinoembryonic antigen were negative in the tumor. Osteoclast-like cells were positive for CD4, CD13, CD45, CD68, CD71, and vimentin, but negative for lysozyme and HLA-DR. Mononuclear tumor cells were positive for CD4, CD11c, CD13, CD14, CD45, CD68, CD71, HLA-DR, and vimentin, but negative for lysozyme. The phenotype is similar to that previously described for giant cell tumor of bone. The osteoclast-like cell phenotype is also similar to that reported for normal osteoclasts. The findings support a nonepithelial origin for osteoclast-like giant cell tumor of the pancreas, and suggest a derivation similar to giant cell tumor of bone.- - - - - - - - - - ranking = 2keywords = antigen (Clic here for more details about this article) |
10/22. The osteoclast-type giant cell tumor of the pancreas.We present a case report of osteoclast-type giant cell tumor of the pancreas and review the literature concerning this rare neoplasm, the histogenesis of which is uncertain. Electron microscopic features have suggested stromal, histiocytic, and epithelial origins to different investigators. Analysis of the present case supports and epithelial origin, with positive immunocytochemical staining for carcinoembryonic antigen and for low molecular weight keratin in the mononuclear and in some osteoclastlike giant cells. These tumor cells did not stain for mesenchymal markers (lysozyme, alpha 1-antitrypsin, alpha 1-antichymotrypsin, S100 protein). Zymogen granules, desmosomes, and zonulae occludentes were identified ultrastructurally and further support an epithelial derivation.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
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