1/7. Follicular dendritic cell tumor of the parapharyngeal region.BACKGROUND: Follicular dendritic cell (FDC) tumors are rare. A majority of the reported cases were confined to the lymph nodes. We report a case of FDC tumor occurring in the parapharyngeal region in a 45-year-old woman. methods: Characteristic histopathologic features of the excised primary and recurrent parapharyngeal tumors in conjunction with immunohistochemistry and electron microscopy helped us to arrive at a diagnosis of FDC tumor. RESULTS: Histopathology of primary excision revealed a lobulated tumor with a suggestion of ill-defined whorls. The most striking feature was regular occurrence of aggregates of lymphocytes within the tumor, especially around the blood vessels. The anatomic location together with the histology indicated the possibilities of either a meningioma, a salivary gland tumor, or a nerve sheath tumor. Immunostains for cytokeratin (CK), S-100 protein, and smooth muscle actin (SMA) were negative. However, the tumor cells showed strong immunoreactivity for epithelial membrane antigen (EMA) and vimentin. A diagnosis of parapharyngeal meningioma appeared to be the closest possibility. One year later, the patient developed a recurrence at the same site. A reexcision showed an identical tumor with an additional feature of lymphatic embolization and angioinvasion. A review of the entire case with further immunoreactivity for CD21 and CD35 confirmed the diagnosis of FDC. CONCLUSIONS: Follicular dendritic cell tumor has distinctive morphologic features and immunohistochemical profile. It is also characterized by considerable potential for recurrences.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
2/7. Extranodal follicular dendritic cell sarcoma of the head and neck region: three new cases, with a review of the literature.Extranodal follicular dendritic cell (FDC) sarcoma of the head and neck region is uncommon, with 16 well-documented cases previously reported (four in the tonsil, four in the pharynx, two in the palate, five in the soft tissue, and one in the thyroid). We here report an additional three cases of extranodal FDC sarcoma in the tonsil (two cases) and pharynx (one case). In these new cases, the neoplastic cells were arranged in diffuse, fascicular, and vaguely whorled growth patterns. A background lymphocytic infiltrate was sprinkled throughout the neoplasms, with focal prominent perivascular cuffing. Scattered multinucleated giant cells were present. Immunohistochemically, tumor cells were strongly and diffusely positive for follicular dendritic cell markers CD21 and CD35. Tumor cells were diffusely positive for fascin and negative for leukocyte common antigen, S-100 protein, cytokeratin, and Epstein-Barr virus (EBV) latent membrane protein-1 (EBV-LMP). EBV was also not detected in the tumor cells by in situ hybridization for EBV-encoded RNAs. FDC sarcomas are probably an underrecognized neoplasm, especially when they occur in extranodal sites in the head and neck region. Two of the three new cases we report were initially misdiagnosed, and five cases of extranodal FDC sarcoma in the head and neck region reported in the recent literature were initially misdiagnosed. Our aim is to complement the current understanding of this neoplasm and alert pathologists to this rare entity in this region to avoid misdiagnosis. Recognition of extranodal FDC sarcoma requires a high index of suspicion, but this tumor has numerous distinctive histological features that should bring the neoplasm into the differential diagnosis. Confirmatory immunohistochemical staining with follicular dendritic cell markers such as CD21 and/or CD35 is essential for the diagnosis. Correct characterization of this neoplasm is imperative given its potential for recurrence and metastasis.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
3/7. Pharyngeal pituitary non-functioning adenoma with normal intra-sellar gland: massive tumor shrinkage on octreotide therapy.OBJECTIVE: Functioning or non-functioning ectopic tumors may develop from pharyngeal pituitary remnants. They constitute <1% of all obstructive pharyngeal masses and they have a strong tendency to bleed. We report a case of a non-functioning ectopic pituitary adenoma of the rhino-pharynx studied over a long-term somatostatin analog treatment. PATIENT AND TREATMENT: A 60-Year-old woman presented with severe posterior epistaxis. She had complained of nasal obstruction for the past 2 Years. magnetic resonance imaging (MRI) and endoscopic examination revealed a 2 cm exophytic, bleeding mass in the cavum, which was judged inoperable, and a biopsy was performed. On immunostaining, tumor cells were positive for pancytokeratins MNF 116 and C11, epithelial membrane antigen, chromogranin and neuron-specific enolase (NSE), and negative for synaptophysin, desmin, actin, estrogen and progesterone receptors, all anterior pituitary hormones and human chorionic gonadotropin. Blood levels of the above hormones and tumor markers were normal, except for a moderate elevation of NSE (33.8 microg/l, normal value <12 microg/l). It was concluded that this was a non-functioning pituitary adenoma of the rhino-pharynx. MRI showed a normal intra-sellar pituitary gland, including the normal bright signal of the posterior lobe. somatostatin receptor scintigraphy (SRS) disclosed intense tracer uptake in the tumor, indicating high somatostatin receptor content. There was also an intense uptake in the intra-sellar pituitary. Therapy with long-acting octreotide was started, 20 mg per Month i.m. RESULTS: The patient has been on octreotide for the last 12 Months. nasal obstruction rapidly subsided and bleeding did not recur. Repeated endoscopic examinations showed rapid tumor reduction, the mass shrinkage being almost complete at 3 Months. This was confirmed by MRI, while SRS showed markedly decreased uptake in the residual tumor and the intra-sellar pituitary, and NSE became normal. CONCLUSION: Pharyngeal pituitary remnant adenomas are rare, but they must be considered in the differential diagnosis of bleeding or obstructive masses of the rhino-pharynx. In this case, the positive SRS influenced the choice of octreotide, as an alternative to surgery. As we show for the first time in this location, octreotide can exert prolonged and marked anti-tumoral effects in non-functioning adenoma.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
4/7. association of Epstein-Barr virus with polymorphic reticulosis.We report a case of polymorphic reticulosis (PR) associated with pharyngeal replication of Epstein-Barr virus (EBV). A 78-year-old man with necrotic inflammatory granulations in the nasal cavities and ulcerative tissue of the tonsils was found to have PR after an initial diagnosis of lethal midline granuloma and was found to have high antibody titers to EBV. EBV-determined nuclear antigen (EBNA) was demonstrated in pharyngeal biopsy specimens by the anti-complement immunofluorescent technique, following which dual immunofluorescence staining, EBNA and T-cell antigen analysis were performed, using a wide variety of monoclonal antibodies. All of the EBNA-positive lymphocytes in the pharyngeal biopsy specimens were found to have exclusively T-cell antigens. This case strongly suggests that some of the cases of PR related to T-cell lymphomas may be closely associated with active EBV infection.- - - - - - - - - - ranking = 3keywords = antigen (Clic here for more details about this article) |
5/7. Infiltration of Leu-3a 3b-positive lymphocytes and expression of human leukocyte antigen DR on tumor tissue induced by radiation therapy.Tumor infiltrating lymphocytes induced by radiotherapy were analyzed by the biotin-avidin-horseradish peroxidase method. At the early dose of 4 Gy (400 rad) of irradiation (2 Gy X 2), remarkable infiltration of lymphocytes was observed surrounding cancer cells. This infiltration was mainly composed of Leu-3a 3b-positive lymphocytes, and human leukocyte antigen DR-positive tumor and interstitial cells were remarkably observed.- - - - - - - - - - ranking = 5keywords = antigen (Clic here for more details about this article) |
6/7. Medullary carcinoma of the thyroid presenting as tumours of the pharynx and larynx.Two cases of medullary carcinoma of the thyroid presenting as tumours of the pharynx and larynx are described. One patient had a tonsillar mass that resembled a carotid body tumour clinically, radiologically and microscopically. The other had an arytenoid tumour with multiple cervical lymph node metastases but without intrathyroidal carcinoma. The endocrine nature of the neoplasms was indicated by the presence of stromal amyloid, cellular argyrophilia and secretory granules whilst the demonstration of calcitonin and carcinoembryonic antigen provided evidence that they were medullary carcinomas.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |
7/7. digeorge syndrome associated with multiple squamous cell carcinomas.Experimental evidence and clinical experiences have have shown that immune mechanisms and cancer are closely related. A case of a 42-year-old man with digeorge syndrome is presented as an interesting example of an impaired immune mechanism and is described in association with multiple squamous cell carcinomas of the upper respiratory system. The congenital absence of the thymus gland in digeorge syndrome results in an absence of a cell-mediated immune response. There are plasma cells and germinal centers in lymph nodes, but lymphocytes in the paracortical areas are sparse. patients wiith digeorge syndrome have no delayed hypersensitivity, cannot be actively sensitized with dinitrochlorobenzene, reject allografts poorly, and have no lymphocytic response to phytohemagglutinin antigens.- - - - - - - - - - ranking = 1keywords = antigen (Clic here for more details about this article) |