1/14. Mucosa-associated lymphoid tissue-type lymphomas occurring in post-transplantation patients.Post-transplantation lymphoproliferative disorders (PTLDs) are usually Epstein-Barr virus (EBV)-associated B-cell lymphoproliferative disorders that vary in their morphologic spectrum. Extranodal marginal zone lymphomas of the mucosa-associated lymphoid tissue-type (MALT-type) have not been considered to be part of this spectrum. The authors encountered five such cases recently. The clinical, histopathologic, and immunophenotypic features are reported. There were three men and two women with a mean age of 51.2 years (range, 48-63 years). Two patients were cardiac transplant recipients, two patients were liver transplant recipients, and the remaining patient was a renal transplant patient. Sites of lymphoma were the stomach in three patients and the parotid gland in two patients. Mean time to the lymphoma was 84 months after transplantation. All patients had morphologic features of low-grade extranodal marginal zone lymphomas of the MALT-type, and helicobacter pylori was present in all three gastric cases. All patients exhibited the B-cell immunophenotype and were negative for EBV by in situ hybridization. These lymphomas were treated with a variety of modalities, including reduction of immunosuppression, antibiotics, surgical resection, radiation therapy, and chemotherapy. At last follow-up, one patient had developed signet ring adenocarcinoma at 27 months but had no evidence of PTLD, one patient relapsed at 17 months but is alive with stable disease at 24 months, and the remaining patients were alive without disease at 11, 12, and 14 months. Extranodal low-grade MALT-type lymphomas can occur in the post-transplantation setting and generally develop years after transplant. As seen in immunocompetent patients, EBV appears to play no role in the pathogenesis of these lymphomas. These lymphomas appear to have more in common with MALT-type lymphomas in nonimmunocompromised patients than conventional PTLDs, although they occur in "at-risk" patients due to their immunosuppressive therapy. These lymphomas do not appear to be clinically aggressive. Recognition of MALT-type lymphomas in the post-transplantation setting as an indolent disease avoids unnecessary treatment.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/14. Natural killer-like T-cell lymphoma of the parotid in a patient infected with human immunodeficiency virus.A 42-year-old man with acquired immunodeficiency syndrome developed a mass of the right parotid gland and multiple hepatic masses. hematoxylin-eosin-stained sections of the parotid lesion showed a diffuse infiltrate of large mononuclear cells with vesicular nuclei and prominent nucleoli, consistent with a non-Hodgkin lymphoma. Immunohistochemical stains demonstrated expression of the T-cell markers CD3 and UCHL-1, as well as latent membrane protein 1 and T-cell intracellular antigen 1. flow cytometry showed surface expression of CD2, CD3, CD7 (dim), CD8, and CD56. CD5 was not expressed. Molecular evaluation by polymerase chain reaction demonstrated monoclonal rearrangement of the T-cell receptor gamma gene. Epstein-Barr virus early rna and human immunodeficiency virus rna were demonstrated by in situ hybridization. To our knowledge, this is the first reported case of T-cell lymphoma of the parotid in a patient infected with human immunodeficiency virus. After 2 separate chemotherapy regimens, the patient achieved clinical remission for 1(1/2) years; he then developed progressive pulmonary lesions and died.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/14. Cytogenetic and fluorescence in situ hybridization analysis of a basal cell adenocarcinoma of the mandible.Basal cell adenocarcinoma (BCAC) of the salivary glands is rare. Distant metastasis to the mandible from a salivary gland tumor is also considered rare. The cytogenetic finding of a case of metastatic BCAC of the mandible is described. We are unaware of earlier reports regarding cytogenetic findings of BCAC either at the primary site or at a distant metastasis site. An 80-year-old female with primary BCAC of the parotid salivary gland underwent parotidectomy and chemotherapy. One year later, a metastatic lesion in the mandible was found. Tissue specimens from the mandibular lesion were tested by the following pathologic methods: hematoxylin-eosin and immunohistochemistry for CK8/18, CK/903, vimentin, and smooth muscle actin. The characteristic histologic architecture of BCAC found in the mandible was similar to that of the earlier findings of the tumor in the parotid gland. A fresh sample from the mandibular lesion was examined by cytogenetics and fluorescence in situ hybridization (FISH), using centromeric probes for chromosomes 4, 8, 10, 18, and 22. A paraffin-embedded sample of the primary tumor was also examined by FISH. Cytogenetic and FISH analyses of the mandibular metastatic lesion revealed a clone with a pericentric inversion of chromosome 17 and a clone with trisomy 4, respectively. trisomy 4 was also found in the paraffin-embedded samples of the primary parotid tumor.- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |
4/14. Epstein-Barr virus associated lymphoepithelial carcinoma of the parotid gland; a clinicopathological report of three cases.Lymphoepithelial carcinoma is a relatively uncommon malignant tumor of the salivary gland demonstrating malignant epithelial cells with dense lymphoid stroma. The authors report three cases of lymphoepithelial carcinoma associated with Epstein-Barr virus of the right parotid gland with clinically presenting as painless, gradual enlargement of the preauricular mass. The histopathologic examination of the parotid gland is characterized by malignant epithelial cells with dense lymphoid stroma. Immunohistochemical stains show positive reactivity to cytokeratin and p53 in malignant epithelial cells. in situ hybridization of the Epstein-Barr virus-encoded Ribonucleic acid shows positivity in malignant epithelial cells. Clinical and pathologic features with relevant literatures are discussed. These are the first reported cases of primary parotid lymphoepithelial carcinoma associated with Epstein-Barr virus infection in thailand and Southeast asia.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/14. Warthin's tumor with malignant lymphoma. dna analysis of paraffin-embedded tissue.The authors report a case of malignant lymphoma, small lymphocytic type, involving the lymphoid stroma of a Warthin's tumor of the parotid gland. This was confirmed by the presence of a monoclonal immunoglobulin heavy chain gene rearrangement, demonstrated by Southern blot hybridization of dna extracted from paraffin-embedded tissue. Similar techniques showed only germline immunoglobulin gene bands in two control cases of Warthin's tumor.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
6/14. Epstein-Barr virus (EBV)-associated undifferentiated carcinoma of the parotid gland.A case of undifferentiated carcinoma of the salivary gland occurring in the parotid gland of a southern Chinese was reported. Tumour cells showed immunofluorescence for Epstein-Barr virus (EBV)-associated nuclear antigen, and dna hybridization demonstrated the presence of EBV-dna in tumour tissue. The findings in this case, together with previous reports, suggest a causal relationship between EBV and salivary gland carcinoma. The relationships between EBV and undifferentiated epithelial tumours of the salivary glands, nasopharynx and thymus are also discussed.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
7/14. hepatitis c virus within a malignant lymphoma lesion in the course of type II mixed cryoglobulinemia.hepatitis c virus (HCV) has been implicated as the major etiologic factor sustaining B-cell clonal expansion in type II mixed cryoglobulinemia (MC). A putative pathogenetic role of HCV in the development of MC-associated B-cell malignancies has also been speculated. We report for the first time the localization of HCV within a parotid non-Hodgkin's lymphoma (NHL) lesion in the course of HCV-related type II essential MC, an important step to implicate any infectious agent in the lymphomagenesis. Plus and minus strand HCV rna was first demonstrated by polymerase chain reaction on the whole rna from the lesion. Further immunohistochemical studies localized HCV c22 proteins in the residual ductal or acinar parotid structures, which also abnormally expressed hla-dr antigens. Weak c22 signals were inconstantly detected in cells strictly confined around the residual epithelium, while all the remaining infiltrating cells in the parotid lesion stained c-22-negative. Staining for c33 and c100 HCV antigens was negative. in situ hybridization (ISH) studies again identified the residual parotid epithelial cells as the site of HCV infection and replication in the NHL lesion. Sialotropic viruses previously involved in lymphoproliferation, ie, Epstein-Barr virus and human herpesvirus-6, were absent in the same tissue lesion. According to the current models of B-cell lymphomagenesis, a role of HCV as an exogenous antigenic stimulus should be considered for NHL development in the present case, whereas malignant B cells do not appear permissive of active HCV replication. Further efforts would be worthwhile to clarify a role of HCV infection in the development of some B-cell malignancies.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
8/14. Combined strategy of conventional cytogenetics, fluorescent in situ hybridization and chromosome morphometry for analysis of parotid gland tumor.The limiting factors in conventional cytogenetic analysis of cell culture, especially of solid tumors, include insufficient metaphases, overgrowth of abnormal mitotic cells by normal cells, and suboptimal quality of harvesting and banding. Despite the availability of numerous protocols to induce G-banding, as well as Q-, R-, and C-banding, occasions still arise in which the analysis is severely limited by these factors and incomplete conclusions are often drawn as to the precise nature of the chromosomal abnormality, if indeed any can be detected. By adopting a rational approach of (1) close monitoring of cultures and rapid harvesting as soon as it is feasible, and (2) analysis of available metaphases by a combination of the GTG technique, fluorescent in situ hybridization (FISH), and chromosome morphometry using a graphic arts tool, a significant improvement in success rate may be more readily achieved. Here pathological and cytogenetic data are presented of a case of parotid gland carcinoma ex mixed tumor with the karyotype of 46, XX, del(5)(q12), dir ins(8;5)(q12;q12qter), add(12)(p13)/46, XX. This case is utilized to illustrate the importance of application of our combined strategy.- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |
9/14. Spindle cell malignant lymphoepithelial lesion of the parotid gland: clinical, light microscopic, ultrastructural, and in situ hybridization findings in one case.Malignant lymphoepithelial lesions (MLEL) are rare tumors of the salivary glands that show high incidence in Inuit Canadians, Alaskans, and greenland Eskimos. The tumors are usually anaplastic or poorly differentiated squamous cell carcinomas. Focal spindle cell elements have been rarely reported. The tumors have been epidemiologically linked to Epstein-Barr virus infection. We present a case of malignant lymphoepithelial lesion showing exclusive spindle cell morphology. The patient is a 44-year-old male Inuit Canadian who presented with a long-standing history of a left parotid mass. The mass did not show evidence of rapid growth or facial nerve involvement. Parotidectomy was performed. The tumor was histologically composed of spindle cells nodules in a background of lymphocytes. The spindle cells showed no evidence of cytologic atypia but were mitotically active. Immunohistochemical staining for low-molecular-weight cytokeratin was only focally positive. The differential diagnosis included a mesenchymal neoplasm and malignant lymphoepithelial lesion. Electron microscopic examination confirmed the squamous nature of the neoplasm. Intracytoplasmic viral particles were also identified ultrastructurally. in situ hybridization for Epstein-Barr virus mRNA using a 30-base oligonucleotide probe specific for the EBER-1 gene showed very high level of expression in the tumor cells. No expression was noted in the adjacent parotid gland tissue. Our findings confirm the squamous nature of malignant lymphoepithelial lesions despite the spindle cell morphology occasionally seen in these neoplasms. They also confirm the strong role of Epstein-Barr virus infection in the pathogenesis of these tumors. This may have further diagnostic and therapeutic implications.(ABSTRACT TRUNCATED AT 250 WORDS)- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |
10/14. Undifferentiated carcinoma of the parotid gland in a white patient: detection of Epstein-Barr virus by in situ hybridization.paraffin sections of an undifferentiated salivary gland carcinoma of lymphoepithelioma type, arising in a white (Greek) patient and confirmed by immunohistochemistry, were examined for the presence of Epstein-Barr virus (EBV), using in situ hybridization to detect EBV-specific EBER1 message. Epstein-Barr virus was detected in malignant epithelial cells, but was not found in lymphoid stroma or in residual benign salivary epithelium. These results confirm the existence of an association between EBV and tumor cells of undifferentiated carcinoma of parotid gland. This is the first demonstration of EBV in a salivary gland lymphoepithelioma arising in a non-Eskimo, white patient. This finding suggests that the association of EBV with undifferentiated salivary gland carcinoma may exist in geographic regions remote from greenland.- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |
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