1/36. Epstein-Barr virus-associated lymphoproliferative skin lesion with recurrent necrotic papulovesicles of the face.A 24-year-old man showed recurrent necrotic papulovesicles of the face. The cutaneous lesions started with erythema, followed by vesicles, necrosis, and crusting, and leaving depressed scars. light avoidance did not prevent the development of the lesions. Histologic examination revealed lymphoproliferative lesions confined to the skin. Latent Epstein-Barr virus (EBV) infection was detected in the lymphoid cells from the skin lesions by in situ hybridization. A moderate to high dosage of corticosteroids suppressed the development of new skin lesions, but relapses occurred when these systemic corticosteroids were tapered.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/36. Inheritance of chromosomally integrated human herpesvirus 6 dna.Human herpesvirus 6 (HHV-6) genome has been detected in several human lymphoproliferative disorders with no signs of active viral infection, and found to be integrated into chromosomes in some cases. We previously reported a woman with HHV-6-infected Burkitt's lymphoma. fluorescence in situ hybridization showed that the viral genome was integrated into the long arm of chromosome 22 (22q13). The patient's asymptomatic husband also carried HHV-6 dna integrated at chromosome locus 1q44. To assess the possibility of chromosomal transmission of HHV-6 dna, we looked for HHV-6 dna in the peripheral blood of their daughter. She had HHV-6 dna on both chromosomes 22q13 and 1q44, identical to the site of viral integration of her mother and father, respectively. The findings suggested that her viral genomes were inherited chromosomally from both parents. The 3 family members were all seropositive for HHV-6, but showed no serological signs of active infection. To confirm the presence of HHV-6 dna sequences, we performed polymerase chain reaction (PCR) with 7 distinct primer pairs that target different regions of HHV-6. The viral sequences were consistently detected by single-step PCR in all 3 family members. We propose a novel latent form for HHV-6, in which integrated viral genome can be chromosomally transmitted. The possible role of the chromosomally integrated HHV-6 in the pathogenesis of lymphoproliferative diseases remains to be explained.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/36. Epstein-Barr virus associated B-cell lymphoma of brain developing in myelodysplastic syndrome with c-kit mutation (Try-557 -->stop).The first case of B-cell lymphoma of brain in a patient with myelodysplastic syndrome (MDS) was reported. A 68-year-old man was admitted because of anemia, fever, and thrombocytopenia and was diagnosed as having MDS (refractory anemia with excess of blasts) on the basis of the findings of bone marrow aspiration and chromosomal analysis. The patient was followed up without chemotherapy, but a brain tumor appeared after 3 years. Histologic and immunohistologic examinations revealed diffuse large B-cell lymphoma. Mutations of the c-kit proto-oncogene (stem cell factor receptor) and the p53 tumor-suppressor gene were examined in the MDS lesion and malignant lymphoma (ML) by the polymerase chain reaction-single-strand conformational polymorphism (PCR-SSCP) method followed by direct sequencing. The p53 mutation was not found in either MDS or ML, but a nonsense mutation (Try-557 --> stop) in exon 11 of the c-kit, which might lead to dysfunction of tyrosine kinase activity, was detected in MDS. This is the first report of c-kit mutation in MDS. Epstein-Barr virus (EBV) genome was demonstrated in the nucleus of brain ML cells by in situ hybridization with EBV-encoded rna-1 probe. immunohistochemistry showed that the tumor cells expressed latent infection gene products, including EBV nuclear antigen-2 and latent membrane protein-1. This pattern of latent gene expression was Lat III, which is usually found in malignant lymphomas developing in immunocompromised hosts. These findings suggest that a profound pancytopenia in MDS resulted in an immunodeficient condition, after which EBV-positive B-cell lymphoma of brain developed.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/36. Detection of diagnostically critical, often hidden, anomalies in complex karyotypes of haematological disorders using multicolour fluorescence in situ hybridization.Multicolour fluorescence in situ hybridization (M-FISH) simultaneously detects all 24 human chromosomes in unique fluorescent colours. The identification of diagnostically critical gene rearrangement(s) in complex karyotypes of haematological disorders continues to be a challenge. We present five cases in which t(9;11), complex t(8;22), t(12;21) and t(11;14) were detected primarily using M-FISH and were confirmed using locus-specific probes. We conclude that M-FISH can be effective in complete characterization of critical gene rearrangements in haematological disorders.- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |
5/36. Blastic mantle cell lymphoma associated with Burkitt-type translocation and hypodiploidy.Two elderly men with stage IV mantle cell lymphoma (MCL) rapidly developed a leukaemic phase with unusually high blast counts that proved fatal. One lymph node biopsy showed diffuse MCL, the other blastic morphology. In addition to t(11;14), there were t(8;14) and t(1;19) in case 1 and dup(8)(q24q13) in case 2. fluorescence in situ hybridization revealed genomic fusion of IgH/MYC genes in case 1 and an extra copy of C-MYC gene in case 2. The genomic alteration of C-MYC oncogene is probably implicated in the blastic transformation and aggressive behaviour of the disease.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
6/36. Mature B-cell leukemias with more than 55% prolymphocytes: report of 2 cases with burkitt lymphoma-type chromosomal translocations involving c-myc.CONTEXT: The molecular genetic events involved in the pathogenesis of mature B-cell leukemias with more than 55% prolymphocytes are not well characterized. We have encountered 2 such cases in which conventional cytogenetic analysis identified burkitt lymphoma-type chromosomal translocations involving 8q24. OBJECTIVE: To assess these 2 cases for involvement of the c-myc gene using fluorescence in situ hybridization analysis with probes specific for the c-myc and immunoglobulin heavy-chain (IgH) genes. RESULTS: In both cases, conventional cytogenetic analysis demonstrated complex karyotypes, including chromosomal translocations involving 8q24. In case 1, a case of de novo prolymphocytic leukemia, the t(8;14)(q24;q32) was detected. In case 2, a case of chronic lymphocytic leukemia in prolymphocytoid transformation, the t(8;22)(q24;q11) was identified. fluorescence in situ hybridization studies showed c-myc/IgH fusion signals in case 1, proving the presence of the t(8;14). Split c-myc signals without fusion to IgH were observed in case 2, proving c-myc gene rearrangement and consistent with the t(8;22). CONCLUSION: These results suggest that c-myc gene alterations may be involved in the pathogenesis of a subset of mature B-cell leukemias with more than 55% prolymphocytes.- - - - - - - - - - ranking = 2keywords = hybridization (Clic here for more details about this article) |
7/36. Epstein-Barr virus-associated primary B-cell lymphoproliferative disorder of the cerebellum in an immune competent man.BACKGROUND. The role of the Epstein-Barr virus (EBV) in lymphoproliferative lesions has been widely accepted. Most of these lesions occur in patients who have deficiencies in their immune status. lymphomatoid granulomatosis (LG) is a lymphoproliferative disorder originally characterized as an angiocentric, necrotizing, pleomorphic infiltrate of mononuclear cells. The etiology of LG is unknown. It was originally hypothesized that LG may represent an unusual lymphoid response to an infective organism, possibly EBV. methods. tissues from a previously healthy 60-year-old, healthy white man with primary cerebellar lymphomatoid granulomatosis were examined for the presence of EBV by nucleic acid hybridization. RESULTS. The original LG lesion was a polyclonal B-cell proliferation that contained detectable amounts of EBV. Peripheral blood leukocytes were negative for EBV by the same assay. After an 18-month remission, a tumor reappeared near the site of the primary lesion, which had the histologic appearance of a lymphoma. The cells showed restricted clonality and contained a similar amount of EBV-related dna as the original lesion. Peripheral blood leukocytes at the time of recurrence were negative for EBV. The patient died approximately 2 months after the recurrent tumor was detected. CONCLUSIONS. This case demonstrated the development of a primary cerebellar B-cell lymphoproliferative disorder, histologically identical to lymphomatoid granulomatosis, that transformed into a lymphoma. The original tumor and the subsequent lymphoma contained, on average, several copies of EBV-related dna per cell. Despite an extensive survey of the patient, no immune deficit was detected. Interpretation of the literature with the results of this case suggest that this instance of primary cerebellar LG arose as a consequence of an unusual EBV-associated B-cell lymphoproliferation. It is suggested that EBV may be a significant factor in the initiation of the abnormal proliferations of T-cells or B-cells reported in this disorder.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
8/36. enteropathy-associated t-cell lymphoma in a renal transplant patient with evidence of Epstein-Barr virus involvement.The clinical and histological findings in a 54-year-old patient with enteropathy-associated t-cell lymphoma (EATL) occurring 18 years after renal transplantation are presented. Ten years after adult-onset coeliac disease the patient developed medium to large T-cell non-Hodgkin's lymphoma of the small intestine. Epstein-Barr virus (EBV) genome was detected by polymerase chain reaction in the lymphoma tissue and localized via Epstein-Barr virus RNAs in situ hybridization to some of the tumour cells. This is the first case report of EBV-positive EATL occurring in the setting of immunosuppression.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
9/36. Benign lymphocytic angiitis and granulomatosis: a T-cell lymphoma?Benign lymphocytic angiitis and granulomatosis is a T-cell lymphoproliferative disorder confined to the lung and corresponding to a low-grade angiocentric immunoproliferative lesion. Controversy remains as to whether these lesions are lymphomas. We report such a case in an 8-year-old patient with Burkitt's lymphoma in remission who presented with persistent bronchopneumopathy and bilateral pulmonary infiltrates on tomodensitometry. Surgical resection revealed the histologic changes of benign lymphocytic angiitis and granulomatosis. immunohistochemistry showed no aberrant pan T-cell marker loss. Genetic analysis of frozen tissue by Southern blot dna hybridization with probes to T-cell receptor beta- and gamma-chain genes and to the immunoglobulin heavy chain joining region gene (JH) identified no clonal rearrangement. Search for Epstein-Barr virus-dna sequences by in situ hybridization and Southern blot analysis provided negative results. Our data imply that lowgrade angiocentric immunoproliferative lesions are not exclusively lymphomas but might represent a borderline lymphoproliferative disease (seen in the course of many diseases), perhaps corresponding to host immune response.- - - - - - - - - - ranking = 2keywords = hybridization (Clic here for more details about this article) |
10/36. Is B-lineage acute lymphoblastic leukemia with a mature phenotype and l1 morphology a precursor B-lymphoblastic leukemia/lymphoma or Burkitt leukemia/lymphoma?CONTEXT: B-lineage acute lymphoblastic leukemia (ALL) with a mature phenotype and L1 morphology is a rare condition that may pose a diagnostic and management challenge. OBJECTIVE: To report our experience with 2 such unusual cases of pediatric B-lineage ALL. DESIGN: Morphologic, immunophenotypic, and cytogenetic features of the leukemic blast cells were reviewed in conjunction with clinical and other laboratory findings. RESULTS: The leukemic blast cells in both cases were small to medium with scant basophilic cytoplasm and several small inconspicuous nucleoli, characteristic of L1 lymphoblasts. Immunophenotypically, they were positive for CD19, CD22, and low-density CD20, with expression of surface immunoglobulin lambda light chain. They were negative for immature (CD34 and terminal deoxynucleotidyl transferase), myeloid, and T-cell-associated markers. Conventional cytogenetic and fluorescent in situ hybridization studies failed to demonstrate chromosomal translocations involving the c-myc gene. Both patients were treated with Children's Cancer Group ALL protocols and had good responses. CONCLUSIONS: B-lineage ALL with a mature phenotype, L1 morphology, and absent chromosomal translocations involving the c-myc gene is best classified and managed as precursor B-lymphoblastic leukemia/lymphoma instead of Burkitt leukemia/lymphoma.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
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