1/41. CD56 lymphoma presenting as a testicular tumor.A case of an unusual lymphoma type, CD56 ( ) T/NK lymphoma, presenting as a testicular tumor is described. A 35 year old man who presented with right testicular swelling, underwent right inguinal orchiectomy, with a presumptive diagnosis of abscess or malignancy. Histopathology showed a diffuse mixed large and small cell lymphoma with a focal angiocentric growth pattern. Immunohistochemically CD45RO and CD56 were found to be positive in the neoplastic cells. in situ hybridization assay for EBV showed the presence of EBV related small ribonucleic acid sequences (EBER) within the tumor cells. Despite systemic chemotherapy, the patient had an aggressive clinical course with two skin and left testicular recurrences in the first year of his disease.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/41. Ph-negative non-Hodgkin's lymphoma occurring in chronic phase of Ph-positive chronic myelogenous leukemia is defined as a genetically different neoplasm from extramedullary localized blast crisis: report of two cases and review of the literature.This report describes two cases of philadelphia chromosome-negative (Ph(-)) non-Hodgkin's lymphomas (NHLs) recognized in patients with chronic phase Ph-positive (Ph( )) chronic myelogenous leukemia (CML). Lymph node biopsy of patient 1 was initially diagnosed as diffuse large B cell non-Hodgkin's lymphoma (NHL, T cell rich variant), but at relapse showed immunoblastic features with a marked decrease of admixed lymphocyte components. Patient 2 presented with thickened parietal pleura which revealed a CD30-positive anaplastic large cell lymphoma showing null cell phenotype and genotype with abundant admixed neutrophils and lymphocytes. At the time of lymphoma diagnosis, the patients had CML for 33 and 10 months, respectively. dna obtained from bone marrow cells at the time of lymphoma diagnosis showed BCR/ABL gene rearrangements by both Southern blot analysis and reverse transcription polymerase chain reaction (RT-PCR), but lacked both immunoglobulin and T cell receptor gene rearrangements. BCR gene rearrangement and BCR/ABL fusion gene were also identified in lymph node and pleural biopsies by Southern blot and RT-PCR analysis, respectively. However, both biopsy specimens also contained reactive lymphocytes and neutrophils, and no fusion signals between BCR and ABL genes were identified in the hyperdiploid lymphoma cells of either case by fluorescence in situ hybridization (FISH). These data suggest the lymphoma cells in both cases were not genetically associated with BCR/ABL. Therefore, these cases were not diagnosed as an extramedullary localized blast crisis in CML, but as Ph(-) NHLs. This represents the first definitive demonstration of peripheral B cell lymphoma occurring by a separate genetic pathway, lacking BCR/ABL, in patients with Ph( ) CML. A review of the literature identified two different subtypes of malignant lymphomas arising in patients with an antecedent or concurrent diagnosis of CML. The most common are T cell lymphomas displaying an immature thymic phenotype, while peripheral B cell lymphomas are more rare. Our study shows, however, that 'Ph( ) NHL' occurring in CML or acute lymphocytic leukemia (ALL) may represent an unrelated neoplasm, even if standard cytogenetic analysis reveals a Ph( ) chromosome, and that FISH is required to confirm whether a localized lymphoid neoplasm is either a true extramedullary localized blast crisis or genetically distinct neoplasm. leukemia(2000) 14, 169-182.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/41. New chromosomal breakpoints in non-Hodgkin's lymphomas revealed by spectral karyotyping and G-banding.Chromosomal rearrangements in short term cultures from nine cases of non-Hodgkin's lymphomas (NHL) were characterized by G-banding, spectral karyotyping (SKY), and fluorescence in situ hybridization (FISH). Eight of the nine cases showed complex karyotypes with chromosomal aberrations which, in most cases, could not be fully characterized by traditional G-banding analysis alone. Karyotypic abnormalities of special interest were marker chromosomes and chromosomes with added unidentified chromosomal material, as previously non-identified chromosomal translocations were hidden behind these aberrations. SKY and FISH analysis, as a complement to banding analysis, significantly improved the karyotypes in seven of the nine cases and unveiled 21 previously unidentified rearrangements with novel translocation breakpoints. Traditional G-banding alone revealed seven new rearrangements, which were all confirmed by SKY. None of these new aberrations occurred as single clonal rearrangements but as parts of complex karyotypes. Nevertheless, the chromosomal break-point regions identified should be considered as potential hot spots for genes involved in the tumorigenesis of the malignancy.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/41. Post-transplant lymphoproliferative disorders (PTLD) after renal transplantation: management and evolution of seven cases among 1002 renal transplants in Sao Paulo, brazil.We reported seven cases (0.7%) of PTLD among 1002 renal transplants performed at Renal Transplant Service from Hospital Sao Paulo-Universidade Federal de Sao Paulo/Escola Paulista de Medicina, Sao Paulo, brazil, between 1976 and 1997. There were three male and four female patients with median age of 37 year-old. According to Ann Arbor staging system there were four localized extra-nodal intermediate-grade NHL, one disseminated low-grade NHL and two polyclonal lymphoid hyperplasia. Four patients received cadaveric, two received related and one received unrelated renal transplant. PTLD occurred after a median latency period of 36 months (ranging from 5 to 84 months). in situ hybridization for EBER1 was performed in five patients and molecular evidence of EBV was found in 3 cases (two DLCL and one lymphoplasmocytoid lymphoma). All patients were treated with immunosuppression withdrawal, four patients received anthracyclin-based chemotherapy for control of localized or systemic clonal disease and three were treated with resection of primary PTLD. Four of seven patients (57%) are in complete remission 11, 20, 25 and 79 months after PTLD onset. One patient lost follow-up and two patients died due to lymphoma relapse, respectively 4 and 10 months after completion of treatment. In conclusion, our experience with this small group of patients showed that: 1) immunosuppression withdrawal is not necessarily associated with loss of renal transplant and can be used as the only treatment for polyclonal PTLD; 2) chemotherapy can simultaneously lead to clonal PTLD remission and periodic immunosuppression, avoiding graft rejection after immunosuppression withdrawal.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/41. Translocation t(2;7)(p12;q21-22) with dysregulation of the CDK6 gene mapping to 7q21-22 in a non-Hodgkin's lymphoma with leukemia.BACKGROUND AND OBJECTIVES: A female patient presented with splenomegaly and lymphocytosis with atypical lymphoid cell morphology. We identified t(2;7)(p12;q21) prompting studies of the translocation breakpoint and its consequences on protein expression to confirm or otherwise the recently reported involvement of CDK6 and IG k genes in the t(2;7) leading to over-expression of CDK6 protein. DESIGN AND methods: A variety of clinical and laboratory techniques including cell marker, cytogenetic and histologic studies were applied in order to establish the diagnosis. fluorescence in situ hybridization (FISH) and Southern blotting were used for mapping the translocation breakpoint and Western blotting for assessing protein expression. RESULTS: immunophenotyping showed the presence of a B-cell population with strong expression of FMC7, CD22, CD79b, CD5 and k restricted surface immunoglobulins. Based on morphology and immunophenotypic markers the diagnosis of B-cell non-Hodgkin's lymphoma was made. Karyotyping revealed a clone with t(2;7)(p12;q21-22). Evidence for clonal evolution with additional abnormalities including a deletion of the TP53 was present. We established by FISH and Southern blotting that the breakpoint on 7q21-22 fell in a region 66kb telomeric to the previously reported breakpoint for the t(2;7) and was the same as that observed in a t(7;21). CDK6 protein was over-expressed. The patient received alkylating agents and splenectomy and is alive but the lymphocytosis persists with evidence of disease progression. INTERPRETATIONS AND CONCLUSIONS: We have demonstrated that CDK6 expression is dysregulated even when the breakpoint on 7q21-22 is located 66kb upstream from the coding region. Interestingly, the precise assignment of the lymphoma type in our case was not possible even when the splenic histology was analyzed.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
6/41. Unusual karyotype aberrations involving 2p12, 3q27, 18q21, 8q24, and 14q32 in a patient with non-Hodgkin lymphoma/acute lymphoblastic leukemia.The t(2;18)(p12;q21), known as a rare variant of the t(14;18)(q32;q21), together with t(3;14)(q27;q32), t(8;15)(q24;q22) and two other unusual translocations involving chromosomes 6, 9, 12, and 13, were demonstrated in the bone marrow cells of a 70-year-old male with suspected non-Hodgkin lymphoma/acute lymphoblastic leukemia. The complex chromosomal aberrations were identified by chromosome banding analysis and by fluorescence in situ hybridization (FISH) with whole chromosome painting probes, centromere-specific alpha-satellite probes, and probes specific for genomic sequences of some likely to be involved candidate genes. Several but not all of the chromosomal aberrations could be proved by multicolor FISH. Possible mechanisms leading to this unusual karyotype commonly associated with different histologic lymphoma subtypes and their prognostic implications are discussed.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
7/41. Spontaneous remission of Epstein-Barr virus-negative non-Hodgkin's lymphoma after withdrawal of cyclosporine in a patient with refractory anemia.A 70-year-old man presented with pancytopenia in August 2000, and the results of a bone marrow examination performed in January 2001 confirmed the diagnosis of refractory anemia. He was treated with cyclosporine (CsA) at 3.3 mg/kg per day, and the pancytopenia improved. The patient complained of epigastralgia 21 months later, and a gastric endoscopic examination showed an ulcer with a cleaved bank. A biopsy revealed diffuse large B-cell lymphoma. in situ hybridization analysis detected no Epstein-Barr virus (EBV) in the lymphoma. CsA treatment was discontinued, and a gastrectomy was performed 31 days later. A detailed histologic examination revealed no infiltration of abnormal B-cells in the resected stomach. Although EBV-positive lymphoma is a known complication of immunosuppressive therapy, no causal association between immunosuppressants and EBV-negative lymphoma has been established. The spontaneous remission observed after the withdrawal of CsA treatment suggests that immunosuppressive therapy can be a pathogenic factor in a subset of EBV-negative lymphomas.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
8/41. Blastic natural killer (NK)-cell lymphoma: report of an unusual CD4 negative case and review of the CD4 negative neoplasms with blastic features in the literature.Blastic Natural Killer (NK)-cell lymphoma is a relatively new entity which has been recently included in the WHO classification. CD4 expression is observed in most cases of blastic NK-cell lymphomas and has been related with skin tropism. We report an unusual CD4 negative blastic NK-cell lymphoma with primary presentation in the skin, subsequent infiltration of the bone marrow and aggressive behavior. It is emphasized that extensive immunophenotyping and EBER rna in situ hybridization are required in order to establish the diagnosis of blastic NK-cell lymphoma. We also present a review of the literature with respect to the CD4 negative NK-cell lymphomas with blastic morphological features.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
9/41. Aggressive forms of non-Hodgkin's lymphoma in two patients bearing coinfection of Epstein-Barr and hepatitis c viruses.Although epidemiologic and experimental data suggest an etiopathogenetic role for both hepatitis c virus (HCV) and Epstein-Barr virus (EBV) infection in development of B-cell non-Hodgkin's lymphoma (NHL), potential interactions between EBV and HCV during progression of B-cell NHL have not yet been fully investigated. In the present study, tumor biopsy specimens from patients with both B-cell NHL and chronic HCV infection (HCV( )) were analyzed for the presence of EBV-encoded rna (EBER) by in situ hybridization (ISH). VH and VL gene segments were amplified from tumor biopsy specimen dna by PCR. EBV infection (EBV( )) was detected in tumors from 2 of 31 (6%) HCV( ) B-cell NHL patients. Clinical histories of these two EBV( )/HCV( ) B-cell NHL patients indicated a particularly aggressive course of disease. Chemotherapy failed to induce long lasting remission for either of these EBV( )/HCV( ) B-cell NHL patients. Amplification of CDR3 of the Ig heavy chain gene from dna isolated from each EBV( )/HCV( ) B-cell NHL indicated the presence of monoclonal B-cell expansion. Rearrangement of Ig genes in neoplastic B-cell clones from both EBV( )/HCV( ) patients was similar to that previously reported for EBV(-)/HCV( ) B-cell NHL patients. Additionally, neoplastic B-cell clones from these two EBV( )/HCV( ) B-cell NHL patients did not exhibit intraclonal variation. Previous studies have demonstrated that intraclonal variation is common among neoplastic B-cell clones from EBV(-)/HCV( ) patients. EBV infection may have prevented evolution of variant neoplastic B-cell clones by suppressing antibody affinity maturation. Together, these data suggest that EBV infection may cooperate with HCV infection during progression of B-cell NHL in immunocompetent individuals. Such an interaction may accelerate the course of disease in B-cell NHL patients.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
10/41. Distinguishing between proliferating nodal lymphoid blasts in chronic myelogenous leukemia and non-Hodgkin lymphoma: report of three cases and detection of a bcr/abl fusion signal by single-cell analysis.Lymph node biopsies were analyzed from three patients with chronic myelogenous leukemia (CML) showing nodal blast proliferation. Immunohistochemically, the blasts from all three patients had an immature marker profile with a T-blast population (cCD3 , CD4-, CD7 , CD8-, CD99 , terminal deoxynucleotidyl transferase ) and a hematopoietic progenitor cell marker (CD34). In two patients, the blasts also expressed myeloid lineage specificity (naphthol AS-D chloroacetate esterase activity and myeloperoxidase positivity). However, it was difficult to distinguish between blast proliferation in CML and non-Hodgkin lymphoma from these immunohistopathological findings alone. Subsequently, bcr gene rearrangement and bcr/abl mRNA expression were detected by Southern blot and reverse transcription-polymerase chain reaction analysis of the lymph nodes. fluorescence in situ hybridization (FISH) analysis of lymph node touch smears also disclosed bcr/abl gene fusion signals in the blasts of all patients, confirming that the blasts were derived from philadelphia chromosome-positive CML. Accurate discrimination between the proliferating nodal blasts of CML and non-Hodgkin lymphoma is essential for determining subsequent therapy. FISH analysis of bcr/abl in single-cell blast preparations is an efficient tool that allows rapid, accurate cytopathological diagnosis of extramedullary blast-phase CML and its discrimination from non-Hodgkin lymphoma.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
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