1/6. Common germinal-center B-cell origin of the malignant cells in two composite lymphomas, involving classical Hodgkin's disease and either follicular lymphoma or B-CLL.BACKGROUND: Classical Hodgkin's disease (HD) and B-cell non-Hodgkin lymphoma (NHL) occasionally occur in the same patient. Such composite lymphomas represent interesting models to study the pathogenesis of B-cell lymphomas and the relationship between HD and B-cell NHL. MATERIALS AND methods: We analyzed two composite lymphomas (a combination of classical HD with follicular lymphoma [FL] and a combination of classical HD with B-cell chronic lymphocytic leukemia [B-CLL]) by micromanipulation of single cells from tissue sections and amplification of immunoglobulin V region genes for the clonal relationship of the tumor cells. RESULTS: In both cases, clonally related variable (V) genes with both shared as well as distinct somatic mutations were obtained from the two lymphomas, showing that in each of the cases the distinct tumor cells were members of a common germinal center (GC) B-cell clone. FL cells from two different lymph nodes of patient 1 showed a similar mutation pattern, suggesting that infiltration of these lymph nodes by tumor cells was not restricted to a particular FL cell or subclone. In the FL, a single cell was identified with a mutation signature indicating that premalignant cells can persist in the tissue. CONCLUSIONS: The cases presented here further underline the close relationship between HD and B-cell NHL and the role of the GC in lymphomagenesis. Whereas the latter was already suggested for FL and HD, the present study indicates that also in the B-CLL subset characterized by mutated Ig genes, important steps in malignant transformation happen in the GC, and that HRS cells can derive from CD5-positive B cells.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
2/6. B-Prolymphocytic leukemia: a case study.The case study reported is of a patient initially misdiagnosed as chronic lymphocytic leukemia. immunophenotyping studies ultimately identified the nature of the disease as B-cell prolymphocytic leukemia with concomitant warm autoimmune hemolytic anemia. The leukemia and hemolytic anemia were refractory to all conventional treatments administered. The patient survived a significantly shorter period of time than the median time of three years reported in the literature. The patient expired from complications resulting from B-cell PLL, warm autoimmune hemolytic anemia, and combination chemotherapy.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
3/6. Unusual case of leukemic mantle cell lymphoma with amplified CCND1/IGH fusion gene.We describe a case of leukemic mantle cell lymphoma (MCL) with complex karyotype and amplification of the CCND1/IGH fusion gene. Testing for the presence of t(11;14), the hallmark of MCL, revealed multiple copies of the fusion signals. We therefore conducted extensive molecular cytogenetic studies to delineate the nature and consequences of such an abnormality. We localized the amplification to the der(14)t(11;14) and to a der(2) chromosome in a form of interspersed chromosome 11 and 14 material. This resulted in high expression of cyclin d1 mRNA and the protein expressed independently of the cell cycle phase. CGH analysis revealed that the overrepresentation on chromosome 11 included chromosomal band 11q23 in addition to the CCND1 locus at 11q13. The band 11q23 harbors the ataxia telangiectasia mutated (ATM) gene recently proposed to be involved in the pathogenesis of MCL with high incidence of deletions in this locus. Using YAC 801e11, containing the ATM gene, we demonstrated several hybridization signals, suggesting that this region also formed part of the amplicon. This case also showed TP53 gene abnormalities: protein expression, monoallelic deletion, and a mutation in exon 5. The clinical course was aggressive, and the patient died within 6 months of presentation. This is to our knowledge the first description of amplification of the CCND1/IGH fusion gene in a human neoplasm, which may have played a role in the fulminating course of the disease in this patient.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
4/6. trisomy 12-associated, t(11;14)-negative mature B-cell leukemia with gene expression profile resembling mantle cell lymphoma.trisomy 12 can be seen in many different lymphoid neoplasms. However, many or most mature B-cell leukemias associated with isolated trisomy 12 are reported in the literature as chronic lymphocytic leukemia (CLL) or 'atypical CLL'. This study reports a case of a mature B-cell leukemia, morphologically and immunophenotypically similar to cases previously published as atypical CLL, in which cytogenetic evaluation revealed an isolated clonal trisomy 12 but no evidence of the mantle cell lymphoma-associated t(11;14)(q13;q32). Further analysis confirmed absence of cyclin-D1 expression. Subsequent lymph node biopsy revealed evidence of large cell transformation of the underlying chronic lymphoproliferative disorder. gene expression profiling of the initial peripheral blood sample using a cDNA micro-array of approximately 10,000 expressed genes revealed a close resemblance between the reported case and 2 cases of known mantle cell lymphoma. When further compared to 7 known 'typical' CLL cases, the reported case was classified as mantle cell lymphoma by hierarchical cluster analysis. The case reported here raises interesting questions regarding the nature of cases reported previously as trisomy 12-associated CLL and reinforces the fact that other leukemic lymphoproliferative disorders should be included in the differential diagnosis of such cases. Further study is indicated to elucidate the nature and diversity of disorders previously reported as trisomy 12-associated chronic lymphocytic leukemia.- - - - - - - - - - ranking = 2keywords = nature (Clic here for more details about this article) |
5/6. B-cell malignancy after low grade T-cell lymphoma.BACKGROUND. Low grade, small lymphocytic, non-Hodgkin's lymphoma, was diagnosed in a 38-year-old woman. Thirty months after the initial diagnosis was made, a population of lymphoid cells with pathologic morphology was found in the patient's peripheral blood (PB). Cell phenotyping was performed and monoclonality was analyzed in cells obtained from a removed lymph node (LN) and the PB of the patient. methods. The cell phenotype was examined with immunofluorescence techniques using antibodies against SIg and monoclonal antibodies against CD1, CD3, CD4, CD5, CD8, CD19, and the kappa, and lambda light chains. gene rearrangement analysis for monoclonality determination was performed with restricted dna (EcoRI, Hin-dIII and BamHI) hybridized with either 32P-labeled T-cell receptor dna probe (TcR-beta) or immunoglobulin-heavy chain probe (JH). RESULTS. With regard to the cell population of the removed LN, cell phenotyping showed the predominance of CD4 T-cells over a polyclonal B-cell population. gene rearrangement analysis proved the monoclonal nature of the T-cells and the polyclonal nature of the B-cells. As to the PB, gene rearrangement and cell phenotyping of the lymphocytes showed the predominance of monoclonal kappa type B-cells over polyclonal T-cells. CONCLUSIONS. The data obtained suggest two unrelated lymphoproliferative diseases in this patient, expressed as monoclonal T-cell population in LN and as monoclonal B-cell population in PB.- - - - - - - - - - ranking = 2keywords = nature (Clic here for more details about this article) |
6/6. Leukemic meningitis in a patient with splenic lymphoma with villous lymphocytes (SLVL). meningitis as a possible initial manifestation of SLVL.BACKGROUND. Splenic lymphoma with villous lymphocytes (SLVL) is a low grade, non-Hodgkin's lymphoma with a stable or slowly progressive clinical course. To the authors' knowledge, central nervous system involvement has not been described previously in patients with SLVL. methods. Morphologic, immunocytochemical, and immunohistochemical analyses were conducted to determine the nature of villous lymphocytes in the peripheral blood, spleen, and cerebrospinal fluid (CSF) of a patient with massive splenomegaly. RESULTS. A diagnosis of SLVL was made, based on tartrate-resistant acid phosphatase-negative peripheral villous lymphocytosis with CD19 , CD20 , HLA-DR phenotypes, and the involvement of spleen white pulp with these cells. Mononuclear cells in the CSF showed the same morphologic and immunocytochemical features seen in the villous lymphocytes in the peripheral blood and spleen. splenectomy and intrathecal chemotherapy were successful in clearing leukemic cells from the CSF. CONCLUSION. In this patient with SLVL in whom leukemic meningitis developed, meningitis was found to be a possible initial manifestation of SLVL.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |