1/38. trisomy 9 in a patient with secondary acute myelogenous leukemia detected by fluorescent in situ hybridization.Fluorescent in situ hybridization (FISH) is a molecular cytogenetic technique that is playing an increasingly important role for augmenting the findings of conventional cytogenetics. Here we present the case history of a patient with the clinical diagnosis of secondary acute myelogenous leukemia whose bone marrow cells were found to be hyperdiploid with an extra C group chromosome in a less than optimal preparation. By using FISH the extra chromosome was unequivocally determined to be a chromosome 9. The detection of trisomy 9 in this patient underscores the utility of FISH as an adjunct to GTG banding in the routine diagnosis and management of leukemic patients.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/38. Classical Hodgkin's disease and follicular lymphoma originating from the same germinal center B cell.PURPOSE: Classical Hodgkin's disease and non-Hodgkin's B-cell lymphoma occasionally occur in the same patient. To clarify whether these different diseases share a common precursor cell, we analyzed the immunoglobulin rearrangements in tumor cells of the classical Hodgkin's disease and the follicular lymphoma that developed in the same patient 2 years apart. patients AND methods: polymerase chain reaction (PCR) for the detection of rearranged immunoglobulin genes was carried out on single reed-sternberg cells and on whole tissue dna extracted from the follicular lymphoma. PCR products were sequenced and compared with each other and with germ line immunoglobulin variable segments. Immunoglobulin heavy- and light-chain transcripts were analyzed by radioactive in-situ hybridization. RESULTS: The same monoclonal immunoglobulin gene rearrangement was found in both neoplasms. The variable region of the immunoglobulin heavy-chain genes of the Reed-Sternberg and of the follicular lymphoma cells were differently mutated, but six somatic mutations were shared by both lymphoma cells. Although the coding capacity of the immunoglobulin genes was preserved in both neoplastic cell populations, immunoglobulin heavy- (mu) and light- (kappa) chain expression was restricted to the follicular lymphoma cells, except for small amounts of kappa light-chain mRNA in some reed-sternberg cells. CONCLUSIONS: The neoplastic cells of the Hodgkin's disease and the follicular lymphoma that occurred in this patient derived from a common precursor B cell. Its differentiation stage could be identified as that of a germinal center B cell. Thus, transforming events can be more important than the cell of origin in determining a disease entity.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
3/38. Morphologically normal, CD30-negative b-lymphocytes with chromosome aberrations in classical Hodgkin's disease: the progenitor cell of the malignant clone?A recent study observed that numerical chromosome abnormalities in Hodgkin's disease (HD) are detected not only in morphologically abnormal Hodgkin/reed-sternberg cells, but also in a fraction of morphologically normal cells. However, the phenotypic constitution of these genetically abnormal, morphologically normal cells and their relationship to the malignant Hodgkin/reed-sternberg cells could not be established in the earlier cases studied, because of the low frequency of these cells. The present study investigated two cases of classical Hodgkin's disease containing a relatively large population of such apparently normal cells with aberrant chromosome copy numbers. The phenotype and their position within the developmental route of the malignant compartment were examined by a combined in situ hybridization and immunocytochemistry approach. Numerical abnormalities for chromosome 1 in one case and for chromosomes X, Y, and 1 in the other case were observed not only in CD30-positive Hodgkin/reed-sternberg cells, but also in CD30-negative, morphologically normal cells. It was shown that these genetically aberrant cells expressed the B-cell antigen CD19, thus confirming their B-cell nature. These studies indicate a relationship between the genome aberrations in these genetically abnormal, morphologically normal B-cells and the Hodgkin/reed-sternberg cells, suggesting that they are progenitor cells of the malignant cell fraction.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
4/38. A real-time PCR assay for the quantification of residual malignant cells in B cell chronic lymphatic leukemia.Several new therapeutic approaches for the treatment of monoclonal B cell lymphomas are currently being investigated. In parallel with new therapeutic modalities, more sensitive diagnostic methods are needed. These methods should be highly sensitive in detecting very low amounts of malignant cells and should be specific for the malignant clone. In addition, these methods should allow the quantification of residual tumor cells. In this study a new real-time polymerase chain reaction (LightCycler) was evaluated to quantify residual tumor cells in monoclonal B cell malignancies. This technology combines the advantages of rapid cycling PCR with the online detection of PCR products using fluorescent dyes. Our assay is based on immunoglobulin heavy chain (IgVH)-specific PCR with allele-specific primers complementary to hypervariable CDRII and CDRIII regions. A set of framework region III (FRIII)-specific hybridization probes was used for detection of the specific amplification product, and IgVH copy number was quantified with the cloned IgVH sequence as an external standard. The approach was evaluated with the Hodgkin lymphoma cell line L428 in order to quantify L428 dilutions. L428 cells mixed with peripheral blood mononuclear cells (PBMNCs) were detected and quantified with a sensitivity of one cell within 1 x 10(5) PBMNCs. Sample dna from the peripheral blood and from the bone marrow of two patients with B-CLL was analyzed in the new set up at different time points before and after therapy. Statistically significant changes in IgVH copy numbers were documented in both patients. We conclude that this technology offers an additional opportunity to detect and quantify residual tumor cells in B-CLL over several log steps with a high sensitivity. The kinetics of residual tumor cell counts in B-CLL can be analyzed by this method.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
5/38. Hodgkin's disease and peripheral T-cell lymphoma: composite lymphoma with evidence of Epstein-Barr virus infection.This paper reports the case of a patient with a composite lymphoma consisting of nodular sclerosing Hodgkin's disease and peripheral T-cell lymphoma. The Hodgkin and Reed-Sternberg (HRS) cells harboured the Epstein-Barr virus (EBV) and displayed a type II EBV latency (LMP1( )/EBNA2(-)), whereas the neoplastic T-cells were EBV-negative. Four years later, the patient presented with a relapse of the peripheral T-cell lymphoma. in situ hybridization revealed numerous EBV-carrying lymphocytes, which were shown to be polyclonal B-cells with a latency III pattern of EBV gene expression (LMP1( )/EBNA2( )). This observation suggests that impairment of EBV-specific immunity in the micro-environment of T-cell lymphomas may facilitate the outgrowth of EBV-carrying b-lymphocytes and emphasizes the importance of determining the phenotype of EBV-infected cells, particularly when studying T-cell lymphomas. The results further suggest that the HRS cells and neoplastic T-cells were of different clonal origins. The detection of EBV-carrying cell populations admixed with the neoplastic T-cells at primary presentation and at relapse raises the possibility that the growth of the T-cell lymphoma was dependent on the presence of such cells.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
6/38. Nonrandom rearrangements of 6p in malignant hematological disorders.It is very uncommon to observe nontranslocation abnormalities (NTAs) involving the short arm of chromosome 6 (6p) in malignant hematological disorders (MHDs). By using conventional cytogenetics and fluorescence in situ hybridization (FISH) with chromosome-microdissection probes specific for 6p21 and 6p25, we observed five patients with myeloid malignancies and two patients with lymphoid malignancies to have 6p NTAs. On the basis of our data and those in the literature, it is possible to divide 6p NTAs into the following three groups in MHD: The first group presents with 6p NTAs as a sole or primary change in myeloid malignancies. There are only two cases reported in this group, including one case with del(6)(p23) and the present case with ins(6)(q23p23p25) identified by FISH only. The second group presents with 6p deletions as a sole or primary change in lymphoid malignancies. Three cases have been reported in this group, including one case with del(6)(p21p23), one with del(6)(p21), and the present case 2 with del(6)(p21). The third group has 6p deletions in addition to other known primary changes, present in both myeloid and lymphoid disorders, with 36 cases reported, including five cases from our series. Deletions involving 6p21, 6p22, or 6p23 have been observed in both myeloid and lymphoid disorders. The present data provide cogent information for further molecular characterization of 6p anomalies in MHD.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
7/38. Detection of t(14; 18)(q32;q21) in hyperdiploid cells by fluorescence in situ hybridization in a patient with hodgkin disease.The most frequent nonrandom chromosome rearrangements in B-cell non-Hodgkin lymphoma (NHL) is the t(14;18)(q32;q21) found in follicular lymphomas. The t(14;18) in hodgkin disease (HD) was rarely observed using cytogenetic techniques. Although Southern blot analysis failed to demonstrate the t(14;18), there have been conflicting reports concerning the occurrence of the translocation using polymerase chain reaction (PCR) methods in HD. In some HD tissues, the translocation might be derived from background lymphocytes rather than Hodgkin and Reed-Sternberg (HRS) cells, because B-cells with t(14;18) are regularly generated in normal individuals. However, the cells bearing the translocation have remained unidentified. We describe a patient with HD who showed t(14;18) in hyperdiploid cells using fluorescence in situ hybridization (FISH) and HRS cells which were strongly positive for BCL2 by immunohistochemistry. These findings suggest that HRS cells may have a t(14;18).- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
8/38. Epstein-Barr virus-negative Hodgkin's lymphoma after mycosis fungoides: molecular evidence for distinct clonal origin.The association of mycosis fungoides (MF) and Hodgkin's lymphoma is a relatively frequent occurrence, but the potential clonal relationship of the two neoplasms is still controversial. We report a case of a patient with a history of MF in Clinical Stage 1A who developed retroperitoneal lymphadenopathy 9 years after the initial diagnosis of MF. A bone marrow biopsy obtained at this time showed nodular involvement by a mixed cellular infiltrate with large, atypical cells consistent with Hodgkin and Reed-Sternberg (RS) cells. These atypical cells were positive for CD30 and CD15 and did not express B- or T-cell markers. In addition, they lacked evidence of infection by Epstein-Barr virus, both by immunohistochemical staining for latent membrane protein 1 and by in situ hybridization for EBER1/2. The background population consisted mainly of small T cells without morphological or phenotypical signs of malignancy. review of the skin biopsy obtained 9 years before showed the typical features of MF. polymerase chain reaction analysis of the T-cell receptor T-gene confirmed the presence of a clonal T-cell rearrangement in the skin specimen. The bone marrow biopsy, however, showed a polyclonal pattern both for the T-cell receptor gamma-gene, as well as for immunoglobulin heavy chain genes. Isolation of RS cells stained for CD30 was performed by laser capture microdissection. polymerase chain reaction analysis of several groups of RS cells showed a reproducible biallelic rearrangement of IgH genes, which was confirmed by cloning and sequencing of polymerase chain reaction products. To our knowledge, this is the first case in which a distinct clonal origin of MF and Hodgkin's lymphoma arising in the same patient is clearly demonstrated, based on molecular analysis of microdissected RS cells.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
9/38. The NPM-ALK and the ATIC-ALK fusion genes can be detected in non-neoplastic cells.Anaplastic large cell lymphoma (ALCL) is frequently associated with the t(2;5)(p23;q35) translocation. It creates a NPM-ALK fusion gene, fusing the anaplastic lymphoma kinase (ALK) gene (2p23) and the nucleophosmin (NPM) gene (5q35). Other rearrangements involving the ALK gene have recently been shown to be associated with ALCL, among which the ATIC-ALK rearrangement resulting from the inv(2)(p23q35) translocation is probably the most recurrent. The aims of the present study were to investigate the presence of NPM-ALK and ATIC-ALK fusion genes in ALCL, using a real-time 5' exonuclease-based reverse-transcription polymerase chain reaction (RT-PCR). This sensitive technique was also applied to investigate whether both fusion genes might be detected in Hodgkin's disease cases and in reactive lymphoid tissue. Results of the RT-PCR were compared to ALK immunostaining, cytogenetics, and fluorescence in situ hybridization (FISH) results. RT-PCR detected the NPM-ALK and ATIC-ALK fusions at high levels in 8 and 3 of a total of 13 ALK-positive ALCL cases. One ALK-positive ALCL case was negative for both fusion genes analyzed but revealed a new ALK-related translocation t(2;17)(p23;q25) by cytogenetic and FISH analysis. In addition, of the eight ALK-positive ALCL cases that were strongly positive for the NPM-ALK fusion, three cases also showed the presence of the ATIC-ALK fusion, although at much lower levels. Similarly, out of the three strongly positive ATIC-ALK cases, one case was positive for the NPM-ALK fusion, at low levels. Finally, the NPM-ALK and the ATIC-ALK fusions were detected, at equally low levels, respectively in 13 and 5 ALK-negative ALCL cases, in 11 and 5 Hodgkin's disease cases and in 20 and 1 non-neoplastic lymphoid tissues. The distinction between the high- and low-level detection was confirmed by relative quantitative RT-PCR for a representative number of cases. Of interest is the fact that the high-level detection coincided with the presence of ALK gene rearrangement detected by cytogenetics and FISH and may reflect a central role of the transcript in the oncogenic mechanism of ALK-positive ALCL. Low-level detection is not supported by cytogenetics and FISH, presumably due to the presence of the transcripts in only a small minority of normal cells not detectable by these techniques. Our findings demonstrate that NPM-ALK and ATIC-ALK fusion transcripts may be detected in conditions other than ALK-positive ALCL including reactive lymphoid tissues, although at low levels, suggesting the presence of the transcripts in normal (bystander) cells. Moreover, they suggest that the ALK gene rearrangement by itself might be insufficient to induce tumor formation. They further question the validity of quantitative real-time RT-PCR for monitoring minimal residual disease in ALCL. Finally, the newly identified translocation t(2;17)(p23;q25) can be added to the list of ALK gene rearrangements occurring in ALK-positive ALCL.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
10/38. EBV-associated Hodgkin's disease in an hiv-infected child presenting with a hemophagocytic syndrome.An 8-years-old boy was admitted with fever of unknown origin, cervical lymphadenopathy and hepatosplenomegaly and weight loss. His mother's hiv infection was diagnosed two weeks before his hospitalization, so he was diagnosed as perinatally acquired AIDS. serology and serial cultures were negative for viral infections, toxoplasmosis, chagas, tuberculosis and atypical mycobacterium. The patient met clinical and laboratory criteria for hemophagocytic syndrome (HS) that was confirmed on bone marrow aspirate and biopsy. A cervical lymph node biopsy was performed which was diagnosed as Hodgkin's disease (HD) diffuse fibrosis lymphocyte depletion subtype. EBERs in situ hybridization and LMP-1 immunohistochemistry on the lymph node biopsy established the EBV association. On the basis of a sequence of appearance of the clinical, laboratory and histological signs, hiv, EBV or HD may have triggered HS as the last fatal event in this pediatric patient.- - - - - - - - - - ranking = 0.2keywords = hybridization (Clic here for more details about this article) |
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