1/45. 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 = 1keywords = hybridization (Clic here for more details about this article) |
2/45. Large cell transformation of sezary syndrome. A conventional and molecular cytogenetic study.Hyperdiploidy sometimes is found in mycosis fungoides-sezary syndrome, but its diagnostic significance remains undefined. We report an unusual case of sezary syndrome manifesting with leukemic large cell transformation. Conventional karyotypic analysis showed the presence of a near-tetraploid neoplastic clone. With dual-color cytometric analysis, we showed that the large Sezary cells were near-tetraploid with a DNA index of 1.86, thereby demonstrating a direct relationship between cell size and ploidy. comparative genomic hybridization further showed chromosomal imbalances that were not revealed on conventional karyotyping. Our findings suggest that hyperdiploidy may be a marker of large cell transformation, so that when this karyotypic abnormality is found in mycosis fungoides-sezary syndrome, a search for such a complication is indicated.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/45. Need for an accurate molecular diagnosis to assess the donor origin of leukemia relapse after allogeneic stem cell transplantation.BACKGROUND AND OBJECTIVES: leukemia relapse occurring in donor cells after allogeneic hematopoietic stem cell transplantation has been reported in rare cases. cytogenetic analysis and molecular probing of variable number of tandem repeats (VNTRs) have been used to confirm this unusual event in the few cases so far reported in the literature. The aim of this study was to demonstrate that extensive molecular characterization of leukemic cells at diagnosis and relapse may be necessary to avoid many technical pitfalls possibly leading to an erroneous diagnosis of leukemia relapse in donor cells after allogeneic transplantation. DESIGN AND methods: We report the case of a 49- year old man who received an allogeneic transplantation from his HLA-identical sister because of BCR-ABL acute lymphoblastic leukemia (ALL). After having achieved complete hematologic and molecular remission, two years later an overt leukemia relapse occurred with cytogenetic findings suggesting a leukemia relapse in donor cells. The donor or patient origin of leukemic cells at relapse was further investigated by fluorescence in situ hybridization (FISH) karyotyping, reverse transcription (RT) polymerase chain reaction (PCR) analysis of BCR-ABL chimeric transcripts, PCR amplification of several VNTRs and the y chromosome-specific DYS14 sequence and finally by amplification, cloning and sequencing of the CDRIII region of the immunoglobulin heavy chain (IgH) gene. RESULTS: At the time of relapse, conventional and FISH karyotyping revealed the presence of a Phl chromosome and a female karyotype in all the 25 metaphases analyzed and PCR amplification of the y chromosome-specific DYS14 sequence was negative. Moreover, the molecular evaluation of hematopoietic chimerism performed by the NZ-22 VNTR allowed us to demonstrate that at the time of relapse, a consistent proportion of hematopoietic cells was of donor origin. However, the molecular cloning and sequencing of the CDRIII region of the immunoglobuin heavy chain (IgH) gene rearrangement in leukemic blasts at diagnosis and relapse demonstrated their identity thus formally proving the patient origin of both leukemic clones. INTERPRETATION AND CONCLUSIONS: While the simplest interpretation of the apparent female karyotype at relapse is the consequence of a loss of the y chromosome which in leukemic blasts took place along with duplication of an X-chromosome, this case strongly emphasizes the need for accurate and extensive molecular characterization to prove the donor origin of a leukemia relapse after allogeneic transplantation.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/45. Development of follicular dendritic cell sarcoma in hyaline-vascular Castleman's disease of the nasopharynx: tracing its evolution by sequential biopsies.AIMS: Hyaline-vascular Castleman's disease (HVCD) and follicular dendritic cell (FDC) sarcoma occurring in the nasopharynx are both extremely rare. We report the first case of transformation of the former into the latter as documented by sequential biopsies. The steps involved in the transformation were described in detail and the possible role of p53 studied. methods AND RESULTS: The patient presented at the age of 23 years with nasopharyngeal HVCD. Hyaline- vascular Castleman's disease with FDC overgrowth was diagnosed in a recurrence 8 years later, and a frank FDC sarcoma developed at the same site 11 years after initial presentation. The patient remained disease-free 3 years after excision and adjuvant chemotherapy. The FDC sarcoma comprised swirling fascicles of spindly cells with indistinct cell borders. The tumour cells expressed the FDC markers CD21, CD35 and CNA.42 and in-situ hybridization for Epstein-Barr virus-encoded RNAs was negative. Over-expression of p53 protein was observed in the FDC sarcoma and an increased number of weakly p53-positive spindly cells could also be demonstrated in the HVCD specimen. This finding suggested a possible role of p53 in the evolution from HVCD to FDC sarcoma. Critical analysis of the literature shows that, among the 13 reported cases of FDC sarcoma associated with Castleman's disease, possible progression from the latter to the former is documented in only two cases. CONCLUSIONS: The sequential changes observed in the current case provide further evidence to strengthen the role of HVCD as a possible precursor of FDC sarcoma. There is a possible role of p53 in the transformation process but confirmation by future studies is needed.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/45. Amplification of ERBB2, RARA, and TOP2A genes in a myelodysplastic syndrome transforming to acute myeloid leukemia.A patient is described with myelodysplastic syndrome (MDS) progressing to acute myeloid leukemia (AML) FAB M4. cytogenetic analysis revealed an unusual rearrangement between chromosomes 9 and 17, leading to a dicentric chromosome with an insertion of material of unknown origin between both chromosomes. By fluorescence in situ hybridization (FISH), the insertion was shown to be an amplification of part of 17q, involving ERBB2, RARA, and TOP2A genes. The median copy number of ERBB2, RARA, and TOP2A genes in the tumor cells was six (range: 4--10). Only one copy of the MPO gene at 17q21.3 was detected, suggesting a deletion of the telomeric part of 17q. To our knowledge, this is the first report of a 17q amplification in AML.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
6/45. The human formin-binding protein 17 (FBP17) interacts with sorting nexin, SNX2, and is an MLL-fusion partner in acute myelogeneous leukemia.We have cloned a fusion partner of the MLL gene at 11q23 and identified it as the gene encoding the human formin-binding protein 17, FBP17. It maps to chromosome 9q34 centromeric to ABL. The gene fusion results from a complex chromosome rearrangement that was resolved by fluorescence in situ hybridization with various probes on chromosomes 9 and 11 as an ins(11;9)(q23;q34)inv(11)(q13q23). The rearrangement resulted in a 5'-MLL/FBP17-3' fusion mRNA. We retrovirally transduced murine-myeloid progenitor cells with MLL/FBP17 to test its transforming ability. In contrast to MLL/ENL, MLL/ELL and other MLL-fusion genes, MLL/FBP17 did not give a positive readout in a serial replating assay. Therefore, we assume that additional cooperating genetic abnormalities might be needed to establish a full malignant phenotype. FBP17 consists of a C-terminal Src homology 3 domain and an N-terminal region that is homologous to the cell division cycle protein, cdc15, a regulator of the actin cytoskeleton in schizosaccharomyces pombe. Both domains are separated by a consensus Rho-binding motif that has been identified in different Rho-interaction partners such as Rhotekin and Rhophilin. We evaluated whether FBP17 and members of the Rho family interact in vivo with a yeast two-hybrid assay. None of the various Rho proteins tested, however, interacted with FBP17. We screened a human kidney library and identified a sorting nexin, SNX2, as a protein interaction partner of FBP17. These data provide a link between the epidermal growth factor receptor pathway and an MLL fusion protein.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
7/45. Small round cell tumor with biphenotypic differentiation and variant of t(21;22)(q22;q12).A 14-year-old boy presented with a soft tissue swelling on the outer aspect of his left upper arm. Examination of the tumor by light microscopy showed a small round cell tumor with a rare focus of myogenic differentiation. Myogenic differentiation was confirmed on ultrastructural examination by immunohistochemistry and reverse transcriptase polymerase chain reaction (RT-PCR). Conventional G-banding and fluorescent in situ hybridization (FISH) demonstrated a complex variant of t(21;22)(q22;q12). By RT-PCR, the EWS-ERG fusion transcript was defined as type 9e. This tumor was unusual in that it showed characteristics of myogenic and neural differentiation, and contained a rearrangement of the EWS gene consistent with a diagnosis of Ewing's sarcoma. This supports the hypothesis that a class of biphenotypic childhood sarcomas, with features of myogenic and neural differentiation, exists that may be related to the Ewing's sarcoma family of tumors.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
8/45. Barrett's adenocarcinoma of the esophagus with lymphoid stroma.We report a case of Barrett's adenocarcinoma of the esophagus with lymphoid stroma. We believe this is the first reported case of this entity, although six previous cases of esophageal lymphoepithelioma-like carcinoma have been reported. The esophageal tumor from a 58-year-old man was examined histologically. In situ hybridization to detect Epstein-Barr virus (EBV) was also performed. The tumor consisted of a poorly differentiated adenocarcinoma with dense lymphoid cell infiltration in the invasive portions and a well-differentiated adenocarcinoma without lymphoid stroma in the mucosa. Barrett's epithelium was observed adjacent to the carcinoma. No positive signals for EBV were detected in the tumor cells. Six previously reported patients with esophageal lymphoepithelioma-like carcinomas, and the current patient, all survived for longer than 24 months, a better outcome than that of patients with esophageal squamous cell carcinomas of usual type. The data suggest that this tumor arose as a mucosal, well-differentiated adenocarcinoma without lymphoid stroma and that EBV had no relation to either its pathogenesis or progression.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
9/45. New insights into the biology of multiple myeloma using a combination of May-Grunwald-Giemsa staining and fluorescence in situ hybridization techniques at the single cell level.Up to now only limited information is available about the significance of chromosomal aberrations in multiple myeloma (MM) and about the time point of the neoplastic transformation. fluorescence in situ hybridization (FISH) combined with standard May-Grunwald-Giemsa (MGG) staining or immunophenotyping on a single cell level were applied. Bone marrow (BM) samples were obtained from 11 patients with morphologically proven multiple myeloma. For detection of the chromosomal aberrations, we used FISH on interphase nuclei with commercially available centromere-specific probes for chromosomes 1, 7, 9, 11, 15, and 17 and further dna probes for 5p13, 5q31, Rb-gene (13q14), cyclin d1 gene (11q13), and p53 gene (17p13). The aberration rate differed between 14% and 71% on bone marrow smears. Using the combination of MGG and FISH we analyzed eight patients. A total of 2622 bone marrow cells were morphologically identified and investigated for their specific chromosomal aberrations. For all probes applied, 57 cells of the erythropoietic lineage, 698 cells of the granulopoietic lineage, and 168 lymphocytes showed two normal FISH signals. Of 1723 nuclei of plasma cells, 464 (26.9%) were also not aberrant, whereas all other nuclei of plasma cells (n=1259, 73%) showed a specific aberration. Combination of fluorescence immunophenotyping and in situ hybridization (FICTION) was applied in 10 of 11 patients. Seventy-eight investigated CD34-positive precursor cells did not show any specific aberration detected before in the plasma cell compartment. In conclusion, the combination of MGG and FISH on a single cell level demonstrated that only plasma cells bore the chromosomal aberration and MM did not evolve at an early cell level.- - - - - - - - - - ranking = 6keywords = hybridization (Clic here for more details about this article) |
10/45. Simultaneous occurrence of myelodysplastic syndrome and monoclonal B lymphocytes with a different clonal origin.Bone marrow and peripheral blood from a myelodysplastic syndrome patient with trisomy 13 and monoclonal B lymphocytes (without evidence of systemic lymphoma) were investigated for clonal lymphoid lineage involvement using interphase fluorescence in situ hybridization (FISH) and X-chromosome inactivation assay (HUMARA) on CD19 and CD34 sorted cells. trisomy 13 was detected in 55% of CD34 cells and in 5.5% of CD19 cells, the latter being comparable to the negative control specimen. X-chromosome inactivation showed both CD34 and CD19 cells to be monoclonal, though their inactivated X-chromosome was different. The results strongly suggested that both populations of CD34 and CD19 cells have originated from a different progenitor stem cell.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
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