1/748. MYC amplification in two further cases of acute myeloid leukemia with trisomy 4 and double minute chromosomes.We report two cases of trisomy 4 with double minute chromosomes (dmin): one in a woman with acute myeloid leukemia (AML), French-American-British subtype M2, the other in a man with chronic myelomonocytic leukemia. In the former case, many cells without trisomy 4 but with dmin were present, a finding not observed in previously reported cases. In both cases, fluorescence in situ hybridization studies demonstrated the double minutes to be MYC amplicons. Ten cases of AML with trisomy 4 and dmin have now been described; in the five cases investigated, the dmin have been shown to be amplified MYC gene sequences.- - - - - - - - - - ranking = 1keywords = leukemia (Clic here for more details about this article) |
2/748. Acute myelogenous leukemia with a t(2;17;4)(p13;q21;p16) aberration: effective treatment with all-trans retinoic acid and granulocyte colony-stimulating factor.The efficacy of all-trans retinoic acid (ATRA) in patients with acute promyelocytic leukemia (APL) has been well documented. However, ATRA is not as effective against other types of acute myelogenous leukemia (AML) or myelodysplastic syndromes. We present a patient with AML (FAB: M2) associated with a t(2;17;4)(p13;q21;p16) chromosomal defect in which the 17q21 breakpoint was not within the retinoic acid receptor alpha locus which is typically rearranged in APL. This patient was successfully treated with ATRA and granulocyte colony-stimulating factor and improvement of hematological parameters lasted for 19 months without the use of cytotoxic agents.- - - - - - - - - - ranking = 1keywords = leukemia (Clic here for more details about this article) |
3/748. A novel philadelphia chromosome-positive cell line with multipotential properties.A novel philadelphia chromosome-positive cell line was established from the peripheral blood of a patient with chronic myelogenous leukemia in megakaryoblastic crisis. This cell line, designated TN922 showed the positive phenotypes for myeloid, monocyte-macrophage, erythroid and megakaryocytic markers. The stimulation with phorbol 12-myristate 13-acetate (PMA) increased the expression of megakaryocytic markers including the platelet peroxidase activity, dimethylsulfoxide or transforming growth factor-beta promoted up-regulation of the erythroid markers. Stimulation with PMA, tumor necrosis factor-alpha or interleukin-6 also brought about the expression of monocytoid markers. These findings indicated that TN922 cell line has the property of acting as multipotential progenitor cells. TN922 cells showed gradual growth in the absence of growth factors but the addition of granulocyte/macrophage colony-stimulating factor (GM-CSF) promoted cell growth. The message of GM-CSF was detected in TN922 cells and the neutralizing antibody against GM-CSF receptor alpha-subunit suppressed cell growth. These results indicated that TN922 cell line proliferates in an autocrine secretion of GM-CSF.- - - - - - - - - - ranking = 0.16666666666667keywords = leukemia (Clic here for more details about this article) |
4/748. Identification of multiple copies of a 20q-chromosome in a case of myelodysplastic syndrome: a FISH study.In myelodysplastic syndromes (MDS) karyotypic aberrations identify subgroups of patients with distinct clinical-morphological features and can be relevant in risk assessment of developing leukemia. Often conventional cytogenetic analysis is not sufficiently informative due to the presence of partially or completely unrecognizable chromosome markers. By chromosome microdissection (MD) and fluorescence in situ hybridization (FISH) we investigated the nature of a karyotypic marker occurring in multiple copies in one case of MDS arisen in a patient previously treated for breast cancer. Results showed dicentrics derived from telomeric fusion between interstitially deleted 20q-chromosomes. The abnormal karyotype resulted into polysomy for a deleted chromosome 20q.- - - - - - - - - - ranking = 0.16666666666667keywords = leukemia (Clic here for more details about this article) |
5/748. Acute promyelocytic leukemia with additional chromosomal abnormalities and absence of Auer rods.We report 4 acute promyelocytic leukemia cases that demonstrated karyotypic abnormalities in addition to the classic t(15;17) translocation and did not contain any Auer rods in leukemic blasts and dysplastic promyelocytes, either in the peripheral blood or in the bone marrow. Morphologically, 2 cases were characterized as the common or hypergranular type, and 2 were otherwise typical of the microgranular variant. Three patients had typical clinical and laboratory signs of disseminated intravascular coagulation. Immunophenotypic analysis of the blasts and dysplastic promyelocytes by dual-color flow cytometry revealed an immunoprofile consistent with acute promyelocytic leukemia. cytogenetic analysis of the bone marrow revealed the following karyotypes: case 1, [47,XY,t(15;17)(q22;q12), 21]; case 2, [47,XY,t(15;17)(q22;q12),-16, 2 mar]; case 3, [47,XX,t(15;17)(q22;q12)ider(17)(q10), 8]; and case 4, [47,XY,der(5)t(5;?9)(p15;q12).t(15;17)(q22;q12]. review of an additional 7 cases with t(15;17) as the sole cytogenetic abnormality revealed Auer rods in all cases. Our findings emphasize the importance of cytogenetics in evaluating acute myeloid leukemias. Acute promyelocytic leukemia without Auer rods, which may be morphologically confused with other types of leukemia (in particular, acute myeloblastic leukemia, type M2 or M5) or agranulocytosis with maturation arrest, appears to be associated with additional chromosomal abnormalities and possibly a poorer prognosis.- - - - - - - - - - ranking = 1.6666666666667keywords = leukemia (Clic here for more details about this article) |
6/748. Clonal analysis of a case of multifocal oesophageal (Barrett's) adenocarcinoma by comparative genomic hybridization.Oesophageal adenocarcinomas arising in Barrett's epithelium occasionally present as multiple lesions. This could be due to either a multifocal presentation of the same tumour, or different neoplasms arising simultaneously in a dysplastic Barrett's oesophagus ('field cancerization'). This is a report of the genetic analysis of multiple neoplastic sites in a Barrett's oesophagus with an extensive area of dysplasia. In addition, the dysplastic Barrett's epithelium was evaluated. For the genetic screening, comparative genomic hybridization (CGH) allowed evaluation of the whole genome of each specimen. Five cancerous regions were selected and subsequently dissected from paraffin-embedded tissue blocks. The use of archival materials enabled a targeted collection of representative tumour locations. Multiple genetic aberrations were detected by CGH in all cancer sites. Losses on 3p, 4, 7q, 18q, and Y, as well as gains on 8q, 9q, 12p, 13q, 17q, 20p and X, were found in each specimen. In four out of the five lesions, simultaneous losses on 9p, 15q, and 16q, with concomitant gains on 5p, 7q, and 10p, were disclosed by CGH. Adjacent high-grade dysplastic Barrett's mucosa shared the losses on 3p, 4, 7q, 9p, 18, and Y, as well as the gains on 5p, 7q, 13q, 17q, and X, thereby confirming its precursor status. Within this single and rare case of multifocal Barrett's adenocarcinoma, a monoclonal genotype was present. This must have been caused by an extensive outgrowth of a single tumour.- - - - - - - - - - ranking = 0.0010166675640598keywords = precursor (Clic here for more details about this article) |
7/748. Discordant expression of myeloid antigens and myeloperoxidase in a case of t(8;21) positive AML expressing CD7.We describe a case of acute myeloid leukemia (AML) showing myeloperoxidase (MPO)-positive and myeloid antigens negative. Although the leukemic cells showed few granules in May-Grunwald Giemsa staining, cytochemical MPO staining revealed that most of the blast cells strongly reacted with MPO. The leukemic cells did not express myeloid antigens (CD13, CD33), nor B-lymphoid or T-lymphoid antigens on the cell surface using flow cytometry, however. The cells did express CD34 and CD7. Discordant expression of MPO and myeloid antigens was also confirmed by electron microscopic MPO staining and by immunocytochemistry using a streptoavidin-biotin alkaline phosphatase labeling technique. Cytogenetic studies showed 46, XX, t(8;21) (q22;q22), del (9) (q22) in the bone marrow cells. In addition, AML1/ETO chimeric mRNA was detected from these cells. We summarize eight reported cases of MPO positive and myeloid antigens negative AML. Five of nine cases including our case had the same chromosomal abnormality of t(8;21) (q22;q22) and showed better prognosis than the other cases.- - - - - - - - - - ranking = 0.16666666666667keywords = leukemia (Clic here for more details about this article) |
8/748. Identification of amplified genes in a patient with acute myeloid leukemia and double minute chromosomes.A case of acute myeloid leukemia (M2) with double minute chromosomes and complex karyotypic abnormalities was analyzed cytogenetically and molecularly. comparative genomic hybridization (CGH) showed that the 8q24 region that contains the MYC oncogene was not amplified. Instead, amplification of chromosomal regions 11q23-->qter and 9p11-->pter was identified. Southern blot analysis confirmed the CGH findings and showed that the ETS1, FLI1, SRPR, NFRKB, and KCNJ5 genes located at 11q23-->24 were amplified, whereas the MLL at 11q23 was not amplified. Additionally, the IFN beta 1 and CDKN2A genes at 9p were amplified, but to a lesser degree. This is the first example of a case of acute myeloid leukemia with double minute chromosomes that has not involved amplification of either the MYC or the MLL genes.- - - - - - - - - - ranking = 1keywords = leukemia (Clic here for more details about this article) |
9/748. A group of previously not recognized cytogenetic abnormalities in myeloid hematological malignancies.We have identified a group of previously not reported chromosome abnormalities related to myeloid hematological malignancies. Cases 1 and 2 were observed to have an additional i(4)(p10) as the sole anomaly with similar clinical features of myeloid disorders; that is, acute nonlymphocytic leukemia (ANLL-M2) and myelodysplastic syndrome (MDS)-refractory anemia with an excess of blasts in transformation, respectively. fluorescence in situ hybridization studies with the use of a 4p-specific microdissection probe further confirmed the presence of an i(4)(p10) in these patients. Case 3 was diagnosed with ANLL-M1 and had an additional i(8)(p10) as the only change, also confirmed by a whole-chromosome painting procedure. In cases 4-6, deletions of 18q at breakpoints q12, q23, and q21 were identified as the sole anomaly in a myeloproliferative disorder (MPD), MPD, and MDS, respectively. X-autosome translocations other than t(X;10)(p11;p11) and t(X;11)(q13;q23) have not been reported as recurrent or primary changes in hematological disorders. In the present study, a t(X;9)(q26;q22) and t(X;5)(q13;q33) as the sole anomaly were found in cases 7 and 8, respectively. Both cases had the same diagnosis of MDS. Considering that trisomies 4 ( 4) and 8 ( 8) are common anomalies in MDS and ANLL, our findings strongly indicate that amplification of genes on 4p and 8p, but not on 4q and 8q, may play a crucial role in the pathogenesis of MDS and ANLL. In addition, genes on 18q12-23 and on Xq13-26 may be involved in the pathogenesis of myeloid disorders.- - - - - - - - - - ranking = 0.16666666666667keywords = leukemia (Clic here for more details about this article) |
10/748. Transient leukemoid disorder in a newborn with down syndrome followed 19 months later by an acute myeloid leukemia: demonstration of the same structural change in both instances with clonal evolution.A transient leukemoid disorder (TLD) was observed in a newborn with down syndrome (DS), demonstrating a clonal abnormality: 47,XX,der(X;15)(p10;q10), 21(c). Spontaneous remission was observed, but 19 months later an acute leukemia from the myeloid series was discovered. Cytogenetic study revealed the same structural change as at birth, with karyotypic evolution corresponding to addition of one chromosome 8 and a fourth chromosome 21. These findings demonstrate, at least in our patient, that TLD and the subsequent acute leukemia are closely related and that TLD, closely related to DS, must be viewed as a preleukemic disorder undergoing spontaneous remission. A review of literature data shows that most cytogenetic studies reported so far are related to either TLD or acute leukemia in DS. Serial studies performed in the same patient are quite infrequent and, to the best of our knowledge, there is only one other report demonstrating a cytogenetic relation between TLD and the subsequent acute leukemia.- - - - - - - - - - ranking = 1.3333333333333keywords = leukemia (Clic here for more details about this article) |
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