UMLS:C0026986 - FACTA Search

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Query: UMLS:C0026986 (myelodysplastic syndrome)
14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The classification of acute leukemia has almost invariably been based on the morphologic diagnosis into two broad categories: acute lymphocytic and acute myeloid leukemia. Despite the wide range of morphologic variation in both groups, strict criteria to define the subgroups have only recently been proposed. The conventional markers for B and T cells are now being applied to leukemic cells as are cytochemistry and electron microscopy, terminal deoxynucleotidyl transferase, serum lysozyme, and surface markers, E-rosettes, membrane immunoglobulin, antinull acute lymphocytic leukemia antiserum, and Fc and C3 receptors. The myelodysplastic syndromes may mimic acute leukemia and it is important that they be identified and treated appropriately. The high incidence with which chronic myelomonocytic leukemia terminates in acute leukemia suggests that it is a preleukemic condition, whereas refractory anemia with excess blasts and acquired idiopathic sideroblastic anemia may have long, drawn-out courses. Only a small population of patients with the latter conditions develop acute leukemia.
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PMID:Classification of acute leukemia. 33 70

Sera of 25 healthy controls and 75 patients suffering from myelodysplastic syndromes (MDS) were investigated for serum concentration of interleukin-1 alpha (IL-1 alpha), IL-3, IL-6, granulocyte-colony-stimulating factor (G-CSF), granulocyte-macrophage-CSF (GM-CSF), erythropoietin (Epo), and tumor necrosis factor-alpha (TNF-alpha). According to French-American-British (FAB) classification, 21 refractory anemia (RA), seven refractory anemia with ring sideroblasts (RARS), 15 chronic myelomonocytic leukemia (CMML), 12 refractory anemia with excess of blasts (RAEB), and 20 RAEB in transformation (RAEBt) were examined. TNF-alpha levels were inversely correlated with lower levels of hemoglobin concentration (r = -0.31, p = 0.005), irrespective of the requirements for transfusion in anemic MDS patients. Significant differences in TNF-alpha levels between CMML (26.2 +/- 5.9 pg/ml) and the FAB subgroups (16.1 +/- 1.6 pg/ml) were detected. There was an overall inverse relationship between the level of erythropoietin and the degree of anemia, but a wide range of Epo response between patients with similar hemoglobin concentrations. Serum levels of IL-1 alpha and GM-CSF were undetected in most of the patients. In 57% of the samples there were detectable levels of G-CSF, without a correlation of the serum levels with blood cell counts, nor with any of the FAB subcategories. Overall, 29% and 25% of the patient sera exhibited elevated IL-3 and IL-6 levels, respectively. There was no correlation of the serum levels with any of the blood counts, other cytokines, nor FAB subcategories. In conclusion, simple negative feedback mechanism between a specific cytokine and the production of blood cells seems not to be the case in MDS, except for red cell production and erythropoietin concentration. Our data may suggest the involvement of TNF-alpha in the pathogenesis of anemia in MDS.
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PMID:Measurement of serum cytokine levels in patients with myelodysplastic syndromes. 128 Jul 51

In a retrospective analysis we assessed the data of 46 patients with myelodysplastic syndromes (MDS), who had received more than 50 blood transfusions during the course of disease. The number of units given ranged from 50 to 155 (mean 79). 20 patients (RA n = 4, RARS n = 12, RAEB n = 1, RAEB/T n = 2, CMML n = 1), followed up between 8 and 108 months (mean survival time 39.4 months), developed a secondary hemochromatosis. More than 40% of the patients showed signs of heart failure, in some cases accompanied by cardiac arrhythmias. 11 patients also suffered from hepatopathy and 5 developed diabetes mellitus. Secondary hemochromatosis was particularly common in patients with RARS. Refractory congestive heart failure secondary to hemochromatosis was the cause of death in 14 patients, whereas none died from hepatic insufficiency. We conclude that the risk of secondary hemochromatosis should not be neglected in polytransfused patients with MDS. In some cases, particularly those with favorable prognostic features of MDS, it may shorten life expectancy. The availability of a new oral iron chelator (1,2-dimethyl-3-hydroxypyrid-4-one or L1) offers a promising and practicable approach to prevent this complication.
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PMID:[Secondary hemochromatosis in polytransfused patients with myelodysplastic syndromes]. 128 62

Myelodysplastic syndromes (MDS) include hemopoietic cytopenias of different origin, which are usually refractory to treatment. Therefore MDS patients should generally be treated conservatively. Transfusions of packed red cells (given in a strict regimen to minimize the risk for secondary hemochromatosis) may be sufficient to maintain a good quality of life. Indications for cytotoxic treatment include signs of progression of the disease. In patients with symptomatic cytopenias low-dose cytarabine (ara-C) should be tried. It is essential then to monitor each patient individually and to avoid fixed treatment schedules. Standard (high-dose) chemotherapy in MDS, is associated with a high mortality and a low response rate, and should be considered only in younger patients with advanced MDS. Allogeneic bone marrow transplantation (BMT) may be offered to younger MDS patients, when a suitable donor is available. Treatment with differentiation inducers has not met with expectations and should not be used outside clinical trials at the present. The use of recombinant hemopoietic growth factors (GF) seems promising. GF, like GM-CSF, G-CSF, IL-3, and erythropoietin, can be used either alone or in combinations, to support failing peripheral blood values, and decrease the risk for lethal complications. GF can also be given together with chemotherapy, in an effort to make the leukemic clonogenic cells more susceptible to cytotoxic drugs. Other treatments for MDS include: IFN-alpha and etoposide, with responses primarily in chronic myelomonocytic leukemia; hem arginate, whose role is still not clear; and corticosteroids, but only in carefully selected cases.
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PMID:Therapeutic aspects of myelodysplastic syndromes in chronic phase. 131 Jan 27

To determine the clonal nature of hematopoiesis and to assess lineage involvement in patients with myelodysplastic syndromes (MDS), we used restriction fragment length polymorphisms of the X-linked genes phosphoglycerate kinase (PGK1) and hypoxanthine phosphoribosyltransferase (HPRT) and the X-linked probe M27 beta. Eleven female MDS patients heterozygous for at least one of these probes were studied: 3 with refractory anemia (RA), 2 with RA with ringed sideroblasts (RARS), 2 with chronic myelomonocytic leukemia (CMML), and 4 with RA with excess of blasts in transformation (RAEB-t). All exhibited clonal hematopoiesis as determined by Southern analysis of DNA prepared from peripheral blood (PB) and/or bone marrow (BM) cells. In three of the six patients heterozygous for the PGK1 gene, purified cell suspensions of polymorphonuclear cells (PMN), monocytes, lymphocytes, and/or T cells prepared from PB were tested. In addition, five of these patients were analyzed by a polymerase chain reaction (PCR)-based procedure as described recently. This method was slightly adapted to facilitate the analysis of cell lysates of fluorescence-activated cell sorted (FACS) monocytes, T and B lymphocytes, and natural killer (NK) cells. The outcome of Southern and PCR analysis was concordant, showing that PMN and monocytes were clonally derived, whereas circulating T and B lymphocytes and NK cells exhibited random X-chromosome inactivation compatible with a polyclonal pattern. To address the question of whether T cells are derived from unaffected progenitor cells or that their origin had antedated the onset of MDS, naive and memory T cells were analyzed separately. Both subsets showed a polyclonal pattern. However, in one patient analysis of constitutive DNA suggested a skewed methylation, and the presence of clonal lymphocytes against a background of polyclonal lymphoid cells cannot be ruled out in this patient. PCR analysis of PB and BM cells showed a nonrandom, unilateral pattern of X-inactivation, compatible with a mixture of clonally (myeloid) and polyclonally (lymphoid) derived cells. In conclusion, in some patients, MDS represents a disorder with clonal hematopoiesis restricted to cells of myeloid origin, whereas a random X-inactivation pattern is found in lymphoid cells.
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PMID:Clonal involvement of granulocytes and monocytes, but not of T and B lymphocytes and natural killer cells in patients with myelodysplasia: analysis by X-linked restriction fragment length polymorphisms and polymerase chain reaction of the phosphoglycerate kinase gene. 135 10

Material from 63 cases with primary myelodysplastic syndromes (P-MDS) (French-American-British [FAB] types: refractory anemia [RA] = 21; RA with ring sideroblasts [RARS] = 8; RA with excess of blasts (RAEB) = 10; RAEB in transformation (RAEBt) = 6; chronic myelomonocytic leukemia [CMML] = 10 and unclassifiable = 8, ie, bone marrow aspiration was inadequate and stringent FAB criteria were not applicable) was analyzed for bone marrow histologic and immunohistochemical patterns. Standard Giemsa, hematoxylin and eosin (H&E) and reticulin stains were used for morphologic assessment. To identify the cell lineage precisely, chloroacetate esterase staining and an indirect immunoperoxidase technique using mouse monoclonal antibodies CD15, CD68, HLA-DR, and rabbit polyclonal CD3 and UEA-1 (lectin) was developed on formalin-fixed paraffin embedded bone marrow biopsies (BMB). The immunohistochemical assessment permitted accurate identification of dysplastic features such as mononuclear and binuclear megakaryocytes, Pelger-Huet neutrophils, and binuclear erythroblasts. Additional bone marrow histologic and immunohistochemical features observed were heterogeneity of immunohistochemical staining in various cell lineages, megakaryocytic emperipolesis, alteration of bone marrow microarchitecture, intravascular clusters of hematopoietic cells, and the types of benign lymphoid aggregates. The nature of abnormally localized immature precursors (ALIP) was discerned. Three types of clusters of immature cells were found that were difficult to distinguish on Giemsa and H&E morphology, these were erythroid aggregates (n = 18); megakaryocytic aggregates (n = 4), and immature granulocytic and monocytic aggregates (n = 32). The bone marrow histologic and immunohistologic patterns permitted the identification of four groups of clinical relevance: Group 1, cases with predominant erythroid hyperplasia and without ALIP (n = 15); group 2, cases with prominent myeloid hyperplasia and presence of ALIP (n = 32); group 3, cases with hypoplastic MDS (n = 10); and group 4, cases with hyperfibrotic MDS (n = 6). Statistical analysis showed a significant difference in survival and leukemic transformation between groups 1, 2, 3, and 4, with cases in group 2 showing the worst prognosis with early death due to increased propensity to leukemic transformation and cytopenia-related complications (P less than .0001). We conclude that immunohistochemistry is feasible on routinely processed BMB and the information obtained is of diagnostic and prognostic importance in P-MDS. The phenotype of ALIP varies with the morphologic and histologic subtypes of MDS and the term should be reserved for cases in whom the clusters in the intertrabecular region are of myeloid (granulocytic and monocytic) lineage on immunohistochemistry.
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PMID:Primary myelodysplastic syndromes: diagnostic and prognostic significance of immunohistochemical assessment of bone marrow biopsies. 137 Feb 3

Erythropoiesis in response to erythropoietin (Epo) in myelodysplastic syndrome (MDS) in vitro and in vivo is severely impaired. We investigated the stimulative effect of c-kit ligand (KL) on the erythroid colony-forming abilities of bone marrow cells from 17 patients with MDS. The effects of normal donor-derived marrow were examined in comparison. Suppression of erythroid colony formation in MDS in response to Epo could not be restored by the addition of interleukin-3 (IL-3) to culture. In cultures dishes supplemented with KL, erythroid colony formation was dramatically enhanced, regarding both colony number and size. Colony-forming abilities by MDS progenitors were improved following costimulation with KL, particularly in refractory anemia (RA) and refractory anemia with ring sideroblasts (RARS); however, little enhancement was apparent following KL stimulation of marrow from patients with refractory anemia with excess of blasts (RAEB), refractory anemia with excess of blasts in transformation (RAEB-t), and chronic myelomonocytic leukemia (CMML). These results suggest that KL responsiveness of patients with low-risk MDS may still be intact, and that with progression to high-risk MDS, erythroid progenitors lose proliferative reactivity to both KL and Epo stimulation. KL may have a therapeutic role in restoring erythropoiesis in a subset of patients with MDS.
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PMID:Kit ligand improves in vitro erythropoiesis in myelodysplastic syndrome. 138 Dec 39

We have isolated a lymphoid cell line, MDS, from the pleural exudate of a patient with chronic myelomonocytic leukemia. The cells are biphenotypic, containing various T-cell and myeloid markers, and are surface negative for CD4 and CD8 but have low CD4 mRNA. The cells grow in suspension with a doubling time of 15 hr, have been karyotyped as trisomy 21, are negative for human immunodeficiency virus type 1 (HIV-1), and are tumorigenic in the nude mouse. We have isolated two stable HIV-1-producing cell lines, MDS-T, by transfecting MDS cells with pHXBc2, and MDS-I, by infecting MDS cells with HIV-1IIIB. In 24 hr, 1 x 10(5) MDS-T or MDS-I cells produce 46 ng of p24 per ml and reverse transcriptase that is capable of incorporating 0.2 pmol of [32P]TTP into oligo(dT).poly(A). Ultrastructural studies showed numerous mature viral particles in MDS-T and MDS-I cells that are capable of infecting T cells. HIV-1 infection could be inhibited by 25% in the MDS cells with the anti-CD4 antibody Leu 3a. For over a year MDS-T and MDS-I cells have been producing high concentrations of HIV-1 in culture. A subclone derived from the MDS cells behaves like the parent cells when transfected or infected with HIV-1. In contrast to other T-cell lines, neither phorbol 12-myristate 13-acetate nor tumor necrosis factor alpha stimulated the replication of HIV-1, whereas bromoadenosine 3',5'-cyclic monophosphate or interferon alpha caused 50% and 80% inhibition of reverse transcriptase production, respectively. These chronically infected T-cell lines are a useful model system to study the effect of anti-HIV agents and cellular factors required for HIV-1 replication.
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PMID:Productive nonlytic human immunodeficiency virus type 1 replication in a newly established human leukemia cell line. 143 50

In a phase II study, 21 patients with MDS (RAEB, RAEBt, CMML and RA and RAS with severe cytopenia) were randomized to be treated with 3 courses of GM-CSF (3 micrograms/kg/day s.c.) alone (11 patients) or in combination with AraC (20 mg/m2/d s.c.) (10 patients) for 14-d periods, interrupted by 14-d rest periods. Eight patients discontinued the treatment. In the GM-CSF group a marked increase in WBC and neutrophil counts during each course of treatment administration were seen in most patients. Platelet counts decreased in 14 of 24 courses of treatment in the GM-CSF plus AraC group but in none of the GM-CSF group. Although the changes in the circulating blood cells were transient and the counts tended to return to the pretreatment levels during the rest periods, some more durable effects were seen. In 3/6 patients of the GM-CSF group who completed the designed treatment, both WBC and neutrophils remained elevated above the pretreatment levels throughout the 3-month period of treatment, while in one of them thrombocytopenia improved considerably. In the GM-CSF plus AraC group, 4 out of the 7 patients who completed the treatment showed an improvement of neutropenia as well as anaemia. In these 4 patients the BM percentage of blasts was also decreased. In conclusion, the results of this study indicate that GM-CSF given intermittently improves leukopenia in some patients with MDS. In addition, the administration of GM-CSF seems to prevent granulocytopenia of concurrent AraC treatment and may be of benefit in the treatment of these diseases.
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PMID:Treatment of myelodysplastic syndromes with human granulocytic-macrophage colony stimulating factor (GM-CSF) or GM-CSF combined with low-dose cytosine arabinoside. 144 28

Sixteen children with myelodysplastic syndrome as defined by the French-American-British co-operative group are presented. The mean age was 10.5 (2.5 to 16) years, with a male predominance. All patients belonged to the more aggressive subtypes of myelodysplastic syndromes. Seven patients presented with refractory anaemia with excess blasts, six had refractory anemia with excess blasts in transformation, and three had chronic myelomonocytic leukemia. Cytogenetic analysis done in 7 of the 16 patients, revealed karyotype abnormalities involving chromosomes 7, 8 and 17. One patient with Down's syndrome had karyotype of 47, XY, +21 (major clone) and 46, XY (minor clone). Five of these patients evolved to acute leukemia. The mean duration of survival was 5.5 months. Aggressive chemotherapy as a primary line of treatment induced remission in five out of six patients. Predominance of aggressive types of myelodysplastic syndromes in children and their good but short-lived response to aggressive chemotherapy suggests the need for early bone marrow transplantation following chemotherapy.
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PMID:Childhood myelodysplastic syndromes: clinical features, cytogenetics and prognosis. 145 62

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