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

To determine the usefulness of the H1 system, we applied it to 14 patients with acute leukemia and 19 patients with myelodysplastic syndrome (MDS). We revealed interesting cytogram patterns in several patients with acute leukemia, ALL (L2), ALL (L3), and AML (M7). In the basophil and lobularity cytogram, their blast cells were clustered mainly in the blast box. However, a small cluster appeared in the basophil area and was expressed as pseudo-basophilia of 4.4%, 9.6%, and 21%, respectively. We speculated that not only normal basophils but also some type of leukemic blasts could be resistant to rupture of the cell membrane induced by a surfuctant at a low pH. Characteristics of H1 cytogram and histogram pattern have hardly been reported in patients with MDS. From the analysis of H1 pattern of 19 cases, we found that the (1) the values of RDW and HDW were high in comparison to those for aplastic anemia and normal controls and (2) the MPXI (mean peroxidase activity index) was significantly low at the time of diagnosis. MPXI had declined at the terminal stage in cases of death with bone marrow failure. These characteristics were concluded to be useful in clinicopathological diagnosis using the H1 automatic hematological system.
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PMID:[The clinicopathological evaluation of automated cytochemical hematology system (Technicon H1) in patients with leukemia and myelodysplastic syndrome]. 151 30

The activation of protooncogenes (ras, fms and myc genes) by point mutations in hematological malignancies are described in this review. Ras mutations are found in a variety of human malignancies at codon 12, 13, and 61. Generally, N-ras mutations are frequent in hematological malignancies. Fms mutation at codon 301 and 969, which are seen in 10 to 20% cases of AML and MDS, increase tyrosine kinase activity of the fms products. Ras and fms mutations are postulated to influence leukemogenesis at rather early stages. Burkitt lymphomas are characterized by specific chromosomal translocations between c-myc gene and one of the immunoglobulin genes. Furthermore, mutations in the 3' border of the exon 1 of c-myc are frequent, and may play an additional role in pathogenesis of Burkitt lymphoma.
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PMID:[Activation of protooncogenes by point mutations in hematological malignancies]. 151 54

Aggressive chemotherapy of myelodysplastic syndromes is rarely feasible because these disorders predominantly occur in elderly patients who often have concurrent illnesses. Alternative treatment modalities must therefore be evaluated. This review summarizes the results that have been obtained with low-dose chemotherapy, especially with low-dose cytosine arabinoside (Ara-C). Overall response rates to treatment with low-dose Ara-C are about 40%, with some 20% of patients achieving a complete remission. Transition of MDS to AML does not reduce the probability of response. The therapeutic outcome cannot be reliably predicted by clinical or experimental parameters. Hematological toxicity is substantial, with approximately 10-25% treatment-related deaths. Duration of response is short and rarely exceeds one year. In terms of overall survival, low dose Ara-C does not appear to be superior to supportive care only. Other cytotoxic agents have not been studied in detail, but data available do not suggest an appreciable advantage over Ara-C. Before denying low-dose chemotherapy a helpful role in MDS, randomized studies should concentrate on those patients who can be expected to derive the greatest benefit. Because of their short survival, patients with RAEBt or those transformed to overt leukemia are such candidates.
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PMID:The role of low-dose chemotherapy in myelodysplastic syndromes. 156 Jun 70

Between 1978 and 1988 (median follow up 5 1/2 years), 396 newly diagnosed adults with AML (age range 14-59 years, median 44) received STT comprising daily Adriamycin: 25mg/m2 for 3 days, Cytosine arabinoside (ara-C): 100mg/m2 bd and 6-thioguanine: 100mg/m2 bd, each for 7 days. A maximum of 6 cycles was administered with as short an intercycle time as possible. No further treatment was given. Complete remission (CR) was achieved in 243/396 patients (62%), 71 patients (18%) having resistant leukaemia and 82 (21%) dying within 6 weeks. Antecedent myelodysplasia and advanced age correlated unfavourably with achievement of CR (p = less than 0.001 and 0.005 respectively). Sixty nine patients continue in first remission between 2 1/2 and 12 years; the median duration of remission was 1 year. M3 morphology (p = 0.005) and absence of hepatosplenomegaly (p = 0.001) correlated favourably with duration of remission. Ninety one patients remain alive with an actuarial survival of 22% at 5 years. More recently, additional consolidation comprising high-dose ara-C and total body irradiation (TBI) with autologous bone marrow transplantation (ABMT) has been evaluated in an open study. CR has been achieved in 41/66 patients under the age of 50 but only 19/41 have proceeded to ara-C + TBI + ABMT. Twenty two have not (early recurrence 10, allogeneic BMT 4, debility 6, refusal 2). 11/19 who proceeded to ablative therapy continue in remission (4 treatment related deaths, 4 recurrences) as compared to 9/22 who did not. Currently the overall median duration of remission for the 41 patients intended to proceed is identical to that of age-matched historical controls illustrating the difficulties inherent in demonstrating benefit for the use of myeloablative therapy and ABMT in patients with AML in first remission.
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PMID:Short term therapy (STT) for acute myelogenous leukaemia (AML). 157 52

Myelodysplastic syndromes originate from a pluripotent stem cell. This view, previously suggested by G-6-PD and cytogenetic investigations, has been established unequivocally by X-chromosome inactivation analysis based on DNA polymorphisms and by studies of mutated oncogenes. Two genomic alterations associated with MDS have been analyzed in more detail. Activation of the RAS oncogenes, preferentially N-RAS, is demonstrated in approximately 35% of MDS patients. Mutations in the FMS gene, encoding the CSF-1 receptor, are found in 16% of cases. Interestingly, RAS and FMS mutations are predominantly observed in disorders of myelomonoctic differentiation, i.e., the CMML subtype in MDS and the AML FAB type M4. Moreover, homozygous deletion of the FMS gene may be an important event in the genesis of the MDS variant 5q- syndrome. Preliminary data indicate that defects in tumor-suppressor genes, namely p53, may also contribute to the development of MDS. Different lines of evidence suggest that clinical preleukemia is preceded by a phase in which genetic alterations accumulate without any hematologic change. Cases in point are the detection of RAS and FMS mutations in healthy individuals who had been treated in the past with cytotoxic therapy for lymphoma, the frequent observation of clonal remission in AML patients, or the identification of oncogene mutations in healthy individuals without even a history of malignancy or chemotherapy. Possibly, either germline mutations of oncogenes or tumor-suppressor genes and the process of genomic imprinting may constitute additional factors that predispose hematopoietic stem cells to malignant transformation. Limited as they are, the currently available data suggest that accumulation of genomic lesions, rather than their precise order of development with respect to one another, characterize the multistep process of leukemogenesis in which MDS already represent more advanced stages. The prognostic significance of oncogene mutations in MDS patients is controversially discussed. This issue awaits prospective analyses taking into account the influence of treatment modalities. However, the clinical relevance of molecularly defined parameters has already been established for their use as clonal markers in determining the mode of action and efficiency of different therapeutic approaches.
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PMID:Molecular genetic aspects of myelodysplastic syndromes. 161 6

Thirty-four patients with MDS or AML following MDS were studied with regard to survival, peripheral blood values and bone marrow morphology. The effects of 1,25 dihydroxyvitamin D3 (D3) on differentiation (NBT positivity) and proliferation (3H-thymidine incorporation) were studied in suspension cultures of bone marrow cells. Twelve bone marrow donors served as controls. Normal cells showed spontaneous differentiation in vitro, but only 2/12 were induced to differentiation by D3. Myelodysplastic cells did not differentiate spontaneously, but cells from 18/34 patients differentiated after incubation with D3. Normal cells showed increased proliferation, myelodysplastic cells showed a heterogeneous response and leukemic cells reacted with decreased proliferation after D3 incubation. Poor survival was associated with low platelet counts, high percentage of bone marrow blasts (BM blast %), low spontaneous in vitro proliferation and absence of hypogranulation of myeloid cells. Platelet counts and hypogranulation retained their predictive value in a multi-variate analysis. Progression to AML was predicted by a high BM blast % and low scores for erythroid and total dysplasia. In conclusion, the pattern of in vitro proliferation showed prognostic value while the pattern of vitamin D3-induced differentiation failed to correlate to other parameters. An estimation of bone marrow dysplasia can be used to predict the development of AML. Our results add to the information about the biology of MDS and may be important for the evaluation of therapeutic trials.
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PMID:In vitro suspension culture reactions to 1,25 dihydroxyvitamin D3 in relation to bone marrow morphology and prognosis in patients with myelodysplastic syndromes. 162 79

Two different classes of therapy-related acute myeloid leukemia (t-AML) seem to emerge. One class follows therapy with alkylating agents, increases in frequency with age, often presents with myelodysplasia (MDS), responds poorly to chemotherapy, and shows monosomy 7(-7), monosomy 5(-5), or loss of various parts of the long arms of these chromosomes (5q- and 7q-). The other class is related to therapy with cytostatic drugs targeting at DNA-topoisomerase II, often presents with overt leukemia, responds more favorably to chemotherapy, and shows balanced chromosome aberrations, primarily translocations involving chromosome bands 11q23 and 21q22. These two classes of t-AML may have their counterparts in de-novo acute myeloid leukemia (de-novo AML).
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PMID:Two different classes of therapy-related and de-novo acute myeloid leukemia? 165 39

Blast-cells in Romanowsky-Giemsa stained bone marrow smears from 14 cases of primary myelodysplastic syndrome which consequently developed an acute myeloid leukemia and 28 cases of primary acute myeloid leukemia were analysed by a computer aided high resolution pattern recognition system. As control we used blast-cells from reactive affected bone marrow. Whereas blast-cell types in MDS and secondary AML showed overlapping features and a heterogenous distribution we could distinguish blasts in primary AML compared to "reactive" blasts. Opposite to this blasts in secondary AML showed no different pattern compared to "reactive" blast.
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PMID:[Pattern analytic investigations of blast cells in myelodysplastic syndrome and secondary acute myeloid leukemia]. 170 71

Most cases of acute myeloid leukaemia in the elderly and about 15% of the cases in younger patients follow a myelodysplastic disease. This disease may differ biologically from de novo AML making cure more difficult. Understanding post-MDS AML is difficult because of its preponderance in the elderly and the many complicating factors of treating old people. However, it is likely that post-MDS AML is more resistant to chemotherapy than de novo AML, that periods of pancytopenia last longer following chemotherapy and remissions are shorter. In younger patients high complete remission rates are achievable with aggressive chemotherapy and good supportive care. Such patients are best served by subsequent allogeneic bone marrow transplantation if possible, and if not then bone marrow autograft or a maintained remission should be considered. For older patients cure is unlikely and the choice between low-dose cytarabine and aggressive chemotherapy must be made if treatment is to be contemplated at all. The former leads to less hospitalisation and fewer side effects, but the latter gives a greater chance of a complete remission. This will not be long lasting.
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PMID:The treatment of acute myeloid leukaemia preceded by the myelodysplastic syndrome. 173 62

This is a review of preleukaemic states in children. In a prospective series of 109 children with AML the overt disease was preceded by MDS in 22 cases. Ten of these patients had Down's syndrome. Advanced FAB groups were represented in the series. An important subgroup is the bone marrow monosomy 7 syndrome. Cytogenetic anomalies are common in MDS, and multiple and complicated abnormalities develop in nearly all patients with progressing disease. Some children die before transformation to overt ANLL. Transformation usually occurs, few children survive. With cytostatic treatment the risk of irreversible aplasia is great. The choice of schedule should therefore be carefully considered. Bone marrow transplantation has proved beneficial in a number of cases, but these are still quite few. The dysfunction of the bone marrow preceding ALL is due to transient aplastic anaemia--spontaneous remission--overt ALL, often FAB type L1, immunophenotype CALLA. The ALL reacts to the same treatment as de novo ALL of the same type and the prognosis is the same.
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PMID:Bone marrow dysfunctions preceding acute leukemia in children: a clinical study. 173 77


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