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

The proliferation characteristics of leukemic cells may be a determining factor in disease course and response to therapy. The present study compares the rate of cell-cycle progression in the bone marrow of 16 hematologically normal subjects, 19 patients with acute myeloid leukemia (AML), and 23 patients with myelodysplastic syndrome (MDS). The frequency of sister chromatid exchanges (SCE) in bone marrow cells is also compared. MDS and AML patients showed a reduction in the rate of cell-cycle progression compared with normal subjects. Patients with 'high risk' MDS (RAEB/RAEB-t) did not differ significantly from patients with AML but had a significantly slower rate of cell-cycle progression than patients with 'low-risk' MDS (PASA/RA). There was no correlation between the rate of cell-cycle progression and clonal karyotype status or the percentage of blast cells in either MDS or AML. There were no significant differences in SCE frequency between normal subjects and MDS or AML patients.
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PMID:Cell-cycle progression rates and sister chromatid exchange frequencies in the bone marrow of patients with myelodysplastic syndrome and acute myeloid leukemia. 152 Dec 37

Trisomy 4 has been identified previously as a chromosome abnormality associated with acute nonlymphocytic leukemia (ANLL) with myelomonocytic lineage and in myelodysplastic syndromes (MDS). We report a case of acute lymphocytic leukemia (ALL) (French-American-British, FAB L1) in a 42-year-old Japanese man, with trisomy 4 as the sole chromosomal anomaly. Immunophenotypically, the leukemic blasts demonstrated reactivity with CD2, CD5, and CD7 and indicated on early stage of T cell.
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PMID:Trisomy 4 in a case of acute lymphocytic leukemia (L1). 152 Dec 41

A 41-year-old woman with a myelodysplastic syndrome complained of diarrhea with malabsorption and protein-losing enteropathy after splenectomy. No cause was found and various therapeutic regimens were not effective. Pathological examination of biopsies from stomach, small intestine, and large bowel showed infiltrations interpreted as inflammatory on routine technics. Blast cell infiltration was found on electron microscopy. Treatment by citarabine induced normalization of leukocytosis, and diarrhea disappeared. Six months after the onset of illness, she developed acute myeloblastic leukemia and died of infectious pneumonia. Blastic infiltration of the lamina propria could be responsible for the determinism of symptoms, because of the lack of another etiology, the intensity of the blastic infiltration and the effect of cytotoxic therapy, even in the absence of new biopsies.
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PMID:[Diarrhea with malabsorption and exudative enteropathy caused by intestinal myeloid involvement in a patient with myeloproliferative syndrome]. 152

In order to analyze the correlation between environmental exposure and the clinicopathological picture in acute myeloid leukemia (AML), cytogenetic, cyto-immunologic and clinical studies were performed in 70 newly diagnosed AML patients, 30 of which were anamnestically exposed to pesticides (21 cases) or to organic solvents (9 cases). Clonal chromosome aberrations, with involvement of chromosome 5 and/or 7 were more frequently encountered among exposed patients. While the classical t(15;17), t(8;21) and t(9;11) were detected more frequently among non-exposed patients, other recurring chromosome changes in the exposed group were: rearrangements leading to total or partial monosomy 17p (5 cases), structural aberrations involving the band 16q22 (4 cases), trisomy 11q (2 cases), breaks involving bands 6p23, 7p14, 11q13 (2 cases each). Cytologically, trilineage myelodysplasia was observed in 21 exposed patients, whereas morphologic aberrations of the non-blast cell population were confined to a minority of cells in most patients non-exposed. Immunologic studies revealed positivity for the CD34 stem cell marker in 80% exposed patients vs 22% in the non-exposed group. Conventional chemotherapy achieved complete remission in 3/21 patients exposed and in 16/32 patients non-exposed. Median survival was 2 months in the former group and 9 months in the latter group. These findings show that AML following occupational exposure to pesticides and organic solvents may represent a distinct cytogenetic and clinicopathological entity.
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PMID:Morphologic, immunologic and cytogenetic studies in acute myeloid leukemia following occupational exposure to pesticides and organic solvents. 152 67

Twenty-one patients (median age = 34, range = 10-49; F:M = 7:14) received a preparative regimen consisting of busulfan 4 mg/kg/day x 4, cytosine arabinoside 2 g/m2/12 h x 4 and cyclophosphamide 60 mg/kg/day x 2 ('BAC' regimen) for allogeneic bone marrow transplantation. Out of 12 patients with acute myeloid leukemia (AML), two were in first remission, six were in second remission and four had resistant, relapsed disease or prolonged marrow aplasia after induction chemotherapy. Five of the 12 patients with AML had secondary AML. Four patients had transfusion-dependent myelodysplastic syndrome. Three patients with chronic myeloid leukemia were in the accelerated phase and two were in the blastic phase. Organ toxicities related to the preparative regimen were graded. Liver toxicity occurred in 11 patients, two of these were fatal veno-occlusive disease (VOD) (10%). Nineteen of the 21 patients had grade 2 or less diarrhea, and 13 also had mucositis. One patient developed grade 3 cardiac toxicity, and one other patient had grade 1 skin toxicity. Four patients had gross hematuria related to treatment (19%). No renal, pulmonary or CNS toxicities were encountered. Ten patients have died, two from regimen-related hepatic VOD. Of the remaining eight deaths, four were from respiratory failure in four patients (one case each of Pneumocystis pneumonia, CMV pneumonia, bronchiolitis obliterans associated with chronic graft-versus-host disease, and interstitial pneumonitis complicated pulmonary emboli), and one patient each from GI bleeding, cardiac arrhythmia, sepsis and CNS bleeding. Thus far, only one patient transplanted for secondary AML in second remission relapsed at day 230.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Allogeneic bone marrow transplantation in high-risk myeloid disorders using busulfan, cytosine arabinoside and cyclophosphamide (BAC). 154 49

A review of all of the cases of Fanconi anemia (FA) reported to the International Fanconi Anemia Registry (IFAR) indicates that at least 15% manifest acute myelogenous leukemia (AML) or preleukemia. These patients usually have karyotypically abnormal bone marrow clones, but do not exhibit chromosomal translocations involving breakpoints associated with specific oncogenes; leukemia in FA is more likely to be a multi-step process than a single step transformation. The cellular defect in FA results in chromosomal instability, hypersensitivity to DNA damage, and hypermutability for allele-loss mutations. An update of current research to identify the molecular defect in FA is presented. Characterization of the FA genes should further our understanding of the etiology of leukemia.
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PMID:Fanconi anemia and leukemia: tracking the genes. 154 31

The ras proto-oncogene family encodes a group of 21 kDa nucleotide-binding proteins. Activating mutations of ras genes are associated with certain types of malignancies, indicating that they are related in some way to the malignant process. We have examined bone marrow cells from nine children with myelodysplastic syndromes (MDS) and 35 with acute myeloid leukemia (AML) for activating point mutations of ras genes by in vitro amplification using polymerase chain reaction (PCR), oligonucleotide hybridization and sequencing of PCR products. We found N-ras mutations in cells from 3 of 9 children (33%) with MDS and only 2 of 35 children with AML (6%; 95% confidence interval is 0.7-19%). All mutations the second nucleotide of codon 12 or the first nucleotide of codon 61 of N-ras. There was no apparent correlation with clinical or laboratory characteristics, including karyotype; however, an association of N-ras activation with the most aggressive type of MDS was noted. Among the patients with MDS, 2 of 6 with monosomy 7 had N-ras mutations; however, three children with monosomy 7 which presented with AML lacked ras mutations. One patient was studied at time of diagnosis of MDS and again after progression to AML. At the preleukemic stage of disease, an N-ras mutation was identified; however, after development of AML this mutation was not present in the leukemic clone. In conclusion, these data show that ras mutations, while not necessary for leukemic transformation, may be important for the initiation of preleukemias evolving into overt AML.
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PMID:Prevalence of N-ras mutations in children with myelodysplastic syndromes and acute myeloid leukemia. 154 47

To assess potential differences in genetic predisposition to myeloid neoplasia, we evaluated the karyotypes and reviewed results of cytogenetic studies on bone marrow specimens from six patients with myelodysplastic syndrome, or acute myeloid leukemia, and a history of solid tumor managed solely by surgical resection. Structural or numerical deletions of chromosome 5 were identified in each of four patients with abnormal marrow karyotypes. Constitutional karyotypes were normal in two patients studied with clonal marrow chromosome abnormalities. Review of previously reported cases of myeloid neoplasia following resection of solid tumors disclosed a preponderance of chromosome 5 deletions. Predisposition to specific chromosome loss may influence genetic expression of disease in solid tumor patients developing hematologic malignancy.
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PMID:Predominance of chromosome 5 deletions in myeloid neoplasia associated with solid tumors managed by surgical excision. 155 Oct 74

Twenty-one patients with a median age of 9 years (0.5-19) underwent intensified myeloblative therapy: 1800 mg/m2 etoposide (VP) was added to 120 mg/kg cyclophosphamide (CY) and 12 Gy fractionated total body irradiation (FTBI) or 12-16 mg/kg busulfan (BU) for treatment of acute lymphoblastic leukemia (11 patients), acute myeloid leukemia (8 patients), non-Hodgkin's lymphoma (1 patient), or myelodysplastic syndrome (1 patient). Severe liver toxicity occurred in 5 of 7 children (71%) receiving short-term methotrexate (MTX) and additional cyclosporin A (CSA) for prophylaxis of graft-versus-host disease (GVHD). Three of them died of subsequent acute renal failure on days 8, 13, and 34. In contrast, acute severe organ toxicity occurred in only 1 of 14 children (7%) receiving the same intensified regimens who were autografted (7 pts) or received MTX alone for GVHD prophylaxis (7 pts). These observations suggest that GVHD prophylaxis with MTX and CSA may adversely influence the tolerance of intensified antileukemic regimens in children.
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PMID:Limited tolerance of intensified conditioning regimens in children receiving methotrexate/cyclosporin A for graft-versus-host disease prophylaxis. 155 71

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


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