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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The myelodysplastic syndromes (MDS) represent a group of syndromes having in common a defective production of one or more myeloid cell lines. They occur in patients which are more than 50 years old without any sex preponderance. The term MDS is replacing the obsolete and archaic term of 'preleukemia' and/or 'oligoblastic leukemia'. The more striking hematologic features are a discrepancy between a cellular bone marrow and a peripheral blood cytopenia. MDS may be idiopathic or secondary. Some of them precede or predispose to the subsequent development of an acute myeloid leukemia. A correct analysis of peripheral blood and bone marrow smears permits to classify MDS and to establish some prognostic features. Some syndromes are easily recognizable such as acquired idiopathic sideroblastic anemia, refractory anemia with excess of blasts, pure refractory cytopenia and acute myelodysplasia with myelofibrosis. Nevertheless this classification does not cover all these syndromes. Some of them with borderline features will be discussed separately. An analysis of a large series of MDS recently published in the literature will be presented as well as nosologic problems which arise. A conceptual effort should be made to recognize and evaluate the MDS.
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PMID:Myelodysplastic syndromes. 312 54

Bromodeoxyuridine (BrdUrd) is a pyrimidine analogue which is incorporated into the DNA of proliferating cells. When in vivo BrdUrd infusion is coupled with bivariate flow cytometry to measure cell BrdUrd incorporation and DNA content, both the percentage of DNA-synthesizing cells [BrdUrd-labeling index (LI)] and the DNA synthesis time (TS) can be determined on the same tissue sample. From experimentally determined LI and TS, the potential doubling time of the population and its cell production rate are calculated. To ascertain whether the BrdUrd infusion method is clinically feasible and if data are reliable, we studied patients with leukemia, refractory anemia, multiple myeloma, and brain and gastric tumors. The BrdUrd incorporation data were compared with those determined on duplicate samples with the techniques conventionally used for LI and TS values, i.e., 3H- and 14C-labeled thymidine autoradiography, respectively. The complete BrdUrd procedure takes 6-9 h, and no immediate toxicity from BrdUrd administration has been observed. In an 8-month period, 154 patients were studied. Successful LI and TS determinations were obtained in 78.9 and 59.7% of cases, respectively, more often in hematological than in solid tumors. The values for LI and TS assessed with the BrdUrd technique were very close to those found with 3H- and 14C-labeled thymidine autoradiography (r = 0.88, P less than 0.005, and r = 0.89; P less than 0.005, respectively). The potential doubling time and production rate were accordingly similar. These data indicate that in vivo BrdUrd infusion coupled with flow cytometry measurements can be performed in clinical settings and that this method is reliable. It could be used for kinetic studies in clinical trials aimed at evaluating the prognostic relevance of proliferative parameters and for planning radio- and/or chemotherapy.
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PMID:Cell kinetics in human malignancies studied with in vivo administration of bromodeoxyuridine and flow cytometry. 316 69

A combination of two intercalating agents, mitoxantrone and daunorubicin with vincristine (the DON regimen) was studied in 16 patients with refractory acute leukemia, including three patients with myeloblastic transformation of refractory anemia with excess of myeloblasts after the failure of first-line chemotherapy and one additional patient with AML relapsing while off therapy. All patients had been heavily pretreated prior to receiving the DON regimen, and all but two had previously received high-dose anthracyclines. Of the 17 patients, nine (53%) who achieved complete remissions (CR) had myeloblastic leukemia. The three patients with acute lymphocytic leukemia did not achieve CR. Cardiac toxicity occurred in two patients and contributed to death in one. These results in very poor risk leukemia suggest a possible synergism in the action of the two intercalating agents and absence of increased cardiotoxicity.
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PMID:A new combination of two intercalating agents (mitoxantrone + daunomycin) in adult refractory acute leukemia: the DON protocol. 316 47

A very rare case of myelodysplastic syndrome of long duration transformed into acute leukemia is reported. The syndrome presented with refractory anemia with ring sideroblasts and after eight years of favourable course abruptly turned into acute myelomonoblastic leukemia with a rapid fatal outcome caused by gram-negative sepsis. The disappearance of the ring-sideroblasts from the bone marrow is pointed out as a bad prognostic sign. Treatment of the myelodysplastic syndrome with small doses of cytosine arabinoside is discussed as well as the nonobligatory passing through the stage of a gradual increase of the blast cells before the transformation into acute leukemia.
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PMID:[Long-term myelodysplastic syndrome transformed into blastic leukemia]. 321 32

In April, 1985, a 60-year-old Japanese male was diagnosed as having refractory anemia with an excess of blasts (RAEB). He thus was treated solely with blood transfusions until June, 1986, when a new diagnosis revealed that his illness had been transformed into acute myelogenous leukemia (M2). Chromosome analysis at the initial diagnosis had revealed a normal male karyotype. When the subsequent diagnosis of AML was made, however, a chromosomal abnormality [46, XY, -20, +der (20) t (?8;20) (q22;p13)] was detected. Myelodysplastic syndrome (MDS) in patients evidencing a karyotypic alteration from the initial karyotypic findings progresses in severity that includes overt leukemia, and results in a shorter survival than in patients who show no further karyotypic changes. Therefore, the prognosis of patients with MDS can be predicted more accurately by subsequently reanalyzing their chromosomes after the initial analysis, as well as by examining their peripheral blood/counts, and by monitoring bone marrow cytology.
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PMID:[Refractory anemia showing excess of blasts (BAEB) that transformed into acute myelogenous leukemia (AML-M2) with a t (?8;20) chromosomal abnormality]. 323 Jun 41

A 64-year-old man was found to have a hemolytic anemia with a hematocrit of 0.28 (28%) during a routine evaluation. One month before this his hematocrit had been normal. Further studies revealed a myelodysplastic syndrome and acquired hemoglobin H disease. Eighteen months later this transformed into acute megakaryoblastic leukemia with disappearance of hemoglobin H, and shortly thereafter he had myelofibrosis develop. Acquired hemoglobin H disease, which is an alpha-thalassemia-like syndrome, results in the formation of an unstable hemoglobin composed of beta chain tetramers. This condition has been associated with preleukemia, sickle cell anemia, and hematologic malignancies. Although idiopathic myelofibrosis also has been described as a setting in which this thalassemic syndrome occurs, the present case is unusual in that the myelofibrosis was preceded by refractory anemia with leukemic transformation.
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PMID:Myelodysplastic syndrome with acquired hemoglobin H disease. Evolution through megakaryoblastic transformation into myelofibrosis. 327 51

Two cases of childhood myelodysplastic syndrome with chromosome abnormalities involving band 11p15 are described. The first case, with inv(11)(p15q23), had a complex clinical course; the initial diagnosis was aplastic anemia, then refractory anemia with excess of blasts in transformation (RAEB-t), and finally, before death, chronic myelomonocytic leukemia with hematologic features similar to those of chronic myelogenous leukemia (CML). The second case, with t(4;11)(p13;p15), progressed from RAEB to acute myelogenous leukemia (M2). In the literature, we found 12 patients with nonlymphocytic leukemia and chromosome abnormalities involving band 11p15, including seven cases with t(7;11)(p13-p15;p15); four cases (including the present case 1) showed CML-like hematologic features. It is suggested that translocations involving 11p15 are a nonrandom chromosome abnormality in nonlymphocytic leukemia.
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PMID:Childhood myelodysplastic syndromes with 11p15 translocation. 329 71

The analysis of 288 cases of polycythemia vera (PV) with a minimal follow-up of 10 years enabled us to study the characteristics of acute leukemia as observed in 33 patients (11.4%). In 50% of the patients (16 of 33), the malignant transformation is of the refractory anemia with excess of blasts (RAEB) type. Half of these further transform to acute nonlymphocytic leukemia (ANLL). Their life expectancy is not better than patients who abruptly develop ANLL. Leukemic transformation shows a frequency peak in the eighth year after initial evaluation in PV treated with chemotherapy and in the 11th year in patients treated with radiotherapy. In 30% of the patients myelofibrosis, or the spent phase of PV, is present before the transformation to acute leukemia (AL). This complication is, however, part of the natural history of PV and is observed in 20% of PV patients at 10 years when leukemic transformation is absent. Marrow fibrosis can therefore not be considered as a preleukemic phase. It was also noted that the occurrence of myeloid metaplasia/myelofibrosis is more frequent and begins earlier in patients treated by phlebotomy alone, and who do not transform to leukemia. The clinical characteristics of these AL, including high frequency of partial marrow invasion, difficulties in cytologic classification, a peak incidence similar to that in patients treated by chemotherapy or radiotherapy for a prior malignancy, multiple chromosome abnormalities, and poor response to therapy are all highly suggestive of secondary leukemias.
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PMID:Acute leukemia and myelodysplasia in polycythemia vera. A clinical study with long-term follow-up. 333 54

This paper analyzes the hematologic features and outcome of 13 patients with chromosome 5 abnormalities (monosomy 5 or deletion of 5q), either isolated or with additional anomalies. Among four patients with isolated del (5q), two had a stable refractory macrocytic anemia with thrombocytosis (5q-syndrome). All nine patients with complex karyotypes had acute leukemia or refractory anemia with excess of blasts in acute transformation; two cases were TdT-positive, with a lymphoid or a mixed phenotype. In seven patients, preleukemia preceded overt leukemia, and in six, a prior therapeutic, or occupational exposure to mutagens/carcinogens had occurred. Additional chromosome 7 abnormalities were seen in four cases. The median survival of patients with complex karyotypes was 19 months from the time of diagnosis of the hematologic disorder and 5 months from the time of identification of the chromosome 5 abnormality. Pathogenetic implications of the chromosome 5 monosomy or del (5q) through a proto-oncogene activation and the putative hemopoietic stem cell involvement in a clonal disease are discussed.
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PMID:Hematologic and clinical features of patients with chromosome 5 monosomy or deletion (5q). 335 40

Novel techniques were used to detect which cell lineages were affected by monosomy 7 in a patient who had myelodysplastic syndrome and later developed acute leukemia. The patient had had paroxysmal nocturnal hemoglobinuria for 20 years before developing refractory anemia with excess of blasts. Cytogenetic analysis at the myelodysplastic stage disclosed monosomy 7 in bone marrow mitoses. Restriction fragment length polymorphism analysis of fractionated white blood cells with the chromosome 7-specific probes MetH and MetD revealed that blood monocytes and most bone marrow erythroblasts but not blood granulocytes or lymphocytes were affected by monosomy 7. The patient later developed acute myelomonocytic leukemia with blast cells positive for markers of the myelomonocytic lineage but negative for granulocytic markers in a standard surface marker analysis. The leukemic blast cells had monosomy 7 as determined by direct cytogenetic investigation. Thus, the monocytes were found to be affected by monosomy 7 in this patient 8 months before her myelodysplastic syndrome progressed to acute myelomonocytic leukemia, and the affected cells had the same biologic markers at both stages of the disease.
Leukemia 1988 Feb
PMID:Monocytic involvement by monosomy 7 preceded acute myelomonocytic leukemia in a patient with myelodysplastic syndrome. 342


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