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

Refractory anemia (RA) is an hematologic disorder at risk of developing into a malignancy (hemopoietic dysplasia). Information on hemopoietic dysplasias is useful for sharpening the appropriate diagnostic criteria and for the search of an appropriate therapy. Moreover, hemopoietic dysplasias provide an interesting opportunity, in humans, for studying a developing leukemia, or a disease situated at the boundary of leukemia. This paper reports on the evolution of RA in 13 patients followed up more than 2 years, through clinical observation, blood and marrow examination, and karyotype analysis. 4 of these 13 patients developed acute or subacute myeloid leukemia. An additional patient died because of severe thrombocytopenia. In these 5 patients, dyserythropoiesis was accompanied by thrombocytopenia, marrow myeloblastosis, and nonrandom chromosome abnormalities.
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PMID:Clinical contribution to the knowledge of hemopoietic dysplasias: long-term follow-up of 13 patients with refractory anemia. 9 96

Studies of in vitro platelet aggregation were done in five patients with refractory anemia and two with acute myelomonocytic leukemia. The macroscopic results as well as the general ultrastructural findings were reviewed in a companion paper. Electron microscopic analysis of changes in the individual platelets within aggregates revealed a striking heterogeneity, both in the degree of response of each platelet are in the ultrastructural characteristics of the platelet population. Many of the unaggregated platelets had reacted individually, resembling the platelets of patients with Glanzmann's thrombasthenia. There were other abnormalities suggesting the presence of surface defects, such as the presence of areas of obliteration of the interplatelet space (so-called tight connections). One of the most striking findings was a peculiar dissociation between the different components of the aggregation sequence.
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PMID:Ultrastructure of platelet aggregation in refractory anemia and myelomonocytic leukemia. II. Individual platelet abnormalities: thrombasthenia-like platelets, surface defects, and dissociation phenomena. 18 Mar 59

The clinical homogeneity of myeloproliferative syndromes associated with a 5 q- marker can be contested, but nevertheless finds support in the 2 case reports we have cited. One of these observations of refractory anemia with partial myeloblastosis and 5 q- marker has shown a transformation into an acute myelomonocytic leukemia with clonal chromosomal evolution.
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PMID:Cytogenetic evidence of clonal evolution in 5q- anemia. 26 80

The results of a prospective study of 58 patients with refractory anemia and partial blastic infiltration of the bone marrow lead to the following conclusions. The median survival (12 months from diagnosis) is shorter and the rate of acute leukemia as cause of death (60%) higher than in other retrospective series. This group of patients, however, appears to be a "continuum" of preleukemic states with more or less rapid evolution, so that the exclusion of the most severe cases appears unjustified. Based on the degree of bone marrow blastosis, and also on the degree of blood cytopenias, the anomalies of 59 Fe incorporation kinetics and the bone marrow stem-cell cultures, it is possible to derive a plausible prognosis for individual patients, which could aid the choice of therapy. Androgen therapy does not accelerate leukemic evolution, but does not improve the bone marrow insufficiency. Cytosine-arabinoside at low dosage exhibited no toxicity, but did not delay the appearance of overt leukemia.
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PMID:Refractory anemia with excess of blast cells: prognostic factors and effect of treatment with androgens or cytosine arabinoside. Results of a prospective trial in 58 patients. Cooperative Group for the Study of Aplastic and Refractory Anemias. 38 2

The clinical, hematologic and histologic characteristics of six patients with refractory anemia with deletion of the long arm of chromosome No. 5 are described. These patients had a distinct hematologic picture with macrocytic anemia of mild to moderate severity, normal to low leukocyte count and increased platelet count. The long arm of chromosome No. 5 was deleted in the majority of bone marrow metaphases. The main cause of anemia was underproduction with decreased erythroid precursors in the bone marrow and no increase in peripheral blood reticulocytes. Two of five patients responded transiently to the administration of androgens. In vitro evaluation of the bone marrow growth pattern in semisolid agar culture system was performed in three patients and was found to be normal and distinct from that in patients with preleukemia. In a follow up of up to five years, no patient had changed hematologically and in none had leukemia developed. The 5q-syndrome is a distinct hematologic entity and probably more common than hitherto realized. This diagnosis may have therapeutic and prognostic implications.
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PMID:Macrocytic anemia, thrombocytosis and nonlobulated megakaryocytes: the 5q-syndrome, a distinct entity. 45 27

The prognostic value of marrow chromosome studies was examined in 112 "preleukemic" patients followed for at least one year or until death. Based on recent definitions, 49 patients were classified as myeloproliferative disorders (MPD) (polycythemia vera, myelofibrosis, undifferentiated myeloproliferative disorder, essential thrombocythemia), and 58 as cytopenic states (refractory anemia, pancytopenia). In each group, approximately one-third had a chromosomally-abnormal clone. For MPD, this had little predictive value, but in the cytopenias, 77% with a cytogenetic abnormality developed leukemia versus 39% without. Twelve cytopenic patients had multiple alterations involving more than 2 chromosomes and 11 died within 6 months, 9 with leukemia. Such patients may warrant consideration for aggressive chemotherapy before the appearance of clinical leukemia. Banding studies did not reveal any specific chromosome abnormalities consistently associated with these various preleukemic disorders, or with progression to leukemia, but nonrandom alterations were noted involving chromosomes 1, 5, 7-9, and 20 in the MPD group, and chromosomes 6 and 16 in the cytopenic patients. Correlation of these data with other reports indicates that certain cytogenetic abnormalities involving specific segments of the human genome confer a selective growth advantage on hemic clones which may present clinically as either preleukemia or leukemia.
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PMID:Chromosome studies in preleukemic states. IV. Myeloproliferative versus cytopenic disorders. 71 5

A 49-year-old white woman with refractory anemia subsequently developed acute myelomonocytic leukemia with paraproteinemia 12 months later. The paraprotein was characterized as immunoglobulin G, type kappa, and the Bence Jones protein as free kappa chains. Further studies, including electron microscopy, cytochemistry, and immunofluorescence provided evidence for synthesis of the paraprotein, both in vivo and vitro, by the myelomonocytic leukemic cells.
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PMID:Acute myelomonocytic leukemia associated with paraproteinemia. 81 50

A study was done with 27 patients who met the following criteria: (1) anemia, (2) cellular bone marrow not diagnostic of leukemia, (3) absence of underlying disease that could account for the hematologic abnormalities at time of initial study and (4) absence of iron, B(12) or folate deficiency. Of the 27 patients, 13 had ringed sideroblasts and 14 did not. Eleven patients received corticosteroids, 18 received folate, 23 pyridoxine and 12 androgens. Two partial responses occurred in the sideroblastic group and were attributed to androgen therapy in one patient and pyridoxine therapy in the other. In the nonsideroblastic group, two partial responses occurred which were attributed to prednisone therapy. Transfusions were required in 23 patients. Leukemia developed in six patients. It is concluded that currently used treatments have little effect on refractory anemia and that in most patients continuing transfusions are required. In a small percentage of patients, there is transformation to leukemia.
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PMID:Refractory sideroblastic and nonsideroblastic anemia: a review of 27 cases. 89 52

In vitro aggregation of the platelets from four patients with refractory anemia and two patients with acute myelomonocyctic leukemia revealed distinctive abnormalities. In five patients, there was deficient or minimal aggregation with adenosine diphosphate (ADP), epinephrine, or collagen and only one wave of aggregation could be elicited with ADP at any concentration. Ultrastructural studies revealed numerous isolated platelets, small aggregates with few platelet pseudopods, and the presence of a characteristic type of aggregate with heterogeneous platelet composition combining features of both the primary and the secondary waves of aggregation. These "mixed aggregates" were particularly abundant in the four patients who had refractory anemia and may constitute the structural basis of the single wave of aggregation observed.
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PMID:Ultrastructure of platelet aggregation in refractory anemia and myelomonocytic leukemia. I. Ultrastructure of aggregation in normal controls and general defects in refractory anemia and myelomonocytic leukemia. 106 6

Seventy-nine patients with a refractory anemia and partial myeloblastic medullary infiltration have been studied, according to a prospective common protocol. All the patients have been treated with androgens, at high dosage and for at least 10 months if surviving. This study enables to precise the natural history of the disease and to define some criteria valuable for the prognosis. It demonstrates that the classification of this clinical entity as a smoldering or pre-leukemia is justified: 63% of the patients died from acute myeloblastic leukemia. The disease is very severe: the median of survival from the diagnosis is only 13 months. Androgen therapy appears to have little if any effect on the anemia, granulocytopenia and thrombocytopenia; it does not seem to increase the patients' life expectancy.
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PMID:[Refractory anemias with partial myeloblastosis. Analysis of a protocol comprising 79 cases. 1. Clinical characteristics and evolution under androgen therapy]. 106 63


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