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

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

The major complications of the myelodysplastic syndromes (MDS) are related to cytopenia and evolution to acute myeloid leukemia (AML). Hematopoietic growth factors are only of limited benefit to alleviate the cytopenia. Therapy in MDS patients over the age of 50 should aim at prolonging survival while limiting the risk of toxicity. Those with stable disease should only receive supportive care; those with progressive cytopenia should have a trial with low-dose chemotherapy. Aggressive chemotherapy should only be reserved for those failing low-dose therapy. Therapy in MDS patients under the age of 50 should aim at cure of the disease. Although aggressive chemotherapy can induce complete remission in the majority of these patients, remission is usually short. Allogeneic bone marrow transplantation is probably the only curative option in these patients and should be the treatment of choice.
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PMID:Complications and treatment of the myelodysplastic syndromes. 173 64

Allogeneic bone marrow transplantation is an effective treatment for myelodysplastic syndromes, providing a probable cure in about one-third of cases overall. It is generally reserved for patients under 50 years who have an HLA-compatible donor. Post-transplant disease-free survival rates vary according to several prognostic factors, which often overlap with those predicting the spontaneous outcome of the disease. Consequently, it is sometimes difficult to choose the indications and timing of bone marrow transplantation in this setting. Here we review the literature in an attempt to draw up relevant guidelines.
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PMID:Indications and timing of allogeneic bone marrow transplantation in myelodysplastic syndromes. 947 29

In the elderly, acute myeloid leukemia (AML) is characterized by a poorer prognosis than in younger patients, due to either host related factors (poor performance status, co-morbid diseases, organ function impairment) or the biology of leukemia itself (high incidence of adverse cytogenetic abnormalities, high frequency of preceding myelodysplastic syndromes, intrinsic resistance to cytotoxic drugs). Current therapeutic results are mostly unsatisfactory and studies reporting high rates of complete remission are probably influenced by selection biases as suggested by the low rate of elderly patients inclusion into cooperative trials. Availability of intensive support including hematopoietic growth factors could stimulate clinicians to manage an increasing number of elderly patients with AML with aggressive programs. However, chemotherapy in the elderly is difficult, costly and usually associated with high morbidity and mortality rate. Therefore, all efforts should be made to identify those subset of elderly patients in whom aggressive treatment may result in a true improvement of disease free and overall survival. The critical analysis of our five years experience, as reported here, seems to suggest that older AML patients displaying unfavourable prognostic factors at diagnosis (i.e., adverse karyotype and high serum LDH levels), but clinically eligible for intensive chemotherapy, do not actually benefit from an aggressive approach. A blind attempt to treat these patients aggressively may be associated with a life threatening toxicity not counterbalanced by an actual survival advantage. We suggest therefore that aggressive treatment should be reserved for elderly AML cases in whom the presence of good prognostic factors at diagnosis predicts that the loss of some patients due to toxicity may be balanced by the achievement of a substantial proportion of long term survivors. Finally, given the biological and clinical heterogeneity of elderly AML patients, a more precise prognostic categorization of these patients would be particularly useful in interpreting future therapeutic results.
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PMID:Acute myeloid leukemia in the elderly: a critical review of therapeutic approaches and appraisal of results of therapy. 968 34

Myelodysplastic syndromes (MDS) are a heterogeneous group of disorders with a variable clinical course and prognosis. Treatment should be individualized based on the patient's age, subtype, percent blasts in the marrow, and cytogenetics. The use of the International Prognostic Scoring Index is helpful in assigning prognosis. The standard of care for low-risk patients is supportive care. Low-risk patients with symptomatic anemia should be considered for a trial of erythropoietin. The serum erythropoietin (EPO) level may help predict response to treatment. The treatment of the symptomatic and high-risk patient is unclear. Low-dose cytarabine, amifostine, and 5-azacitidine can induce responses in selected patients, but the duration of responses is short, and treatment does not appear to prolong survival. Intensive chemotherapy should be reserved for high-risk, younger patients. Topotecan and intermediate cytarabine appear to have an active regimen, but remissions are short. Younger patients who present with high-risk MDS without an antecedent history of MDS should receive intensive acute myeloid leukemia (AML) induction chemotherapy. Younger patients with high-risk MDS and an HLA-compatible donor should be offered an allogeneic stem cell transplant.
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PMID:Myelodysplastic syndromes. 1205 62

The International Prognostic Scoring System (or, more conveniently, the marrow blast percentage) can be used to divide patients with myelodysplasia into those with better (International Prognostic Scoring System low/ intermediate-1, or <10% blasts) and worse (International Prognostic Scoring System intermediate-2/high, or >10% blasts) prognoses. There is no treatment known to produce responses in the great majority of patients in either group. Hence, most patients should be considered for clinical trials. Exceptions are cases with low serum erythropoietin levels or low marrow cellularity; such cases may benefit from erythropoietin with or without granulocyte colony-stimulating factor or antithymocyte globulin, respectively. A wide variety of new agents are in clinical trial. These can be grouped into biologic or targeted, therapies, acute myelogenous leukemia-type chemotherapy, and allogeneic stem cell transplants. In general, competing risk-to-benefit ratios and consideration of natural histories suggest that patients with a better prognosis should receive biologic therapies first, with transplant reserved until failure. In higher-risk patients, particularly those who are relatively young or have a normal karyotype, acute myelogenous leukemia-type chemotherapy or transplant should be considered earlier in the course. The advent of nonmyeloablative (mini) transplant protocols has extended to 70 to 75 years the age at which transplantation can be performed, although the efficacy of such protocols is unknown. Current data do not permit recommendation of specific regimens in patients with a better or worse prognosis; rather, emphasis should be placed on entry into a clinical trial Finally, because other causes of cytopenias are more treatable, the diagnosis of myelodysplastic syndrome should depend on more than the presence of dysplasia, unless the dysplasia is very severe.
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PMID:Current challenges in therapy of myelodysplastic syndromes. 1248 13

In the past seven years numerous genes that influence iron homeostasis have been discovered. Dr. Beutler provides a brief overview of these genes, genes that encode HFE, DMT-1, ferroportin, transferrin receptor 2, hephaestin, and hepcidin to lay the groundwork for a discussion of the various clinical forms of iron storage disease and how they differ from one another. In Section I, Dr. Beutler also discusses the types of hemochromatosis that exist as acquired and as hereditary forms. Acquired hemochromatosis occurs in patients with marrow failure, particularly when there is active ineffective erythropoiesis. Hereditary hemochromatosis is most commonly due to mutations in the HLA-linked HFE gene, and hemochromatosis clinically indistinguishable from HFE hemochromatosis is the consequence of mutations in three transferrin receptor-2 gene. A more severe, juvenile form of iron storage disease results from mutations of the gene encoding hepcidin or of a not-yet-identified gene on chromosome 1q. Autosomal dominant iron storage disease is a consequence of ferroportin mutations, and a polymorphism in the ferroportin gene appears to be involved in the African iron overload syndrome. Evidence regarding the biochemical and clinical penetrance of hemochromatosis due to mutations of the HFE gene is rapidly accumulating. These studies, emanating from several centers in Europe and the United States, all agree that the penetrance of hemochromatosis is much lower than had previously been thought. Probably only 1% of homozygotes develop clinical findings. The implications of these new findings for the management of hemochromatosis will be discussed. In Section II, Dr. Victor Hoffbrand discusses the management of iron storage disease by chelation therapy, treatment that is usually reserved for patients with secondary hemochromatosis such as occurs in the thalassemias and in patients with transfusion requirements due to myelodysplasia and other marrow failure states. Tissue iron can be estimated by determining serum ferritin levels, measuring liver iron, and by measuring cardiac iron using the MRI-T2* technique. The standard form of chelation therapy is the slow intravenous or subcutaneous infusion of desferoxamine. An orally active bidentate iron chelator, deferiprone, is now licensed in 25 countries for treatment of patients with thalassemia major. Possibly because of the ability of this compound to cross membranes, it appears to have superior cardioprotective properties. Agranulocytosis is the most serious complication of deferiprone therapy and occurs in about 1% of treated patients. Deferiprone and desferoxamine can be given together or on alternating schedules. A new orally active chelating agent ICL 670 seems promising in early clinical studies. In Section III, Dr. James Cook discusses the most common disorder of iron homeostasis, iron deficiency. He will compare some of the standard methods for identifying iron deficiency, the hemoglobin level, transferrin saturation, and mean corpuscular hemoglobin and compare these with some of the newer methods that have been introduced, specifically the percentage of hypochromic erythrocytes and reticulocyte hemoglobin content. The measurement of storage iron is achieved by measuring serum ferritin levels. The soluble transferrin receptor is a truncated form of the cellular transferrin receptor and the possible value of this measurement in the diagnosis of iron deficiency will be discussed. Until recently iron dextran was the only parental iron preparation available in the US. Sodium ferric gluconate, which has been used extensively in Europe for many years, is now available in the United States. It seems to have a distinct advantage over iron dextran in that anaphylactic reactions are much less common with the latter preparation.
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PMID:Iron deficiency and overload. 1463 76

The treatment algorithm for the patient with myelodysplastic syndrome (MDS) is in the process of being revitalized based on recent results of clinical trials. Historically, the goal for lower-risk patients was hematologic improvement, and disease modification was reserved for patients in the higher-risk category. Recent data now favor shifting emphasis away from supportive care alone and toward altering the disease course and prolonging survival, particularly in patients with intermediate-2 and high-risk disease. In addition, there is a greater appreciation for the significant morbidity and mortality resulting from MDS and increased efforts to improve quality of life while pursuing treatment. Immunomodulation with lenalidomide has yielded durable cytogenetic and hematologic responses and also has shown potential to alter disease course. Similarly, immunosuppression with antithymocyte globulin has shown sustained hematologic responses in selected patient subgroups. The methyltransferase inhibitors have demonstrated the ability to alter the natural history of disease and thus prolong time to leukemic transformation. In addition, azacitidine has shown the capacity to extend survival compared with the previous gold standard of conventional care regimens. With these new data, evaluation of treatment options should no longer focus on response rates as the sole endpoint but rather on time to leukemic transformation and survival. Timing of available therapies, including stem cell transplantation, should be incorporated into the new treatment paradigm, with end goals of prolonging survival and optimizing patient outcomes.
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PMID:Changing the treatment paradigm in myelodysplastic syndromes. 1881 6

Over the last decade, treatment approaches for patients with myelodysplastic syndromes (MDS) have improved significantly. Treatment of MDS is tailored to the specific risk characteristics of the patient. In general, patients are divided into lower- and higher-risk categories. Without therapy, prognosis of patients with higher-risk MDS is poor, and treatments should be directed to improve survival. Prognosis of patients with lower-risk MDS is more heterogeneous, and therapies are usually directed to minimize transfusion needs and potentially to alter the natural course of the disease. Treatment options for patients with higher-risk MDS include hypomethylating agents (azacitidine and decitabine), intensive chemotherapy (ICT), and allogeneic stem-cell transplantation (alloSCT). The use of the hypomethylating agents has transformed the approach to this patient population, in particular older individuals, for whom ICT and alloSCT are not an option. In lower-risk MDS, treatment strategies are used sequentially and usually include observation in patients with low risk and no transfusion dependency, growth factors, and lenalidomide for patients with alteration of chromosome 5 and anemia. The use of hypomethylating agents is less understood in this group of patients. AlloSCT is usually reserved for patients with lower-risk MDS closer to the time of transformation. In this short review, we discuss treatment alternatives for patients with MDS and delineate some of the ongoing challenges, including the development of better front-line strategies for patients with higher-risk disease, the concept of altering the natural course of the disease in lower-risk MDS, and the development of new treatment approaches for patients who do not benefit from hypomethylating agents.
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PMID:Hypomethylating agents and other novel strategies in myelodysplastic syndromes. 2122 May 89

Reduced-intensity conditioning (RIC) umbilical cord blood (UCB) transplantation is increasingly used in hematopoietic stem cell transplantation (HCT) for older and medically unfit patients. Data on the efficacy of HCT after RIC relative to myeloablative conditioning (MAC) are limited. We compared the outcomes of acute myeloid leukemia (AML) patients >18 yrs who received UCB grafts after either RIC or MAC. One hundred nineteen adult patients with AML in complete remission (CR) underwent an UCB transplant after RIC (n =74, 62%) or MAC (n = 45, 38%) between January 2001 and December 2009. Conditioning was either reduced intensity and consisted of cyclophosphamide 50 mg/kg, fludarabine 200 mg/m(2), and total-body irradiation (TBI) 200 cGy or myelablative and consisted for cyclophosphamide 120 mg/kg, fludarabine 75 mg/m(2), and TBI 1200-1320 cGy. All patients received cyclosporine (day -3 to day +180) and mycophenolate mofetil (day -3 to day +45) post-HCT immunosuppression and hematopoietic growth factor. Use of RIC was reserved for patients >45 years (n = 66, 89%) or preexisting severe comorbidities (n = 8, 11%). The 2 groups were similar except for preceding myelodysplastic syndrome (RIC = 28% versus MAC = 4%, P < .01) and age that was dictated by the treatment protocols (median, RIC = 55 years versus MAC = 33years; P < .01). The incidence of neutrophil recovery at day +42 was higher with RIC (94% versus MAC = 82%, P < .1), whereas platelet recovery at the sixth month was similar (RIC = 68% versus MAC = 67%, P = .30). Incidence of grade II-IV acute graft-versus-host disease (aGVHD) (RIC = 47% versus MAC = 67%, P < .01) was decreased with similar incidence of chronic GVHD (cGVHD) (RIC = 30% versus MAC = 34%, P = .43). Median follow-up for survivors was 3.8 and 4.5 years for RIC and MAC, respectively (P = .4). Using RIC, 3-year leukemia-free survival (LFS) was decreased (31% versus MAC = 55%, P = .02) and 3-year relapse incidence was increased (43% versus MAC = 9%, P < .01). Two-year transplant-related mortality (TRM) was similar (RIC = 19% versus MAC = 27%; P = .55). In multivariate analysis, RIC recipients and those in CR2 with CR1 duration <1 year had higher risk of relapse and poorer LFS with no independent predictors of TRM. UCB with RIC extends the use of allogeneic HCT for older and frail patients without excessive TRM with greater benefit for patients in CR1 and CR2 with longer CR1.
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PMID:Effect of conditioning regimen intensity on acute myeloid leukemia outcomes after umbilical cord blood transplantation. 2123 21


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