Term
| Myelodysplastic syndromes (MDS) |
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Definition
| Clonal stem cell disorder |
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Term
| General Characteristics of Myelodysplastic syndromes (MDS) |
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Definition
| Ineffective hematopoiesis, increased apoptosis and evidence of dyshematopoiesis |
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Term
| Four subgroups of MDS recognized by the WHO classification system |
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Definition
| Refractory anemia (RA), Refractory anemia with ring sideroblasts (RARS), Refractory anemia with multi-lineage dysplasia (RCMD), and refractory anemia with excess blasts type 1 (RAEB-1) |
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Term
| Key morphological criteria to distinguish Refractory Anemia (RA) |
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Definition
| anemia with <1% blasts in peripheral blood, uni-lineage erythroid dysplasia in bone marrow with <5% blasts |
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Term
| Key clinical criteria to distinguish Refractory Anemia (RA) |
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Definition
| anemia that is non-responding to all conventional forms of therapy, affects 10-20% of MDS patients |
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Term
| Key morphological criteria to distinguish Refractory Anemia with ring sideroblasts (RARS) |
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Definition
| anemia with no blasts present in peripheral blood, uni-lineage erythroid dysplasia with 15% containing ring sideroblasts and <5% blasts in bone marrow |
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Term
| Key clinical criteria to distinguish Refractory Anemia with ring sideroblasts (RARS) |
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Definition
| affects 3-10% of MDS patients |
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Term
| Key morphological criteria to distinguish Refractory Anemia with multi-lineage dysplasia (RCMD) |
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Definition
| cytopenias with <1% blasts in the peripheral blood, multi-lineage dysplasia with possible ring sideroblasts and <5% blasts in bone marrow |
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Term
| Key clinical criteria to distinguish Refractory Anemia with multi-lineage dysplasia (RCMD) |
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Definition
| affects 30% of MDS patients |
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Term
| Key morphological criteria to distinguish Refractory Anemia with excess blasts type 1 (RAEB-1) |
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Definition
| cytopenias with 2-9% blasts in peripheral blood, uni-lineage or multi-lineage dysplasia with 5-9% blasts in the bone marrow |
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Term
| Key clinical criteria to distinguish Refractory Anemia with excess blasts type 1 (RAEB-1) |
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Definition
| affects 40% of MDS patients, most common subtype |
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Term
| Laboratory findings characteristic of MDS |
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Definition
| dysgranulopoiesis and dysmegakaryopoiesis in bone marrow, changes in iron studies, cobalamin and folic acid levels can be increased, decrease in total T lymphocytes, peripheral blood shows cytopenias, dysplasia, macrocytic, dimorphic RBCs, abnormal WBCs, and both quantitative and qualitative platelet abnormalities |
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Term
| Changes in morphology characteristic of MDS |
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Definition
| RBCs are macrocytic, dimorphic, with anisocytosis, poikilocytosis, which contain inclusions. WBCs are shifted to the left with hypo or agranular forms, hyposegmentation and hypersegmentation with donut or ring-shaped nuclei. Platelets are giant and hypogranular with circulating micromegakaryocytes. Bone marrow shows N:C asynchrony, giant, multi-nucleated erythroid precursors, karyorrhexis and ringed sideroblasts, abnormal granulocyte precursors with large primary granules, secondary granules and irregular cytoplasmic basophilia, megakaryocytes are abnormal because they lack granules |
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Term
| Definition of WHO category Myelodysplastic/myeloproliferative diseases |
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Definition
| clinical, laboratory, and morphologic features that support a diagnosis of both MPD and MDS but do not meet the criteria of the other entities included in the MDS/MPD category. |
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Term
| General characteristics of WHO category of Myelodysplastic/myeloproliferative diseases |
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Definition
| <20% blasts in blood and bone marrow and prominent myeloproliferative features associated with thrombocytosis or leukocytosis. Proliferation of one more of the myeloid lineages that are ineffective and/or dysplastic |
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Term
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Definition
| genetic mutation which produces an abnormal hematopoietic stem cell causes dyshematopoiesis, normal clones coexist in marrow with abnormal clones, the course of disease is variable, and MDS can evolve into AML |
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Term
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Definition
| supportive treatment via transfusions, prophylactic/curative antibiotics or hematopoietic cytokines, chemotherapy, or bone marrow transplant which is the only curative treatment and works best in young patients. |
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Term
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Definition
| Median survival rate is <2 years, mortality rate is 58-72%, most patients transform to an AML (10-40%), IPSS scale to assist in prognosis and selection of therapy |
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Term
| Relationship between MDS and Acute Leukemia |
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Definition
| when the chromosomal genetic abnormalities increase the percent of blasts increase which causes a block in maturation and decreased apoptosis this signifies a transformation to AML which occurs in 10-40% of patients |
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Term
| Results of cytogenetic tests that indicate MDS |
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Definition
| Abnormal karyotypes causes by unbalanced mutations which most commonly involve chromosomes 5, 7 and 8 |
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Term
| Results of molecular tests the indicate MDS |
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Definition
| abnormal proteins from unbalanced mutations have more frequent and complex abnormalities |
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Term
| How does MDS different from myeloproliferative disorders, acute leukemia, and other hematopoietic disorders in peripheral blood |
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Definition
| prominent left shift with eosinophils, hypersegmented neutrophils, increased blasts (<5%), cytopenias in at least 2 cell lines, abnormalities in all cell lines |
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Term
| How does MDS different from myeloproliferative disorders, acute leukemia, and other hematopoietic disorders in bone marrow |
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Definition
| blasts increased <20% and dyshematopoiesis with hypercellularity |
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Term
| blasts increased <20% and dyshematopoiesis with hypercellularity |
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Definition
| Unbalanced chromosomal mutations which involve chromosome 5,7 and |
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Term
| Laboratory tests which are helpful in diagnosing and differentiating MDS |
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Definition
| peripheral blood smear, CBC, and bone marrow aspirate, possible karyotype |
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